Contract Address Details

// SPDX-License-Identifier: MIT
pragma solidity =0.7.6;
pragma abicoder v2;

/// @notice A fork of Multicall2 specifically tailored for the ElkDex Interface
contract ElkDexInterfaceMulticall {
    struct Call {
        address target;
        uint256 gasLimit;
        bytes callData;
    }

    struct Result {
        bool success;
        uint256 gasUsed;
        bytes returnData;
    }

    function getCurrentBlockTimestamp() public view returns (uint256 timestamp) {
        timestamp = block.timestamp;
    }

    function getEthBalance(address addr) public view returns (uint256 balance) {
        balance = addr.balance;
    }

    function multicall(Call[] memory calls) public returns (uint256 blockNumber, Result[] memory returnData) {
        blockNumber = block.number;
        returnData = new Result[](calls.length);
        for (uint256 i = 0; i < calls.length; i++) {
            (address target, uint256 gasLimit, bytes memory callData) =
                (calls[i].target, calls[i].gasLimit, calls[i].callData);
            uint256 gasLeftBefore = gasleft();
            (bool success, bytes memory ret) = target.call{gas: gasLimit}(callData);
            uint256 gasUsed = gasLeftBefore - gasleft();
            returnData[i] = Result(success, gasUsed, ret);
        }
    }
}
        

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Immutable state
/// @notice Functions that return immutable state of the router
interface IPeripheryImmutableState {
    /// @return Returns the address of the ElkDex V3 factory
    function factory() external view returns (address);

    /// @return Returns the address of WETH9
    function WETH9() external view returns (address);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.6.0;

import '@openzeppelin/contracts/token/ERC20/IERC20.sol';

library TransferHelper {
    /// @notice Transfers tokens from the targeted address to the given destination
    /// @notice Errors with 'STF' if transfer fails
    /// @param token The contract address of the token to be transferred
    /// @param from The originating address from which the tokens will be transferred
    /// @param to The destination address of the transfer
    /// @param value The amount to be transferred
    function safeTransferFrom(
        address token,
        address from,
        address to,
        uint256 value
    ) internal {
        (bool success, bytes memory data) =
            token.call(abi.encodeWithSelector(IERC20.transferFrom.selector, from, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'STF');
    }

    /// @notice Transfers tokens from msg.sender to a recipient
    /// @dev Errors with ST if transfer fails
    /// @param token The contract address of the token which will be transferred
    /// @param to The recipient of the transfer
    /// @param value The value of the transfer
    function safeTransfer(
        address token,
        address to,
        uint256 value
    ) internal {
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(IERC20.transfer.selector, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'ST');
    }

    /// @notice Approves the stipulated contract to spend the given allowance in the given token
    /// @dev Errors with 'SA' if transfer fails
    /// @param token The contract address of the token to be approved
    /// @param to The target of the approval
    /// @param value The amount of the given token the target will be allowed to spend
    function safeApprove(
        address token,
        address to,
        uint256 value
    ) internal {
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(IERC20.approve.selector, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'SA');
    }

    /// @notice Transfers ETH to the recipient address
    /// @dev Fails with `STE`
    /// @param to The destination of the transfer
    /// @param value The value to be transferred
    function safeTransferETH(address to, uint256 value) internal {
        (bool success, ) = to.call{value: value}(new bytes(0));
        require(success, 'STE');
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;

import '@openzeppelin/contracts/token/ERC721/IERC721.sol';

/// @title ERC721 with permit
/// @notice Extension to ERC721 that includes a permit function for signature based approvals
interface IERC721Permit is IERC721 {
    /// @notice The permit typehash used in the permit signature
    /// @return The typehash for the permit
    function PERMIT_TYPEHASH() external pure returns (bytes32);

    /// @notice The domain separator used in the permit signature
    /// @return The domain seperator used in encoding of permit signature
    function DOMAIN_SEPARATOR() external view returns (bytes32);

    /// @notice Approve of a specific token ID for spending by spender via signature
    /// @param spender The account that is being approved
    /// @param tokenId The ID of the token that is being approved for spending
    /// @param deadline The deadline timestamp by which the call must be mined for the approve to work
    /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
    /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
    /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
    function permit(
        address spender,
        uint256 tokenId,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external payable;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;

import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@elkdex/v3-core/contracts/libraries/LowGasSafeMath.sol';

import './PeripheryPayments.sol';
import '../interfaces/IPeripheryPaymentsWithFee.sol';

import '../interfaces/external/IWETH9.sol';
import '../libraries/TransferHelper.sol';

abstract contract PeripheryPaymentsWithFee is PeripheryPayments, IPeripheryPaymentsWithFee {
    using LowGasSafeMath for uint256;

    /// @inheritdoc IPeripheryPaymentsWithFee
    function unwrapWETH9WithFee(
        uint256 amountMinimum,
        address recipient,
        uint256 feeBips,
        address feeRecipient
    ) public payable override {
        require(feeBips > 0 && feeBips <= 100);

        uint256 balanceWETH9 = IWETH9(WETH9).balanceOf(address(this));
        require(balanceWETH9 >= amountMinimum, 'Insufficient WETH9');

        if (balanceWETH9 > 0) {
            IWETH9(WETH9).withdraw(balanceWETH9);
            uint256 feeAmount = balanceWETH9.mul(feeBips) / 10_000;
            if (feeAmount > 0) TransferHelper.safeTransferETH(feeRecipient, feeAmount);
            TransferHelper.safeTransferETH(recipient, balanceWETH9 - feeAmount);
        }
    }

    /// @inheritdoc IPeripheryPaymentsWithFee
    function sweepTokenWithFee(
        address token,
        uint256 amountMinimum,
        address recipient,
        uint256 feeBips,
        address feeRecipient
    ) public payable override {
        require(feeBips > 0 && feeBips <= 100);

        uint256 balanceToken = IERC20(token).balanceOf(address(this));
        require(balanceToken >= amountMinimum, 'Insufficient token');

        if (balanceToken > 0) {
            uint256 feeAmount = balanceToken.mul(feeBips) / 10_000;
            if (feeAmount > 0) TransferHelper.safeTransfer(token, feeRecipient, feeAmount);
            TransferHelper.safeTransfer(token, recipient, balanceToken - feeAmount);
        }
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;

import '../interfaces/IImmutableState.sol';

/// @title Immutable state
/// @notice Immutable state used by the swap router
abstract contract ImmutableState is IImmutableState {
    /// @inheritdoc IImmutableState
    address public immutable override factoryV2;
    /// @inheritdoc IImmutableState
    address public immutable override positionManager;

    constructor(address _factoryV2, address _positionManager) {
        factoryV2 = _factoryV2;
        positionManager = _positionManager;
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Provides functions for deriving a pool address from the factory, tokens, and the fee
library PoolAddress {
    bytes32 internal constant POOL_INIT_CODE_HASH = 0xf42b646464a7fc0f36704e2d2b419f73016e81e8dc1883ae2cc0bd6618708df3;

    /// @notice The identifying key of the pool
    struct PoolKey {
        address token0;
        address token1;
        uint24 fee;
    }

    /// @notice Returns PoolKey: the ordered tokens with the matched fee levels
    /// @param tokenA The first token of a pool, unsorted
    /// @param tokenB The second token of a pool, unsorted
    /// @param fee The fee level of the pool
    /// @return Poolkey The pool details with ordered token0 and token1 assignments
    function getPoolKey(
        address tokenA,
        address tokenB,
        uint24 fee
    ) internal pure returns (PoolKey memory) {
        if (tokenA > tokenB) (tokenA, tokenB) = (tokenB, tokenA);
        return PoolKey({token0: tokenA, token1: tokenB, fee: fee});
    }

    /// @notice Deterministically computes the pool address given the factory and PoolKey
    /// @param factory The ElkDex V3 factory contract address
    /// @param key The PoolKey
    /// @return pool The contract address of the V3 pool
    function computeAddress(address factory, PoolKey memory key) internal pure returns (address pool) {
        require(key.token0 < key.token1);
        pool = address(
            uint256(
                keccak256(
                    abi.encodePacked(
                        hex'ff',
                        factory,
                        keccak256(abi.encode(key.token0, key.token1, key.fee)),
                        POOL_INIT_CODE_HASH
                    )
                )
            )
        );
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;

import '@elkdex/v3-core/contracts/interfaces/IElkDexV3Factory.sol';
import '@elkdex/v3-core/contracts/interfaces/IElkDexV3Pool.sol';

import './PeripheryImmutableState.sol';
import '../interfaces/IPoolInitializer.sol';

/// @title Creates and initializes V3 Pools
abstract contract PoolInitializer is IPoolInitializer, PeripheryImmutableState {
    /// @inheritdoc IPoolInitializer
    function createAndInitializePoolIfNecessary(
        address token0,
        address token1,
        uint24 fee,
        uint160 sqrtPriceX96
    ) external payable override returns (address pool) {
        require(token0 < token1);
        pool = IElkDexV3Factory(factory).getPool(token0, token1, fee);

        if (pool == address(0)) {
            pool = IElkDexV3Factory(factory).createPool(token0, token1, fee);
            IElkDexV3Pool(pool).initialize(sqrtPriceX96);
        } else {
            (uint160 sqrtPriceX96Existing, , , , , , ) = IElkDexV3Pool(pool).slot0();
            if (sqrtPriceX96Existing == 0) {
                IElkDexV3Pool(pool).initialize(sqrtPriceX96);
            }
        }
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;

import '../interfaces/IPeripheryImmutableState.sol';

/// @title Immutable state
/// @notice Immutable state used by periphery contracts
abstract contract PeripheryImmutableState is IPeripheryImmutableState {
    /// @inheritdoc IPeripheryImmutableState
    address public immutable override factory;
    /// @inheritdoc IPeripheryImmutableState
    address public immutable override WETH9;

    constructor(address _factory, address _WETH9) {
        factory = _factory;
        WETH9 = _WETH9;
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

import './pool/IElkDexV3PoolImmutables.sol';
import './pool/IElkDexV3PoolState.sol';
import './pool/IElkDexV3PoolDerivedState.sol';
import './pool/IElkDexV3PoolActions.sol';
import './pool/IElkDexV3PoolOwnerActions.sol';
import './pool/IElkDexV3PoolEvents.sol';

/// @title The interface for a ElkDex V3 Pool
/// @notice A ElkDex pool facilitates swapping and automated market making between any two assets that strictly conform
/// to the ERC20 specification
/// @dev The pool interface is broken up into many smaller pieces
interface IElkDexV3Pool is
    IElkDexV3PoolImmutables,
    IElkDexV3PoolState,
    IElkDexV3PoolDerivedState,
    IElkDexV3PoolActions,
    IElkDexV3PoolOwnerActions,
    IElkDexV3PoolEvents
{

}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

import '@elkdex/v3-core/contracts/interfaces/callback/IElkDexV3SwapCallback.sol';

/// @title Router token swapping functionality
/// @notice Functions for swapping tokens via ElkDex V3
interface ISwapRouter is IElkDexV3SwapCallback {
    struct ExactInputSingleParams {
        address tokenIn;
        address tokenOut;
        uint24 fee;
        address recipient;
        uint256 deadline;
        uint256 amountIn;
        uint256 amountOutMinimum;
        uint160 sqrtPriceLimitX96;
    }

    /// @notice Swaps `amountIn` of one token for as much as possible of another token
    /// @param params The parameters necessary for the swap, encoded as `ExactInputSingleParams` in calldata
    /// @return amountOut The amount of the received token
    function exactInputSingle(ExactInputSingleParams calldata params) external payable returns (uint256 amountOut);

    struct ExactInputParams {
        bytes path;
        address recipient;
        uint256 deadline;
        uint256 amountIn;
        uint256 amountOutMinimum;
    }

    /// @notice Swaps `amountIn` of one token for as much as possible of another along the specified path
    /// @param params The parameters necessary for the multi-hop swap, encoded as `ExactInputParams` in calldata
    /// @return amountOut The amount of the received token
    function exactInput(ExactInputParams calldata params) external payable returns (uint256 amountOut);

    struct ExactOutputSingleParams {
        address tokenIn;
        address tokenOut;
        uint24 fee;
        address recipient;
        uint256 deadline;
        uint256 amountOut;
        uint256 amountInMaximum;
        uint160 sqrtPriceLimitX96;
    }

    /// @notice Swaps as little as possible of one token for `amountOut` of another token
    /// @param params The parameters necessary for the swap, encoded as `ExactOutputSingleParams` in calldata
    /// @return amountIn The amount of the input token
    function exactOutputSingle(ExactOutputSingleParams calldata params) external payable returns (uint256 amountIn);

    struct ExactOutputParams {
        bytes path;
        address recipient;
        uint256 deadline;
        uint256 amountOut;
        uint256 amountInMaximum;
    }

    /// @notice Swaps as little as possible of one token for `amountOut` of another along the specified path (reversed)
    /// @param params The parameters necessary for the multi-hop swap, encoded as `ExactOutputParams` in calldata
    /// @return amountIn The amount of the input token
    function exactOutput(ExactOutputParams calldata params) external payable returns (uint256 amountIn);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

/// @title Tick Lens
/// @notice Provides functions for fetching chunks of tick data for a pool
/// @dev This avoids the waterfall of fetching the tick bitmap, parsing the bitmap to know which ticks to fetch, and
/// then sending additional multicalls to fetch the tick data
interface ITickLens {
    struct PopulatedTick {
        int24 tick;
        int128 liquidityNet;
        uint128 liquidityGross;
    }

    /// @notice Get all the tick data for the populated ticks from a word of the tick bitmap of a pool
    /// @param pool The address of the pool for which to fetch populated tick data
    /// @param tickBitmapIndex The index of the word in the tick bitmap for which to parse the bitmap and
    /// fetch all the populated ticks
    /// @return populatedTicks An array of tick data for the given word in the tick bitmap
    function getPopulatedTicksInWord(address pool, int16 tickBitmapIndex)
        external
        view
        returns (PopulatedTick[] memory populatedTicks);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

import '@elkdex/v3-periphery/contracts/interfaces/IMulticall.sol';

/// @title MulticallExtended interface
/// @notice Enables calling multiple methods in a single call to the contract with optional validation
interface IMulticallExtended is IMulticall {
    /// @notice Call multiple functions in the current contract and return the data from all of them if they all succeed
    /// @dev The `msg.value` should not be trusted for any method callable from multicall.
    /// @param deadline The time by which this function must be called before failing
    /// @param data The encoded function data for each of the calls to make to this contract
    /// @return results The results from each of the calls passed in via data
    function multicall(uint256 deadline, bytes[] calldata data) external payable returns (bytes[] memory results);

    /// @notice Call multiple functions in the current contract and return the data from all of them if they all succeed
    /// @dev The `msg.value` should not be trusted for any method callable from multicall.
    /// @param previousBlockhash The expected parent blockHash
    /// @param data The encoded function data for each of the calls to make to this contract
    /// @return results The results from each of the calls passed in via data
    function multicall(bytes32 previousBlockhash, bytes[] calldata data)
        external
        payable
        returns (bytes[] memory results);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '@elkdex/v3-core/contracts/libraries/LowGasSafeMath.sol';
import '@elkdex/v2-core/contracts/interfaces/IElkDexV2Pair.sol';

import './interfaces/INonfungiblePositionManager.sol';

import './libraries/TransferHelper.sol';

import './interfaces/IV3Migrator.sol';
import './base/PeripheryImmutableState.sol';
import './base/Multicall.sol';
import './base/SelfPermit.sol';
import './interfaces/external/IWETH9.sol';
import './base/PoolInitializer.sol';

/// @title ElkDex V3 Migrator
contract V3Migrator is IV3Migrator, PeripheryImmutableState, PoolInitializer, Multicall, SelfPermit {
    using LowGasSafeMath for uint256;

    address public immutable nonfungiblePositionManager;

    constructor(
        address _factory,
        address _WETH9,
        address _nonfungiblePositionManager
    ) PeripheryImmutableState(_factory, _WETH9) {
        nonfungiblePositionManager = _nonfungiblePositionManager;
    }

    receive() external payable {
        require(msg.sender == WETH9, 'Not WETH9');
    }

    function migrate(MigrateParams calldata params) external override {
        require(params.percentageToMigrate > 0, 'Percentage too small');
        require(params.percentageToMigrate <= 100, 'Percentage too large');

        // burn v2 liquidity to this address
        IElkDexV2Pair(params.pair).transferFrom(msg.sender, params.pair, params.liquidityToMigrate);
        (uint256 amount0V2, uint256 amount1V2) = IElkDexV2Pair(params.pair).burn(address(this));

        // calculate the amounts to migrate to v3
        uint256 amount0V2ToMigrate = amount0V2.mul(params.percentageToMigrate) / 100;
        uint256 amount1V2ToMigrate = amount1V2.mul(params.percentageToMigrate) / 100;

        // approve the position manager up to the maximum token amounts
        TransferHelper.safeApprove(params.token0, nonfungiblePositionManager, amount0V2ToMigrate);
        TransferHelper.safeApprove(params.token1, nonfungiblePositionManager, amount1V2ToMigrate);

        // mint v3 position
        (, , uint256 amount0V3, uint256 amount1V3) =
            INonfungiblePositionManager(nonfungiblePositionManager).mint(
                INonfungiblePositionManager.MintParams({
                    token0: params.token0,
                    token1: params.token1,
                    fee: params.fee,
                    tickLower: params.tickLower,
                    tickUpper: params.tickUpper,
                    amount0Desired: amount0V2ToMigrate,
                    amount1Desired: amount1V2ToMigrate,
                    amount0Min: params.amount0Min,
                    amount1Min: params.amount1Min,
                    recipient: params.recipient,
                    deadline: params.deadline
                })
            );

        // if necessary, clear allowance and refund dust
        if (amount0V3 < amount0V2) {
            if (amount0V3 < amount0V2ToMigrate) {
                TransferHelper.safeApprove(params.token0, nonfungiblePositionManager, 0);
            }

            uint256 refund0 = amount0V2 - amount0V3;
            if (params.refundAsETH && params.token0 == WETH9) {
                IWETH9(WETH9).withdraw(refund0);
                TransferHelper.safeTransferETH(msg.sender, refund0);
            } else {
                TransferHelper.safeTransfer(params.token0, msg.sender, refund0);
            }
        }
        if (amount1V3 < amount1V2) {
            if (amount1V3 < amount1V2ToMigrate) {
                TransferHelper.safeApprove(params.token1, nonfungiblePositionManager, 0);
            }

            uint256 refund1 = amount1V2 - amount1V3;
            if (params.refundAsETH && params.token1 == WETH9) {
                IWETH9(WETH9).withdraw(refund1);
                TransferHelper.safeTransferETH(msg.sender, refund1);
            } else {
                TransferHelper.safeTransfer(params.token1, msg.sender, refund1);
            }
        }
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '@elkdex/v3-periphery/contracts/base/SelfPermit.sol';
import '@elkdex/v3-periphery/contracts/base/PeripheryImmutableState.sol';

import './interfaces/ISwapRouter02.sol';
import './V2SwapRouter.sol';
import './V3SwapRouter.sol';
import './base/ApproveAndCall.sol';
import './base/MulticallExtended.sol';

/// @title ElkDex V2 and V3 Swap Router
contract SwapRouter02 is ISwapRouter02, V2SwapRouter, V3SwapRouter, ApproveAndCall, MulticallExtended, SelfPermit {
    constructor(
        address _factoryV2,
        address factoryV3,
        address _positionManager,
        address _WETH9
    ) ImmutableState(_factoryV2, _positionManager) PeripheryImmutableState(factoryV3, _WETH9) {}
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '@elkdex/v3-core/contracts/libraries/SafeCast.sol';
import '@elkdex/v3-core/contracts/libraries/TickMath.sol';
import '@elkdex/v3-core/contracts/interfaces/IElkDexV3Pool.sol';

import './interfaces/ISwapRouter.sol';
import './base/PeripheryImmutableState.sol';
import './base/PeripheryValidation.sol';
import './base/PeripheryPaymentsWithFee.sol';
import './base/Multicall.sol';
import './base/SelfPermit.sol';
import './libraries/Path.sol';
import './libraries/PoolAddress.sol';
import './libraries/CallbackValidation.sol';
import './interfaces/external/IWETH9.sol';

/// @title ElkDex V3 Swap Router
/// @notice Router for stateless execution of swaps against ElkDex V3
contract SwapRouter is
    ISwapRouter,
    PeripheryImmutableState,
    PeripheryValidation,
    PeripheryPaymentsWithFee,
    Multicall,
    SelfPermit
{
    using Path for bytes;
    using SafeCast for uint256;

    /// @dev Used as the placeholder value for amountInCached, because the computed amount in for an exact output swap
    /// can never actually be this value
    uint256 private constant DEFAULT_AMOUNT_IN_CACHED = type(uint256).max;

    /// @dev Transient storage variable used for returning the computed amount in for an exact output swap.
    uint256 private amountInCached = DEFAULT_AMOUNT_IN_CACHED;

    constructor(address _factory, address _WETH9) PeripheryImmutableState(_factory, _WETH9) {}

    /// @dev Returns the pool for the given token pair and fee. The pool contract may or may not exist.
    function getPool(
        address tokenA,
        address tokenB,
        uint24 fee
    ) private view returns (IElkDexV3Pool) {
        return IElkDexV3Pool(PoolAddress.computeAddress(factory, PoolAddress.getPoolKey(tokenA, tokenB, fee)));
    }

    struct SwapCallbackData {
        bytes path;
        address payer;
    }

    /// @inheritdoc IElkDexV3SwapCallback
    function elkDexV3SwapCallback(
        int256 amount0Delta,
        int256 amount1Delta,
        bytes calldata _data
    ) external override {
        require(amount0Delta > 0 || amount1Delta > 0); // swaps entirely within 0-liquidity regions are not supported
        SwapCallbackData memory data = abi.decode(_data, (SwapCallbackData));
        (address tokenIn, address tokenOut, uint24 fee) = data.path.decodeFirstPool();
        CallbackValidation.verifyCallback(factory, tokenIn, tokenOut, fee);

        (bool isExactInput, uint256 amountToPay) =
            amount0Delta > 0
                ? (tokenIn < tokenOut, uint256(amount0Delta))
                : (tokenOut < tokenIn, uint256(amount1Delta));
        if (isExactInput) {
            pay(tokenIn, data.payer, msg.sender, amountToPay);
        } else {
            // either initiate the next swap or pay
            if (data.path.hasMultiplePools()) {
                data.path = data.path.skipToken();
                exactOutputInternal(amountToPay, msg.sender, 0, data);
            } else {
                amountInCached = amountToPay;
                tokenIn = tokenOut; // swap in/out because exact output swaps are reversed
                pay(tokenIn, data.payer, msg.sender, amountToPay);
            }
        }
    }

    /// @dev Performs a single exact input swap
    function exactInputInternal(
        uint256 amountIn,
        address recipient,
        uint160 sqrtPriceLimitX96,
        SwapCallbackData memory data
    ) private returns (uint256 amountOut) {
        // allow swapping to the router address with address 0
        if (recipient == address(0)) recipient = address(this);

        (address tokenIn, address tokenOut, uint24 fee) = data.path.decodeFirstPool();

        bool zeroForOne = tokenIn < tokenOut;

        (int256 amount0, int256 amount1) =
            getPool(tokenIn, tokenOut, fee).swap(
                recipient,
                zeroForOne,
                amountIn.toInt256(),
                sqrtPriceLimitX96 == 0
                    ? (zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1)
                    : sqrtPriceLimitX96,
                abi.encode(data)
            );

        return uint256(-(zeroForOne ? amount1 : amount0));
    }

    /// @inheritdoc ISwapRouter
    function exactInputSingle(ExactInputSingleParams calldata params)
        external
        payable
        override
        checkDeadline(params.deadline)
        returns (uint256 amountOut)
    {
        amountOut = exactInputInternal(
            params.amountIn,
            params.recipient,
            params.sqrtPriceLimitX96,
            SwapCallbackData({path: abi.encodePacked(params.tokenIn, params.fee, params.tokenOut), payer: msg.sender})
        );
        require(amountOut >= params.amountOutMinimum, 'Too little received');
    }

    /// @inheritdoc ISwapRouter
    function exactInput(ExactInputParams memory params)
        external
        payable
        override
        checkDeadline(params.deadline)
        returns (uint256 amountOut)
    {
        address payer = msg.sender; // msg.sender pays for the first hop

        while (true) {
            bool hasMultiplePools = params.path.hasMultiplePools();

            // the outputs of prior swaps become the inputs to subsequent ones
            params.amountIn = exactInputInternal(
                params.amountIn,
                hasMultiplePools ? address(this) : params.recipient, // for intermediate swaps, this contract custodies
                0,
                SwapCallbackData({
                    path: params.path.getFirstPool(), // only the first pool in the path is necessary
                    payer: payer
                })
            );

            // decide whether to continue or terminate
            if (hasMultiplePools) {
                payer = address(this); // at this point, the caller has paid
                params.path = params.path.skipToken();
            } else {
                amountOut = params.amountIn;
                break;
            }
        }

        require(amountOut >= params.amountOutMinimum, 'Too little received');
    }

    /// @dev Performs a single exact output swap
    function exactOutputInternal(
        uint256 amountOut,
        address recipient,
        uint160 sqrtPriceLimitX96,
        SwapCallbackData memory data
    ) private returns (uint256 amountIn) {
        // allow swapping to the router address with address 0
        if (recipient == address(0)) recipient = address(this);

        (address tokenOut, address tokenIn, uint24 fee) = data.path.decodeFirstPool();

        bool zeroForOne = tokenIn < tokenOut;

        (int256 amount0Delta, int256 amount1Delta) =
            getPool(tokenIn, tokenOut, fee).swap(
                recipient,
                zeroForOne,
                -amountOut.toInt256(),
                sqrtPriceLimitX96 == 0
                    ? (zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1)
                    : sqrtPriceLimitX96,
                abi.encode(data)
            );

        uint256 amountOutReceived;
        (amountIn, amountOutReceived) = zeroForOne
            ? (uint256(amount0Delta), uint256(-amount1Delta))
            : (uint256(amount1Delta), uint256(-amount0Delta));
        // it's technically possible to not receive the full output amount,
        // so if no price limit has been specified, require this possibility away
        if (sqrtPriceLimitX96 == 0) require(amountOutReceived == amountOut);
    }

    /// @inheritdoc ISwapRouter
    function exactOutputSingle(ExactOutputSingleParams calldata params)
        external
        payable
        override
        checkDeadline(params.deadline)
        returns (uint256 amountIn)
    {
        // avoid an SLOAD by using the swap return data
        amountIn = exactOutputInternal(
            params.amountOut,
            params.recipient,
            params.sqrtPriceLimitX96,
            SwapCallbackData({path: abi.encodePacked(params.tokenOut, params.fee, params.tokenIn), payer: msg.sender})
        );

        require(amountIn <= params.amountInMaximum, 'Too much requested');
        // has to be reset even though we don't use it in the single hop case
        amountInCached = DEFAULT_AMOUNT_IN_CACHED;
    }

    /// @inheritdoc ISwapRouter
    function exactOutput(ExactOutputParams calldata params)
        external
        payable
        override
        checkDeadline(params.deadline)
        returns (uint256 amountIn)
    {
        // it's okay that the payer is fixed to msg.sender here, as they're only paying for the "final" exact output
        // swap, which happens first, and subsequent swaps are paid for within nested callback frames
        exactOutputInternal(
            params.amountOut,
            params.recipient,
            0,
            SwapCallbackData({path: params.path, payer: msg.sender})
        );

        amountIn = amountInCached;
        require(amountIn <= params.amountInMaximum, 'Too much requested');
        amountInCached = DEFAULT_AMOUNT_IN_CACHED;
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;

import '@openzeppelin/contracts/token/ERC20/IERC20.sol';

import '../interfaces/IPeripheryPayments.sol';
import '../interfaces/external/IWETH9.sol';

import '../libraries/TransferHelper.sol';

import './PeripheryImmutableState.sol';

abstract contract PeripheryPayments is IPeripheryPayments, PeripheryImmutableState {
    receive() external payable {
        require(msg.sender == WETH9, 'Not WETH9');
    }

    /// @inheritdoc IPeripheryPayments
    function unwrapWETH9(uint256 amountMinimum, address recipient) public payable override {
        uint256 balanceWETH9 = IWETH9(WETH9).balanceOf(address(this));
        require(balanceWETH9 >= amountMinimum, 'Insufficient WETH9');

        if (balanceWETH9 > 0) {
            IWETH9(WETH9).withdraw(balanceWETH9);
            TransferHelper.safeTransferETH(recipient, balanceWETH9);
        }
    }

    /// @inheritdoc IPeripheryPayments
    function sweepToken(
        address token,
        uint256 amountMinimum,
        address recipient
    ) public payable override {
        uint256 balanceToken = IERC20(token).balanceOf(address(this));
        require(balanceToken >= amountMinimum, 'Insufficient token');

        if (balanceToken > 0) {
            TransferHelper.safeTransfer(token, recipient, balanceToken);
        }
    }

    /// @inheritdoc IPeripheryPayments
    function refundETH() external payable override {
        if (address(this).balance > 0) TransferHelper.safeTransferETH(msg.sender, address(this).balance);
    }

    /// @param token The token to pay
    /// @param payer The entity that must pay
    /// @param recipient The entity that will receive payment
    /// @param value The amount to pay
    function pay(
        address token,
        address payer,
        address recipient,
        uint256 value
    ) internal {
        if (token == WETH9 && address(this).balance >= value) {
            // pay with WETH9
            IWETH9(WETH9).deposit{value: value}(); // wrap only what is needed to pay
            IWETH9(WETH9).transfer(recipient, value);
        } else if (payer == address(this)) {
            // pay with tokens already in the contract (for the exact input multihop case)
            TransferHelper.safeTransfer(token, recipient, value);
        } else {
            // pull payment
            TransferHelper.safeTransferFrom(token, payer, recipient, value);
        }
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title The interface for the ElkDex V3 Factory
/// @notice The ElkDex V3 Factory facilitates creation of ElkDex V3 pools and control over the protocol fees
interface IElkDexV3Factory {
    /// @notice Emitted when the owner of the factory is changed
    /// @param oldOwner The owner before the owner was changed
    /// @param newOwner The owner after the owner was changed
    event OwnerChanged(address indexed oldOwner, address indexed newOwner);

    /// @notice Emitted when a pool is created
    /// @param token0 The first token of the pool by address sort order
    /// @param token1 The second token of the pool by address sort order
    /// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
    /// @param tickSpacing The minimum number of ticks between initialized ticks
    /// @param pool The address of the created pool
    event PoolCreated(
        address indexed token0,
        address indexed token1,
        uint24 indexed fee,
        int24 tickSpacing,
        address pool
    );

    /// @notice Emitted when a new fee amount is enabled for pool creation via the factory
    /// @param fee The enabled fee, denominated in hundredths of a bip
    /// @param tickSpacing The minimum number of ticks between initialized ticks for pools created with the given fee
    event FeeAmountEnabled(uint24 indexed fee, int24 indexed tickSpacing);

    /// @notice Returns the current owner of the factory
    /// @dev Can be changed by the current owner via setOwner
    /// @return The address of the factory owner
    function owner() external view returns (address);

    /// @notice Returns the tick spacing for a given fee amount, if enabled, or 0 if not enabled
    /// @dev A fee amount can never be removed, so this value should be hard coded or cached in the calling context
    /// @param fee The enabled fee, denominated in hundredths of a bip. Returns 0 in case of unenabled fee
    /// @return The tick spacing
    function feeAmountTickSpacing(uint24 fee) external view returns (int24);

    /// @notice Returns the pool address for a given pair of tokens and a fee, or address 0 if it does not exist
    /// @dev tokenA and tokenB may be passed in either token0/token1 or token1/token0 order
    /// @param tokenA The contract address of either token0 or token1
    /// @param tokenB The contract address of the other token
    /// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
    /// @return pool The pool address
    function getPool(
        address tokenA,
        address tokenB,
        uint24 fee
    ) external view returns (address pool);

    /// @notice Creates a pool for the given two tokens and fee
    /// @param tokenA One of the two tokens in the desired pool
    /// @param tokenB The other of the two tokens in the desired pool
    /// @param fee The desired fee for the pool
    /// @dev tokenA and tokenB may be passed in either order: token0/token1 or token1/token0. tickSpacing is retrieved
    /// from the fee. The call will revert if the pool already exists, the fee is invalid, or the token arguments
    /// are invalid.
    /// @return pool The address of the newly created pool
    function createPool(
        address tokenA,
        address tokenB,
        uint24 fee
    ) external returns (address pool);

    /// @notice Updates the owner of the factory
    /// @dev Must be called by the current owner
    /// @param _owner The new owner of the factory
    function setOwner(address _owner) external;

    /// @notice Enables a fee amount with the given tickSpacing
    /// @dev Fee amounts may never be removed once enabled
    /// @param fee The fee amount to enable, denominated in hundredths of a bip (i.e. 1e-6)
    /// @param tickSpacing The spacing between ticks to be enforced for all pools created with the given fee amount
    function enableFeeAmount(uint24 fee, int24 tickSpacing) external;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.6.0;

import '@elkdex/v3-core/contracts/interfaces/IElkDexV3Pool.sol';

library PoolTicksCounter {
    /// @dev This function counts the number of initialized ticks that would incur a gas cost between tickBefore and tickAfter.
    /// When tickBefore and/or tickAfter themselves are initialized, the logic over whether we should count them depends on the
    /// direction of the swap. If we are swapping upwards (tickAfter > tickBefore) we don't want to count tickBefore but we do
    /// want to count tickAfter. The opposite is true if we are swapping downwards.
    function countInitializedTicksCrossed(
        IElkDexV3Pool self,
        int24 tickBefore,
        int24 tickAfter
    ) internal view returns (uint32 initializedTicksCrossed) {
        int16 wordPosLower;
        int16 wordPosHigher;
        uint8 bitPosLower;
        uint8 bitPosHigher;
        bool tickBeforeInitialized;
        bool tickAfterInitialized;

        {
            // Get the key and offset in the tick bitmap of the active tick before and after the swap.
            int16 wordPos = int16((tickBefore / self.tickSpacing()) >> 8);
            uint8 bitPos = uint8((tickBefore / self.tickSpacing()) % 256);

            int16 wordPosAfter = int16((tickAfter / self.tickSpacing()) >> 8);
            uint8 bitPosAfter = uint8((tickAfter / self.tickSpacing()) % 256);

            // In the case where tickAfter is initialized, we only want to count it if we are swapping downwards.
            // If the initializable tick after the swap is initialized, our original tickAfter is a
            // multiple of tick spacing, and we are swapping downwards we know that tickAfter is initialized
            // and we shouldn't count it.
            tickAfterInitialized =
                ((self.tickBitmap(wordPosAfter) & (1 << bitPosAfter)) > 0) &&
                ((tickAfter % self.tickSpacing()) == 0) &&
                (tickBefore > tickAfter);

            // In the case where tickBefore is initialized, we only want to count it if we are swapping upwards.
            // Use the same logic as above to decide whether we should count tickBefore or not.
            tickBeforeInitialized =
                ((self.tickBitmap(wordPos) & (1 << bitPos)) > 0) &&
                ((tickBefore % self.tickSpacing()) == 0) &&
                (tickBefore < tickAfter);

            if (wordPos < wordPosAfter || (wordPos == wordPosAfter && bitPos <= bitPosAfter)) {
                wordPosLower = wordPos;
                bitPosLower = bitPos;
                wordPosHigher = wordPosAfter;
                bitPosHigher = bitPosAfter;
            } else {
                wordPosLower = wordPosAfter;
                bitPosLower = bitPosAfter;
                wordPosHigher = wordPos;
                bitPosHigher = bitPos;
            }
        }

        // Count the number of initialized ticks crossed by iterating through the tick bitmap.
        // Our first mask should include the lower tick and everything to its left.
        uint256 mask = type(uint256).max << bitPosLower;
        while (wordPosLower <= wordPosHigher) {
            // If we're on the final tick bitmap page, ensure we only count up to our
            // ending tick.
            if (wordPosLower == wordPosHigher) {
                mask = mask & (type(uint256).max >> (255 - bitPosHigher));
            }

            uint256 masked = self.tickBitmap(wordPosLower) & mask;
            initializedTicksCrossed += countOneBits(masked);
            wordPosLower++;
            // Reset our mask so we consider all bits on the next iteration.
            mask = type(uint256).max;
        }

        if (tickAfterInitialized) {
            initializedTicksCrossed -= 1;
        }

        if (tickBeforeInitialized) {
            initializedTicksCrossed -= 1;
        }

        return initializedTicksCrossed;
    }

    function countOneBits(uint256 x) private pure returns (uint16) {
        uint16 bits = 0;
        while (x != 0) {
            bits++;
            x &= (x - 1);
        }
        return bits;
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Events emitted by a pool
/// @notice Contains all events emitted by the pool
interface IElkDexV3PoolEvents {
    /// @notice Emitted exactly once by a pool when #initialize is first called on the pool
    /// @dev Mint/Burn/Swap cannot be emitted by the pool before Initialize
    /// @param sqrtPriceX96 The initial sqrt price of the pool, as a Q64.96
    /// @param tick The initial tick of the pool, i.e. log base 1.0001 of the starting price of the pool
    event Initialize(uint160 sqrtPriceX96, int24 tick);

    /// @notice Emitted when liquidity is minted for a given position
    /// @param sender The address that minted the liquidity
    /// @param owner The owner of the position and recipient of any minted liquidity
    /// @param tickLower The lower tick of the position
    /// @param tickUpper The upper tick of the position
    /// @param amount The amount of liquidity minted to the position range
    /// @param amount0 How much token0 was required for the minted liquidity
    /// @param amount1 How much token1 was required for the minted liquidity
    event Mint(
        address sender,
        address indexed owner,
        int24 indexed tickLower,
        int24 indexed tickUpper,
        uint128 amount,
        uint256 amount0,
        uint256 amount1
    );

    /// @notice Emitted when fees are collected by the owner of a position
    /// @dev Collect events may be emitted with zero amount0 and amount1 when the caller chooses not to collect fees
    /// @param owner The owner of the position for which fees are collected
    /// @param tickLower The lower tick of the position
    /// @param tickUpper The upper tick of the position
    /// @param amount0 The amount of token0 fees collected
    /// @param amount1 The amount of token1 fees collected
    event Collect(
        address indexed owner,
        address recipient,
        int24 indexed tickLower,
        int24 indexed tickUpper,
        uint128 amount0,
        uint128 amount1
    );

    /// @notice Emitted when a position's liquidity is removed
    /// @dev Does not withdraw any fees earned by the liquidity position, which must be withdrawn via #collect
    /// @param owner The owner of the position for which liquidity is removed
    /// @param tickLower The lower tick of the position
    /// @param tickUpper The upper tick of the position
    /// @param amount The amount of liquidity to remove
    /// @param amount0 The amount of token0 withdrawn
    /// @param amount1 The amount of token1 withdrawn
    event Burn(
        address indexed owner,
        int24 indexed tickLower,
        int24 indexed tickUpper,
        uint128 amount,
        uint256 amount0,
        uint256 amount1
    );

    /// @notice Emitted by the pool for any swaps between token0 and token1
    /// @param sender The address that initiated the swap call, and that received the callback
    /// @param recipient The address that received the output of the swap
    /// @param amount0 The delta of the token0 balance of the pool
    /// @param amount1 The delta of the token1 balance of the pool
    /// @param sqrtPriceX96 The sqrt(price) of the pool after the swap, as a Q64.96
    /// @param liquidity The liquidity of the pool after the swap
    /// @param tick The log base 1.0001 of price of the pool after the swap
    event Swap(
        address indexed sender,
        address indexed recipient,
        int256 amount0,
        int256 amount1,
        uint160 sqrtPriceX96,
        uint128 liquidity,
        int24 tick
    );

    /// @notice Emitted by the pool for any flashes of token0/token1
    /// @param sender The address that initiated the swap call, and that received the callback
    /// @param recipient The address that received the tokens from flash
    /// @param amount0 The amount of token0 that was flashed
    /// @param amount1 The amount of token1 that was flashed
    /// @param paid0 The amount of token0 paid for the flash, which can exceed the amount0 plus the fee
    /// @param paid1 The amount of token1 paid for the flash, which can exceed the amount1 plus the fee
    event Flash(
        address indexed sender,
        address indexed recipient,
        uint256 amount0,
        uint256 amount1,
        uint256 paid0,
        uint256 paid1
    );

    /// @notice Emitted by the pool for increases to the number of observations that can be stored
    /// @dev observationCardinalityNext is not the observation cardinality until an observation is written at the index
    /// just before a mint/swap/burn.
    /// @param observationCardinalityNextOld The previous value of the next observation cardinality
    /// @param observationCardinalityNextNew The updated value of the next observation cardinality
    event IncreaseObservationCardinalityNext(
        uint16 observationCardinalityNextOld,
        uint16 observationCardinalityNextNew
    );

    /// @notice Emitted when the protocol fee is changed by the pool
    /// @param feeProtocol0Old The previous value of the token0 protocol fee
    /// @param feeProtocol1Old The previous value of the token1 protocol fee
    /// @param feeProtocol0New The updated value of the token0 protocol fee
    /// @param feeProtocol1New The updated value of the token1 protocol fee
    event SetFeeProtocol(uint8 feeProtocol0Old, uint8 feeProtocol1Old, uint8 feeProtocol0New, uint8 feeProtocol1New);

    /// @notice Emitted when the collected protocol fees are withdrawn by the factory owner
    /// @param sender The address that collects the protocol fees
    /// @param recipient The address that receives the collected protocol fees
    /// @param amount0 The amount of token0 protocol fees that is withdrawn
    /// @param amount0 The amount of token1 protocol fees that is withdrawn
    event CollectProtocol(address indexed sender, address indexed recipient, uint128 amount0, uint128 amount1);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '@elkdex/v3-core/contracts/libraries/LowGasSafeMath.sol';
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';

import './interfaces/IV2SwapRouter.sol';
import './base/ImmutableState.sol';
import './base/PeripheryPaymentsWithFeeExtended.sol';
import './libraries/Constants.sol';
import './libraries/ElkDexV2Library.sol';

/// @title ElkDex V2 Swap Router
/// @notice Router for stateless execution of swaps against ElkDex V2
abstract contract V2SwapRouter is IV2SwapRouter, ImmutableState, PeripheryPaymentsWithFeeExtended {
    using LowGasSafeMath for uint256;

    // supports fee-on-transfer tokens
    // requires the initial amount to have already been sent to the first pair
    function _swap(address[] memory path, address _to) private {
        for (uint256 i; i < path.length - 1; i++) {
            (address input, address output) = (path[i], path[i + 1]);
            (address token0, ) = ElkDexV2Library.sortTokens(input, output);
            IElkDexV2Pair pair = IElkDexV2Pair(ElkDexV2Library.pairFor(factoryV2, input, output));
            uint256 amountInput;
            uint256 amountOutput;
            // scope to avoid stack too deep errors
            {
                (uint256 reserve0, uint256 reserve1, ) = pair.getReserves();
                (uint256 reserveInput, uint256 reserveOutput) =
                    input == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
                amountInput = IERC20(input).balanceOf(address(pair)).sub(reserveInput);
                amountOutput = ElkDexV2Library.getAmountOut(amountInput, reserveInput, reserveOutput);
            }
            (uint256 amount0Out, uint256 amount1Out) =
                input == token0 ? (uint256(0), amountOutput) : (amountOutput, uint256(0));
            address to = i < path.length - 2 ? ElkDexV2Library.pairFor(factoryV2, output, path[i + 2]) : _to;
            pair.swap(amount0Out, amount1Out, to, new bytes(0));
        }
    }

    /// @inheritdoc IV2SwapRouter
    function swapExactTokensForTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to
    ) external payable override returns (uint256 amountOut) {
        // use amountIn == Constants.CONTRACT_BALANCE as a flag to swap the entire balance of the contract
        bool hasAlreadyPaid;
        if (amountIn == Constants.CONTRACT_BALANCE) {
            hasAlreadyPaid = true;
            amountIn = IERC20(path[0]).balanceOf(address(this));
        }

        pay(
            path[0],
            hasAlreadyPaid ? address(this) : msg.sender,
            ElkDexV2Library.pairFor(factoryV2, path[0], path[1]),
            amountIn
        );

        // find and replace to addresses
        if (to == Constants.MSG_SENDER) to = msg.sender;
        else if (to == Constants.ADDRESS_THIS) to = address(this);

        uint256 balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);

        _swap(path, to);

        amountOut = IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore);
        require(amountOut >= amountOutMin, 'Too little received');
    }

    /// @inheritdoc IV2SwapRouter
    function swapTokensForExactTokens(
        uint256 amountOut,
        uint256 amountInMax,
        address[] calldata path,
        address to
    ) external payable override returns (uint256 amountIn) {
        amountIn = ElkDexV2Library.getAmountsIn(factoryV2, amountOut, path)[0];
        require(amountIn <= amountInMax, 'Too much requested');

        pay(path[0], msg.sender, ElkDexV2Library.pairFor(factoryV2, path[0], path[1]), amountIn);

        // find and replace to addresses
        if (to == Constants.MSG_SENDER) to = msg.sender;
        else if (to == Constants.ADDRESS_THIS) to = address(this);

        _swap(path, to);
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/drafts/IERC20Permit.sol';

import '../interfaces/ISelfPermit.sol';
import '../interfaces/external/IERC20PermitAllowed.sol';

/// @title Self Permit
/// @notice Functionality to call permit on any EIP-2612-compliant token for use in the route
/// @dev These functions are expected to be embedded in multicalls to allow EOAs to approve a contract and call a function
/// that requires an approval in a single transaction.
abstract contract SelfPermit is ISelfPermit {
    /// @inheritdoc ISelfPermit
    function selfPermit(
        address token,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public payable override {
        IERC20Permit(token).permit(msg.sender, address(this), value, deadline, v, r, s);
    }

    /// @inheritdoc ISelfPermit
    function selfPermitIfNecessary(
        address token,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external payable override {
        if (IERC20(token).allowance(msg.sender, address(this)) < value) selfPermit(token, value, deadline, v, r, s);
    }

    /// @inheritdoc ISelfPermit
    function selfPermitAllowed(
        address token,
        uint256 nonce,
        uint256 expiry,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public payable override {
        IERC20PermitAllowed(token).permit(msg.sender, address(this), nonce, expiry, true, v, r, s);
    }

    /// @inheritdoc ISelfPermit
    function selfPermitAllowedIfNecessary(
        address token,
        uint256 nonce,
        uint256 expiry,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external payable override {
        if (IERC20(token).allowance(msg.sender, address(this)) < type(uint256).max)
            selfPermitAllowed(token, nonce, expiry, v, r, s);
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Interface for permit
/// @notice Interface used by DAI/CHAI for permit
interface IERC20PermitAllowed {
    /// @notice Approve the spender to spend some tokens via the holder signature
    /// @dev This is the permit interface used by DAI and CHAI
    /// @param holder The address of the token holder, the token owner
    /// @param spender The address of the token spender
    /// @param nonce The holder's nonce, increases at each call to permit
    /// @param expiry The timestamp at which the permit is no longer valid
    /// @param allowed Boolean that sets approval amount, true for type(uint256).max and false for 0
    /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
    /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
    /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
    function permit(
        address holder,
        address spender,
        uint256 nonce,
        uint256 expiry,
        bool allowed,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

import '@elkdex/v3-periphery/contracts/interfaces/ISelfPermit.sol';

import './IV2SwapRouter.sol';
import './IV3SwapRouter.sol';
import './IApproveAndCall.sol';
import './IMulticallExtended.sol';

/// @title Router token swapping functionality
interface ISwapRouter02 is IV2SwapRouter, IV3SwapRouter, IApproveAndCall, IMulticallExtended, ISelfPermit {

}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Pool state that is not stored
/// @notice Contains view functions to provide information about the pool that is computed rather than stored on the
/// blockchain. The functions here may have variable gas costs.
interface IElkDexV3PoolDerivedState {
    /// @notice Returns the cumulative tick and liquidity as of each timestamp `secondsAgo` from the current block timestamp
    /// @dev To get a time weighted average tick or liquidity-in-range, you must call this with two values, one representing
    /// the beginning of the period and another for the end of the period. E.g., to get the last hour time-weighted average tick,
    /// you must call it with secondsAgos = [3600, 0].
    /// @dev The time weighted average tick represents the geometric time weighted average price of the pool, in
    /// log base sqrt(1.0001) of token1 / token0. The TickMath library can be used to go from a tick value to a ratio.
    /// @param secondsAgos From how long ago each cumulative tick and liquidity value should be returned
    /// @return tickCumulatives Cumulative tick values as of each `secondsAgos` from the current block timestamp
    /// @return secondsPerLiquidityCumulativeX128s Cumulative seconds per liquidity-in-range value as of each `secondsAgos` from the current block
    /// timestamp
    function observe(uint32[] calldata secondsAgos)
        external
        view
        returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s);

    /// @notice Returns a snapshot of the tick cumulative, seconds per liquidity and seconds inside a tick range
    /// @dev Snapshots must only be compared to other snapshots, taken over a period for which a position existed.
    /// I.e., snapshots cannot be compared if a position is not held for the entire period between when the first
    /// snapshot is taken and the second snapshot is taken.
    /// @param tickLower The lower tick of the range
    /// @param tickUpper The upper tick of the range
    /// @return tickCumulativeInside The snapshot of the tick accumulator for the range
    /// @return secondsPerLiquidityInsideX128 The snapshot of seconds per liquidity for the range
    /// @return secondsInside The snapshot of seconds per liquidity for the range
    function snapshotCumulativesInside(int24 tickLower, int24 tickUpper)
        external
        view
        returns (
            int56 tickCumulativeInside,
            uint160 secondsPerLiquidityInsideX128,
            uint32 secondsInside
        );
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

import './IMulticall.sol';
import './ISelfPermit.sol';
import './IPoolInitializer.sol';

/// @title V3 Migrator
/// @notice Enables migration of liqudity from ElkDex v2-compatible pairs into ElkDex v3 pools
interface IV3Migrator is IMulticall, ISelfPermit, IPoolInitializer {
    struct MigrateParams {
        address pair; // the ElkDex v2-compatible pair
        uint256 liquidityToMigrate; // expected to be balanceOf(msg.sender)
        uint8 percentageToMigrate; // represented as a numerator over 100
        address token0;
        address token1;
        uint24 fee;
        int24 tickLower;
        int24 tickUpper;
        uint256 amount0Min; // must be discounted by percentageToMigrate
        uint256 amount1Min; // must be discounted by percentageToMigrate
        address recipient;
        uint256 deadline;
        bool refundAsETH;
    }

    /// @notice Migrates liquidity to v3 by burning v2 liquidity and minting a new position for v3
    /// @dev Slippage protection is enforced via `amount{0,1}Min`, which should be a discount of the expected values of
    /// the maximum amount of v3 liquidity that the v2 liquidity can get. For the special case of migrating to an
    /// out-of-range position, `amount{0,1}Min` may be set to 0, enforcing that the position remains out of range
    /// @param params The params necessary to migrate v2 liquidity, encoded as `MigrateParams` in calldata
    function migrate(MigrateParams calldata params) external;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;

import './BlockTimestamp.sol';

abstract contract PeripheryValidation is BlockTimestamp {
    modifier checkDeadline(uint256 deadline) {
        require(_blockTimestamp() <= deadline, 'Transaction too old');
        _;
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

/// @title Quoter Interface
/// @notice Supports quoting the calculated amounts from exact input or exact output swaps
/// @dev These functions are not marked view because they rely on calling non-view functions and reverting
/// to compute the result. They are also not gas efficient and should not be called on-chain.
interface IQuoter {
    /// @notice Returns the amount out received for a given exact input swap without executing the swap
    /// @param path The path of the swap, i.e. each token pair and the pool fee
    /// @param amountIn The amount of the first token to swap
    /// @return amountOut The amount of the last token that would be received
    function quoteExactInput(bytes memory path, uint256 amountIn) external returns (uint256 amountOut);

    /// @notice Returns the amount out received for a given exact input but for a swap of a single pool
    /// @param tokenIn The token being swapped in
    /// @param tokenOut The token being swapped out
    /// @param fee The fee of the token pool to consider for the pair
    /// @param amountIn The desired input amount
    /// @param sqrtPriceLimitX96 The price limit of the pool that cannot be exceeded by the swap
    /// @return amountOut The amount of `tokenOut` that would be received
    function quoteExactInputSingle(
        address tokenIn,
        address tokenOut,
        uint24 fee,
        uint256 amountIn,
        uint160 sqrtPriceLimitX96
    ) external returns (uint256 amountOut);

    /// @notice Returns the amount in required for a given exact output swap without executing the swap
    /// @param path The path of the swap, i.e. each token pair and the pool fee. Path must be provided in reverse order
    /// @param amountOut The amount of the last token to receive
    /// @return amountIn The amount of first token required to be paid
    function quoteExactOutput(bytes memory path, uint256 amountOut) external returns (uint256 amountIn);

    /// @notice Returns the amount in required to receive the given exact output amount but for a swap of a single pool
    /// @param tokenIn The token being swapped in
    /// @param tokenOut The token being swapped out
    /// @param fee The fee of the token pool to consider for the pair
    /// @param amountOut The desired output amount
    /// @param sqrtPriceLimitX96 The price limit of the pool that cannot be exceeded by the swap
    /// @return amountIn The amount required as the input for the swap in order to receive `amountOut`
    function quoteExactOutputSingle(
        address tokenIn,
        address tokenOut,
        uint24 fee,
        uint256 amountOut,
        uint160 sqrtPriceLimitX96
    ) external returns (uint256 amountIn);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;

import './IPeripheryPayments.sol';

/// @title Periphery Payments
/// @notice Functions to ease deposits and withdrawals of ETH
interface IPeripheryPaymentsWithFee is IPeripheryPayments {
    /// @notice Unwraps the contract's WETH9 balance and sends it to recipient as ETH, with a percentage between
    /// 0 (exclusive), and 1 (inclusive) going to feeRecipient
    /// @dev The amountMinimum parameter prevents malicious contracts from stealing WETH9 from users.
    function unwrapWETH9WithFee(
        uint256 amountMinimum,
        address recipient,
        uint256 feeBips,
        address feeRecipient
    ) external payable;

    /// @notice Transfers the full amount of a token held by this contract to recipient, with a percentage between
    /// 0 (exclusive) and 1 (inclusive) going to feeRecipient
    /// @dev The amountMinimum parameter prevents malicious contracts from stealing the token from users
    function sweepTokenWithFee(
        address token,
        uint256 amountMinimum,
        address recipient,
        uint256 feeBips,
        address feeRecipient
    ) external payable;
}
          

// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

import "../../introspection/IERC165.sol";

/**
 * @dev Required interface of an ERC721 compliant contract.
 */
interface IERC721 is IERC165 {
    /**
     * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
     */
    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
     */
    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
     */
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    /**
     * @dev Returns the number of tokens in ``owner``'s account.
     */
    function balanceOf(address owner) external view returns (uint256 balance);

    /**
     * @dev Returns the owner of the `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function ownerOf(uint256 tokenId) external view returns (address owner);

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
     * are aware of the ERC721 protocol to prevent tokens from being forever locked.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(address from, address to, uint256 tokenId) external;

    /**
     * @dev Transfers `tokenId` token from `from` to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address from, address to, uint256 tokenId) external;

    /**
     * @dev Gives permission to `to` to transfer `tokenId` token to another account.
     * The approval is cleared when the token is transferred.
     *
     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
     *
     * Requirements:
     *
     * - The caller must own the token or be an approved operator.
     * - `tokenId` must exist.
     *
     * Emits an {Approval} event.
     */
    function approve(address to, uint256 tokenId) external;

    /**
     * @dev Returns the account approved for `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function getApproved(uint256 tokenId) external view returns (address operator);

    /**
     * @dev Approve or remove `operator` as an operator for the caller.
     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
     *
     * Requirements:
     *
     * - The `operator` cannot be the caller.
     *
     * Emits an {ApprovalForAll} event.
     */
    function setApprovalForAll(address operator, bool _approved) external;

    /**
     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
     *
     * See {setApprovalForAll}
     */
    function isApprovedForAll(address owner, address operator) external view returns (bool);

    /**
      * @dev Safely transfers `tokenId` token from `from` to `to`.
      *
      * Requirements:
      *
      * - `from` cannot be the zero address.
      * - `to` cannot be the zero address.
      * - `tokenId` token must exist and be owned by `from`.
      * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
      * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
      *
      * Emits a {Transfer} event.
      */
    function safeTransferFrom(address from, address to, uint256 tokenId, bytes calldata data) external;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;

import '@elkdex/v3-periphery/contracts/base/PeripheryPaymentsWithFee.sol';

import '../interfaces/IPeripheryPaymentsWithFeeExtended.sol';
import './PeripheryPaymentsExtended.sol';

abstract contract PeripheryPaymentsWithFeeExtended is
    IPeripheryPaymentsWithFeeExtended,
    PeripheryPaymentsExtended,
    PeripheryPaymentsWithFee
{
    /// @inheritdoc IPeripheryPaymentsWithFeeExtended
    function unwrapWETH9WithFee(
        uint256 amountMinimum,
        uint256 feeBips,
        address feeRecipient
    ) external payable override {
        unwrapWETH9WithFee(amountMinimum, msg.sender, feeBips, feeRecipient);
    }

    /// @inheritdoc IPeripheryPaymentsWithFeeExtended
    function sweepTokenWithFee(
        address token,
        uint256 amountMinimum,
        uint256 feeBips,
        address feeRecipient
    ) external payable override {
        sweepTokenWithFee(token, amountMinimum, msg.sender, feeBips, feeRecipient);
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '../interfaces/IOracleSlippage.sol';

import '@elkdex/v3-periphery/contracts/base/PeripheryImmutableState.sol';
import '@elkdex/v3-periphery/contracts/base/BlockTimestamp.sol';
import '@elkdex/v3-periphery/contracts/libraries/Path.sol';
import '@elkdex/v3-periphery/contracts/libraries/PoolAddress.sol';
import '@elkdex/v3-core/contracts/interfaces/IElkDexV3Pool.sol';
import '@elkdex/v3-periphery/contracts/libraries/OracleLibrary.sol';

abstract contract OracleSlippage is IOracleSlippage, PeripheryImmutableState, BlockTimestamp {
    using Path for bytes;

    /// @dev Returns the tick as of the beginning of the current block, and as of right now, for the given pool.
    function getBlockStartingAndCurrentTick(IElkDexV3Pool pool)
        internal
        view
        returns (int24 blockStartingTick, int24 currentTick)
    {
        uint16 observationIndex;
        uint16 observationCardinality;
        (, currentTick, observationIndex, observationCardinality, , , ) = pool.slot0();

        // 2 observations are needed to reliably calculate the block starting tick
        require(observationCardinality > 1, 'NEO');

        // If the latest observation occurred in the past, then no tick-changing trades have happened in this block
        // therefore the tick in `slot0` is the same as at the beginning of the current block.
        // We don't need to check if this observation is initialized - it is guaranteed to be.
        (uint32 observationTimestamp, int56 tickCumulative, , ) = pool.observations(observationIndex);
        if (observationTimestamp != uint32(_blockTimestamp())) {
            blockStartingTick = currentTick;
        } else {
            uint256 prevIndex = (uint256(observationIndex) + observationCardinality - 1) % observationCardinality;
            (uint32 prevObservationTimestamp, int56 prevTickCumulative, , bool prevInitialized) =
                pool.observations(prevIndex);

            require(prevInitialized, 'ONI');

            uint32 delta = observationTimestamp - prevObservationTimestamp;
            blockStartingTick = int24((tickCumulative - prevTickCumulative) / delta);
        }
    }

    /// @dev Virtual function to get pool addresses that can be overridden in tests.
    function getPoolAddress(
        address tokenA,
        address tokenB,
        uint24 fee
    ) internal view virtual returns (IElkDexV3Pool pool) {
        pool = IElkDexV3Pool(PoolAddress.computeAddress(factory, PoolAddress.getPoolKey(tokenA, tokenB, fee)));
    }

    /// @dev Returns the synthetic time-weighted average tick as of secondsAgo, as well as the current tick,
    /// for the given path. Returned synthetic ticks always represent tokenOut/tokenIn prices,
    /// meaning lower ticks are worse.
    function getSyntheticTicks(bytes memory path, uint32 secondsAgo)
        internal
        view
        returns (int256 syntheticAverageTick, int256 syntheticCurrentTick)
    {
        bool lowerTicksAreWorse;

        uint256 numPools = path.numPools();
        address previousTokenIn;
        for (uint256 i = 0; i < numPools; i++) {
            // this assumes the path is sorted in swap order
            (address tokenIn, address tokenOut, uint24 fee) = path.decodeFirstPool();
            IElkDexV3Pool pool = getPoolAddress(tokenIn, tokenOut, fee);

            // get the average and current ticks for the current pool
            int256 averageTick;
            int256 currentTick;
            if (secondsAgo == 0) {
                // we optimize for the secondsAgo == 0 case, i.e. since the beginning of the block
                (averageTick, currentTick) = getBlockStartingAndCurrentTick(pool);
            } else {
                (averageTick, ) = OracleLibrary.consult(address(pool), secondsAgo);
                (, currentTick, , , , , ) = IElkDexV3Pool(pool).slot0();
            }

            if (i == numPools - 1) {
                // if we're here, this is the last pool in the path, meaning tokenOut represents the
                // destination token. so, if tokenIn < tokenOut, then tokenIn is token0 of the last pool,
                // meaning the current running ticks are going to represent tokenOut/tokenIn prices.
                // so, the lower these prices get, the worse of a price the swap will get
                lowerTicksAreWorse = tokenIn < tokenOut;
            } else {
                // if we're here, we need to iterate over the next pool in the path
                path = path.skipToken();
                previousTokenIn = tokenIn;
            }

            // accumulate the ticks derived from the current pool into the running synthetic ticks,
            // ensuring that intermediate tokens "cancel out"
            bool add = (i == 0) || (previousTokenIn < tokenIn ? tokenIn < tokenOut : tokenOut < tokenIn);
            if (add) {
                syntheticAverageTick += averageTick;
                syntheticCurrentTick += currentTick;
            } else {
                syntheticAverageTick -= averageTick;
                syntheticCurrentTick -= currentTick;
            }
        }

        // flip the sign of the ticks if necessary, to ensure that the lower ticks are always worse
        if (!lowerTicksAreWorse) {
            syntheticAverageTick *= -1;
            syntheticCurrentTick *= -1;
        }
    }

    /// @dev Cast a int256 to a int24, revert on overflow or underflow
    function toInt24(int256 y) private pure returns (int24 z) {
        require((z = int24(y)) == y);
    }

    /// @dev For each passed path, fetches the synthetic time-weighted average tick as of secondsAgo,
    /// as well as the current tick. Then, synthetic ticks from all paths are subjected to a weighted
    /// average, where the weights are the fraction of the total input amount allocated to each path.
    /// Returned synthetic ticks always represent tokenOut/tokenIn prices, meaning lower ticks are worse.
    /// Paths must all start and end in the same token.
    function getSyntheticTicks(
        bytes[] memory paths,
        uint128[] memory amounts,
        uint32 secondsAgo
    ) internal view returns (int256 averageSyntheticAverageTick, int256 averageSyntheticCurrentTick) {
        require(paths.length == amounts.length);

        OracleLibrary.WeightedTickData[] memory weightedSyntheticAverageTicks =
            new OracleLibrary.WeightedTickData[](paths.length);
        OracleLibrary.WeightedTickData[] memory weightedSyntheticCurrentTicks =
            new OracleLibrary.WeightedTickData[](paths.length);

        for (uint256 i = 0; i < paths.length; i++) {
            (int256 syntheticAverageTick, int256 syntheticCurrentTick) = getSyntheticTicks(paths[i], secondsAgo);
            weightedSyntheticAverageTicks[i].tick = toInt24(syntheticAverageTick);
            weightedSyntheticCurrentTicks[i].tick = toInt24(syntheticCurrentTick);
            weightedSyntheticAverageTicks[i].weight = amounts[i];
            weightedSyntheticCurrentTicks[i].weight = amounts[i];
        }

        averageSyntheticAverageTick = OracleLibrary.getWeightedArithmeticMeanTick(weightedSyntheticAverageTicks);
        averageSyntheticCurrentTick = OracleLibrary.getWeightedArithmeticMeanTick(weightedSyntheticCurrentTicks);
    }

    /// @inheritdoc IOracleSlippage
    function checkOracleSlippage(
        bytes memory path,
        uint24 maximumTickDivergence,
        uint32 secondsAgo
    ) external view override {
        (int256 syntheticAverageTick, int256 syntheticCurrentTick) = getSyntheticTicks(path, secondsAgo);
        require(syntheticAverageTick - syntheticCurrentTick < maximumTickDivergence, 'TD');
    }

    /// @inheritdoc IOracleSlippage
    function checkOracleSlippage(
        bytes[] memory paths,
        uint128[] memory amounts,
        uint24 maximumTickDivergence,
        uint32 secondsAgo
    ) external view override {
        (int256 averageSyntheticAverageTick, int256 averageSyntheticCurrentTick) =
            getSyntheticTicks(paths, amounts, secondsAgo);
        require(averageSyntheticAverageTick - averageSyntheticCurrentTick < maximumTickDivergence, 'TD');
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '@elkdex/v3-core/contracts/libraries/SafeCast.sol';
import '@elkdex/v3-core/contracts/libraries/TickMath.sol';
import '@elkdex/v3-core/contracts/interfaces/IElkDexV3Pool.sol';
import '@elkdex/v3-core/contracts/interfaces/callback/IElkDexV3SwapCallback.sol';

import '../interfaces/IQuoter.sol';
import '../base/PeripheryImmutableState.sol';
import '../libraries/Path.sol';
import '../libraries/PoolAddress.sol';
import '../libraries/CallbackValidation.sol';

/// @title Provides quotes for swaps
/// @notice Allows getting the expected amount out or amount in for a given swap without executing the swap
/// @dev These functions are not gas efficient and should _not_ be called on chain. Instead, optimistically execute
/// the swap and check the amounts in the callback.
contract Quoter is IQuoter, IElkDexV3SwapCallback, PeripheryImmutableState {
    using Path for bytes;
    using SafeCast for uint256;

    /// @dev Transient storage variable used to check a safety condition in exact output swaps.
    uint256 private amountOutCached;

    constructor(address _factory, address _WETH9) PeripheryImmutableState(_factory, _WETH9) {}

    function getPool(
        address tokenA,
        address tokenB,
        uint24 fee
    ) private view returns (IElkDexV3Pool) {
        return IElkDexV3Pool(PoolAddress.computeAddress(factory, PoolAddress.getPoolKey(tokenA, tokenB, fee)));
    }

    /// @inheritdoc IElkDexV3SwapCallback
    function elkDexV3SwapCallback(
        int256 amount0Delta,
        int256 amount1Delta,
        bytes memory path
    ) external view override {
        require(amount0Delta > 0 || amount1Delta > 0); // swaps entirely within 0-liquidity regions are not supported
        (address tokenIn, address tokenOut, uint24 fee) = path.decodeFirstPool();
        CallbackValidation.verifyCallback(factory, tokenIn, tokenOut, fee);

        (bool isExactInput, uint256 amountToPay, uint256 amountReceived) =
            amount0Delta > 0
                ? (tokenIn < tokenOut, uint256(amount0Delta), uint256(-amount1Delta))
                : (tokenOut < tokenIn, uint256(amount1Delta), uint256(-amount0Delta));
        if (isExactInput) {
            assembly {
                let ptr := mload(0x40)
                mstore(ptr, amountReceived)
                revert(ptr, 32)
            }
        } else {
            // if the cache has been populated, ensure that the full output amount has been received
            if (amountOutCached != 0) require(amountReceived == amountOutCached);
            assembly {
                let ptr := mload(0x40)
                mstore(ptr, amountToPay)
                revert(ptr, 32)
            }
        }
    }

    /// @dev Parses a revert reason that should contain the numeric quote
    function parseRevertReason(bytes memory reason) private pure returns (uint256) {
        if (reason.length != 32) {
            if (reason.length < 68) revert('Unexpected error');
            assembly {
                reason := add(reason, 0x04)
            }
            revert(abi.decode(reason, (string)));
        }
        return abi.decode(reason, (uint256));
    }

    /// @inheritdoc IQuoter
    function quoteExactInputSingle(
        address tokenIn,
        address tokenOut,
        uint24 fee,
        uint256 amountIn,
        uint160 sqrtPriceLimitX96
    ) public override returns (uint256 amountOut) {
        bool zeroForOne = tokenIn < tokenOut;

        try
            getPool(tokenIn, tokenOut, fee).swap(
                address(this), // address(0) might cause issues with some tokens
                zeroForOne,
                amountIn.toInt256(),
                sqrtPriceLimitX96 == 0
                    ? (zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1)
                    : sqrtPriceLimitX96,
                abi.encodePacked(tokenIn, fee, tokenOut)
            )
        {} catch (bytes memory reason) {
            return parseRevertReason(reason);
        }
    }

    /// @inheritdoc IQuoter
    function quoteExactInput(bytes memory path, uint256 amountIn) external override returns (uint256 amountOut) {
        while (true) {
            bool hasMultiplePools = path.hasMultiplePools();

            (address tokenIn, address tokenOut, uint24 fee) = path.decodeFirstPool();

            // the outputs of prior swaps become the inputs to subsequent ones
            amountIn = quoteExactInputSingle(tokenIn, tokenOut, fee, amountIn, 0);

            // decide whether to continue or terminate
            if (hasMultiplePools) {
                path = path.skipToken();
            } else {
                return amountIn;
            }
        }
    }

    /// @inheritdoc IQuoter
    function quoteExactOutputSingle(
        address tokenIn,
        address tokenOut,
        uint24 fee,
        uint256 amountOut,
        uint160 sqrtPriceLimitX96
    ) public override returns (uint256 amountIn) {
        bool zeroForOne = tokenIn < tokenOut;

        // if no price limit has been specified, cache the output amount for comparison in the swap callback
        if (sqrtPriceLimitX96 == 0) amountOutCached = amountOut;
        try
            getPool(tokenIn, tokenOut, fee).swap(
                address(this), // address(0) might cause issues with some tokens
                zeroForOne,
                -amountOut.toInt256(),
                sqrtPriceLimitX96 == 0
                    ? (zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1)
                    : sqrtPriceLimitX96,
                abi.encodePacked(tokenOut, fee, tokenIn)
            )
        {} catch (bytes memory reason) {
            if (sqrtPriceLimitX96 == 0) delete amountOutCached; // clear cache
            return parseRevertReason(reason);
        }
    }

    /// @inheritdoc IQuoter
    function quoteExactOutput(bytes memory path, uint256 amountOut) external override returns (uint256 amountIn) {
        while (true) {
            bool hasMultiplePools = path.hasMultiplePools();

            (address tokenOut, address tokenIn, uint24 fee) = path.decodeFirstPool();

            // the inputs of prior swaps become the outputs of subsequent ones
            amountOut = quoteExactOutputSingle(tokenIn, tokenOut, fee, amountOut, 0);

            // decide whether to continue or terminate
            if (hasMultiplePools) {
                path = path.skipToken();
            } else {
                return amountOut;
            }
        }
    }
}
          

// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

import "./IERC721.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721Enumerable is IERC721 {

    /**
     * @dev Returns the total amount of tokens stored by the contract.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns a token ID owned by `owner` at a given `index` of its token list.
     * Use along with {balanceOf} to enumerate all of ``owner``'s tokens.
     */
    function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256 tokenId);

    /**
     * @dev Returns a token ID at a given `index` of all the tokens stored by the contract.
     * Use along with {totalSupply} to enumerate all tokens.
     */
    function tokenByIndex(uint256 index) external view returns (uint256);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0 <0.8.0;

/// @title Math library for computing sqrt prices from ticks and vice versa
/// @notice Computes sqrt price for ticks of size 1.0001, i.e. sqrt(1.0001^tick) as fixed point Q64.96 numbers. Supports
/// prices between 2**-128 and 2**128
library TickMath {
    /// @dev The minimum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**-128
    int24 internal constant MIN_TICK = -887272;
    /// @dev The maximum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**128
    int24 internal constant MAX_TICK = -MIN_TICK;

    /// @dev The minimum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MIN_TICK)
    uint160 internal constant MIN_SQRT_RATIO = 4295128739;
    /// @dev The maximum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MAX_TICK)
    uint160 internal constant MAX_SQRT_RATIO = 1461446703485210103287273052203988822378723970342;

    /// @notice Calculates sqrt(1.0001^tick) * 2^96
    /// @dev Throws if |tick| > max tick
    /// @param tick The input tick for the above formula
    /// @return sqrtPriceX96 A Fixed point Q64.96 number representing the sqrt of the ratio of the two assets (token1/token0)
    /// at the given tick
    function getSqrtRatioAtTick(int24 tick) internal pure returns (uint160 sqrtPriceX96) {
        uint256 absTick = tick < 0 ? uint256(-int256(tick)) : uint256(int256(tick));
        require(absTick <= uint256(MAX_TICK), 'T');

        uint256 ratio = absTick & 0x1 != 0 ? 0xfffcb933bd6fad37aa2d162d1a594001 : 0x100000000000000000000000000000000;
        if (absTick & 0x2 != 0) ratio = (ratio * 0xfff97272373d413259a46990580e213a) >> 128;
        if (absTick & 0x4 != 0) ratio = (ratio * 0xfff2e50f5f656932ef12357cf3c7fdcc) >> 128;
        if (absTick & 0x8 != 0) ratio = (ratio * 0xffe5caca7e10e4e61c3624eaa0941cd0) >> 128;
        if (absTick & 0x10 != 0) ratio = (ratio * 0xffcb9843d60f6159c9db58835c926644) >> 128;
        if (absTick & 0x20 != 0) ratio = (ratio * 0xff973b41fa98c081472e6896dfb254c0) >> 128;
        if (absTick & 0x40 != 0) ratio = (ratio * 0xff2ea16466c96a3843ec78b326b52861) >> 128;
        if (absTick & 0x80 != 0) ratio = (ratio * 0xfe5dee046a99a2a811c461f1969c3053) >> 128;
        if (absTick & 0x100 != 0) ratio = (ratio * 0xfcbe86c7900a88aedcffc83b479aa3a4) >> 128;
        if (absTick & 0x200 != 0) ratio = (ratio * 0xf987a7253ac413176f2b074cf7815e54) >> 128;
        if (absTick & 0x400 != 0) ratio = (ratio * 0xf3392b0822b70005940c7a398e4b70f3) >> 128;
        if (absTick & 0x800 != 0) ratio = (ratio * 0xe7159475a2c29b7443b29c7fa6e889d9) >> 128;
        if (absTick & 0x1000 != 0) ratio = (ratio * 0xd097f3bdfd2022b8845ad8f792aa5825) >> 128;
        if (absTick & 0x2000 != 0) ratio = (ratio * 0xa9f746462d870fdf8a65dc1f90e061e5) >> 128;
        if (absTick & 0x4000 != 0) ratio = (ratio * 0x70d869a156d2a1b890bb3df62baf32f7) >> 128;
        if (absTick & 0x8000 != 0) ratio = (ratio * 0x31be135f97d08fd981231505542fcfa6) >> 128;
        if (absTick & 0x10000 != 0) ratio = (ratio * 0x9aa508b5b7a84e1c677de54f3e99bc9) >> 128;
        if (absTick & 0x20000 != 0) ratio = (ratio * 0x5d6af8dedb81196699c329225ee604) >> 128;
        if (absTick & 0x40000 != 0) ratio = (ratio * 0x2216e584f5fa1ea926041bedfe98) >> 128;
        if (absTick & 0x80000 != 0) ratio = (ratio * 0x48a170391f7dc42444e8fa2) >> 128;

        if (tick > 0) ratio = type(uint256).max / ratio;

        // this divides by 1<<32 rounding up to go from a Q128.128 to a Q128.96.
        // we then downcast because we know the result always fits within 160 bits due to our tick input constraint
        // we round up in the division so getTickAtSqrtRatio of the output price is always consistent
        sqrtPriceX96 = uint160((ratio >> 32) + (ratio % (1 << 32) == 0 ? 0 : 1));
    }

    /// @notice Calculates the greatest tick value such that getRatioAtTick(tick) <= ratio
    /// @dev Throws in case sqrtPriceX96 < MIN_SQRT_RATIO, as MIN_SQRT_RATIO is the lowest value getRatioAtTick may
    /// ever return.
    /// @param sqrtPriceX96 The sqrt ratio for which to compute the tick as a Q64.96
    /// @return tick The greatest tick for which the ratio is less than or equal to the input ratio
    function getTickAtSqrtRatio(uint160 sqrtPriceX96) internal pure returns (int24 tick) {
        // second inequality must be < because the price can never reach the price at the max tick
        require(sqrtPriceX96 >= MIN_SQRT_RATIO && sqrtPriceX96 < MAX_SQRT_RATIO, 'R');
        uint256 ratio = uint256(sqrtPriceX96) << 32;

        uint256 r = ratio;
        uint256 msb = 0;

        assembly {
            let f := shl(7, gt(r, 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(6, gt(r, 0xFFFFFFFFFFFFFFFF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(5, gt(r, 0xFFFFFFFF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(4, gt(r, 0xFFFF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(3, gt(r, 0xFF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(2, gt(r, 0xF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(1, gt(r, 0x3))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := gt(r, 0x1)
            msb := or(msb, f)
        }

        if (msb >= 128) r = ratio >> (msb - 127);
        else r = ratio << (127 - msb);

        int256 log_2 = (int256(msb) - 128) << 64;

        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(63, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(62, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(61, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(60, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(59, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(58, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(57, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(56, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(55, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(54, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(53, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(52, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(51, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(50, f))
        }

        int256 log_sqrt10001 = log_2 * 255738958999603826347141; // 128.128 number

        int24 tickLow = int24((log_sqrt10001 - 3402992956809132418596140100660247210) >> 128);
        int24 tickHi = int24((log_sqrt10001 + 291339464771989622907027621153398088495) >> 128);

        tick = tickLow == tickHi ? tickLow : getSqrtRatioAtTick(tickHi) <= sqrtPriceX96 ? tickHi : tickLow;
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

/// @title Multicall interface
/// @notice Enables calling multiple methods in a single call to the contract
interface IMulticall {
    /// @notice Call multiple functions in the current contract and return the data from all of them if they all succeed
    /// @dev The `msg.value` should not be trusted for any method callable from multicall.
    /// @param data The encoded function data for each of the calls to make to this contract
    /// @return results The results from each of the calls passed in via data
    function multicall(bytes[] calldata data) external payable returns (bytes[] memory results);
}
          

// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;

import '@elkdex/v3-core/contracts/interfaces/IElkDexV3Pool.sol';
import './PoolAddress.sol';

/// @notice Provides validation for callbacks from ElkDex V3 Pools
library CallbackValidation {
    /// @notice Returns the address of a valid ElkDex V3 Pool
    /// @param factory The contract address of the ElkDex V3 factory
    /// @param tokenA The contract address of either token0 or token1
    /// @param tokenB The contract address of the other token
    /// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
    /// @return pool The V3 pool contract address
    function verifyCallback(
        address factory,
        address tokenA,
        address tokenB,
        uint24 fee
    ) internal view returns (IElkDexV3Pool pool) {
        return verifyCallback(factory, PoolAddress.getPoolKey(tokenA, tokenB, fee));
    }

    /// @notice Returns the address of a valid ElkDex V3 Pool
    /// @param factory The contract address of the ElkDex V3 factory
    /// @param poolKey The identifying key of the V3 pool
    /// @return pool The V3 pool contract address
    function verifyCallback(address factory, PoolAddress.PoolKey memory poolKey)
        internal
        view
        returns (IElkDexV3Pool pool)
    {
        pool = IElkDexV3Pool(PoolAddress.computeAddress(factory, poolKey));
        require(msg.sender == address(pool));
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * @title Solidity Bytes Arrays Utils
 * @author Gonçalo Sá <[email protected]>
 *
 * @dev Bytes tightly packed arrays utility library for ethereum contracts written in Solidity.
 *      The library lets you concatenate, slice and type cast bytes arrays both in memory and storage.
 */
pragma solidity >=0.5.0 <0.8.0;

library BytesLib {
    function slice(
        bytes memory _bytes,
        uint256 _start,
        uint256 _length
    ) internal pure returns (bytes memory) {
        require(_length + 31 >= _length, 'slice_overflow');
        require(_start + _length >= _start, 'slice_overflow');
        require(_bytes.length >= _start + _length, 'slice_outOfBounds');

        bytes memory tempBytes;

        assembly {
            switch iszero(_length)
                case 0 {
                    // Get a location of some free memory and store it in tempBytes as
                    // Solidity does for memory variables.
                    tempBytes := mload(0x40)

                    // The first word of the slice result is potentially a partial
                    // word read from the original array. To read it, we calculate
                    // the length of that partial word and start copying that many
                    // bytes into the array. The first word we copy will start with
                    // data we don't care about, but the last `lengthmod` bytes will
                    // land at the beginning of the contents of the new array. When
                    // we're done copying, we overwrite the full first word with
                    // the actual length of the slice.
                    let lengthmod := and(_length, 31)

                    // The multiplication in the next line is necessary
                    // because when slicing multiples of 32 bytes (lengthmod == 0)
                    // the following copy loop was copying the origin's length
                    // and then ending prematurely not copying everything it should.
                    let mc := add(add(tempBytes, lengthmod), mul(0x20, iszero(lengthmod)))
                    let end := add(mc, _length)

                    for {
                        // The multiplication in the next line has the same exact purpose
                        // as the one above.
                        let cc := add(add(add(_bytes, lengthmod), mul(0x20, iszero(lengthmod))), _start)
                    } lt(mc, end) {
                        mc := add(mc, 0x20)
                        cc := add(cc, 0x20)
                    } {
                        mstore(mc, mload(cc))
                    }

                    mstore(tempBytes, _length)

                    //update free-memory pointer
                    //allocating the array padded to 32 bytes like the compiler does now
                    mstore(0x40, and(add(mc, 31), not(31)))
                }
                //if we want a zero-length slice let's just return a zero-length array
                default {
                    tempBytes := mload(0x40)
                    //zero out the 32 bytes slice we are about to return
                    //we need to do it because Solidity does not garbage collect
                    mstore(tempBytes, 0)

                    mstore(0x40, add(tempBytes, 0x20))
                }
        }

        return tempBytes;
    }

    function toAddress(bytes memory _bytes, uint256 _start) internal pure returns (address) {
        require(_start + 20 >= _start, 'toAddress_overflow');
        require(_bytes.length >= _start + 20, 'toAddress_outOfBounds');
        address tempAddress;

        assembly {
            tempAddress := div(mload(add(add(_bytes, 0x20), _start)), 0x1000000000000000000000000)
        }

        return tempAddress;
    }

    function toUint24(bytes memory _bytes, uint256 _start) internal pure returns (uint24) {
        require(_start + 3 >= _start, 'toUint24_overflow');
        require(_bytes.length >= _start + 3, 'toUint24_outOfBounds');
        uint24 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x3), _start))
        }

        return tempUint;
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Safe casting methods
/// @notice Contains methods for safely casting between types
library SafeCast {
    /// @notice Cast a uint256 to a uint160, revert on overflow
    /// @param y The uint256 to be downcasted
    /// @return z The downcasted integer, now type uint160
    function toUint160(uint256 y) internal pure returns (uint160 z) {
        require((z = uint160(y)) == y);
    }

    /// @notice Cast a int256 to a int128, revert on overflow or underflow
    /// @param y The int256 to be downcasted
    /// @return z The downcasted integer, now type int128
    function toInt128(int256 y) internal pure returns (int128 z) {
        require((z = int128(y)) == y);
    }

    /// @notice Cast a uint256 to a int256, revert on overflow
    /// @param y The uint256 to be casted
    /// @return z The casted integer, now type int256
    function toInt256(uint256 y) internal pure returns (int256 z) {
        require(y < 2**255);
        z = int256(y);
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

/// @title OracleSlippage interface
/// @notice Enables slippage checks against oracle prices
interface IOracleSlippage {
    /// @notice Ensures that the current (synthetic) tick over the path is no worse than
    /// `maximumTickDivergence` ticks away from the average as of `secondsAgo`
    /// @param path The path to fetch prices over
    /// @param maximumTickDivergence The maximum number of ticks that the price can degrade by
    /// @param secondsAgo The number of seconds ago to compute oracle prices against
    function checkOracleSlippage(
        bytes memory path,
        uint24 maximumTickDivergence,
        uint32 secondsAgo
    ) external view;

    /// @notice Ensures that the weighted average current (synthetic) tick over the path is no
    /// worse than `maximumTickDivergence` ticks away from the average as of `secondsAgo`
    /// @param paths The paths to fetch prices over
    /// @param amounts The weights for each entry in `paths`
    /// @param maximumTickDivergence The maximum number of ticks that the price can degrade by
    /// @param secondsAgo The number of seconds ago to compute oracle prices against
    function checkOracleSlippage(
        bytes[] memory paths,
        uint128[] memory amounts,
        uint24 maximumTickDivergence,
        uint32 secondsAgo
    ) external view;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;

/// @title Constant state
/// @notice Constant state used by the swap router
library Constants {
    /// @dev Used for identifying cases when this contract's balance of a token is to be used
    uint256 internal constant CONTRACT_BALANCE = 0;

    /// @dev Used as a flag for identifying msg.sender, saves gas by sending more 0 bytes
    address internal constant MSG_SENDER = address(1);

    /// @dev Used as a flag for identifying address(this), saves gas by sending more 0 bytes
    address internal constant ADDRESS_THIS = address(2);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '@elkdex/v3-periphery/contracts/base/PeripheryImmutableState.sol';
import '@elkdex/v3-core/contracts/libraries/SafeCast.sol';
import '@elkdex/v3-core/contracts/libraries/TickMath.sol';
import '@elkdex/v3-core/contracts/libraries/TickBitmap.sol';
import '@elkdex/v3-core/contracts/interfaces/IElkDexV3Pool.sol';
import '@elkdex/v3-core/contracts/interfaces/callback/IElkDexV3SwapCallback.sol';
import '@elkdex/v3-periphery/contracts/libraries/Path.sol';
import '@elkdex/v3-periphery/contracts/libraries/PoolAddress.sol';
import '@elkdex/v3-periphery/contracts/libraries/CallbackValidation.sol';

import '../interfaces/IQuoterV2.sol';
import '../libraries/PoolTicksCounter.sol';

/// @title Provides quotes for swaps
/// @notice Allows getting the expected amount out or amount in for a given swap without executing the swap
/// @dev These functions are not gas efficient and should _not_ be called on chain. Instead, optimistically execute
/// the swap and check the amounts in the callback.
contract QuoterV2 is IQuoterV2, IElkDexV3SwapCallback, PeripheryImmutableState {
    using Path for bytes;
    using SafeCast for uint256;
    using PoolTicksCounter for IElkDexV3Pool;

    /// @dev Transient storage variable used to check a safety condition in exact output swaps.
    uint256 private amountOutCached;

    constructor(address _factory, address _WETH9) PeripheryImmutableState(_factory, _WETH9) {}

    function getPool(
        address tokenA,
        address tokenB,
        uint24 fee
    ) private view returns (IElkDexV3Pool) {
        return IElkDexV3Pool(PoolAddress.computeAddress(factory, PoolAddress.getPoolKey(tokenA, tokenB, fee)));
    }

    /// @inheritdoc IElkDexV3SwapCallback
    function elkDexV3SwapCallback(
        int256 amount0Delta,
        int256 amount1Delta,
        bytes memory path
    ) external view override {
        require(amount0Delta > 0 || amount1Delta > 0); // swaps entirely within 0-liquidity regions are not supported
        (address tokenIn, address tokenOut, uint24 fee) = path.decodeFirstPool();
        CallbackValidation.verifyCallback(factory, tokenIn, tokenOut, fee);

        (bool isExactInput, uint256 amountToPay, uint256 amountReceived) =
            amount0Delta > 0
                ? (tokenIn < tokenOut, uint256(amount0Delta), uint256(-amount1Delta))
                : (tokenOut < tokenIn, uint256(amount1Delta), uint256(-amount0Delta));

        IElkDexV3Pool pool = getPool(tokenIn, tokenOut, fee);
        (uint160 sqrtPriceX96After, int24 tickAfter, , , , , ) = pool.slot0();

        if (isExactInput) {
            assembly {
                let ptr := mload(0x40)
                mstore(ptr, amountReceived)
                mstore(add(ptr, 0x20), sqrtPriceX96After)
                mstore(add(ptr, 0x40), tickAfter)
                revert(ptr, 96)
            }
        } else {
            // if the cache has been populated, ensure that the full output amount has been received
            if (amountOutCached != 0) require(amountReceived == amountOutCached);
            assembly {
                let ptr := mload(0x40)
                mstore(ptr, amountToPay)
                mstore(add(ptr, 0x20), sqrtPriceX96After)
                mstore(add(ptr, 0x40), tickAfter)
                revert(ptr, 96)
            }
        }
    }

    /// @dev Parses a revert reason that should contain the numeric quote
    function parseRevertReason(bytes memory reason)
        private
        pure
        returns (
            uint256 amount,
            uint160 sqrtPriceX96After,
            int24 tickAfter
        )
    {
        if (reason.length != 96) {
            if (reason.length < 68) revert('Unexpected error');
            assembly {
                reason := add(reason, 0x04)
            }
            revert(abi.decode(reason, (string)));
        }
        return abi.decode(reason, (uint256, uint160, int24));
    }

    function handleRevert(
        bytes memory reason,
        IElkDexV3Pool pool,
        uint256 gasEstimate
    )
        private
        view
        returns (
            uint256 amount,
            uint160 sqrtPriceX96After,
            uint32 initializedTicksCrossed,
            uint256
        )
    {
        int24 tickBefore;
        int24 tickAfter;
        (, tickBefore, , , , , ) = pool.slot0();
        (amount, sqrtPriceX96After, tickAfter) = parseRevertReason(reason);

        initializedTicksCrossed = pool.countInitializedTicksCrossed(tickBefore, tickAfter);

        return (amount, sqrtPriceX96After, initializedTicksCrossed, gasEstimate);
    }

    function quoteExactInputSingle(QuoteExactInputSingleParams memory params)
        public
        override
        returns (
            uint256 amountOut,
            uint160 sqrtPriceX96After,
            uint32 initializedTicksCrossed,
            uint256 gasEstimate
        )
    {
        bool zeroForOne = params.tokenIn < params.tokenOut;
        IElkDexV3Pool pool = getPool(params.tokenIn, params.tokenOut, params.fee);

        uint256 gasBefore = gasleft();
        try
            pool.swap(
                address(this), // address(0) might cause issues with some tokens
                zeroForOne,
                params.amountIn.toInt256(),
                params.sqrtPriceLimitX96 == 0
                    ? (zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1)
                    : params.sqrtPriceLimitX96,
                abi.encodePacked(params.tokenIn, params.fee, params.tokenOut)
            )
        {} catch (bytes memory reason) {
            gasEstimate = gasBefore - gasleft();
            return handleRevert(reason, pool, gasEstimate);
        }
    }

    function quoteExactInput(bytes memory path, uint256 amountIn)
        public
        override
        returns (
            uint256 amountOut,
            uint160[] memory sqrtPriceX96AfterList,
            uint32[] memory initializedTicksCrossedList,
            uint256 gasEstimate
        )
    {
        sqrtPriceX96AfterList = new uint160[](path.numPools());
        initializedTicksCrossedList = new uint32[](path.numPools());

        uint256 i = 0;
        while (true) {
            (address tokenIn, address tokenOut, uint24 fee) = path.decodeFirstPool();

            // the outputs of prior swaps become the inputs to subsequent ones
            (uint256 _amountOut, uint160 _sqrtPriceX96After, uint32 _initializedTicksCrossed, uint256 _gasEstimate) =
                quoteExactInputSingle(
                    QuoteExactInputSingleParams({
                        tokenIn: tokenIn,
                        tokenOut: tokenOut,
                        fee: fee,
                        amountIn: amountIn,
                        sqrtPriceLimitX96: 0
                    })
                );

            sqrtPriceX96AfterList[i] = _sqrtPriceX96After;
            initializedTicksCrossedList[i] = _initializedTicksCrossed;
            amountIn = _amountOut;
            gasEstimate += _gasEstimate;
            i++;

            // decide whether to continue or terminate
            if (path.hasMultiplePools()) {
                path = path.skipToken();
            } else {
                return (amountIn, sqrtPriceX96AfterList, initializedTicksCrossedList, gasEstimate);
            }
        }
    }

    function quoteExactOutputSingle(QuoteExactOutputSingleParams memory params)
        public
        override
        returns (
            uint256 amountIn,
            uint160 sqrtPriceX96After,
            uint32 initializedTicksCrossed,
            uint256 gasEstimate
        )
    {
        bool zeroForOne = params.tokenIn < params.tokenOut;
        IElkDexV3Pool pool = getPool(params.tokenIn, params.tokenOut, params.fee);

        // if no price limit has been specified, cache the output amount for comparison in the swap callback
        if (params.sqrtPriceLimitX96 == 0) amountOutCached = params.amount;
        uint256 gasBefore = gasleft();
        try
            pool.swap(
                address(this), // address(0) might cause issues with some tokens
                zeroForOne,
                -params.amount.toInt256(),
                params.sqrtPriceLimitX96 == 0
                    ? (zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1)
                    : params.sqrtPriceLimitX96,
                abi.encodePacked(params.tokenOut, params.fee, params.tokenIn)
            )
        {} catch (bytes memory reason) {
            gasEstimate = gasBefore - gasleft();
            if (params.sqrtPriceLimitX96 == 0) delete amountOutCached; // clear cache
            return handleRevert(reason, pool, gasEstimate);
        }
    }

    function quoteExactOutput(bytes memory path, uint256 amountOut)
        public
        override
        returns (
            uint256 amountIn,
            uint160[] memory sqrtPriceX96AfterList,
            uint32[] memory initializedTicksCrossedList,
            uint256 gasEstimate
        )
    {
        sqrtPriceX96AfterList = new uint160[](path.numPools());
        initializedTicksCrossedList = new uint32[](path.numPools());

        uint256 i = 0;
        while (true) {
            (address tokenOut, address tokenIn, uint24 fee) = path.decodeFirstPool();

            // the inputs of prior swaps become the outputs of subsequent ones
            (uint256 _amountIn, uint160 _sqrtPriceX96After, uint32 _initializedTicksCrossed, uint256 _gasEstimate) =
                quoteExactOutputSingle(
                    QuoteExactOutputSingleParams({
                        tokenIn: tokenIn,
                        tokenOut: tokenOut,
                        amount: amountOut,
                        fee: fee,
                        sqrtPriceLimitX96: 0
                    })
                );

            sqrtPriceX96AfterList[i] = _sqrtPriceX96After;
            initializedTicksCrossedList[i] = _initializedTicksCrossed;
            amountOut = _amountIn;
            gasEstimate += _gasEstimate;
            i++;

            // decide whether to continue or terminate
            if (path.hasMultiplePools()) {
                path = path.skipToken();
            } else {
                return (amountOut, sqrtPriceX96AfterList, initializedTicksCrossedList, gasEstimate);
            }
        }
    }
}
          

// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0;

import './BitMath.sol';

/// @title Packed tick initialized state library
/// @notice Stores a packed mapping of tick index to its initialized state
/// @dev The mapping uses int16 for keys since ticks are represented as int24 and there are 256 (2^8) values per word.
library TickBitmap {
    /// @notice Computes the position in the mapping where the initialized bit for a tick lives
    /// @param tick The tick for which to compute the position
    /// @return wordPos The key in the mapping containing the word in which the bit is stored
    /// @return bitPos The bit position in the word where the flag is stored
    function position(int24 tick) private pure returns (int16 wordPos, uint8 bitPos) {
        wordPos = int16(tick >> 8);
        bitPos = uint8(tick % 256);
    }

    /// @notice Flips the initialized state for a given tick from false to true, or vice versa
    /// @param self The mapping in which to flip the tick
    /// @param tick The tick to flip
    /// @param tickSpacing The spacing between usable ticks
    function flipTick(
        mapping(int16 => uint256) storage self,
        int24 tick,
        int24 tickSpacing
    ) internal {
        require(tick % tickSpacing == 0); // ensure that the tick is spaced
        (int16 wordPos, uint8 bitPos) = position(tick / tickSpacing);
        uint256 mask = 1 << bitPos;
        self[wordPos] ^= mask;
    }

    /// @notice Returns the next initialized tick contained in the same word (or adjacent word) as the tick that is either
    /// to the left (less than or equal to) or right (greater than) of the given tick
    /// @param self The mapping in which to compute the next initialized tick
    /// @param tick The starting tick
    /// @param tickSpacing The spacing between usable ticks
    /// @param lte Whether to search for the next initialized tick to the left (less than or equal to the starting tick)
    /// @return next The next initialized or uninitialized tick up to 256 ticks away from the current tick
    /// @return initialized Whether the next tick is initialized, as the function only searches within up to 256 ticks
    function nextInitializedTickWithinOneWord(
        mapping(int16 => uint256) storage self,
        int24 tick,
        int24 tickSpacing,
        bool lte
    ) internal view returns (int24 next, bool initialized) {
        int24 compressed = tick / tickSpacing;
        if (tick < 0 && tick % tickSpacing != 0) compressed--; // round towards negative infinity

        if (lte) {
            (int16 wordPos, uint8 bitPos) = position(compressed);
            // all the 1s at or to the right of the current bitPos
            uint256 mask = (1 << bitPos) - 1 + (1 << bitPos);
            uint256 masked = self[wordPos] & mask;

            // if there are no initialized ticks to the right of or at the current tick, return rightmost in the word
            initialized = masked != 0;
            // overflow/underflow is possible, but prevented externally by limiting both tickSpacing and tick
            next = initialized
                ? (compressed - int24(bitPos - BitMath.mostSignificantBit(masked))) * tickSpacing
                : (compressed - int24(bitPos)) * tickSpacing;
        } else {
            // start from the word of the next tick, since the current tick state doesn't matter
            (int16 wordPos, uint8 bitPos) = position(compressed + 1);
            // all the 1s at or to the left of the bitPos
            uint256 mask = ~((1 << bitPos) - 1);
            uint256 masked = self[wordPos] & mask;

            // if there are no initialized ticks to the left of the current tick, return leftmost in the word
            initialized = masked != 0;
            // overflow/underflow is possible, but prevented externally by limiting both tickSpacing and tick
            next = initialized
                ? (compressed + 1 + int24(BitMath.leastSignificantBit(masked) - bitPos)) * tickSpacing
                : (compressed + 1 + int24(type(uint8).max - bitPos)) * tickSpacing;
        }
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

import '@elkdex/v2-core/contracts/interfaces/IElkDexV2Pair.sol';
import '@elkdex/v3-core/contracts/libraries/LowGasSafeMath.sol';

library ElkDexV2Library {
    using LowGasSafeMath for uint256;

    // returns sorted token addresses, used to handle return values from pairs sorted in this order
    function sortTokens(address tokenA, address tokenB) internal pure returns (address token0, address token1) {
        require(tokenA != tokenB);
        (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
        require(token0 != address(0));
    }

    // calculates the CREATE2 address for a pair without making any external calls
    function pairFor(
        address factory,
        address tokenA,
        address tokenB
    ) internal pure returns (address pair) {
        (address token0, address token1) = sortTokens(tokenA, tokenB);
        pair = address(
            uint256(
                keccak256(
                    abi.encodePacked(
                        hex'ff',
                        factory,
                        keccak256(abi.encodePacked(token0, token1)),
                        hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash
                    )
                )
            )
        );
    }

    // fetches and sorts the reserves for a pair
    function getReserves(
        address factory,
        address tokenA,
        address tokenB
    ) internal view returns (uint256 reserveA, uint256 reserveB) {
        (address token0, ) = sortTokens(tokenA, tokenB);
        (uint256 reserve0, uint256 reserve1, ) = IElkDexV2Pair(pairFor(factory, tokenA, tokenB)).getReserves();
        (reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
    }

    // given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset
    function getAmountOut(
        uint256 amountIn,
        uint256 reserveIn,
        uint256 reserveOut
    ) internal pure returns (uint256 amountOut) {
        require(amountIn > 0, 'INSUFFICIENT_INPUT_AMOUNT');
        require(reserveIn > 0 && reserveOut > 0);
        uint256 amountInWithFee = amountIn.mul(997);
        uint256 numerator = amountInWithFee.mul(reserveOut);
        uint256 denominator = reserveIn.mul(1000).add(amountInWithFee);
        amountOut = numerator / denominator;
    }

    // given an output amount of an asset and pair reserves, returns a required input amount of the other asset
    function getAmountIn(
        uint256 amountOut,
        uint256 reserveIn,
        uint256 reserveOut
    ) internal pure returns (uint256 amountIn) {
        require(amountOut > 0, 'INSUFFICIENT_OUTPUT_AMOUNT');
        require(reserveIn > 0 && reserveOut > 0);
        uint256 numerator = reserveIn.mul(amountOut).mul(1000);
        uint256 denominator = reserveOut.sub(amountOut).mul(997);
        amountIn = (numerator / denominator).add(1);
    }

    // performs chained getAmountIn calculations on any number of pairs
    function getAmountsIn(
        address factory,
        uint256 amountOut,
        address[] memory path
    ) internal view returns (uint256[] memory amounts) {
        require(path.length >= 2);
        amounts = new uint256[](path.length);
        amounts[amounts.length - 1] = amountOut;
        for (uint256 i = path.length - 1; i > 0; i--) {
            (uint256 reserveIn, uint256 reserveOut) = getReserves(factory, path[i - 1], path[i]);
            amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut);
        }
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

interface IApproveAndCall {
    enum ApprovalType {NOT_REQUIRED, MAX, MAX_MINUS_ONE, ZERO_THEN_MAX, ZERO_THEN_MAX_MINUS_ONE}

    /// @dev Lens to be called off-chain to determine which (if any) of the relevant approval functions should be called
    /// @param token The token to approve
    /// @param amount The amount to approve
    /// @return The required approval type
    function getApprovalType(address token, uint256 amount) external returns (ApprovalType);

    /// @notice Approves a token for the maximum possible amount
    /// @param token The token to approve
    function approveMax(address token) external payable;

    /// @notice Approves a token for the maximum possible amount minus one
    /// @param token The token to approve
    function approveMaxMinusOne(address token) external payable;

    /// @notice Approves a token for zero, then the maximum possible amount
    /// @param token The token to approve
    function approveZeroThenMax(address token) external payable;

    /// @notice Approves a token for zero, then the maximum possible amount minus one
    /// @param token The token to approve
    function approveZeroThenMaxMinusOne(address token) external payable;

    /// @notice Calls the position manager with arbitrary calldata
    /// @param data Calldata to pass along to the position manager
    /// @return result The result from the call
    function callPositionManager(bytes memory data) external payable returns (bytes memory result);

    struct MintParams {
        address token0;
        address token1;
        uint24 fee;
        int24 tickLower;
        int24 tickUpper;
        uint256 amount0Min;
        uint256 amount1Min;
        address recipient;
    }

    /// @notice Calls the position manager's mint function
    /// @param params Calldata to pass along to the position manager
    /// @return result The result from the call
    function mint(MintParams calldata params) external payable returns (bytes memory result);

    struct IncreaseLiquidityParams {
        address token0;
        address token1;
        uint256 tokenId;
        uint256 amount0Min;
        uint256 amount1Min;
    }

    /// @notice Calls the position manager's increaseLiquidity function
    /// @param params Calldata to pass along to the position manager
    /// @return result The result from the call
    function increaseLiquidity(IncreaseLiquidityParams calldata params) external payable returns (bytes memory result);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;

import '@elkdex/v3-periphery/contracts/interfaces/IPeripheryPaymentsWithFee.sol';

import './IPeripheryPaymentsExtended.sol';

/// @title Periphery Payments With Fee Extended
/// @notice Functions to ease deposits and withdrawals of ETH
interface IPeripheryPaymentsWithFeeExtended is IPeripheryPaymentsExtended, IPeripheryPaymentsWithFee {
    /// @notice Unwraps the contract's WETH9 balance and sends it to msg.sender as ETH, with a percentage between
    /// 0 (exclusive), and 1 (inclusive) going to feeRecipient
    /// @dev The amountMinimum parameter prevents malicious contracts from stealing WETH9 from users.
    function unwrapWETH9WithFee(
        uint256 amountMinimum,
        uint256 feeBips,
        address feeRecipient
    ) external payable;

    /// @notice Transfers the full amount of a token held by this contract to msg.sender, with a percentage between
    /// 0 (exclusive) and 1 (inclusive) going to feeRecipient
    /// @dev The amountMinimum parameter prevents malicious contracts from stealing the token from users
    function sweepTokenWithFee(
        address token,
        uint256 amountMinimum,
        uint256 feeBips,
        address feeRecipient
    ) external payable;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;

import '@elkdex/v3-periphery/contracts/interfaces/IPeripheryPayments.sol';

/// @title Periphery Payments Extended
/// @notice Functions to ease deposits and withdrawals of ETH and tokens
interface IPeripheryPaymentsExtended is IPeripheryPayments {
    /// @notice Unwraps the contract's WETH9 balance and sends it to msg.sender as ETH.
    /// @dev The amountMinimum parameter prevents malicious contracts from stealing WETH9 from users.
    /// @param amountMinimum The minimum amount of WETH9 to unwrap
    function unwrapWETH9(uint256 amountMinimum) external payable;

    /// @notice Wraps the contract's ETH balance into WETH9
    /// @dev The resulting WETH9 is custodied by the router, thus will require further distribution
    /// @param value The amount of ETH to wrap
    function wrapETH(uint256 value) external payable;

    /// @notice Transfers the full amount of a token held by this contract to msg.sender
    /// @dev The amountMinimum parameter prevents malicious contracts from stealing the token from users
    /// @param token The contract address of the token which will be transferred to msg.sender
    /// @param amountMinimum The minimum amount of token required for a transfer
    function sweepToken(address token, uint256 amountMinimum) external payable;

    /// @notice Transfers the specified amount of a token from the msg.sender to address(this)
    /// @param token The token to pull
    /// @param value The amount to pay
    function pull(address token, uint256 value) external payable;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@elkdex/v3-periphery/contracts/interfaces/INonfungiblePositionManager.sol';

import '../interfaces/IApproveAndCall.sol';
import './ImmutableState.sol';

/// @title Approve and Call
/// @notice Allows callers to approve the ElkDex V3 position manager from this contract,
/// for any token, and then make calls into the position manager
abstract contract ApproveAndCall is IApproveAndCall, ImmutableState {
    function tryApprove(address token, uint256 amount) private returns (bool) {
        (bool success, bytes memory data) =
            token.call(abi.encodeWithSelector(IERC20.approve.selector, positionManager, amount));
        return success && (data.length == 0 || abi.decode(data, (bool)));
    }

    /// @inheritdoc IApproveAndCall
    function getApprovalType(address token, uint256 amount) external override returns (ApprovalType) {
        // check existing approval
        if (IERC20(token).allowance(address(this), positionManager) >= amount) return ApprovalType.NOT_REQUIRED;

        // try type(uint256).max / type(uint256).max - 1
        if (tryApprove(token, type(uint256).max)) return ApprovalType.MAX;
        if (tryApprove(token, type(uint256).max - 1)) return ApprovalType.MAX_MINUS_ONE;

        // set approval to 0 (must succeed)
        require(tryApprove(token, 0));

        // try type(uint256).max / type(uint256).max - 1
        if (tryApprove(token, type(uint256).max)) return ApprovalType.ZERO_THEN_MAX;
        if (tryApprove(token, type(uint256).max - 1)) return ApprovalType.ZERO_THEN_MAX_MINUS_ONE;

        revert();
    }

    /// @inheritdoc IApproveAndCall
    function approveMax(address token) external payable override {
        require(tryApprove(token, type(uint256).max));
    }

    /// @inheritdoc IApproveAndCall
    function approveMaxMinusOne(address token) external payable override {
        require(tryApprove(token, type(uint256).max - 1));
    }

    /// @inheritdoc IApproveAndCall
    function approveZeroThenMax(address token) external payable override {
        require(tryApprove(token, 0));
        require(tryApprove(token, type(uint256).max));
    }

    /// @inheritdoc IApproveAndCall
    function approveZeroThenMaxMinusOne(address token) external payable override {
        require(tryApprove(token, 0));
        require(tryApprove(token, type(uint256).max - 1));
    }

    /// @inheritdoc IApproveAndCall
    function callPositionManager(bytes memory data) public payable override returns (bytes memory result) {
        bool success;
        (success, result) = positionManager.call(data);

        if (!success) {
            // Next 5 lines from https://ethereum.stackexchange.com/a/83577
            if (result.length < 68) revert();
            assembly {
                result := add(result, 0x04)
            }
            revert(abi.decode(result, (string)));
        }
    }

    function balanceOf(address token) private view returns (uint256) {
        return IERC20(token).balanceOf(address(this));
    }

    /// @inheritdoc IApproveAndCall
    function mint(MintParams calldata params) external payable override returns (bytes memory result) {
        return
            callPositionManager(
                abi.encodeWithSelector(
                    INonfungiblePositionManager.mint.selector,
                    INonfungiblePositionManager.MintParams({
                        token0: params.token0,
                        token1: params.token1,
                        fee: params.fee,
                        tickLower: params.tickLower,
                        tickUpper: params.tickUpper,
                        amount0Desired: balanceOf(params.token0),
                        amount1Desired: balanceOf(params.token1),
                        amount0Min: params.amount0Min,
                        amount1Min: params.amount1Min,
                        recipient: params.recipient,
                        deadline: type(uint256).max // deadline should be checked via multicall
                    })
                )
            );
    }

    /// @inheritdoc IApproveAndCall
    function increaseLiquidity(IncreaseLiquidityParams calldata params)
        external
        payable
        override
        returns (bytes memory result)
    {
        return
            callPositionManager(
                abi.encodeWithSelector(
                    INonfungiblePositionManager.increaseLiquidity.selector,
                    INonfungiblePositionManager.IncreaseLiquidityParams({
                        tokenId: params.tokenId,
                        amount0Desired: balanceOf(params.token0),
                        amount1Desired: balanceOf(params.token1),
                        amount0Min: params.amount0Min,
                        amount1Min: params.amount1Min,
                        deadline: type(uint256).max // deadline should be checked via multicall
                    })
                )
            );
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '../interfaces/IMulticall.sol';

/// @title Multicall
/// @notice Enables calling multiple methods in a single call to the contract
abstract contract Multicall is IMulticall {
    /// @inheritdoc IMulticall
    function multicall(bytes[] calldata data) public payable override returns (bytes[] memory results) {
        results = new bytes[](data.length);
        for (uint256 i = 0; i < data.length; i++) {
            (bool success, bytes memory result) = address(this).delegatecall(data[i]);

            if (!success) {
                // Next 5 lines from https://ethereum.stackexchange.com/a/83577
                if (result.length < 68) revert();
                assembly {
                    result := add(result, 0x04)
                }
                revert(abi.decode(result, (string)));
            }

            results[i] = result;
        }
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;

/// @title Function for getting block timestamp
/// @dev Base contract that is overridden for tests
abstract contract BlockTimestamp {
    /// @dev Method that exists purely to be overridden for tests
    /// @return The current block timestamp
    function _blockTimestamp() internal view virtual returns (uint256) {
        return block.timestamp;
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
pragma abicoder v2;

import '@elkdex/v3-core/contracts/interfaces/IElkDexV3Pool.sol';

import '../interfaces/ITickLens.sol';

/// @title Tick Lens contract
contract TickLens is ITickLens {
    /// @inheritdoc ITickLens
    function getPopulatedTicksInWord(address pool, int16 tickBitmapIndex)
        public
        view
        override
        returns (PopulatedTick[] memory populatedTicks)
    {
        // fetch bitmap
        uint256 bitmap = IElkDexV3Pool(pool).tickBitmap(tickBitmapIndex);

        // calculate the number of populated ticks
        uint256 numberOfPopulatedTicks;
        for (uint256 i = 0; i < 256; i++) {
            if (bitmap & (1 << i) > 0) numberOfPopulatedTicks++;
        }

        // fetch populated tick data
        int24 tickSpacing = IElkDexV3Pool(pool).tickSpacing();
        populatedTicks = new PopulatedTick[](numberOfPopulatedTicks);
        for (uint256 i = 0; i < 256; i++) {
            if (bitmap & (1 << i) > 0) {
                int24 populatedTick = ((int24(tickBitmapIndex) << 8) + int24(i)) * tickSpacing;
                (uint128 liquidityGross, int128 liquidityNet, , , , , , ) = IElkDexV3Pool(pool).ticks(populatedTick);
                populatedTicks[--numberOfPopulatedTicks] = PopulatedTick({
                    tick: populatedTick,
                    liquidityNet: liquidityNet,
                    liquidityGross: liquidityGross
                });
            }
        }
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Callback for IElkDexV3PoolActions#swap
/// @notice Any contract that calls IElkDexV3PoolActions#swap must implement this interface
interface IElkDexV3SwapCallback {
    /// @notice Called to `msg.sender` after executing a swap via IElkDexV3Pool#swap.
    /// @dev In the implementation you must pay the pool tokens owed for the swap.
    /// The caller of this method must be checked to be a ElkDexV3Pool deployed by the canonical ElkDexV3Factory.
    /// amount0Delta and amount1Delta can both be 0 if no tokens were swapped.
    /// @param amount0Delta The amount of token0 that was sent (negative) or must be received (positive) by the pool by
    /// the end of the swap. If positive, the callback must send that amount of token0 to the pool.
    /// @param amount1Delta The amount of token1 that was sent (negative) or must be received (positive) by the pool by
    /// the end of the swap. If positive, the callback must send that amount of token1 to the pool.
    /// @param data Any data passed through by the caller via the IElkDexV3PoolActions#swap call
    function elkDexV3SwapCallback(
        int256 amount0Delta,
        int256 amount1Delta,
        bytes calldata data
    ) external;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '@elkdex/v3-periphery/contracts/base/Multicall.sol';

import '../interfaces/IMulticallExtended.sol';
import '../base/PeripheryValidationExtended.sol';

/// @title Multicall
/// @notice Enables calling multiple methods in a single call to the contract
abstract contract MulticallExtended is IMulticallExtended, Multicall, PeripheryValidationExtended {
    /// @inheritdoc IMulticallExtended
    function multicall(uint256 deadline, bytes[] calldata data)
        external
        payable
        override
        checkDeadline(deadline)
        returns (bytes[] memory)
    {
        return multicall(data);
    }

    /// @inheritdoc IMulticallExtended
    function multicall(bytes32 previousBlockhash, bytes[] calldata data)
        external
        payable
        override
        checkPreviousBlockhash(previousBlockhash)
        returns (bytes[] memory)
    {
        return multicall(data);
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

import '@openzeppelin/contracts/token/ERC721/IERC721Metadata.sol';
import '@openzeppelin/contracts/token/ERC721/IERC721Enumerable.sol';

import './IPoolInitializer.sol';
import './IERC721Permit.sol';
import './IPeripheryPayments.sol';
import './IPeripheryImmutableState.sol';
import '../libraries/PoolAddress.sol';

/// @title Non-fungible token for positions
/// @notice Wraps ElkDex V3 positions in a non-fungible token interface which allows for them to be transferred
/// and authorized.
interface INonfungiblePositionManager is
    IPoolInitializer,
    IPeripheryPayments,
    IPeripheryImmutableState,
    IERC721Metadata,
    IERC721Enumerable,
    IERC721Permit
{
    /// @notice Emitted when liquidity is increased for a position NFT
    /// @dev Also emitted when a token is minted
    /// @param tokenId The ID of the token for which liquidity was increased
    /// @param liquidity The amount by which liquidity for the NFT position was increased
    /// @param amount0 The amount of token0 that was paid for the increase in liquidity
    /// @param amount1 The amount of token1 that was paid for the increase in liquidity
    event IncreaseLiquidity(uint256 indexed tokenId, uint128 liquidity, uint256 amount0, uint256 amount1);
    /// @notice Emitted when liquidity is decreased for a position NFT
    /// @param tokenId The ID of the token for which liquidity was decreased
    /// @param liquidity The amount by which liquidity for the NFT position was decreased
    /// @param amount0 The amount of token0 that was accounted for the decrease in liquidity
    /// @param amount1 The amount of token1 that was accounted for the decrease in liquidity
    event DecreaseLiquidity(uint256 indexed tokenId, uint128 liquidity, uint256 amount0, uint256 amount1);
    /// @notice Emitted when tokens are collected for a position NFT
    /// @dev The amounts reported may not be exactly equivalent to the amounts transferred, due to rounding behavior
    /// @param tokenId The ID of the token for which underlying tokens were collected
    /// @param recipient The address of the account that received the collected tokens
    /// @param amount0 The amount of token0 owed to the position that was collected
    /// @param amount1 The amount of token1 owed to the position that was collected
    event Collect(uint256 indexed tokenId, address recipient, uint256 amount0, uint256 amount1);

    /// @notice Returns the position information associated with a given token ID.
    /// @dev Throws if the token ID is not valid.
    /// @param tokenId The ID of the token that represents the position
    /// @return nonce The nonce for permits
    /// @return operator The address that is approved for spending
    /// @return token0 The address of the token0 for a specific pool
    /// @return token1 The address of the token1 for a specific pool
    /// @return fee The fee associated with the pool
    /// @return tickLower The lower end of the tick range for the position
    /// @return tickUpper The higher end of the tick range for the position
    /// @return liquidity The liquidity of the position
    /// @return feeGrowthInside0LastX128 The fee growth of token0 as of the last action on the individual position
    /// @return feeGrowthInside1LastX128 The fee growth of token1 as of the last action on the individual position
    /// @return tokensOwed0 The uncollected amount of token0 owed to the position as of the last computation
    /// @return tokensOwed1 The uncollected amount of token1 owed to the position as of the last computation
    function positions(uint256 tokenId)
        external
        view
        returns (
            uint96 nonce,
            address operator,
            address token0,
            address token1,
            uint24 fee,
            int24 tickLower,
            int24 tickUpper,
            uint128 liquidity,
            uint256 feeGrowthInside0LastX128,
            uint256 feeGrowthInside1LastX128,
            uint128 tokensOwed0,
            uint128 tokensOwed1
        );

    struct MintParams {
        address token0;
        address token1;
        uint24 fee;
        int24 tickLower;
        int24 tickUpper;
        uint256 amount0Desired;
        uint256 amount1Desired;
        uint256 amount0Min;
        uint256 amount1Min;
        address recipient;
        uint256 deadline;
    }

    /// @notice Creates a new position wrapped in a NFT
    /// @dev Call this when the pool does exist and is initialized. Note that if the pool is created but not initialized
    /// a method does not exist, i.e. the pool is assumed to be initialized.
    /// @param params The params necessary to mint a position, encoded as `MintParams` in calldata
    /// @return tokenId The ID of the token that represents the minted position
    /// @return liquidity The amount of liquidity for this position
    /// @return amount0 The amount of token0
    /// @return amount1 The amount of token1
    function mint(MintParams calldata params)
        external
        payable
        returns (
            uint256 tokenId,
            uint128 liquidity,
            uint256 amount0,
            uint256 amount1
        );

    struct IncreaseLiquidityParams {
        uint256 tokenId;
        uint256 amount0Desired;
        uint256 amount1Desired;
        uint256 amount0Min;
        uint256 amount1Min;
        uint256 deadline;
    }

    /// @notice Increases the amount of liquidity in a position, with tokens paid by the `msg.sender`
    /// @param params tokenId The ID of the token for which liquidity is being increased,
    /// amount0Desired The desired amount of token0 to be spent,
    /// amount1Desired The desired amount of token1 to be spent,
    /// amount0Min The minimum amount of token0 to spend, which serves as a slippage check,
    /// amount1Min The minimum amount of token1 to spend, which serves as a slippage check,
    /// deadline The time by which the transaction must be included to effect the change
    /// @return liquidity The new liquidity amount as a result of the increase
    /// @return amount0 The amount of token0 to acheive resulting liquidity
    /// @return amount1 The amount of token1 to acheive resulting liquidity
    function increaseLiquidity(IncreaseLiquidityParams calldata params)
        external
        payable
        returns (
            uint128 liquidity,
            uint256 amount0,
            uint256 amount1
        );

    struct DecreaseLiquidityParams {
        uint256 tokenId;
        uint128 liquidity;
        uint256 amount0Min;
        uint256 amount1Min;
        uint256 deadline;
    }

    /// @notice Decreases the amount of liquidity in a position and accounts it to the position
    /// @param params tokenId The ID of the token for which liquidity is being decreased,
    /// amount The amount by which liquidity will be decreased,
    /// amount0Min The minimum amount of token0 that should be accounted for the burned liquidity,
    /// amount1Min The minimum amount of token1 that should be accounted for the burned liquidity,
    /// deadline The time by which the transaction must be included to effect the change
    /// @return amount0 The amount of token0 accounted to the position's tokens owed
    /// @return amount1 The amount of token1 accounted to the position's tokens owed
    function decreaseLiquidity(DecreaseLiquidityParams calldata params)
        external
        payable
        returns (uint256 amount0, uint256 amount1);

    struct CollectParams {
        uint256 tokenId;
        address recipient;
        uint128 amount0Max;
        uint128 amount1Max;
    }

    /// @notice Collects up to a maximum amount of fees owed to a specific position to the recipient
    /// @param params tokenId The ID of the NFT for which tokens are being collected,
    /// recipient The account that should receive the tokens,
    /// amount0Max The maximum amount of token0 to collect,
    /// amount1Max The maximum amount of token1 to collect
    /// @return amount0 The amount of fees collected in token0
    /// @return amount1 The amount of fees collected in token1
    function collect(CollectParams calldata params) external payable returns (uint256 amount0, uint256 amount1);

    /// @notice Burns a token ID, which deletes it from the NFT contract. The token must have 0 liquidity and all tokens
    /// must be collected first.
    /// @param tokenId The ID of the token that is being burned
    function burn(uint256 tokenId) external payable;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;

/// @title Periphery Payments
/// @notice Functions to ease deposits and withdrawals of ETH
interface IPeripheryPayments {
    /// @notice Unwraps the contract's WETH9 balance and sends it to recipient as ETH.
    /// @dev The amountMinimum parameter prevents malicious contracts from stealing WETH9 from users.
    /// @param amountMinimum The minimum amount of WETH9 to unwrap
    /// @param recipient The address receiving ETH
    function unwrapWETH9(uint256 amountMinimum, address recipient) external payable;

    /// @notice Refunds any ETH balance held by this contract to the `msg.sender`
    /// @dev Useful for bundling with mint or increase liquidity that uses ether, or exact output swaps
    /// that use ether for the input amount
    function refundETH() external payable;

    /// @notice Transfers the full amount of a token held by this contract to recipient
    /// @dev The amountMinimum parameter prevents malicious contracts from stealing the token from users
    /// @param token The contract address of the token which will be transferred to `recipient`
    /// @param amountMinimum The minimum amount of token required for a transfer
    /// @param recipient The destination address of the token
    function sweepToken(
        address token,
        uint256 amountMinimum,
        address recipient
    ) external payable;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

/// @title Creates and initializes V3 Pools
/// @notice Provides a method for creating and initializing a pool, if necessary, for bundling with other methods that
/// require the pool to exist.
interface IPoolInitializer {
    /// @notice Creates a new pool if it does not exist, then initializes if not initialized
    /// @dev This method can be bundled with others via IMulticall for the first action (e.g. mint) performed against a pool
    /// @param token0 The contract address of token0 of the pool
    /// @param token1 The contract address of token1 of the pool
    /// @param fee The fee amount of the v3 pool for the specified token pair
    /// @param sqrtPriceX96 The initial square root price of the pool as a Q64.96 value
    /// @return pool Returns the pool address based on the pair of tokens and fee, will return the newly created pool address if necessary
    function createAndInitializePoolIfNecessary(
        address token0,
        address token1,
        uint24 fee,
        uint160 sqrtPriceX96
    ) external payable returns (address pool);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Pool state that can change
/// @notice These methods compose the pool's state, and can change with any frequency including multiple times
/// per transaction
interface IElkDexV3PoolState {
    /// @notice The 0th storage slot in the pool stores many values, and is exposed as a single method to save gas
    /// when accessed externally.
    /// @return sqrtPriceX96 The current price of the pool as a sqrt(token1/token0) Q64.96 value
    /// tick The current tick of the pool, i.e. according to the last tick transition that was run.
    /// This value may not always be equal to SqrtTickMath.getTickAtSqrtRatio(sqrtPriceX96) if the price is on a tick
    /// boundary.
    /// observationIndex The index of the last oracle observation that was written,
    /// observationCardinality The current maximum number of observations stored in the pool,
    /// observationCardinalityNext The next maximum number of observations, to be updated when the observation.
    /// feeProtocol The protocol fee for both tokens of the pool.
    /// Encoded as two 4 bit values, where the protocol fee of token1 is shifted 4 bits and the protocol fee of token0
    /// is the lower 4 bits. Used as the denominator of a fraction of the swap fee, e.g. 4 means 1/4th of the swap fee.
    /// unlocked Whether the pool is currently locked to reentrancy
    function slot0()
        external
        view
        returns (
            uint160 sqrtPriceX96,
            int24 tick,
            uint16 observationIndex,
            uint16 observationCardinality,
            uint16 observationCardinalityNext,
            uint8 feeProtocol,
            bool unlocked
        );

    /// @notice The fee growth as a Q128.128 fees of token0 collected per unit of liquidity for the entire life of the pool
    /// @dev This value can overflow the uint256
    function feeGrowthGlobal0X128() external view returns (uint256);

    /// @notice The fee growth as a Q128.128 fees of token1 collected per unit of liquidity for the entire life of the pool
    /// @dev This value can overflow the uint256
    function feeGrowthGlobal1X128() external view returns (uint256);

    /// @notice The amounts of token0 and token1 that are owed to the protocol
    /// @dev Protocol fees will never exceed uint128 max in either token
    function protocolFees() external view returns (uint128 token0, uint128 token1);

    /// @notice The currently in range liquidity available to the pool
    /// @dev This value has no relationship to the total liquidity across all ticks
    function liquidity() external view returns (uint128);

    /// @notice Look up information about a specific tick in the pool
    /// @param tick The tick to look up
    /// @return liquidityGross the total amount of position liquidity that uses the pool either as tick lower or
    /// tick upper,
    /// liquidityNet how much liquidity changes when the pool price crosses the tick,
    /// feeGrowthOutside0X128 the fee growth on the other side of the tick from the current tick in token0,
    /// feeGrowthOutside1X128 the fee growth on the other side of the tick from the current tick in token1,
    /// tickCumulativeOutside the cumulative tick value on the other side of the tick from the current tick
    /// secondsPerLiquidityOutsideX128 the seconds spent per liquidity on the other side of the tick from the current tick,
    /// secondsOutside the seconds spent on the other side of the tick from the current tick,
    /// initialized Set to true if the tick is initialized, i.e. liquidityGross is greater than 0, otherwise equal to false.
    /// Outside values can only be used if the tick is initialized, i.e. if liquidityGross is greater than 0.
    /// In addition, these values are only relative and must be used only in comparison to previous snapshots for
    /// a specific position.
    function ticks(int24 tick)
        external
        view
        returns (
            uint128 liquidityGross,
            int128 liquidityNet,
            uint256 feeGrowthOutside0X128,
            uint256 feeGrowthOutside1X128,
            int56 tickCumulativeOutside,
            uint160 secondsPerLiquidityOutsideX128,
            uint32 secondsOutside,
            bool initialized
        );

    /// @notice Returns 256 packed tick initialized boolean values. See TickBitmap for more information
    function tickBitmap(int16 wordPosition) external view returns (uint256);

    /// @notice Returns the information about a position by the position's key
    /// @param key The position's key is a hash of a preimage composed by the owner, tickLower and tickUpper
    /// @return _liquidity The amount of liquidity in the position,
    /// Returns feeGrowthInside0LastX128 fee growth of token0 inside the tick range as of the last mint/burn/poke,
    /// Returns feeGrowthInside1LastX128 fee growth of token1 inside the tick range as of the last mint/burn/poke,
    /// Returns tokensOwed0 the computed amount of token0 owed to the position as of the last mint/burn/poke,
    /// Returns tokensOwed1 the computed amount of token1 owed to the position as of the last mint/burn/poke
    function positions(bytes32 key)
        external
        view
        returns (
            uint128 _liquidity,
            uint256 feeGrowthInside0LastX128,
            uint256 feeGrowthInside1LastX128,
            uint128 tokensOwed0,
            uint128 tokensOwed1
        );

    /// @notice Returns data about a specific observation index
    /// @param index The element of the observations array to fetch
    /// @dev You most likely want to use #observe() instead of this method to get an observation as of some amount of time
    /// ago, rather than at a specific index in the array.
    /// @return blockTimestamp The timestamp of the observation,
    /// Returns tickCumulative the tick multiplied by seconds elapsed for the life of the pool as of the observation timestamp,
    /// Returns secondsPerLiquidityCumulativeX128 the seconds per in range liquidity for the life of the pool as of the observation timestamp,
    /// Returns initialized whether the observation has been initialized and the values are safe to use
    function observations(uint256 index)
        external
        view
        returns (
            uint32 blockTimestamp,
            int56 tickCumulative,
            uint160 secondsPerLiquidityCumulativeX128,
            bool initialized
        );
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;

import '@elkdex/v3-periphery/contracts/base/PeripheryValidation.sol';

abstract contract PeripheryValidationExtended is PeripheryValidation {
    modifier checkPreviousBlockhash(bytes32 previousBlockhash) {
        require(blockhash(block.number - 1) == previousBlockhash, 'Blockhash');
        _;
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '@elkdex/v3-core/contracts/libraries/SafeCast.sol';
import '@elkdex/v3-core/contracts/libraries/TickMath.sol';
import '@elkdex/v3-core/contracts/interfaces/IElkDexV3Pool.sol';
import '@elkdex/v3-periphery/contracts/libraries/Path.sol';
import '@elkdex/v3-periphery/contracts/libraries/PoolAddress.sol';
import '@elkdex/v3-periphery/contracts/libraries/CallbackValidation.sol';
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';

import './interfaces/IV3SwapRouter.sol';
import './base/PeripheryPaymentsWithFeeExtended.sol';
import './base/OracleSlippage.sol';
import './libraries/Constants.sol';

/// @title ElkDex V3 Swap Router
/// @notice Router for stateless execution of swaps against ElkDex V3
abstract contract V3SwapRouter is IV3SwapRouter, PeripheryPaymentsWithFeeExtended, OracleSlippage {
    using Path for bytes;
    using SafeCast for uint256;

    /// @dev Used as the placeholder value for amountInCached, because the computed amount in for an exact output swap
    /// can never actually be this value
    uint256 private constant DEFAULT_AMOUNT_IN_CACHED = type(uint256).max;

    /// @dev Transient storage variable used for returning the computed amount in for an exact output swap.
    uint256 private amountInCached = DEFAULT_AMOUNT_IN_CACHED;

    /// @dev Returns the pool for the given token pair and fee. The pool contract may or may not exist.
    function getPool(
        address tokenA,
        address tokenB,
        uint24 fee
    ) private view returns (IElkDexV3Pool) {
        return IElkDexV3Pool(PoolAddress.computeAddress(factory, PoolAddress.getPoolKey(tokenA, tokenB, fee)));
    }

    struct SwapCallbackData {
        bytes path;
        address payer;
    }

    /// @inheritdoc IElkDexV3SwapCallback
    function elkDexV3SwapCallback(
        int256 amount0Delta,
        int256 amount1Delta,
        bytes calldata _data
    ) external override {
        require(amount0Delta > 0 || amount1Delta > 0); // swaps entirely within 0-liquidity regions are not supported
        SwapCallbackData memory data = abi.decode(_data, (SwapCallbackData));
        (address tokenIn, address tokenOut, uint24 fee) = data.path.decodeFirstPool();
        CallbackValidation.verifyCallback(factory, tokenIn, tokenOut, fee);

        (bool isExactInput, uint256 amountToPay) =
            amount0Delta > 0
                ? (tokenIn < tokenOut, uint256(amount0Delta))
                : (tokenOut < tokenIn, uint256(amount1Delta));

        if (isExactInput) {
            pay(tokenIn, data.payer, msg.sender, amountToPay);
        } else {
            // either initiate the next swap or pay
            if (data.path.hasMultiplePools()) {
                data.path = data.path.skipToken();
                exactOutputInternal(amountToPay, msg.sender, 0, data);
            } else {
                amountInCached = amountToPay;
                // note that because exact output swaps are executed in reverse order, tokenOut is actually tokenIn
                pay(tokenOut, data.payer, msg.sender, amountToPay);
            }
        }
    }

    /// @dev Performs a single exact input swap
    function exactInputInternal(
        uint256 amountIn,
        address recipient,
        uint160 sqrtPriceLimitX96,
        SwapCallbackData memory data
    ) private returns (uint256 amountOut) {
        // find and replace recipient addresses
        if (recipient == Constants.MSG_SENDER) recipient = msg.sender;
        else if (recipient == Constants.ADDRESS_THIS) recipient = address(this);

        (address tokenIn, address tokenOut, uint24 fee) = data.path.decodeFirstPool();

        bool zeroForOne = tokenIn < tokenOut;

        (int256 amount0, int256 amount1) =
            getPool(tokenIn, tokenOut, fee).swap(
                recipient,
                zeroForOne,
                amountIn.toInt256(),
                sqrtPriceLimitX96 == 0
                    ? (zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1)
                    : sqrtPriceLimitX96,
                abi.encode(data)
            );

        return uint256(-(zeroForOne ? amount1 : amount0));
    }

    /// @inheritdoc IV3SwapRouter
    function exactInputSingle(ExactInputSingleParams memory params)
        external
        payable
        override
        returns (uint256 amountOut)
    {
        // use amountIn == Constants.CONTRACT_BALANCE as a flag to swap the entire balance of the contract
        bool hasAlreadyPaid;
        if (params.amountIn == Constants.CONTRACT_BALANCE) {
            hasAlreadyPaid = true;
            params.amountIn = IERC20(params.tokenIn).balanceOf(address(this));
        }

        amountOut = exactInputInternal(
            params.amountIn,
            params.recipient,
            params.sqrtPriceLimitX96,
            SwapCallbackData({
                path: abi.encodePacked(params.tokenIn, params.fee, params.tokenOut),
                payer: hasAlreadyPaid ? address(this) : msg.sender
            })
        );
        require(amountOut >= params.amountOutMinimum, 'Too little received');
    }

    /// @inheritdoc IV3SwapRouter
    function exactInput(ExactInputParams memory params) external payable override returns (uint256 amountOut) {
        // use amountIn == Constants.CONTRACT_BALANCE as a flag to swap the entire balance of the contract
        bool hasAlreadyPaid;
        if (params.amountIn == Constants.CONTRACT_BALANCE) {
            hasAlreadyPaid = true;
            (address tokenIn, , ) = params.path.decodeFirstPool();
            params.amountIn = IERC20(tokenIn).balanceOf(address(this));
        }

        address payer = hasAlreadyPaid ? address(this) : msg.sender;

        while (true) {
            bool hasMultiplePools = params.path.hasMultiplePools();

            // the outputs of prior swaps become the inputs to subsequent ones
            params.amountIn = exactInputInternal(
                params.amountIn,
                hasMultiplePools ? address(this) : params.recipient, // for intermediate swaps, this contract custodies
                0,
                SwapCallbackData({
                    path: params.path.getFirstPool(), // only the first pool in the path is necessary
                    payer: payer
                })
            );

            // decide whether to continue or terminate
            if (hasMultiplePools) {
                payer = address(this);
                params.path = params.path.skipToken();
            } else {
                amountOut = params.amountIn;
                break;
            }
        }

        require(amountOut >= params.amountOutMinimum, 'Too little received');
    }

    /// @dev Performs a single exact output swap
    function exactOutputInternal(
        uint256 amountOut,
        address recipient,
        uint160 sqrtPriceLimitX96,
        SwapCallbackData memory data
    ) private returns (uint256 amountIn) {
        // find and replace recipient addresses
        if (recipient == Constants.MSG_SENDER) recipient = msg.sender;
        else if (recipient == Constants.ADDRESS_THIS) recipient = address(this);

        (address tokenOut, address tokenIn, uint24 fee) = data.path.decodeFirstPool();

        bool zeroForOne = tokenIn < tokenOut;

        (int256 amount0Delta, int256 amount1Delta) =
            getPool(tokenIn, tokenOut, fee).swap(
                recipient,
                zeroForOne,
                -amountOut.toInt256(),
                sqrtPriceLimitX96 == 0
                    ? (zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1)
                    : sqrtPriceLimitX96,
                abi.encode(data)
            );

        uint256 amountOutReceived;
        (amountIn, amountOutReceived) = zeroForOne
            ? (uint256(amount0Delta), uint256(-amount1Delta))
            : (uint256(amount1Delta), uint256(-amount0Delta));
        // it's technically possible to not receive the full output amount,
        // so if no price limit has been specified, require this possibility away
        if (sqrtPriceLimitX96 == 0) require(amountOutReceived == amountOut);
    }

    /// @inheritdoc IV3SwapRouter
    function exactOutputSingle(ExactOutputSingleParams calldata params)
        external
        payable
        override
        returns (uint256 amountIn)
    {
        // avoid an SLOAD by using the swap return data
        amountIn = exactOutputInternal(
            params.amountOut,
            params.recipient,
            params.sqrtPriceLimitX96,
            SwapCallbackData({path: abi.encodePacked(params.tokenOut, params.fee, params.tokenIn), payer: msg.sender})
        );

        require(amountIn <= params.amountInMaximum, 'Too much requested');
        // has to be reset even though we don't use it in the single hop case
        amountInCached = DEFAULT_AMOUNT_IN_CACHED;
    }

    /// @inheritdoc IV3SwapRouter
    function exactOutput(ExactOutputParams calldata params) external payable override returns (uint256 amountIn) {
        exactOutputInternal(
            params.amountOut,
            params.recipient,
            0,
            SwapCallbackData({path: params.path, payer: msg.sender})
        );

        amountIn = amountInCached;
        require(amountIn <= params.amountInMaximum, 'Too much requested');
        amountInCached = DEFAULT_AMOUNT_IN_CACHED;
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title BitMath
/// @dev This library provides functionality for computing bit properties of an unsigned integer
library BitMath {
    /// @notice Returns the index of the most significant bit of the number,
    ///     where the least significant bit is at index 0 and the most significant bit is at index 255
    /// @dev The function satisfies the property:
    ///     x >= 2**mostSignificantBit(x) and x < 2**(mostSignificantBit(x)+1)
    /// @param x the value for which to compute the most significant bit, must be greater than 0
    /// @return r the index of the most significant bit
    function mostSignificantBit(uint256 x) internal pure returns (uint8 r) {
        require(x > 0);

        if (x >= 0x100000000000000000000000000000000) {
            x >>= 128;
            r += 128;
        }
        if (x >= 0x10000000000000000) {
            x >>= 64;
            r += 64;
        }
        if (x >= 0x100000000) {
            x >>= 32;
            r += 32;
        }
        if (x >= 0x10000) {
            x >>= 16;
            r += 16;
        }
        if (x >= 0x100) {
            x >>= 8;
            r += 8;
        }
        if (x >= 0x10) {
            x >>= 4;
            r += 4;
        }
        if (x >= 0x4) {
            x >>= 2;
            r += 2;
        }
        if (x >= 0x2) r += 1;
    }

    /// @notice Returns the index of the least significant bit of the number,
    ///     where the least significant bit is at index 0 and the most significant bit is at index 255
    /// @dev The function satisfies the property:
    ///     (x & 2**leastSignificantBit(x)) != 0 and (x & (2**(leastSignificantBit(x)) - 1)) == 0)
    /// @param x the value for which to compute the least significant bit, must be greater than 0
    /// @return r the index of the least significant bit
    function leastSignificantBit(uint256 x) internal pure returns (uint8 r) {
        require(x > 0);

        r = 255;
        if (x & type(uint128).max > 0) {
            r -= 128;
        } else {
            x >>= 128;
        }
        if (x & type(uint64).max > 0) {
            r -= 64;
        } else {
            x >>= 64;
        }
        if (x & type(uint32).max > 0) {
            r -= 32;
        } else {
            x >>= 32;
        }
        if (x & type(uint16).max > 0) {
            r -= 16;
        } else {
            x >>= 16;
        }
        if (x & type(uint8).max > 0) {
            r -= 8;
        } else {
            x >>= 8;
        }
        if (x & 0xf > 0) {
            r -= 4;
        } else {
            x >>= 4;
        }
        if (x & 0x3 > 0) {
            r -= 2;
        } else {
            x >>= 2;
        }
        if (x & 0x1 > 0) r -= 1;
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;

import '@openzeppelin/contracts/token/ERC20/IERC20.sol';

/// @title Interface for WETH9
interface IWETH9 is IERC20 {
    /// @notice Deposit ether to get wrapped ether
    function deposit() external payable;

    /// @notice Withdraw wrapped ether to get ether
    function withdraw(uint256) external;
}
          

// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

import "./IERC721.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721Metadata is IERC721 {

    /**
     * @dev Returns the token collection name.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the token collection symbol.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
     */
    function tokenURI(uint256 tokenId) external view returns (string memory);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;

import '@elkdex/v3-periphery/contracts/base/PeripheryPayments.sol';
import '@elkdex/v3-periphery/contracts/libraries/TransferHelper.sol';

import '../interfaces/IPeripheryPaymentsExtended.sol';

abstract contract PeripheryPaymentsExtended is IPeripheryPaymentsExtended, PeripheryPayments {
    /// @inheritdoc IPeripheryPaymentsExtended
    function unwrapWETH9(uint256 amountMinimum) external payable override {
        unwrapWETH9(amountMinimum, msg.sender);
    }

    /// @inheritdoc IPeripheryPaymentsExtended
    function wrapETH(uint256 value) external payable override {
        IWETH9(WETH9).deposit{value: value}();
    }

    /// @inheritdoc IPeripheryPaymentsExtended
    function sweepToken(address token, uint256 amountMinimum) external payable override {
        sweepToken(token, amountMinimum, msg.sender);
    }

    /// @inheritdoc IPeripheryPaymentsExtended
    function pull(address token, uint256 value) external payable override {
        TransferHelper.safeTransferFrom(token, msg.sender, address(this), value);
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Immutable state
/// @notice Functions that return immutable state of the router
interface IImmutableState {
    /// @return Returns the address of the ElkDex V2 factory
    function factoryV2() external view returns (address);

    /// @return Returns the address of ElkDex V3 NFT position manager
    function positionManager() external view returns (address);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;

/// @title Self Permit
/// @notice Functionality to call permit on any EIP-2612-compliant token for use in the route
interface ISelfPermit {
    /// @notice Permits this contract to spend a given token from `msg.sender`
    /// @dev The `owner` is always msg.sender and the `spender` is always address(this).
    /// @param token The address of the token spent
    /// @param value The amount that can be spent of token
    /// @param deadline A timestamp, the current blocktime must be less than or equal to this timestamp
    /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
    /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
    /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
    function selfPermit(
        address token,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external payable;

    /// @notice Permits this contract to spend a given token from `msg.sender`
    /// @dev The `owner` is always msg.sender and the `spender` is always address(this).
    /// Can be used instead of #selfPermit to prevent calls from failing due to a frontrun of a call to #selfPermit
    /// @param token The address of the token spent
    /// @param value The amount that can be spent of token
    /// @param deadline A timestamp, the current blocktime must be less than or equal to this timestamp
    /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
    /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
    /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
    function selfPermitIfNecessary(
        address token,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external payable;

    /// @notice Permits this contract to spend the sender's tokens for permit signatures that have the `allowed` parameter
    /// @dev The `owner` is always msg.sender and the `spender` is always address(this)
    /// @param token The address of the token spent
    /// @param nonce The current nonce of the owner
    /// @param expiry The timestamp at which the permit is no longer valid
    /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
    /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
    /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
    function selfPermitAllowed(
        address token,
        uint256 nonce,
        uint256 expiry,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external payable;

    /// @notice Permits this contract to spend the sender's tokens for permit signatures that have the `allowed` parameter
    /// @dev The `owner` is always msg.sender and the `spender` is always address(this)
    /// Can be used instead of #selfPermitAllowed to prevent calls from failing due to a frontrun of a call to #selfPermitAllowed.
    /// @param token The address of the token spent
    /// @param nonce The current nonce of the owner
    /// @param expiry The timestamp at which the permit is no longer valid
    /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
    /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
    /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
    function selfPermitAllowedIfNecessary(
        address token,
        uint256 nonce,
        uint256 expiry,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external payable;
}
          

// SPDX-License-Identifier: UNLICENSED
pragma solidity =0.7.6;

import "@elkdex/v3-periphery/contracts/lens/ElkDexInterfaceMulticall.sol";
import "@elkdex/v3-periphery/contracts/lens/TickLens.sol";
import "@elkdex/v3-periphery/contracts/V3Migrator.sol";
import "@elkdex/v3-periphery/contracts/SwapRouter.sol";
import "@elkdex/v3-periphery/contracts/lens/Quoter.sol";
import "@elkdex/swap-router-contracts/contracts/lens/QuoterV2.sol";
import "@elkdex/swap-router-contracts/contracts/SwapRouter02.sol";
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Pool state that never changes
/// @notice These parameters are fixed for a pool forever, i.e., the methods will always return the same values
interface IElkDexV3PoolImmutables {
    /// @notice The contract that deployed the pool, which must adhere to the IElkDexV3Factory interface
    /// @return The contract address
    function factory() external view returns (address);

    /// @notice The first of the two tokens of the pool, sorted by address
    /// @return The token contract address
    function token0() external view returns (address);

    /// @notice The second of the two tokens of the pool, sorted by address
    /// @return The token contract address
    function token1() external view returns (address);

    /// @notice The pool's fee in hundredths of a bip, i.e. 1e-6
    /// @return The fee
    function fee() external view returns (uint24);

    /// @notice The pool tick spacing
    /// @dev Ticks can only be used at multiples of this value, minimum of 1 and always positive
    /// e.g.: a tickSpacing of 3 means ticks can be initialized every 3rd tick, i.e., ..., -6, -3, 0, 3, 6, ...
    /// This value is an int24 to avoid casting even though it is always positive.
    /// @return The tick spacing
    function tickSpacing() external view returns (int24);

    /// @notice The maximum amount of position liquidity that can use any tick in the range
    /// @dev This parameter is enforced per tick to prevent liquidity from overflowing a uint128 at any point, and
    /// also prevents out-of-range liquidity from being used to prevent adding in-range liquidity to a pool
    /// @return The max amount of liquidity per tick
    function maxLiquidityPerTick() external view returns (uint128);
}
          

// SPDX-License-Identifier: MIT
pragma solidity >=0.4.0 <0.8.0;

/// @title Contains 512-bit math functions
/// @notice Facilitates multiplication and division that can have overflow of an intermediate value without any loss of precision
/// @dev Handles "phantom overflow" i.e., allows multiplication and division where an intermediate value overflows 256 bits
library FullMath {
    /// @notice Calculates floor(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
    /// @param a The multiplicand
    /// @param b The multiplier
    /// @param denominator The divisor
    /// @return result The 256-bit result
    /// @dev Credit to Remco Bloemen under MIT license https://xn--2-umb.com/21/muldiv
    function mulDiv(
        uint256 a,
        uint256 b,
        uint256 denominator
    ) internal pure returns (uint256 result) {
        // 512-bit multiply [prod1 prod0] = a * b
        // Compute the product mod 2**256 and mod 2**256 - 1
        // then use the Chinese Remainder Theorem to reconstruct
        // the 512 bit result. The result is stored in two 256
        // variables such that product = prod1 * 2**256 + prod0
        uint256 prod0; // Least significant 256 bits of the product
        uint256 prod1; // Most significant 256 bits of the product
        assembly {
            let mm := mulmod(a, b, not(0))
            prod0 := mul(a, b)
            prod1 := sub(sub(mm, prod0), lt(mm, prod0))
        }

        // Handle non-overflow cases, 256 by 256 division
        if (prod1 == 0) {
            require(denominator > 0);
            assembly {
                result := div(prod0, denominator)
            }
            return result;
        }

        // Make sure the result is less than 2**256.
        // Also prevents denominator == 0
        require(denominator > prod1);

        ///////////////////////////////////////////////
        // 512 by 256 division.
        ///////////////////////////////////////////////

        // Make division exact by subtracting the remainder from [prod1 prod0]
        // Compute remainder using mulmod
        uint256 remainder;
        assembly {
            remainder := mulmod(a, b, denominator)
        }
        // Subtract 256 bit number from 512 bit number
        assembly {
            prod1 := sub(prod1, gt(remainder, prod0))
            prod0 := sub(prod0, remainder)
        }

        // Factor powers of two out of denominator
        // Compute largest power of two divisor of denominator.
        // Always >= 1.
        uint256 twos = -denominator & denominator;
        // Divide denominator by power of two
        assembly {
            denominator := div(denominator, twos)
        }

        // Divide [prod1 prod0] by the factors of two
        assembly {
            prod0 := div(prod0, twos)
        }
        // Shift in bits from prod1 into prod0. For this we need
        // to flip `twos` such that it is 2**256 / twos.
        // If twos is zero, then it becomes one
        assembly {
            twos := add(div(sub(0, twos), twos), 1)
        }
        prod0 |= prod1 * twos;

        // Invert denominator mod 2**256
        // Now that denominator is an odd number, it has an inverse
        // modulo 2**256 such that denominator * inv = 1 mod 2**256.
        // Compute the inverse by starting with a seed that is correct
        // correct for four bits. That is, denominator * inv = 1 mod 2**4
        uint256 inv = (3 * denominator) ^ 2;
        // Now use Newton-Raphson iteration to improve the precision.
        // Thanks to Hensel's lifting lemma, this also works in modular
        // arithmetic, doubling the correct bits in each step.
        inv *= 2 - denominator * inv; // inverse mod 2**8
        inv *= 2 - denominator * inv; // inverse mod 2**16
        inv *= 2 - denominator * inv; // inverse mod 2**32
        inv *= 2 - denominator * inv; // inverse mod 2**64
        inv *= 2 - denominator * inv; // inverse mod 2**128
        inv *= 2 - denominator * inv; // inverse mod 2**256

        // Because the division is now exact we can divide by multiplying
        // with the modular inverse of denominator. This will give us the
        // correct result modulo 2**256. Since the precoditions guarantee
        // that the outcome is less than 2**256, this is the final result.
        // We don't need to compute the high bits of the result and prod1
        // is no longer required.
        result = prod0 * inv;
        return result;
    }

    /// @notice Calculates ceil(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
    /// @param a The multiplicand
    /// @param b The multiplier
    /// @param denominator The divisor
    /// @return result The 256-bit result
    function mulDivRoundingUp(
        uint256 a,
        uint256 b,
        uint256 denominator
    ) internal pure returns (uint256 result) {
        result = mulDiv(a, b, denominator);
        if (mulmod(a, b, denominator) > 0) {
            require(result < type(uint256).max);
            result++;
        }
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

/// @title Router token swapping functionality
/// @notice Functions for swapping tokens via ElkDex V2
interface IV2SwapRouter {
    /// @notice Swaps `amountIn` of one token for as much as possible of another token
    /// @dev Setting `amountIn` to 0 will cause the contract to look up its own balance,
    /// and swap the entire amount, enabling contracts to send tokens before calling this function.
    /// @param amountIn The amount of token to swap
    /// @param amountOutMin The minimum amount of output that must be received
    /// @param path The ordered list of tokens to swap through
    /// @param to The recipient address
    /// @return amountOut The amount of the received token
    function swapExactTokensForTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to
    ) external payable returns (uint256 amountOut);

    /// @notice Swaps as little as possible of one token for an exact amount of another token
    /// @param amountOut The amount of token to swap for
    /// @param amountInMax The maximum amount of input that the caller will pay
    /// @param path The ordered list of tokens to swap through
    /// @param to The recipient address
    /// @return amountIn The amount of token to pay
    function swapTokensForExactTokens(
        uint256 amountOut,
        uint256 amountInMax,
        address[] calldata path,
        address to
    ) external payable returns (uint256 amountIn);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.0;

/// @title Optimized overflow and underflow safe math operations
/// @notice Contains methods for doing math operations that revert on overflow or underflow for minimal gas cost
library LowGasSafeMath {
    /// @notice Returns x + y, reverts if sum overflows uint256
    /// @param x The augend
    /// @param y The addend
    /// @return z The sum of x and y
    function add(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require((z = x + y) >= x);
    }

    /// @notice Returns x - y, reverts if underflows
    /// @param x The minuend
    /// @param y The subtrahend
    /// @return z The difference of x and y
    function sub(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require((z = x - y) <= x);
    }

    /// @notice Returns x * y, reverts if overflows
    /// @param x The multiplicand
    /// @param y The multiplier
    /// @return z The product of x and y
    function mul(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require(x == 0 || (z = x * y) / x == y);
    }

    /// @notice Returns x + y, reverts if overflows or underflows
    /// @param x The augend
    /// @param y The addend
    /// @return z The sum of x and y
    function add(int256 x, int256 y) internal pure returns (int256 z) {
        require((z = x + y) >= x == (y >= 0));
    }

    /// @notice Returns x - y, reverts if overflows or underflows
    /// @param x The minuend
    /// @param y The subtrahend
    /// @return z The difference of x and y
    function sub(int256 x, int256 y) internal pure returns (int256 z) {
        require((z = x - y) <= x == (y >= 0));
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0 <0.8.0;

import '@elkdex/v3-core/contracts/libraries/FullMath.sol';
import '@elkdex/v3-core/contracts/libraries/TickMath.sol';
import '@elkdex/v3-core/contracts/interfaces/IElkDexV3Pool.sol';

/// @title Oracle library
/// @notice Provides functions to integrate with V3 pool oracle
library OracleLibrary {
    /// @notice Calculates time-weighted means of tick and liquidity for a given ElkDex V3 pool
    /// @param pool Address of the pool that we want to observe
    /// @param secondsAgo Number of seconds in the past from which to calculate the time-weighted means
    /// @return arithmeticMeanTick The arithmetic mean tick from (block.timestamp - secondsAgo) to block.timestamp
    /// @return harmonicMeanLiquidity The harmonic mean liquidity from (block.timestamp - secondsAgo) to block.timestamp
    function consult(address pool, uint32 secondsAgo)
        internal
        view
        returns (int24 arithmeticMeanTick, uint128 harmonicMeanLiquidity)
    {
        require(secondsAgo != 0, 'BP');

        uint32[] memory secondsAgos = new uint32[](2);
        secondsAgos[0] = secondsAgo;
        secondsAgos[1] = 0;

        (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s) =
            IElkDexV3Pool(pool).observe(secondsAgos);

        int56 tickCumulativesDelta = tickCumulatives[1] - tickCumulatives[0];
        uint160 secondsPerLiquidityCumulativesDelta =
            secondsPerLiquidityCumulativeX128s[1] - secondsPerLiquidityCumulativeX128s[0];

        arithmeticMeanTick = int24(tickCumulativesDelta / secondsAgo);
        // Always round to negative infinity
        if (tickCumulativesDelta < 0 && (tickCumulativesDelta % secondsAgo != 0)) arithmeticMeanTick--;

        // We are multiplying here instead of shifting to ensure that harmonicMeanLiquidity doesn't overflow uint128
        uint192 secondsAgoX160 = uint192(secondsAgo) * type(uint160).max;
        harmonicMeanLiquidity = uint128(secondsAgoX160 / (uint192(secondsPerLiquidityCumulativesDelta) << 32));
    }

    /// @notice Given a tick and a token amount, calculates the amount of token received in exchange
    /// @param tick Tick value used to calculate the quote
    /// @param baseAmount Amount of token to be converted
    /// @param baseToken Address of an ERC20 token contract used as the baseAmount denomination
    /// @param quoteToken Address of an ERC20 token contract used as the quoteAmount denomination
    /// @return quoteAmount Amount of quoteToken received for baseAmount of baseToken
    function getQuoteAtTick(
        int24 tick,
        uint128 baseAmount,
        address baseToken,
        address quoteToken
    ) internal pure returns (uint256 quoteAmount) {
        uint160 sqrtRatioX96 = TickMath.getSqrtRatioAtTick(tick);

        // Calculate quoteAmount with better precision if it doesn't overflow when multiplied by itself
        if (sqrtRatioX96 <= type(uint128).max) {
            uint256 ratioX192 = uint256(sqrtRatioX96) * sqrtRatioX96;
            quoteAmount = baseToken < quoteToken
                ? FullMath.mulDiv(ratioX192, baseAmount, 1 << 192)
                : FullMath.mulDiv(1 << 192, baseAmount, ratioX192);
        } else {
            uint256 ratioX128 = FullMath.mulDiv(sqrtRatioX96, sqrtRatioX96, 1 << 64);
            quoteAmount = baseToken < quoteToken
                ? FullMath.mulDiv(ratioX128, baseAmount, 1 << 128)
                : FullMath.mulDiv(1 << 128, baseAmount, ratioX128);
        }
    }

    /// @notice Given a pool, it returns the number of seconds ago of the oldest stored observation
    /// @param pool Address of ElkDex V3 pool that we want to observe
    /// @return secondsAgo The number of seconds ago of the oldest observation stored for the pool
    function getOldestObservationSecondsAgo(address pool) internal view returns (uint32 secondsAgo) {
        (, , uint16 observationIndex, uint16 observationCardinality, , , ) = IElkDexV3Pool(pool).slot0();
        require(observationCardinality > 0, 'NI');

        (uint32 observationTimestamp, , , bool initialized) =
            IElkDexV3Pool(pool).observations((observationIndex + 1) % observationCardinality);

        // The next index might not be initialized if the cardinality is in the process of increasing
        // In this case the oldest observation is always in index 0
        if (!initialized) {
            (observationTimestamp, , , ) = IElkDexV3Pool(pool).observations(0);
        }

        secondsAgo = uint32(block.timestamp) - observationTimestamp;
    }

    /// @notice Given a pool, it returns the tick value as of the start of the current block
    /// @param pool Address of ElkDex V3 pool
    /// @return The tick that the pool was in at the start of the current block
    function getBlockStartingTickAndLiquidity(address pool) internal view returns (int24, uint128) {
        (, int24 tick, uint16 observationIndex, uint16 observationCardinality, , , ) = IElkDexV3Pool(pool).slot0();

        // 2 observations are needed to reliably calculate the block starting tick
        require(observationCardinality > 1, 'NEO');

        // If the latest observation occurred in the past, then no tick-changing trades have happened in this block
        // therefore the tick in `slot0` is the same as at the beginning of the current block.
        // We don't need to check if this observation is initialized - it is guaranteed to be.
        (uint32 observationTimestamp, int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128, ) =
            IElkDexV3Pool(pool).observations(observationIndex);
        if (observationTimestamp != uint32(block.timestamp)) {
            return (tick, IElkDexV3Pool(pool).liquidity());
        }

        uint256 prevIndex = (uint256(observationIndex) + observationCardinality - 1) % observationCardinality;
        (
            uint32 prevObservationTimestamp,
            int56 prevTickCumulative,
            uint160 prevSecondsPerLiquidityCumulativeX128,
            bool prevInitialized
        ) = IElkDexV3Pool(pool).observations(prevIndex);

        require(prevInitialized, 'ONI');

        uint32 delta = observationTimestamp - prevObservationTimestamp;
        tick = int24((tickCumulative - prevTickCumulative) / delta);
        uint128 liquidity =
            uint128(
                (uint192(delta) * type(uint160).max) /
                    (uint192(secondsPerLiquidityCumulativeX128 - prevSecondsPerLiquidityCumulativeX128) << 32)
            );
        return (tick, liquidity);
    }

    /// @notice Information for calculating a weighted arithmetic mean tick
    struct WeightedTickData {
        int24 tick;
        uint128 weight;
    }

    /// @notice Given an array of ticks and weights, calculates the weighted arithmetic mean tick
    /// @param weightedTickData An array of ticks and weights
    /// @return weightedArithmeticMeanTick The weighted arithmetic mean tick
    /// @dev Each entry of `weightedTickData` should represents ticks from pools with the same underlying pool tokens. If they do not,
    /// extreme care must be taken to ensure that ticks are comparable (including decimal differences).
    /// @dev Note that the weighted arithmetic mean tick corresponds to the weighted geometric mean price.
    function getWeightedArithmeticMeanTick(WeightedTickData[] memory weightedTickData)
        internal
        pure
        returns (int24 weightedArithmeticMeanTick)
    {
        // Accumulates the sum of products between each tick and its weight
        int256 numerator;

        // Accumulates the sum of the weights
        uint256 denominator;

        // Products fit in 152 bits, so it would take an array of length ~2**104 to overflow this logic
        for (uint256 i; i < weightedTickData.length; i++) {
            numerator += weightedTickData[i].tick * int256(weightedTickData[i].weight);
            denominator += weightedTickData[i].weight;
        }

        weightedArithmeticMeanTick = int24(numerator / int256(denominator));
        // Always round to negative infinity
        if (numerator < 0 && (numerator % int256(denominator) != 0)) weightedArithmeticMeanTick--;
    }

    /// @notice Returns the "synthetic" tick which represents the price of the first entry in `tokens` in terms of the last
    /// @dev Useful for calculating relative prices along routes.
    /// @dev There must be one tick for each pairwise set of tokens.
    /// @param tokens The token contract addresses
    /// @param ticks The ticks, representing the price of each token pair in `tokens`
    /// @return syntheticTick The synthetic tick, representing the relative price of the outermost tokens in `tokens`
    function getChainedPrice(address[] memory tokens, int24[] memory ticks)
        internal
        pure
        returns (int256 syntheticTick)
    {
        require(tokens.length - 1 == ticks.length, 'DL');
        for (uint256 i = 1; i <= ticks.length; i++) {
            // check the tokens for address sort order, then accumulate the
            // ticks into the running synthetic tick, ensuring that intermediate tokens "cancel out"
            tokens[i - 1] < tokens[i] ? syntheticTick += ticks[i - 1] : syntheticTick -= ticks[i - 1];
        }
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Permissionless pool actions
/// @notice Contains pool methods that can be called by anyone
interface IElkDexV3PoolActions {
    /// @notice Sets the initial price for the pool
    /// @dev Price is represented as a sqrt(amountToken1/amountToken0) Q64.96 value
    /// @param sqrtPriceX96 the initial sqrt price of the pool as a Q64.96
    function initialize(uint160 sqrtPriceX96) external;

    /// @notice Adds liquidity for the given recipient/tickLower/tickUpper position
    /// @dev The caller of this method receives a callback in the form of IElkDexV3MintCallback#elkDexV3MintCallback
    /// in which they must pay any token0 or token1 owed for the liquidity. The amount of token0/token1 due depends
    /// on tickLower, tickUpper, the amount of liquidity, and the current price.
    /// @param recipient The address for which the liquidity will be created
    /// @param tickLower The lower tick of the position in which to add liquidity
    /// @param tickUpper The upper tick of the position in which to add liquidity
    /// @param amount The amount of liquidity to mint
    /// @param data Any data that should be passed through to the callback
    /// @return amount0 The amount of token0 that was paid to mint the given amount of liquidity. Matches the value in the callback
    /// @return amount1 The amount of token1 that was paid to mint the given amount of liquidity. Matches the value in the callback
    function mint(
        address recipient,
        int24 tickLower,
        int24 tickUpper,
        uint128 amount,
        bytes calldata data
    ) external returns (uint256 amount0, uint256 amount1);

    /// @notice Collects tokens owed to a position
    /// @dev Does not recompute fees earned, which must be done either via mint or burn of any amount of liquidity.
    /// Collect must be called by the position owner. To withdraw only token0 or only token1, amount0Requested or
    /// amount1Requested may be set to zero. To withdraw all tokens owed, caller may pass any value greater than the
    /// actual tokens owed, e.g. type(uint128).max. Tokens owed may be from accumulated swap fees or burned liquidity.
    /// @param recipient The address which should receive the fees collected
    /// @param tickLower The lower tick of the position for which to collect fees
    /// @param tickUpper The upper tick of the position for which to collect fees
    /// @param amount0Requested How much token0 should be withdrawn from the fees owed
    /// @param amount1Requested How much token1 should be withdrawn from the fees owed
    /// @return amount0 The amount of fees collected in token0
    /// @return amount1 The amount of fees collected in token1
    function collect(
        address recipient,
        int24 tickLower,
        int24 tickUpper,
        uint128 amount0Requested,
        uint128 amount1Requested
    ) external returns (uint128 amount0, uint128 amount1);

    /// @notice Burn liquidity from the sender and account tokens owed for the liquidity to the position
    /// @dev Can be used to trigger a recalculation of fees owed to a position by calling with an amount of 0
    /// @dev Fees must be collected separately via a call to #collect
    /// @param tickLower The lower tick of the position for which to burn liquidity
    /// @param tickUpper The upper tick of the position for which to burn liquidity
    /// @param amount How much liquidity to burn
    /// @return amount0 The amount of token0 sent to the recipient
    /// @return amount1 The amount of token1 sent to the recipient
    function burn(
        int24 tickLower,
        int24 tickUpper,
        uint128 amount
    ) external returns (uint256 amount0, uint256 amount1);

    /// @notice Swap token0 for token1, or token1 for token0
    /// @dev The caller of this method receives a callback in the form of IElkDexV3SwapCallback#elkDexV3SwapCallback
    /// @param recipient The address to receive the output of the swap
    /// @param zeroForOne The direction of the swap, true for token0 to token1, false for token1 to token0
    /// @param amountSpecified The amount of the swap, which implicitly configures the swap as exact input (positive), or exact output (negative)
    /// @param sqrtPriceLimitX96 The Q64.96 sqrt price limit. If zero for one, the price cannot be less than this
    /// value after the swap. If one for zero, the price cannot be greater than this value after the swap
    /// @param data Any data to be passed through to the callback
    /// @return amount0 The delta of the balance of token0 of the pool, exact when negative, minimum when positive
    /// @return amount1 The delta of the balance of token1 of the pool, exact when negative, minimum when positive
    function swap(
        address recipient,
        bool zeroForOne,
        int256 amountSpecified,
        uint160 sqrtPriceLimitX96,
        bytes calldata data
    ) external returns (int256 amount0, int256 amount1);

    /// @notice Receive token0 and/or token1 and pay it back, plus a fee, in the callback
    /// @dev The caller of this method receives a callback in the form of IElkDexV3FlashCallback#elkDexV3FlashCallback
    /// @dev Can be used to donate underlying tokens pro-rata to currently in-range liquidity providers by calling
    /// with 0 amount{0,1} and sending the donation amount(s) from the callback
    /// @param recipient The address which will receive the token0 and token1 amounts
    /// @param amount0 The amount of token0 to send
    /// @param amount1 The amount of token1 to send
    /// @param data Any data to be passed through to the callback
    function flash(
        address recipient,
        uint256 amount0,
        uint256 amount1,
        bytes calldata data
    ) external;

    /// @notice Increase the maximum number of price and liquidity observations that this pool will store
    /// @dev This method is no-op if the pool already has an observationCardinalityNext greater than or equal to
    /// the input observationCardinalityNext.
    /// @param observationCardinalityNext The desired minimum number of observations for the pool to store
    function increaseObservationCardinalityNext(uint16 observationCardinalityNext) external;
}
          

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over `owner`'s tokens,
     * given `owner`'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @dev Returns the domain separator used in the encoding of the signature for `permit`, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

import '@elkdex/v3-core/contracts/interfaces/callback/IElkDexV3SwapCallback.sol';

/// @title Router token swapping functionality
/// @notice Functions for swapping tokens via ElkDex V3
interface IV3SwapRouter is IElkDexV3SwapCallback {
    struct ExactInputSingleParams {
        address tokenIn;
        address tokenOut;
        uint24 fee;
        address recipient;
        uint256 amountIn;
        uint256 amountOutMinimum;
        uint160 sqrtPriceLimitX96;
    }

    /// @notice Swaps `amountIn` of one token for as much as possible of another token
    /// @dev Setting `amountIn` to 0 will cause the contract to look up its own balance,
    /// and swap the entire amount, enabling contracts to send tokens before calling this function.
    /// @param params The parameters necessary for the swap, encoded as `ExactInputSingleParams` in calldata
    /// @return amountOut The amount of the received token
    function exactInputSingle(ExactInputSingleParams calldata params) external payable returns (uint256 amountOut);

    struct ExactInputParams {
        bytes path;
        address recipient;
        uint256 amountIn;
        uint256 amountOutMinimum;
    }

    /// @notice Swaps `amountIn` of one token for as much as possible of another along the specified path
    /// @dev Setting `amountIn` to 0 will cause the contract to look up its own balance,
    /// and swap the entire amount, enabling contracts to send tokens before calling this function.
    /// @param params The parameters necessary for the multi-hop swap, encoded as `ExactInputParams` in calldata
    /// @return amountOut The amount of the received token
    function exactInput(ExactInputParams calldata params) external payable returns (uint256 amountOut);

    struct ExactOutputSingleParams {
        address tokenIn;
        address tokenOut;
        uint24 fee;
        address recipient;
        uint256 amountOut;
        uint256 amountInMaximum;
        uint160 sqrtPriceLimitX96;
    }

    /// @notice Swaps as little as possible of one token for `amountOut` of another token
    /// that may remain in the router after the swap.
    /// @param params The parameters necessary for the swap, encoded as `ExactOutputSingleParams` in calldata
    /// @return amountIn The amount of the input token
    function exactOutputSingle(ExactOutputSingleParams calldata params) external payable returns (uint256 amountIn);

    struct ExactOutputParams {
        bytes path;
        address recipient;
        uint256 amountOut;
        uint256 amountInMaximum;
    }

    /// @notice Swaps as little as possible of one token for `amountOut` of another along the specified path (reversed)
    /// that may remain in the router after the swap.
    /// @param params The parameters necessary for the multi-hop swap, encoded as `ExactOutputParams` in calldata
    /// @return amountIn The amount of the input token
    function exactOutput(ExactOutputParams calldata params) external payable returns (uint256 amountIn);
}
          

pragma solidity >=0.5.0;

interface IElkDexV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);

    function mint(address to) external returns (uint liquidity);
    function burn(address to) external returns (uint amount0, uint amount1);
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;

    function initialize(address, address) external;
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;

/// @title QuoterV2 Interface
/// @notice Supports quoting the calculated amounts from exact input or exact output swaps.
/// @notice For each pool also tells you the number of initialized ticks crossed and the sqrt price of the pool after the swap.
/// @dev These functions are not marked view because they rely on calling non-view functions and reverting
/// to compute the result. They are also not gas efficient and should not be called on-chain.
interface IQuoterV2 {
    /// @notice Returns the amount out received for a given exact input swap without executing the swap
    /// @param path The path of the swap, i.e. each token pair and the pool fee
    /// @param amountIn The amount of the first token to swap
    /// @return amountOut The amount of the last token that would be received
    /// @return sqrtPriceX96AfterList List of the sqrt price after the swap for each pool in the path
    /// @return initializedTicksCrossedList List of the initialized ticks that the swap crossed for each pool in the path
    /// @return gasEstimate The estimate of the gas that the swap consumes
    function quoteExactInput(bytes memory path, uint256 amountIn)
        external
        returns (
            uint256 amountOut,
            uint160[] memory sqrtPriceX96AfterList,
            uint32[] memory initializedTicksCrossedList,
            uint256 gasEstimate
        );

    struct QuoteExactInputSingleParams {
        address tokenIn;
        address tokenOut;
        uint256 amountIn;
        uint24 fee;
        uint160 sqrtPriceLimitX96;
    }

    /// @notice Returns the amount out received for a given exact input but for a swap of a single pool
    /// @param params The params for the quote, encoded as `QuoteExactInputSingleParams`
    /// tokenIn The token being swapped in
    /// tokenOut The token being swapped out
    /// fee The fee of the token pool to consider for the pair
    /// amountIn The desired input amount
    /// sqrtPriceLimitX96 The price limit of the pool that cannot be exceeded by the swap
    /// @return amountOut The amount of `tokenOut` that would be received
    /// @return sqrtPriceX96After The sqrt price of the pool after the swap
    /// @return initializedTicksCrossed The number of initialized ticks that the swap crossed
    /// @return gasEstimate The estimate of the gas that the swap consumes
    function quoteExactInputSingle(QuoteExactInputSingleParams memory params)
        external
        returns (
            uint256 amountOut,
            uint160 sqrtPriceX96After,
            uint32 initializedTicksCrossed,
            uint256 gasEstimate
        );

    /// @notice Returns the amount in required for a given exact output swap without executing the swap
    /// @param path The path of the swap, i.e. each token pair and the pool fee. Path must be provided in reverse order
    /// @param amountOut The amount of the last token to receive
    /// @return amountIn The amount of first token required to be paid
    /// @return sqrtPriceX96AfterList List of the sqrt price after the swap for each pool in the path
    /// @return initializedTicksCrossedList List of the initialized ticks that the swap crossed for each pool in the path
    /// @return gasEstimate The estimate of the gas that the swap consumes
    function quoteExactOutput(bytes memory path, uint256 amountOut)
        external
        returns (
            uint256 amountIn,
            uint160[] memory sqrtPriceX96AfterList,
            uint32[] memory initializedTicksCrossedList,
            uint256 gasEstimate
        );

    struct QuoteExactOutputSingleParams {
        address tokenIn;
        address tokenOut;
        uint256 amount;
        uint24 fee;
        uint160 sqrtPriceLimitX96;
    }

    /// @notice Returns the amount in required to receive the given exact output amount but for a swap of a single pool
    /// @param params The params for the quote, encoded as `QuoteExactOutputSingleParams`
    /// tokenIn The token being swapped in
    /// tokenOut The token being swapped out
    /// fee The fee of the token pool to consider for the pair
    /// amountOut The desired output amount
    /// sqrtPriceLimitX96 The price limit of the pool that cannot be exceeded by the swap
    /// @return amountIn The amount required as the input for the swap in order to receive `amountOut`
    /// @return sqrtPriceX96After The sqrt price of the pool after the swap
    /// @return initializedTicksCrossed The number of initialized ticks that the swap crossed
    /// @return gasEstimate The estimate of the gas that the swap consumes
    function quoteExactOutputSingle(QuoteExactOutputSingleParams memory params)
        external
        returns (
            uint256 amountIn,
            uint160 sqrtPriceX96After,
            uint32 initializedTicksCrossed,
            uint256 gasEstimate
        );
}
          

// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.6.0;

import './BytesLib.sol';

/// @title Functions for manipulating path data for multihop swaps
library Path {
    using BytesLib for bytes;

    /// @dev The length of the bytes encoded address
    uint256 private constant ADDR_SIZE = 20;
    /// @dev The length of the bytes encoded fee
    uint256 private constant FEE_SIZE = 3;

    /// @dev The offset of a single token address and pool fee
    uint256 private constant NEXT_OFFSET = ADDR_SIZE + FEE_SIZE;
    /// @dev The offset of an encoded pool key
    uint256 private constant POP_OFFSET = NEXT_OFFSET + ADDR_SIZE;
    /// @dev The minimum length of an encoding that contains 2 or more pools
    uint256 private constant MULTIPLE_POOLS_MIN_LENGTH = POP_OFFSET + NEXT_OFFSET;

    /// @notice Returns true iff the path contains two or more pools
    /// @param path The encoded swap path
    /// @return True if path contains two or more pools, otherwise false
    function hasMultiplePools(bytes memory path) internal pure returns (bool) {
        return path.length >= MULTIPLE_POOLS_MIN_LENGTH;
    }

    /// @notice Returns the number of pools in the path
    /// @param path The encoded swap path
    /// @return The number of pools in the path
    function numPools(bytes memory path) internal pure returns (uint256) {
        // Ignore the first token address. From then on every fee and token offset indicates a pool.
        return ((path.length - ADDR_SIZE) / NEXT_OFFSET);
    }

    /// @notice Decodes the first pool in path
    /// @param path The bytes encoded swap path
    /// @return tokenA The first token of the given pool
    /// @return tokenB The second token of the given pool
    /// @return fee The fee level of the pool
    function decodeFirstPool(bytes memory path)
        internal
        pure
        returns (
            address tokenA,
            address tokenB,
            uint24 fee
        )
    {
        tokenA = path.toAddress(0);
        fee = path.toUint24(ADDR_SIZE);
        tokenB = path.toAddress(NEXT_OFFSET);
    }

    /// @notice Gets the segment corresponding to the first pool in the path
    /// @param path The bytes encoded swap path
    /// @return The segment containing all data necessary to target the first pool in the path
    function getFirstPool(bytes memory path) internal pure returns (bytes memory) {
        return path.slice(0, POP_OFFSET);
    }

    /// @notice Skips a token + fee element from the buffer and returns the remainder
    /// @param path The swap path
    /// @return The remaining token + fee elements in the path
    function skipToken(bytes memory path) internal pure returns (bytes memory) {
        return path.slice(NEXT_OFFSET, path.length - NEXT_OFFSET);
    }
}
          

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;

/// @title Permissioned pool actions
/// @notice Contains pool methods that may only be called by the factory owner
interface IElkDexV3PoolOwnerActions {
    /// @notice Set the denominator of the protocol's % share of the fees
    /// @param feeProtocol0 new protocol fee for token0 of the pool
    /// @param feeProtocol1 new protocol fee for token1 of the pool
    function setFeeProtocol(uint8 feeProtocol0, uint8 feeProtocol1) external;

    /// @notice Collect the protocol fee accrued to the pool
    /// @param recipient The address to which collected protocol fees should be sent
    /// @param amount0Requested The maximum amount of token0 to send, can be 0 to collect fees in only token1
    /// @param amount1Requested The maximum amount of token1 to send, can be 0 to collect fees in only token0
    /// @return amount0 The protocol fee collected in token0
    /// @return amount1 The protocol fee collected in token1
    function collectProtocol(
        address recipient,
        uint128 amount0Requested,
        uint128 amount1Requested
    ) external returns (uint128 amount0, uint128 amount1);
}