Algebra Positions NFT-V1

// SPDX-License-Identifier: BUSL-1.1
pragma solidity =0.7.6;

import './Constants.sol';

/// @title AdaptiveFee
/// @notice Calculates fee based on combination of sigmoids
library AdaptiveFee {
  // alpha1 + alpha2 + baseFee must be <= type(uint16).max
  struct Configuration {
    uint16 alpha1; // max value of the first sigmoid
    uint16 alpha2; // max value of the second sigmoid
    uint32 beta1; // shift along the x-axis for the first sigmoid
    uint32 beta2; // shift along the x-axis for the second sigmoid
    uint16 gamma1; // horizontal stretch factor for the first sigmoid
    uint16 gamma2; // horizontal stretch factor for the second sigmoid
    uint32 volumeBeta; // shift along the x-axis for the outer volume-sigmoid
    uint16 volumeGamma; // horizontal stretch factor the outer volume-sigmoid
    uint16 baseFee; // minimum possible fee
  }

  /// @notice Calculates fee based on formula:
  /// baseFee + sigmoidVolume(sigmoid1(volatility, volumePerLiquidity) + sigmoid2(volatility, volumePerLiquidity))
  /// maximum value capped by baseFee + alpha1 + alpha2
  function getFee(
    uint88 volatility,
    uint256 volumePerLiquidity,
    Configuration memory config
  ) internal pure returns (uint16 fee) {
    uint256 sumOfSigmoids = sigmoid(volatility, config.gamma1, config.alpha1, config.beta1) +
      sigmoid(volatility, config.gamma2, config.alpha2, config.beta2);

    if (sumOfSigmoids > type(uint16).max) {
      // should be impossible, just in case
      sumOfSigmoids = type(uint16).max;
    }

    return uint16(config.baseFee + sigmoid(volumePerLiquidity, config.volumeGamma, uint16(sumOfSigmoids), config.volumeBeta)); // safe since alpha1 + alpha2 + baseFee _must_ be <= type(uint16).max
  }

  /// @notice calculates α / (1 + e^( (β-x) / γ))
  /// that is a sigmoid with a maximum value of α, x-shifted by β, and stretched by γ
  /// @dev returns uint256 for fuzzy testing. Guaranteed that the result is not greater than alpha
  function sigmoid(
    uint256 x,
    uint16 g,
    uint16 alpha,
    uint256 beta
  ) internal pure returns (uint256 res) {
    if (x > beta) {
      x = x - beta;
      if (x >= 6 * uint256(g)) return alpha; // so x < 19 bits
      uint256 g8 = uint256(g)**8; // < 128 bits (8*16)
      uint256 ex = exp(x, g, g8); // < 155 bits
      res = (alpha * ex) / (g8 + ex); // in worst case: (16 + 155 bits) / 155 bits
      // so res <= alpha
    } else {
      x = beta - x;
      if (x >= 6 * uint256(g)) return 0; // so x < 19 bits
      uint256 g8 = uint256(g)**8; // < 128 bits (8*16)
      uint256 ex = g8 + exp(x, g, g8); // < 156 bits
      res = (alpha * g8) / ex; // in worst case: (16 + 128 bits) / 156 bits
      // g8 <= ex, so res <= alpha
    }
  }

  /// @notice calculates e^(x/g) * g^8 in a series, since (around zero):
  /// e^x = 1 + x + x^2/2 + ... + x^n/n! + ...
  /// e^(x/g) = 1 + x/g + x^2/(2*g^2) + ... + x^(n)/(g^n * n!) + ...
  function exp(
    uint256 x,
    uint16 g,
    uint256 gHighestDegree
  ) internal pure returns (uint256 res) {
    // calculating:
    // g**8 + x * g**7 + (x**2 * g**6) / 2 + (x**3 * g**5) / 6 + (x**4 * g**4) / 24 + (x**5 * g**3) / 120 + (x**6 * g^2) / 720 + x**7 * g / 5040 + x**8 / 40320

    // x**8 < 152 bits (19*8) and g**8 < 128 bits (8*16)
    // so each summand < 152 bits and res < 155 bits
    uint256 xLowestDegree = x;
    res = gHighestDegree; // g**8

    gHighestDegree /= g; // g**7
    res += xLowestDegree * gHighestDegree;

    gHighestDegree /= g; // g**6
    xLowestDegree *= x; // x**2
    res += (xLowestDegree * gHighestDegree) / 2;

    gHighestDegree /= g; // g**5
    xLowestDegree *= x; // x**3
    res += (xLowestDegree * gHighestDegree) / 6;

    gHighestDegree /= g; // g**4
    xLowestDegree *= x; // x**4
    res += (xLowestDegree * gHighestDegree) / 24;

    gHighestDegree /= g; // g**3
    xLowestDegree *= x; // x**5
    res += (xLowestDegree * gHighestDegree) / 120;

    gHighestDegree /= g; // g**2
    xLowestDegree *= x; // x**6
    res += (xLowestDegree * gHighestDegree) / 720;

    xLowestDegree *= x; // x**7
    res += (xLowestDegree * g) / 5040 + (xLowestDegree * x) / (40320);
  }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// 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 =0.7.6;

import '@cryptoalgebra/core/contracts/interfaces/IAlgebraPool.sol';
import './PoolAddress.sol';

/// @notice Provides validation for callbacks from Algebra Pools
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
library CallbackValidation {
    /// @notice Returns the address of a valid Algebra Pool
    /// @param poolDeployer The contract address of the Algebra pool deployer
    /// @param tokenA The contract address of either token0 or token1
    /// @param tokenB The contract address of the other token
    /// @return pool The V3 pool contract address
    function verifyCallback(
        address poolDeployer,
        address tokenA,
        address tokenB
    ) internal view returns (IAlgebraPool pool) {
        return verifyCallback(poolDeployer, PoolAddress.getPoolKey(tokenA, tokenB));
    }

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

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

/// @title Function for getting the current chain ID
library ChainId {
    /// @dev Gets the current chain ID
    /// @return chainId The current chain ID
    function get() internal pure returns (uint256 chainId) {
        assembly {
            chainId := chainid()
        }
    }
}

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

library Constants {
  uint8 internal constant RESOLUTION = 96;
  uint256 internal constant Q96 = 0x1000000000000000000000000;
  uint256 internal constant Q128 = 0x100000000000000000000000000000000;
  // fee value in hundredths of a bip, i.e. 1e-6
  uint16 internal constant BASE_FEE = 100;
  int24 internal constant MAX_TICK_SPACING = 500;

  // max(uint128) / (MAX_TICK - MIN_TICK)
  uint128 internal constant MAX_LIQUIDITY_PER_TICK = 191757638537527648490752896198553;

  uint32 internal constant MAX_LIQUIDITY_COOLDOWN = 1 days;
  uint8 internal constant MAX_COMMUNITY_FEE = 250;
  uint256 internal constant COMMUNITY_FEE_DENOMINATOR = 1000;
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

import "./IERC165.sol";

/**
 * @dev Implementation of the {IERC165} interface.
 *
 * Contracts may inherit from this and call {_registerInterface} to declare
 * their support of an interface.
 */
abstract contract ERC165 is IERC165 {
    /*
     * bytes4(keccak256('supportsInterface(bytes4)')) == 0x01ffc9a7
     */
    bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;

    /**
     * @dev Mapping of interface ids to whether or not it's supported.
     */
    mapping(bytes4 => bool) private _supportedInterfaces;

    constructor () {
        // Derived contracts need only register support for their own interfaces,
        // we register support for ERC165 itself here
        _registerInterface(_INTERFACE_ID_ERC165);
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     *
     * Time complexity O(1), guaranteed to always use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return _supportedInterfaces[interfaceId];
    }

    /**
     * @dev Registers the contract as an implementer of the interface defined by
     * `interfaceId`. Support of the actual ERC165 interface is automatic and
     * registering its interface id is not required.
     *
     * See {IERC165-supportsInterface}.
     *
     * Requirements:
     *
     * - `interfaceId` cannot be the ERC165 invalid interface (`0xffffffff`).
     */
    function _registerInterface(bytes4 interfaceId) internal virtual {
        require(interfaceId != 0xffffffff, "ERC165: invalid interface id");
        _supportedInterfaces[interfaceId] = true;
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

import "../../utils/Context.sol";
import "./IERC721.sol";
import "./IERC721Metadata.sol";
import "./IERC721Enumerable.sol";
import "./IERC721Receiver.sol";
import "../../introspection/ERC165.sol";
import "../../math/SafeMath.sol";
import "../../utils/Address.sol";
import "../../utils/EnumerableSet.sol";
import "../../utils/EnumerableMap.sol";
import "../../utils/Strings.sol";

/**
 * @title ERC721 Non-Fungible Token Standard basic implementation
 * @dev see https://eips.ethereum.org/EIPS/eip-721
 */
contract ERC721 is Context, ERC165, IERC721, IERC721Metadata, IERC721Enumerable {
    using SafeMath for uint256;
    using Address for address;
    using EnumerableSet for EnumerableSet.UintSet;
    using EnumerableMap for EnumerableMap.UintToAddressMap;
    using Strings for uint256;

    // Equals to `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`
    // which can be also obtained as `IERC721Receiver(0).onERC721Received.selector`
    bytes4 private constant _ERC721_RECEIVED = 0x150b7a02;

    // Mapping from holder address to their (enumerable) set of owned tokens
    mapping (address => EnumerableSet.UintSet) private _holderTokens;

    // Enumerable mapping from token ids to their owners
    EnumerableMap.UintToAddressMap private _tokenOwners;

    // Mapping from token ID to approved address
    mapping (uint256 => address) private _tokenApprovals;

    // Mapping from owner to operator approvals
    mapping (address => mapping (address => bool)) private _operatorApprovals;

    // Token name
    string private _name;

    // Token symbol
    string private _symbol;

    // Optional mapping for token URIs
    mapping (uint256 => string) private _tokenURIs;

    // Base URI
    string private _baseURI;

    /*
     *     bytes4(keccak256('balanceOf(address)')) == 0x70a08231
     *     bytes4(keccak256('ownerOf(uint256)')) == 0x6352211e
     *     bytes4(keccak256('approve(address,uint256)')) == 0x095ea7b3
     *     bytes4(keccak256('getApproved(uint256)')) == 0x081812fc
     *     bytes4(keccak256('setApprovalForAll(address,bool)')) == 0xa22cb465
     *     bytes4(keccak256('isApprovedForAll(address,address)')) == 0xe985e9c5
     *     bytes4(keccak256('transferFrom(address,address,uint256)')) == 0x23b872dd
     *     bytes4(keccak256('safeTransferFrom(address,address,uint256)')) == 0x42842e0e
     *     bytes4(keccak256('safeTransferFrom(address,address,uint256,bytes)')) == 0xb88d4fde
     *
     *     => 0x70a08231 ^ 0x6352211e ^ 0x095ea7b3 ^ 0x081812fc ^
     *        0xa22cb465 ^ 0xe985e9c5 ^ 0x23b872dd ^ 0x42842e0e ^ 0xb88d4fde == 0x80ac58cd
     */
    bytes4 private constant _INTERFACE_ID_ERC721 = 0x80ac58cd;

    /*
     *     bytes4(keccak256('name()')) == 0x06fdde03
     *     bytes4(keccak256('symbol()')) == 0x95d89b41
     *     bytes4(keccak256('tokenURI(uint256)')) == 0xc87b56dd
     *
     *     => 0x06fdde03 ^ 0x95d89b41 ^ 0xc87b56dd == 0x5b5e139f
     */
    bytes4 private constant _INTERFACE_ID_ERC721_METADATA = 0x5b5e139f;

    /*
     *     bytes4(keccak256('totalSupply()')) == 0x18160ddd
     *     bytes4(keccak256('tokenOfOwnerByIndex(address,uint256)')) == 0x2f745c59
     *     bytes4(keccak256('tokenByIndex(uint256)')) == 0x4f6ccce7
     *
     *     => 0x18160ddd ^ 0x2f745c59 ^ 0x4f6ccce7 == 0x780e9d63
     */
    bytes4 private constant _INTERFACE_ID_ERC721_ENUMERABLE = 0x780e9d63;

    /**
     * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
     */
    constructor (string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;

        // register the supported interfaces to conform to ERC721 via ERC165
        _registerInterface(_INTERFACE_ID_ERC721);
        _registerInterface(_INTERFACE_ID_ERC721_METADATA);
        _registerInterface(_INTERFACE_ID_ERC721_ENUMERABLE);
    }

    /**
     * @dev See {IERC721-balanceOf}.
     */
    function balanceOf(address owner) public view virtual override returns (uint256) {
        require(owner != address(0), "ERC721: balance query for the zero address");
        return _holderTokens[owner].length();
    }

    /**
     * @dev See {IERC721-ownerOf}.
     */
    function ownerOf(uint256 tokenId) public view virtual override returns (address) {
        return _tokenOwners.get(tokenId, "ERC721: owner query for nonexistent token");
    }

    /**
     * @dev See {IERC721Metadata-name}.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev See {IERC721Metadata-symbol}.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev See {IERC721Metadata-tokenURI}.
     */
    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
        require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token");

        string memory _tokenURI = _tokenURIs[tokenId];
        string memory base = baseURI();

        // If there is no base URI, return the token URI.
        if (bytes(base).length == 0) {
            return _tokenURI;
        }
        // If both are set, concatenate the baseURI and tokenURI (via abi.encodePacked).
        if (bytes(_tokenURI).length > 0) {
            return string(abi.encodePacked(base, _tokenURI));
        }
        // If there is a baseURI but no tokenURI, concatenate the tokenID to the baseURI.
        return string(abi.encodePacked(base, tokenId.toString()));
    }

    /**
    * @dev Returns the base URI set via {_setBaseURI}. This will be
    * automatically added as a prefix in {tokenURI} to each token's URI, or
    * to the token ID if no specific URI is set for that token ID.
    */
    function baseURI() public view virtual returns (string memory) {
        return _baseURI;
    }

    /**
     * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
     */
    function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) {
        return _holderTokens[owner].at(index);
    }

    /**
     * @dev See {IERC721Enumerable-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        // _tokenOwners are indexed by tokenIds, so .length() returns the number of tokenIds
        return _tokenOwners.length();
    }

    /**
     * @dev See {IERC721Enumerable-tokenByIndex}.
     */
    function tokenByIndex(uint256 index) public view virtual override returns (uint256) {
        (uint256 tokenId, ) = _tokenOwners.at(index);
        return tokenId;
    }

    /**
     * @dev See {IERC721-approve}.
     */
    function approve(address to, uint256 tokenId) public virtual override {
        address owner = ERC721.ownerOf(tokenId);
        require(to != owner, "ERC721: approval to current owner");

        require(_msgSender() == owner || ERC721.isApprovedForAll(owner, _msgSender()),
            "ERC721: approve caller is not owner nor approved for all"
        );

        _approve(to, tokenId);
    }

    /**
     * @dev See {IERC721-getApproved}.
     */
    function getApproved(uint256 tokenId) public view virtual override returns (address) {
        require(_exists(tokenId), "ERC721: approved query for nonexistent token");

        return _tokenApprovals[tokenId];
    }

    /**
     * @dev See {IERC721-setApprovalForAll}.
     */
    function setApprovalForAll(address operator, bool approved) public virtual override {
        require(operator != _msgSender(), "ERC721: approve to caller");

        _operatorApprovals[_msgSender()][operator] = approved;
        emit ApprovalForAll(_msgSender(), operator, approved);
    }

    /**
     * @dev See {IERC721-isApprovedForAll}.
     */
    function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
        return _operatorApprovals[owner][operator];
    }

    /**
     * @dev See {IERC721-transferFrom}.
     */
    function transferFrom(address from, address to, uint256 tokenId) public virtual override {
        //solhint-disable-next-line max-line-length
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");

        _transfer(from, to, tokenId);
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(address from, address to, uint256 tokenId) public virtual override {
        safeTransferFrom(from, to, tokenId, "");
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory _data) public virtual override {
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
        _safeTransfer(from, to, tokenId, _data);
    }

    /**
     * @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.
     *
     * `_data` is additional data, it has no specified format and it is sent in call to `to`.
     *
     * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
     * implement alternative mechanisms to perform token transfer, such as signature-based.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function _safeTransfer(address from, address to, uint256 tokenId, bytes memory _data) internal virtual {
        _transfer(from, to, tokenId);
        require(_checkOnERC721Received(from, to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
    }

    /**
     * @dev Returns whether `tokenId` exists.
     *
     * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
     *
     * Tokens start existing when they are minted (`_mint`),
     * and stop existing when they are burned (`_burn`).
     */
    function _exists(uint256 tokenId) internal view virtual returns (bool) {
        return _tokenOwners.contains(tokenId);
    }

    /**
     * @dev Returns whether `spender` is allowed to manage `tokenId`.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
        require(_exists(tokenId), "ERC721: operator query for nonexistent token");
        address owner = ERC721.ownerOf(tokenId);
        return (spender == owner || getApproved(tokenId) == spender || ERC721.isApprovedForAll(owner, spender));
    }

    /**
     * @dev Safely mints `tokenId` and transfers it to `to`.
     *
     * Requirements:
     d*
     * - `tokenId` must not exist.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function _safeMint(address to, uint256 tokenId) internal virtual {
        _safeMint(to, tokenId, "");
    }

    /**
     * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
     * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
     */
    function _safeMint(address to, uint256 tokenId, bytes memory _data) internal virtual {
        _mint(to, tokenId);
        require(_checkOnERC721Received(address(0), to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
    }

    /**
     * @dev Mints `tokenId` and transfers it to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
     *
     * Requirements:
     *
     * - `tokenId` must not exist.
     * - `to` cannot be the zero address.
     *
     * Emits a {Transfer} event.
     */
    function _mint(address to, uint256 tokenId) internal virtual {
        require(to != address(0), "ERC721: mint to the zero address");
        require(!_exists(tokenId), "ERC721: token already minted");

        _beforeTokenTransfer(address(0), to, tokenId);

        _holderTokens[to].add(tokenId);

        _tokenOwners.set(tokenId, to);

        emit Transfer(address(0), to, tokenId);
    }

    /**
     * @dev Destroys `tokenId`.
     * The approval is cleared when the token is burned.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     *
     * Emits a {Transfer} event.
     */
    function _burn(uint256 tokenId) internal virtual {
        address owner = ERC721.ownerOf(tokenId); // internal owner

        _beforeTokenTransfer(owner, address(0), tokenId);

        // Clear approvals
        _approve(address(0), tokenId);

        // Clear metadata (if any)
        if (bytes(_tokenURIs[tokenId]).length != 0) {
            delete _tokenURIs[tokenId];
        }

        _holderTokens[owner].remove(tokenId);

        _tokenOwners.remove(tokenId);

        emit Transfer(owner, address(0), tokenId);
    }

    /**
     * @dev Transfers `tokenId` from `from` to `to`.
     *  As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     *
     * Emits a {Transfer} event.
     */
    function _transfer(address from, address to, uint256 tokenId) internal virtual {
        require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer of token that is not own"); // internal owner
        require(to != address(0), "ERC721: transfer to the zero address");

        _beforeTokenTransfer(from, to, tokenId);

        // Clear approvals from the previous owner
        _approve(address(0), tokenId);

        _holderTokens[from].remove(tokenId);
        _holderTokens[to].add(tokenId);

        _tokenOwners.set(tokenId, to);

        emit Transfer(from, to, tokenId);
    }

    /**
     * @dev Sets `_tokenURI` as the tokenURI of `tokenId`.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function _setTokenURI(uint256 tokenId, string memory _tokenURI) internal virtual {
        require(_exists(tokenId), "ERC721Metadata: URI set of nonexistent token");
        _tokenURIs[tokenId] = _tokenURI;
    }

    /**
     * @dev Internal function to set the base URI for all token IDs. It is
     * automatically added as a prefix to the value returned in {tokenURI},
     * or to the token ID if {tokenURI} is empty.
     */
    function _setBaseURI(string memory baseURI_) internal virtual {
        _baseURI = baseURI_;
    }

    /**
     * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
     * The call is not executed if the target address is not a contract.
     *
     * @param from address representing the previous owner of the given token ID
     * @param to target address that will receive the tokens
     * @param tokenId uint256 ID of the token to be transferred
     * @param _data bytes optional data to send along with the call
     * @return bool whether the call correctly returned the expected magic value
     */
    function _checkOnERC721Received(address from, address to, uint256 tokenId, bytes memory _data)
        private returns (bool)
    {
        if (!to.isContract()) {
            return true;
        }
        bytes memory returndata = to.functionCall(abi.encodeWithSelector(
            IERC721Receiver(to).onERC721Received.selector,
            _msgSender(),
            from,
            tokenId,
            _data
        ), "ERC721: transfer to non ERC721Receiver implementer");
        bytes4 retval = abi.decode(returndata, (bytes4));
        return (retval == _ERC721_RECEIVED);
    }

    /**
     * @dev Approve `to` to operate on `tokenId`
     *
     * Emits an {Approval} event.
     */
    function _approve(address to, uint256 tokenId) internal virtual {
        _tokenApprovals[tokenId] = to;
        emit Approval(ERC721.ownerOf(tokenId), to, tokenId); // internal owner
    }

    /**
     * @dev Hook that is called before any token transfer. This includes minting
     * and burning.
     *
     * Calling conditions:
     *
     * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
     * transferred to `to`.
     * - When `from` is zero, `tokenId` will be minted for `to`.
     * - When `to` is zero, ``from``'s `tokenId` will be burned.
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 tokenId) internal virtual { }
}

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

import '@openzeppelin/contracts/token/ERC721/ERC721.sol';
import '@openzeppelin/contracts/utils/Address.sol';

import '../libraries/ChainId.sol';
import '../interfaces/external/IERC1271.sol';
import '../interfaces/IERC721Permit.sol';
import './BlockTimestamp.sol';

/// @title ERC721 with permit
/// @notice Nonfungible tokens that support an approve via signature, i.e. permit
abstract contract ERC721Permit is BlockTimestamp, ERC721, IERC721Permit {
    /// @dev Gets the current nonce for a token ID and then increments it, returning the original value
    function _getAndIncrementNonce(uint256 tokenId) internal virtual returns (uint256);

    /// @dev The hash of the name used in the permit signature verification
    bytes32 private immutable nameHash;

    /// @dev The hash of the version string used in the permit signature verification
    bytes32 private immutable versionHash;

    /// @notice Computes the nameHash and versionHash
    constructor(
        string memory name_,
        string memory symbol_,
        string memory version_
    ) ERC721(name_, symbol_) {
        nameHash = keccak256(bytes(name_));
        versionHash = keccak256(bytes(version_));
    }

    /// @inheritdoc IERC721Permit
    function DOMAIN_SEPARATOR() public view override returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    // keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)')
                    0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f,
                    nameHash,
                    versionHash,
                    ChainId.get(),
                    address(this)
                )
            );
    }

    /// @inheritdoc IERC721Permit
    /// @dev Value is equal to keccak256("Permit(address spender,uint256 tokenId,uint256 nonce,uint256 deadline)");
    bytes32 public constant override PERMIT_TYPEHASH =
        0x49ecf333e5b8c95c40fdafc95c1ad136e8914a8fb55e9dc8bb01eaa83a2df9ad;

    /// @inheritdoc IERC721Permit
    function permit(
        address spender,
        uint256 tokenId,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external payable override {
        require(_blockTimestamp() <= deadline, 'Permit expired');

        bytes32 digest = keccak256(
            abi.encodePacked(
                '\x19\x01',
                DOMAIN_SEPARATOR(),
                keccak256(abi.encode(PERMIT_TYPEHASH, spender, tokenId, _getAndIncrementNonce(tokenId), deadline))
            )
        );
        address owner = ownerOf(tokenId);
        require(spender != owner, 'ERC721Permit: approval to current owner');

        if (Address.isContract(owner)) {
            require(IERC1271(owner).isValidSignature(digest, abi.encodePacked(r, s, v)) == 0x1626ba7e, 'Unauthorized');
        } else {
            address recoveredAddress = ecrecover(digest, v, r, s);
            require(recoveredAddress != address(0), 'Invalid signature');
            require(recoveredAddress == owner, 'Unauthorized');
        }

        _approve(spender, tokenId);
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

/**
 * @dev Library for managing an enumerable variant of Solidity's
 * https://solidity.readthedocs.io/en/latest/types.html#mapping-types[`mapping`]
 * type.
 *
 * Maps have the following properties:
 *
 * - Entries are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Entries are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableMap for EnumerableMap.UintToAddressMap;
 *
 *     // Declare a set state variable
 *     EnumerableMap.UintToAddressMap private myMap;
 * }
 * ```
 *
 * As of v3.0.0, only maps of type `uint256 -> address` (`UintToAddressMap`) are
 * supported.
 */
library EnumerableMap {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Map type with
    // bytes32 keys and values.
    // The Map implementation uses private functions, and user-facing
    // implementations (such as Uint256ToAddressMap) are just wrappers around
    // the underlying Map.
    // This means that we can only create new EnumerableMaps for types that fit
    // in bytes32.

    struct MapEntry {
        bytes32 _key;
        bytes32 _value;
    }

    struct Map {
        // Storage of map keys and values
        MapEntry[] _entries;

        // Position of the entry defined by a key in the `entries` array, plus 1
        // because index 0 means a key is not in the map.
        mapping (bytes32 => uint256) _indexes;
    }

    /**
     * @dev Adds a key-value pair to a map, or updates the value for an existing
     * key. O(1).
     *
     * Returns true if the key was added to the map, that is if it was not
     * already present.
     */
    function _set(Map storage map, bytes32 key, bytes32 value) private returns (bool) {
        // We read and store the key's index to prevent multiple reads from the same storage slot
        uint256 keyIndex = map._indexes[key];

        if (keyIndex == 0) { // Equivalent to !contains(map, key)
            map._entries.push(MapEntry({ _key: key, _value: value }));
            // The entry is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            map._indexes[key] = map._entries.length;
            return true;
        } else {
            map._entries[keyIndex - 1]._value = value;
            return false;
        }
    }

    /**
     * @dev Removes a key-value pair from a map. O(1).
     *
     * Returns true if the key was removed from the map, that is if it was present.
     */
    function _remove(Map storage map, bytes32 key) private returns (bool) {
        // We read and store the key's index to prevent multiple reads from the same storage slot
        uint256 keyIndex = map._indexes[key];

        if (keyIndex != 0) { // Equivalent to contains(map, key)
            // To delete a key-value pair from the _entries array in O(1), we swap the entry to delete with the last one
            // in the array, and then remove the last entry (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.

            uint256 toDeleteIndex = keyIndex - 1;
            uint256 lastIndex = map._entries.length - 1;

            // When the entry to delete is the last one, the swap operation is unnecessary. However, since this occurs
            // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.

            MapEntry storage lastEntry = map._entries[lastIndex];

            // Move the last entry to the index where the entry to delete is
            map._entries[toDeleteIndex] = lastEntry;
            // Update the index for the moved entry
            map._indexes[lastEntry._key] = toDeleteIndex + 1; // All indexes are 1-based

            // Delete the slot where the moved entry was stored
            map._entries.pop();

            // Delete the index for the deleted slot
            delete map._indexes[key];

            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Returns true if the key is in the map. O(1).
     */
    function _contains(Map storage map, bytes32 key) private view returns (bool) {
        return map._indexes[key] != 0;
    }

    /**
     * @dev Returns the number of key-value pairs in the map. O(1).
     */
    function _length(Map storage map) private view returns (uint256) {
        return map._entries.length;
    }

   /**
    * @dev Returns the key-value pair stored at position `index` in the map. O(1).
    *
    * Note that there are no guarantees on the ordering of entries inside the
    * array, and it may change when more entries are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function _at(Map storage map, uint256 index) private view returns (bytes32, bytes32) {
        require(map._entries.length > index, "EnumerableMap: index out of bounds");

        MapEntry storage entry = map._entries[index];
        return (entry._key, entry._value);
    }

    /**
     * @dev Tries to returns the value associated with `key`.  O(1).
     * Does not revert if `key` is not in the map.
     */
    function _tryGet(Map storage map, bytes32 key) private view returns (bool, bytes32) {
        uint256 keyIndex = map._indexes[key];
        if (keyIndex == 0) return (false, 0); // Equivalent to contains(map, key)
        return (true, map._entries[keyIndex - 1]._value); // All indexes are 1-based
    }

    /**
     * @dev Returns the value associated with `key`.  O(1).
     *
     * Requirements:
     *
     * - `key` must be in the map.
     */
    function _get(Map storage map, bytes32 key) private view returns (bytes32) {
        uint256 keyIndex = map._indexes[key];
        require(keyIndex != 0, "EnumerableMap: nonexistent key"); // Equivalent to contains(map, key)
        return map._entries[keyIndex - 1]._value; // All indexes are 1-based
    }

    /**
     * @dev Same as {_get}, with a custom error message when `key` is not in the map.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {_tryGet}.
     */
    function _get(Map storage map, bytes32 key, string memory errorMessage) private view returns (bytes32) {
        uint256 keyIndex = map._indexes[key];
        require(keyIndex != 0, errorMessage); // Equivalent to contains(map, key)
        return map._entries[keyIndex - 1]._value; // All indexes are 1-based
    }

    // UintToAddressMap

    struct UintToAddressMap {
        Map _inner;
    }

    /**
     * @dev Adds a key-value pair to a map, or updates the value for an existing
     * key. O(1).
     *
     * Returns true if the key was added to the map, that is if it was not
     * already present.
     */
    function set(UintToAddressMap storage map, uint256 key, address value) internal returns (bool) {
        return _set(map._inner, bytes32(key), bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the key was removed from the map, that is if it was present.
     */
    function remove(UintToAddressMap storage map, uint256 key) internal returns (bool) {
        return _remove(map._inner, bytes32(key));
    }

    /**
     * @dev Returns true if the key is in the map. O(1).
     */
    function contains(UintToAddressMap storage map, uint256 key) internal view returns (bool) {
        return _contains(map._inner, bytes32(key));
    }

    /**
     * @dev Returns the number of elements in the map. O(1).
     */
    function length(UintToAddressMap storage map) internal view returns (uint256) {
        return _length(map._inner);
    }

   /**
    * @dev Returns the element stored at position `index` in the set. O(1).
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(UintToAddressMap storage map, uint256 index) internal view returns (uint256, address) {
        (bytes32 key, bytes32 value) = _at(map._inner, index);
        return (uint256(key), address(uint160(uint256(value))));
    }

    /**
     * @dev Tries to returns the value associated with `key`.  O(1).
     * Does not revert if `key` is not in the map.
     *
     * _Available since v3.4._
     */
    function tryGet(UintToAddressMap storage map, uint256 key) internal view returns (bool, address) {
        (bool success, bytes32 value) = _tryGet(map._inner, bytes32(key));
        return (success, address(uint160(uint256(value))));
    }

    /**
     * @dev Returns the value associated with `key`.  O(1).
     *
     * Requirements:
     *
     * - `key` must be in the map.
     */
    function get(UintToAddressMap storage map, uint256 key) internal view returns (address) {
        return address(uint160(uint256(_get(map._inner, bytes32(key)))));
    }

    /**
     * @dev Same as {get}, with a custom error message when `key` is not in the map.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryGet}.
     */
    function get(UintToAddressMap storage map, uint256 key, string memory errorMessage) internal view returns (address) {
        return address(uint160(uint256(_get(map._inner, bytes32(key), errorMessage))));
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.

    struct Set {
        // Storage of set values
        bytes32[] _values;

        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping (bytes32 => uint256) _indexes;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];

        if (valueIndex != 0) { // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.

            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;

            // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
            // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.

            bytes32 lastvalue = set._values[lastIndex];

            // Move the last value to the index where the value to delete is
            set._values[toDeleteIndex] = lastvalue;
            // Update the index for the moved value
            set._indexes[lastvalue] = toDeleteIndex + 1; // All indexes are 1-based

            // Delete the slot where the moved value was stored
            set._values.pop();

            // Delete the index for the deleted slot
            delete set._indexes[value];

            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        require(set._values.length > index, "EnumerableSet: index out of bounds");
        return set._values[index];
    }

    // Bytes32Set

    struct Bytes32Set {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _add(set._inner, value);
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _remove(set._inner, value);
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
        return _contains(set._inner, value);
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(Bytes32Set storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
        return _at(set._inner, index);
    }

    // AddressSet

    struct AddressSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint160(uint256(_at(set._inner, index))));
    }


    // UintSet

    struct UintSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.4.0 || ^0.5.0 || ^0.6.0 || ^0.7.0;

/// @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 = a * b; // Least significant 256 bits of the product
    uint256 prod1; // Most significant 256 bits of the product
    assembly {
      let mm := mulmod(a, b, not(0))
      prod1 := sub(sub(mm, prod0), lt(mm, prod0))
    }

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

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

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

    // Make division exact by subtracting the remainder from [prod1 prod0]
    // Compute remainder using mulmod
    // Subtract 256 bit remainder from 512 bit number
    assembly {
      let remainder := mulmod(a, b, denominator)
      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 preconditions 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) {
    if (a == 0 || ((result = a * b) / a == b)) {
      require(denominator > 0);
      assembly {
        result := add(div(result, denominator), gt(mod(result, denominator), 0))
      }
    } else {
      result = mulDiv(a, b, denominator);
      if (mulmod(a, b, denominator) > 0) {
        require(result < type(uint256).max);
        result++;
      }
    }
  }

  /// @notice Returns ceil(x / y)
  /// @dev division by 0 has unspecified behavior, and must be checked externally
  /// @param x The dividend
  /// @param y The divisor
  /// @return z The quotient, ceil(x / y)
  function divRoundingUp(uint256 x, uint256 y) internal pure returns (uint256 z) {
    assembly {
      z := add(div(x, y), gt(mod(x, y), 0))
    }
  }
}

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

/**
 * @title The interface for the Algebra Factory
 * @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
 * https://github.com/Uniswap/v3-core/tree/main/contracts/interfaces
 */
interface IAlgebraFactory {
  /**
   * @notice Emitted when the owner of the factory is changed
   * @param newOwner The owner after the owner was changed
   */
  event Owner(address indexed newOwner);

  /**
   * @notice Emitted when the vault address is changed
   * @param newVaultAddress The vault address after the address was changed
   */
  event VaultAddress(address indexed newVaultAddress);

  /**
   * @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 pool The address of the created pool
   */
  event Pool(address indexed token0, address indexed token1, address pool);

  /**
   * @notice Emitted when the farming address is changed
   * @param newFarmingAddress The farming address after the address was changed
   */
  event FarmingAddress(address indexed newFarmingAddress);

  /**
   * @notice Emitted when the default community fee is changed
   * @param newDefaultCommunityFee The new default community fee value
   */
  event DefaultCommunityFee(uint8 newDefaultCommunityFee);

  event FeeConfiguration(
    uint16 alpha1,
    uint16 alpha2,
    uint32 beta1,
    uint32 beta2,
    uint16 gamma1,
    uint16 gamma2,
    uint32 volumeBeta,
    uint16 volumeGamma,
    uint16 baseFee
  );

  /**
   * @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 current poolDeployerAddress
   * @return The address of the poolDeployer
   */
  function poolDeployer() external view returns (address);

  /**
   * @dev Is retrieved from the pools to restrict calling
   * certain functions not by a tokenomics contract
   * @return The tokenomics contract address
   */
  function farmingAddress() external view returns (address);

  /**
   * @notice Returns the default community fee
   * @return Fee which will be set at the creation of the pool
   */
  function defaultCommunityFee() external view returns (uint8);

  function vaultAddress() external view returns (address);

  /**
   * @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
   * @return pool The pool address
   */
  function poolByPair(address tokenA, address tokenB) 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
   * @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) 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;

  /**
   * @dev updates tokenomics address on the factory
   * @param _farmingAddress The new tokenomics contract address
   */
  function setFarmingAddress(address _farmingAddress) external;

  /**
   * @dev updates default community fee for new pools
   * @param newDefaultCommunityFee The new community fee, _must_ be <= MAX_COMMUNITY_FEE
   */
  function setDefaultCommunityFee(uint8 newDefaultCommunityFee) external;

  /**
   * @dev updates vault address on the factory
   * @param _vaultAddress The new vault contract address
   */
  function setVaultAddress(address _vaultAddress) external;

  /**
   * @notice Changes initial fee configuration for new pools
   * @dev changes coefficients for sigmoids: α / (1 + e^( (β-x) / γ))
   * alpha1 + alpha2 + baseFee (max possible fee) must be <= type(uint16).max
   * gammas must be > 0
   * @param alpha1 max value of the first sigmoid
   * @param alpha2 max value of the second sigmoid
   * @param beta1 shift along the x-axis for the first sigmoid
   * @param beta2 shift along the x-axis for the second sigmoid
   * @param gamma1 horizontal stretch factor for the first sigmoid
   * @param gamma2 horizontal stretch factor for the second sigmoid
   * @param volumeBeta shift along the x-axis for the outer volume-sigmoid
   * @param volumeGamma horizontal stretch factor the outer volume-sigmoid
   * @param baseFee minimum possible fee
   */
  function setBaseFeeConfiguration(
    uint16 alpha1,
    uint16 alpha2,
    uint32 beta1,
    uint32 beta2,
    uint16 gamma1,
    uint16 gamma2,
    uint32 volumeBeta,
    uint16 volumeGamma,
    uint16 baseFee
  ) external;
}

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

/// @title Callback for IAlgebraPoolActions#mint
/// @notice Any contract that calls IAlgebraPoolActions#mint must implement this interface
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-core/tree/main/contracts/interfaces
interface IAlgebraMintCallback {
  /// @notice Called to `msg.sender` after minting liquidity to a position from IAlgebraPool#mint.
  /// @dev In the implementation you must pay the pool tokens owed for the minted liquidity.
  /// The caller of this method must be checked to be a AlgebraPool deployed by the canonical AlgebraFactory.
  /// @param amount0Owed The amount of token0 due to the pool for the minted liquidity
  /// @param amount1Owed The amount of token1 due to the pool for the minted liquidity
  /// @param data Any data passed through by the caller via the IAlgebraPoolActions#mint call
  function algebraMintCallback(
    uint256 amount0Owed,
    uint256 amount1Owed,
    bytes calldata data
  ) external;
}

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

import './pool/IAlgebraPoolImmutables.sol';
import './pool/IAlgebraPoolState.sol';
import './pool/IAlgebraPoolDerivedState.sol';
import './pool/IAlgebraPoolActions.sol';
import './pool/IAlgebraPoolPermissionedActions.sol';
import './pool/IAlgebraPoolEvents.sol';

/**
 * @title The interface for a Algebra Pool
 * @dev The pool interface is broken up into many smaller pieces.
 * Credit to Uniswap Labs under GPL-2.0-or-later license:
 * https://github.com/Uniswap/v3-core/tree/main/contracts/interfaces
 */
interface IAlgebraPool is
  IAlgebraPoolImmutables,
  IAlgebraPoolState,
  IAlgebraPoolDerivedState,
  IAlgebraPoolActions,
  IAlgebraPoolPermissionedActions,
  IAlgebraPoolEvents
{
  // used only for combining interfaces
}

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

/// @title Permissionless pool actions
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-core/tree/main/contracts/interfaces
interface IAlgebraPoolActions {
  /**
   * @notice Sets the initial price for the pool
   * @dev Price is represented as a sqrt(amountToken1/amountToken0) Q64.96 value
   * @param price the initial sqrt price of the pool as a Q64.96
   */
  function initialize(uint160 price) external;

  /**
   * @notice Adds liquidity for the given recipient/bottomTick/topTick position
   * @dev The caller of this method receives a callback in the form of IAlgebraMintCallback# AlgebraMintCallback
   * in which they must pay any token0 or token1 owed for the liquidity. The amount of token0/token1 due depends
   * on bottomTick, topTick, the amount of liquidity, and the current price.
   * @param sender The address which will receive potential surplus of paid tokens
   * @param recipient The address for which the liquidity will be created
   * @param bottomTick The lower tick of the position in which to add liquidity
   * @param topTick The upper tick of the position in which to add liquidity
   * @param amount The desired 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
   * @return liquidityActual The actual minted amount of liquidity
   */
  function mint(
    address sender,
    address recipient,
    int24 bottomTick,
    int24 topTick,
    uint128 amount,
    bytes calldata data
  )
    external
    returns (
      uint256 amount0,
      uint256 amount1,
      uint128 liquidityActual
    );

  /**
   * @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 bottomTick The lower tick of the position for which to collect fees
   * @param topTick 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 bottomTick,
    int24 topTick,
    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 bottomTick The lower tick of the position for which to burn liquidity
   * @param topTick 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 bottomTick,
    int24 topTick,
    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 IAlgebraSwapCallback# AlgebraSwapCallback
   * @param recipient The address to receive the output of the swap
   * @param zeroToOne 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 limitSqrtPrice 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. If using the Router it should contain
   * SwapRouter#SwapCallbackData
   * @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 zeroToOne,
    int256 amountSpecified,
    uint160 limitSqrtPrice,
    bytes calldata data
  ) external returns (int256 amount0, int256 amount1);

  /**
   * @notice Swap token0 for token1, or token1 for token0 (tokens that have fee on transfer)
   * @dev The caller of this method receives a callback in the form of I AlgebraSwapCallback# AlgebraSwapCallback
   * @param sender The address called this function (Comes from the Router)
   * @param recipient The address to receive the output of the swap
   * @param zeroToOne 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 limitSqrtPrice 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. If using the Router it should contain
   * SwapRouter#SwapCallbackData
   * @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 swapSupportingFeeOnInputTokens(
    address sender,
    address recipient,
    bool zeroToOne,
    int256 amountSpecified,
    uint160 limitSqrtPrice,
    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 IAlgebraFlashCallback# AlgebraFlashCallback
   * @dev All excess tokens paid in the callback are distributed to liquidity providers as an additional fee. So this method can be used
   * to donate underlying tokens 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;
}

// 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.
 * @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
 * https://github.com/Uniswap/v3-core/tree/main/contracts/interfaces
 */
interface IAlgebraPoolDerivedState {
  /**
   * @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 secondsPerLiquidityCumulatives Cumulative seconds per liquidity-in-range value as of each `secondsAgos`
   * from the current block timestamp
   * @return volatilityCumulatives Cumulative standard deviation as of each `secondsAgos`
   * @return volumePerAvgLiquiditys Cumulative swap volume per liquidity as of each `secondsAgos`
   */
  function getTimepoints(uint32[] calldata secondsAgos)
    external
    view
    returns (
      int56[] memory tickCumulatives,
      uint160[] memory secondsPerLiquidityCumulatives,
      uint112[] memory volatilityCumulatives,
      uint256[] memory volumePerAvgLiquiditys
    );

  /**
   * @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 bottomTick The lower tick of the range
   * @param topTick The upper tick of the range
   * @return innerTickCumulative The snapshot of the tick accumulator for the range
   * @return innerSecondsSpentPerLiquidity The snapshot of seconds per liquidity for the range
   * @return innerSecondsSpent The snapshot of the number of seconds during which the price was in this range
   */
  function getInnerCumulatives(int24 bottomTick, int24 topTick)
    external
    view
    returns (
      int56 innerTickCumulative,
      uint160 innerSecondsSpentPerLiquidity,
      uint32 innerSecondsSpent
    );
}

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

/// @title Events emitted by a pool
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-core/tree/main/contracts/interfaces
interface IAlgebraPoolEvents {
  /**
   * @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 price 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 price, 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 bottomTick The lower tick of the position
   * @param topTick The upper tick of the position
   * @param liquidityAmount 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 bottomTick,
    int24 indexed topTick,
    uint128 liquidityAmount,
    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 recipient The address that received fees
   * @param bottomTick The lower tick of the position
   * @param topTick 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 bottomTick, int24 indexed topTick, 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 bottomTick The lower tick of the position
   * @param topTick The upper tick of the position
   * @param liquidityAmount 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 bottomTick, int24 indexed topTick, uint128 liquidityAmount, 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 price 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 price, 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 when the community fee is changed by the pool
   * @param communityFee0New The updated value of the token0 community fee percent
   * @param communityFee1New The updated value of the token1 community fee percent
   */
  event CommunityFee(uint8 communityFee0New, uint8 communityFee1New);

  /**
   * @notice Emitted when the tick spacing changes
   * @param newTickSpacing The updated value of the new tick spacing
   */
  event TickSpacing(int24 newTickSpacing);

  /**
   * @notice Emitted when new activeIncentive is set
   * @param virtualPoolAddress The address of a virtual pool associated with the current active incentive
   */
  event Incentive(address indexed virtualPoolAddress);

  /**
   * @notice Emitted when the fee changes
   * @param feeZto The value of the token fee for zto swaps
   * @param feeOtz The value of the token fee for otz swaps
   */
  event Fee(uint16 feeZto, uint16 feeOtz);

  /**
   * @notice Emitted when the LiquidityCooldown changes
   * @param liquidityCooldown The value of locktime for added liquidity
   */
  event LiquidityCooldown(uint32 liquidityCooldown);
}

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

import '../IDataStorageOperator.sol';

/// @title Pool state that never changes
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-core/tree/main/contracts/interfaces
interface IAlgebraPoolImmutables {
  /**
   * @notice The contract that stores all the timepoints and can perform actions with them
   * @return The operator address
   */
  function dataStorageOperator() external view returns (address);

  /**
   * @notice The contract that deployed the pool, which must adhere to the IAlgebraFactory 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 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: 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 or tokenomics
 * @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
 * https://github.com/Uniswap/v3-core/tree/main/contracts/interfaces
 */
interface IAlgebraPoolPermissionedActions {
  /**
   * @notice Set the community's % share of the fees. Cannot exceed 25% (250)
   * @param communityFee0 new community fee percent for token0 of the pool in thousandths (1e-3)
   * @param communityFee1 new community fee percent for token1 of the pool in thousandths (1e-3)
   */
  function setCommunityFee(uint8 communityFee0, uint8 communityFee1) external;

  /// @notice Set the new tick spacing values. Only factory owner
  /// @param newTickSpacing The new tick spacing value
  function setTickSpacing(int24 newTickSpacing) external;

  /**
   * @notice Sets an active incentive
   * @param virtualPoolAddress The address of a virtual pool associated with the incentive
   */
  function setIncentive(address virtualPoolAddress) external;

  /**
   * @notice Sets new lock time for added liquidity
   * @param newLiquidityCooldown The time in seconds
   */
  function setLiquidityCooldown(uint32 newLiquidityCooldown) external;
}

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

/// @title Pool state that can change
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-core/tree/main/contracts/interfaces
interface IAlgebraPoolState {
  /**
   * @notice The globalState structure in the pool stores many values but requires only one slot
   * and is exposed as a single method to save gas when accessed externally.
   * @return price The current price of the pool as a sqrt(token1/token0) Q64.96 value;
   * Returns tick The current tick of the pool, i.e. according to the last tick transition that was run;
   * Returns This value may not always be equal to SqrtTickMath.getTickAtSqrtRatio(price) if the price is on a tick
   * boundary;
   * Returns feeZto The last pool fee value for ZtO swaps in hundredths of a bip, i.e. 1e-6;
   * Returns feeOtz The last pool fee value for OtZ swaps in hundredths of a bip, i.e. 1e-6;
   * Returns timepointIndex The index of the last written timepoint;
   * Returns communityFeeToken0 The community fee percentage of the swap fee in thousandths (1e-3) for token0;
   * Returns communityFeeToken1 The community fee percentage of the swap fee in thousandths (1e-3) for token1;
   * Returns unlocked Whether the pool is currently locked to reentrancy;
   */
  function globalState()
    external
    view
    returns (
      uint160 price,
      int24 tick,
      uint16 feeZto,
      uint16 feeOtz,
      uint16 timepointIndex,
      uint8 communityFeeToken0,
      uint8 communityFeeToken1,
      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 totalFeeGrowth0Token() 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 totalFeeGrowth1Token() external view returns (uint256);

  /**
   * @notice The currently in range liquidity available to the pool
   * @dev This value has no relationship to the total liquidity across all ticks.
   * Returned value cannot exceed type(uint128).max
   */
  function liquidity() external view returns (uint128);

  /**
   * @notice Look up information about a specific tick in the pool
   * @dev This is a public structure, so the `return` natspec tags are omitted.
   * @param tick The tick to look up
   * @return liquidityTotal the total amount of position liquidity that uses the pool either as tick lower or
   * tick upper;
   * Returns liquidityDelta how much liquidity changes when the pool price crosses the tick;
   * Returns outerFeeGrowth0Token the fee growth on the other side of the tick from the current tick in token0;
   * Returns outerFeeGrowth1Token the fee growth on the other side of the tick from the current tick in token1;
   * Returns outerTickCumulative the cumulative tick value on the other side of the tick from the current tick;
   * Returns outerSecondsPerLiquidity the seconds spent per liquidity on the other side of the tick from the current tick;
   * Returns outerSecondsSpent the seconds spent on the other side of the tick from the current tick;
   * Returns initialized Set to true if the tick is initialized, i.e. liquidityTotal is greater than 0
   * otherwise equal to false. Outside values can only be used if the tick is initialized.
   * 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 liquidityTotal,
      int128 liquidityDelta,
      uint256 outerFeeGrowth0Token,
      uint256 outerFeeGrowth1Token,
      int56 outerTickCumulative,
      uint160 outerSecondsPerLiquidity,
      uint32 outerSecondsSpent,
      bool initialized
    );

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

  /**
   * @notice Returns the information about a position by the position's key
   * @dev This is a public mapping of structures, so the `return` natspec tags are omitted.
   * @param key The position's key is a hash of a preimage composed by the owner, bottomTick and topTick
   * @return liquidityAmount The amount of liquidity in the position;
   * Returns lastLiquidityAddTimestamp Timestamp of last adding of liquidity;
   * Returns innerFeeGrowth0Token Fee growth of token0 inside the tick range as of the last mint/burn/poke;
   * Returns innerFeeGrowth1Token Fee growth of token1 inside the tick range as of the last mint/burn/poke;
   * Returns fees0 The computed amount of token0 owed to the position as of the last mint/burn/poke;
   * Returns fees1 The computed amount of token1 owed to the position as of the last mint/burn/poke
   */
  function positions(bytes32 key)
    external
    view
    returns (
      uint128 liquidityAmount,
      uint32 lastLiquidityAddTimestamp,
      uint256 innerFeeGrowth0Token,
      uint256 innerFeeGrowth1Token,
      uint128 fees0,
      uint128 fees1
    );

  /**
   * @notice Returns data about a specific timepoint index
   * @param index The element of the timepoints array to fetch
   * @dev You most likely want to use #getTimepoints() instead of this method to get an timepoint as of some amount of time
   * ago, rather than at a specific index in the array.
   * This is a public mapping of structures, so the `return` natspec tags are omitted.
   * @return initialized whether the timepoint has been initialized and the values are safe to use;
   * Returns blockTimestamp The timestamp of the timepoint;
   * Returns tickCumulative the tick multiplied by seconds elapsed for the life of the pool as of the timepoint timestamp;
   * Returns secondsPerLiquidityCumulative the seconds per in range liquidity for the life of the pool as of the timepoint timestamp;
   * Returns volatilityCumulative Cumulative standard deviation for the life of the pool as of the timepoint timestamp;
   * Returns averageTick Time-weighted average tick;
   * Returns volumePerLiquidityCumulative Cumulative swap volume per liquidity for the life of the pool as of the timepoint timestamp;
   */
  function timepoints(uint256 index)
    external
    view
    returns (
      bool initialized,
      uint32 blockTimestamp,
      int56 tickCumulative,
      uint160 secondsPerLiquidityCumulative,
      uint88 volatilityCumulative,
      int24 averageTick,
      uint144 volumePerLiquidityCumulative
    );

  /**
   * @notice Returns the information about active incentive
   * @dev if there is no active incentive at the moment, virtualPool,endTimestamp,startTimestamp would be equal to 0
   * @return virtualPool The address of a virtual pool associated with the current active incentive
   */
  function activeIncentive() external view returns (address virtualPool);

  /**
   * @notice Returns the lock time for added liquidity
   */
  function liquidityCooldown() external view returns (uint32 cooldownInSeconds);

  /**
   * @notice The pool tick spacing
   * @dev Ticks can only be used at multiples of this value
   * e.g.: a tickSpacing of 60 means ticks can be initialized every 60th tick, i.e., ..., -120, -60, 0, 60, 120, ...
   * This value is an int24 to avoid casting even though it is always positive.
   * @return The tick spacing
   */
  function tickSpacing() external view returns (int24);
}

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

import '../libraries/AdaptiveFee.sol';

interface IDataStorageOperator {
  event FeeConfiguration(bool zto, AdaptiveFee.Configuration feeConfig);

  /**
   * @notice Returns data belonging to a certain timepoint
   * @param index The index of timepoint in the array
   * @dev There is more convenient function to fetch a timepoint: getTimepoints(). Which requires not an index but seconds
   * @return initialized Whether the timepoint has been initialized and the values are safe to use,
   * blockTimestamp The timestamp of the observation,
   * tickCumulative The tick multiplied by seconds elapsed for the life of the pool as of the timepoint timestamp,
   * secondsPerLiquidityCumulative The seconds per in range liquidity for the life of the pool as of the timepoint timestamp,
   * volatilityCumulative Cumulative standard deviation for the life of the pool as of the timepoint timestamp,
   * averageTick Time-weighted average tick,
   * volumePerLiquidityCumulative Cumulative swap volume per liquidity for the life of the pool as of the timepoint timestamp
   */
  function timepoints(uint256 index)
    external
    view
    returns (
      bool initialized,
      uint32 blockTimestamp,
      int56 tickCumulative,
      uint160 secondsPerLiquidityCumulative,
      uint88 volatilityCumulative,
      int24 averageTick,
      uint144 volumePerLiquidityCumulative
    );

  /// @notice Initialize the dataStorage array by writing the first slot. Called once for the lifecycle of the timepoints array
  /// @param time The time of the dataStorage initialization, via block.timestamp truncated to uint32
  /// @param tick Initial tick
  function initialize(uint32 time, int24 tick) external;

  /// @dev Reverts if an timepoint at or before the desired timepoint timestamp does not exist.
  /// 0 may be passed as `secondsAgo' to return the current cumulative values.
  /// If called with a timestamp falling between two timepoints, returns the counterfactual accumulator values
  /// at exactly the timestamp between the two timepoints.
  /// @param time The current block timestamp
  /// @param secondsAgo The amount of time to look back, in seconds, at which point to return an timepoint
  /// @param tick The current tick
  /// @param index The index of the timepoint that was most recently written to the timepoints array
  /// @param liquidity The current in-range pool liquidity
  /// @return tickCumulative The cumulative tick since the pool was first initialized, as of `secondsAgo`
  /// @return secondsPerLiquidityCumulative The cumulative seconds / max(1, liquidity) since the pool was first initialized, as of `secondsAgo`
  /// @return volatilityCumulative The cumulative volatility value since the pool was first initialized, as of `secondsAgo`
  /// @return volumePerAvgLiquidity The cumulative volume per liquidity value since the pool was first initialized, as of `secondsAgo`
  function getSingleTimepoint(
    uint32 time,
    uint32 secondsAgo,
    int24 tick,
    uint16 index,
    uint128 liquidity
  )
    external
    view
    returns (
      int56 tickCumulative,
      uint160 secondsPerLiquidityCumulative,
      uint112 volatilityCumulative,
      uint256 volumePerAvgLiquidity
    );

  /// @notice Returns the accumulator values as of each time seconds ago from the given time in the array of `secondsAgos`
  /// @dev Reverts if `secondsAgos` > oldest timepoint
  /// @param time The current block.timestamp
  /// @param secondsAgos Each amount of time to look back, in seconds, at which point to return an timepoint
  /// @param tick The current tick
  /// @param index The index of the timepoint that was most recently written to the timepoints array
  /// @param liquidity The current in-range pool liquidity
  /// @return tickCumulatives The cumulative tick since the pool was first initialized, as of each `secondsAgo`
  /// @return secondsPerLiquidityCumulatives The cumulative seconds / max(1, liquidity) since the pool was first initialized, as of each `secondsAgo`
  /// @return volatilityCumulatives The cumulative volatility values since the pool was first initialized, as of each `secondsAgo`
  /// @return volumePerAvgLiquiditys The cumulative volume per liquidity values since the pool was first initialized, as of each `secondsAgo`
  function getTimepoints(
    uint32 time,
    uint32[] memory secondsAgos,
    int24 tick,
    uint16 index,
    uint128 liquidity
  )
    external
    view
    returns (
      int56[] memory tickCumulatives,
      uint160[] memory secondsPerLiquidityCumulatives,
      uint112[] memory volatilityCumulatives,
      uint256[] memory volumePerAvgLiquiditys
    );

  /// @notice Returns average volatility in the range from time-WINDOW to time
  /// @param time The current block.timestamp
  /// @param tick The current tick
  /// @param index The index of the timepoint that was most recently written to the timepoints array
  /// @param liquidity The current in-range pool liquidity
  /// @return TWVolatilityAverage The average volatility in the recent range
  /// @return TWVolumePerLiqAverage The average volume per liquidity in the recent range
  function getAverages(
    uint32 time,
    int24 tick,
    uint16 index,
    uint128 liquidity
  ) external view returns (uint112 TWVolatilityAverage, uint256 TWVolumePerLiqAverage);

  /// @notice Writes an dataStorage timepoint to the array
  /// @dev Writable at most once per block. Index represents the most recently written element. index must be tracked externally.
  /// @param index The index of the timepoint that was most recently written to the timepoints array
  /// @param blockTimestamp The timestamp of the new timepoint
  /// @param tick The active tick at the time of the new timepoint
  /// @param liquidity The total in-range liquidity at the time of the new timepoint
  /// @param volumePerLiquidity The gmean(volumes)/liquidity at the time of the new timepoint
  /// @return indexUpdated The new index of the most recently written element in the dataStorage array
  function write(
    uint16 index,
    uint32 blockTimestamp,
    int24 tick,
    uint128 liquidity,
    uint128 volumePerLiquidity
  ) external returns (uint16 indexUpdated);

  /// @notice Changes fee configuration for the pool
  function changeFeeConfiguration(bool zto, AdaptiveFee.Configuration calldata feeConfig) external;

  /// @notice Calculates gmean(volume/liquidity) for block
  /// @param liquidity The current in-range pool liquidity
  /// @param amount0 Total amount of swapped token0
  /// @param amount1 Total amount of swapped token1
  /// @return volumePerLiquidity gmean(volume/liquidity) capped by 100000 << 64
  function calculateVolumePerLiquidity(
    uint128 liquidity,
    int256 amount0,
    int256 amount1
  ) external pure returns (uint128 volumePerLiquidity);

  /// @return windowLength Length of window used to calculate averages
  function window() external view returns (uint32 windowLength);

  /// @notice Calculates fee based on combination of sigmoids
  /// @param time The current block.timestamp
  /// @param tick The current tick
  /// @param index The index of the timepoint that was most recently written to the timepoints array
  /// @param liquidity The current in-range pool liquidity
  /// @return feeZto The fee for ZtO swaps in hundredths of a bip, i.e. 1e-6
  /// @return feeOtz The fee for OtZ swaps in hundredths of a bip, i.e. 1e-6
  function getFees(
    uint32 time,
    int24 tick,
    uint16 index,
    uint128 liquidity
  ) external view returns (uint16 feeZto, uint16 feeOtz);
}

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

/// @title Interface for verifying contract-based account signatures
/// @notice Interface that verifies provided signature for the data
/// @dev Interface defined by EIP-1271
interface IERC1271 {
    /// @notice Returns whether the provided signature is valid for the provided data
    /// @dev MUST return the bytes4 magic value 0x1626ba7e when function passes.
    /// MUST NOT modify state (using STATICCALL for solc < 0.5, view modifier for solc > 0.5).
    /// MUST allow external calls.
    /// @param hash Hash of the data to be signed
    /// @param signature Signature byte array associated with _data
    /// @return magicValue The bytes4 magic value 0x1626ba7e
    function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
}

// 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: 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: 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 >=0.5.0;

/// @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: 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: 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: 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 '@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 separator 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: MIT

pragma solidity ^0.7.0;

/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
interface IERC721Receiver {
    /**
     * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
     * by `operator` from `from`, this function is called.
     *
     * It must return its Solidity selector to confirm the token transfer.
     * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
     *
     * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
     */
    function onERC721Received(address operator, address from, uint256 tokenId, bytes calldata data) external returns (bytes4);
}

// 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: 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 Algebra positions in a non-fungible token interface which allows for them to be transferred
/// and authorized.
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
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 actualLiquidity the actual liquidity that was added into a pool. Could differ from
    /// _liquidity_ when using FeeOnTransfer tokens
    /// @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,
        uint128 actualLiquidity,
        uint256 amount0,
        uint256 amount1,
        address pool
    );
    /// @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 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,
            int24 tickLower,
            int24 tickUpper,
            uint128 liquidity,
            uint256 feeGrowthInside0LastX128,
            uint256 feeGrowthInside1LastX128,
            uint128 tokensOwed0,
            uint128 tokensOwed1
        );

    struct MintParams {
        address token0;
        address token1;
        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 achieve resulting liquidity
    /// @return amount1 The amount of token1 to achieve 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 >=0.5.0;

import './INonfungiblePositionManager.sol';

/// @title Describes position NFT tokens via URI
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
interface INonfungibleTokenPositionDescriptor {
    /// @notice Produces the URI describing a particular token ID for a position manager
    /// @dev Note this URI may be a data: URI with the JSON contents directly inlined
    /// @param positionManager The position manager for which to describe the token
    /// @param tokenId The ID of the token for which to produce a description, which may not be valid
    /// @return The URI of the ERC721-compliant metadata
    function tokenURI(INonfungiblePositionManager positionManager, uint256 tokenId)
        external
        view
        returns (string memory);
}

// 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
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
interface IPeripheryImmutableState {
    /// @return Returns the address of the Algebra factory
    function factory() external view returns (address);

    /// @return Returns the address of the pool Deployer
    function poolDeployer() external view returns (address);

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

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

/// @title Periphery Payments
/// @notice Functions to ease deposits and withdrawals of NativeToken
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
interface IPeripheryPayments {
    /// @notice Unwraps the contract's WNativeToken balance and sends it to recipient as NativeToken.
    /// @dev The amountMinimum parameter prevents malicious contracts from stealing WNativeToken from users.
    /// @param amountMinimum The minimum amount of WNativeToken to unwrap
    /// @param recipient The address receiving NativeToken
    function unwrapWNativeToken(uint256 amountMinimum, address recipient) external payable;

    /// @notice Refunds any NativeToken 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 refundNativeToken() 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.
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
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 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,
        uint160 sqrtPriceX96
    ) external payable returns (address pool);
}

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

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

/// @title Interface for WNativeToken
interface IWNativeToken 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: GPL-2.0-or-later
pragma solidity >=0.5.0;

import '@cryptoalgebra/core/contracts/libraries/FullMath.sol';
import '@cryptoalgebra/core/contracts/libraries/Constants.sol';

/// @title Liquidity amount functions
/// @notice Provides functions for computing liquidity amounts from token amounts and prices
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
library LiquidityAmounts {
    /// @notice Downcasts uint256 to uint128
    /// @param x The uint258 to be downcasted
    /// @return y The passed value, downcasted to uint128
    function toUint128(uint256 x) private pure returns (uint128 y) {
        require((y = uint128(x)) == x);
    }

    /// @notice Computes the amount of liquidity received for a given amount of token0 and price range
    /// @dev Calculates amount0 * (sqrt(upper) * sqrt(lower)) / (sqrt(upper) - sqrt(lower))
    /// @param sqrtRatioAX96 A sqrt price representing the first tick boundary
    /// @param sqrtRatioBX96 A sqrt price representing the second tick boundary
    /// @param amount0 The amount0 being sent in
    /// @return liquidity The amount of returned liquidity
    function getLiquidityForAmount0(
        uint160 sqrtRatioAX96,
        uint160 sqrtRatioBX96,
        uint256 amount0
    ) internal pure returns (uint128 liquidity) {
        if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);
        uint256 intermediate = FullMath.mulDiv(sqrtRatioAX96, sqrtRatioBX96, Constants.Q96);
        return toUint128(FullMath.mulDiv(amount0, intermediate, sqrtRatioBX96 - sqrtRatioAX96));
    }

    /// @notice Computes the amount of liquidity received for a given amount of token1 and price range
    /// @dev Calculates amount1 / (sqrt(upper) - sqrt(lower)).
    /// @param sqrtRatioAX96 A sqrt price representing the first tick boundary
    /// @param sqrtRatioBX96 A sqrt price representing the second tick boundary
    /// @param amount1 The amount1 being sent in
    /// @return liquidity The amount of returned liquidity
    function getLiquidityForAmount1(
        uint160 sqrtRatioAX96,
        uint160 sqrtRatioBX96,
        uint256 amount1
    ) internal pure returns (uint128 liquidity) {
        if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);
        return toUint128(FullMath.mulDiv(amount1, Constants.Q96, sqrtRatioBX96 - sqrtRatioAX96));
    }

    /// @notice Computes the maximum amount of liquidity received for a given amount of token0, token1, the current
    /// pool prices and the prices at the tick boundaries
    /// @param sqrtRatioX96 A sqrt price representing the current pool prices
    /// @param sqrtRatioAX96 A sqrt price representing the first tick boundary
    /// @param sqrtRatioBX96 A sqrt price representing the second tick boundary
    /// @param amount0 The amount of token0 being sent in
    /// @param amount1 The amount of token1 being sent in
    /// @return liquidity The maximum amount of liquidity received
    function getLiquidityForAmounts(
        uint160 sqrtRatioX96,
        uint160 sqrtRatioAX96,
        uint160 sqrtRatioBX96,
        uint256 amount0,
        uint256 amount1
    ) internal pure returns (uint128 liquidity) {
        if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);

        if (sqrtRatioX96 <= sqrtRatioAX96) {
            liquidity = getLiquidityForAmount0(sqrtRatioAX96, sqrtRatioBX96, amount0);
        } else if (sqrtRatioX96 < sqrtRatioBX96) {
            uint128 liquidity0 = getLiquidityForAmount0(sqrtRatioX96, sqrtRatioBX96, amount0);
            uint128 liquidity1 = getLiquidityForAmount1(sqrtRatioAX96, sqrtRatioX96, amount1);

            liquidity = liquidity0 < liquidity1 ? liquidity0 : liquidity1;
        } else {
            liquidity = getLiquidityForAmount1(sqrtRatioAX96, sqrtRatioBX96, amount1);
        }
    }

    /// @notice Computes the amount of token0 for a given amount of liquidity and a price range
    /// @param sqrtRatioAX96 A sqrt price representing the first tick boundary
    /// @param sqrtRatioBX96 A sqrt price representing the second tick boundary
    /// @param liquidity The liquidity being valued
    /// @return amount0 The amount of token0
    function getAmount0ForLiquidity(
        uint160 sqrtRatioAX96,
        uint160 sqrtRatioBX96,
        uint128 liquidity
    ) internal pure returns (uint256 amount0) {
        if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);

        return
            FullMath.mulDiv(uint256(liquidity) << Constants.RESOLUTION, sqrtRatioBX96 - sqrtRatioAX96, sqrtRatioBX96) /
            sqrtRatioAX96;
    }

    /// @notice Computes the amount of token1 for a given amount of liquidity and a price range
    /// @param sqrtRatioAX96 A sqrt price representing the first tick boundary
    /// @param sqrtRatioBX96 A sqrt price representing the second tick boundary
    /// @param liquidity The liquidity being valued
    /// @return amount1 The amount of token1
    function getAmount1ForLiquidity(
        uint160 sqrtRatioAX96,
        uint160 sqrtRatioBX96,
        uint128 liquidity
    ) internal pure returns (uint256 amount1) {
        if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);

        return FullMath.mulDiv(liquidity, sqrtRatioBX96 - sqrtRatioAX96, Constants.Q96);
    }

    /// @notice Computes the token0 and token1 value for a given amount of liquidity, the current
    /// pool prices and the prices at the tick boundaries
    /// @param sqrtRatioX96 A sqrt price representing the current pool prices
    /// @param sqrtRatioAX96 A sqrt price representing the first tick boundary
    /// @param sqrtRatioBX96 A sqrt price representing the second tick boundary
    /// @param liquidity The liquidity being valued
    /// @return amount0 The amount of token0
    /// @return amount1 The amount of token1
    function getAmountsForLiquidity(
        uint160 sqrtRatioX96,
        uint160 sqrtRatioAX96,
        uint160 sqrtRatioBX96,
        uint128 liquidity
    ) internal pure returns (uint256 amount0, uint256 amount1) {
        if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);

        if (sqrtRatioX96 <= sqrtRatioAX96) {
            amount0 = getAmount0ForLiquidity(sqrtRatioAX96, sqrtRatioBX96, liquidity);
        } else if (sqrtRatioX96 < sqrtRatioBX96) {
            amount0 = getAmount0ForLiquidity(sqrtRatioX96, sqrtRatioBX96, liquidity);
            amount1 = getAmount1ForLiquidity(sqrtRatioAX96, sqrtRatioX96, liquidity);
        } else {
            amount1 = getAmount1ForLiquidity(sqrtRatioAX96, sqrtRatioBX96, liquidity);
        }
    }
}

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

import '@cryptoalgebra/core/contracts/interfaces/IAlgebraFactory.sol';
import '@cryptoalgebra/core/contracts/interfaces/callback/IAlgebraMintCallback.sol';
import '@cryptoalgebra/core/contracts/libraries/TickMath.sol';

import '../libraries/PoolAddress.sol';
import '../libraries/CallbackValidation.sol';
import '../libraries/LiquidityAmounts.sol';

import './PeripheryPayments.sol';
import './PeripheryImmutableState.sol';

/// @title Liquidity management functions
/// @notice Internal functions for safely managing liquidity in Algebra
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
abstract contract LiquidityManagement is IAlgebraMintCallback, PeripheryImmutableState, PeripheryPayments {
    struct MintCallbackData {
        PoolAddress.PoolKey poolKey;
        address payer;
    }

    /// @inheritdoc IAlgebraMintCallback
    function algebraMintCallback(
        uint256 amount0Owed,
        uint256 amount1Owed,
        bytes calldata data
    ) external override {
        MintCallbackData memory decoded = abi.decode(data, (MintCallbackData));
        CallbackValidation.verifyCallback(poolDeployer, decoded.poolKey);

        if (amount0Owed > 0) pay(decoded.poolKey.token0, decoded.payer, msg.sender, amount0Owed);
        if (amount1Owed > 0) pay(decoded.poolKey.token1, decoded.payer, msg.sender, amount1Owed);
    }

    struct AddLiquidityParams {
        address token0;
        address token1;
        address recipient;
        int24 tickLower;
        int24 tickUpper;
        uint256 amount0Desired;
        uint256 amount1Desired;
        uint256 amount0Min;
        uint256 amount1Min;
    }

    /// @notice Add liquidity to an initialized pool
    function addLiquidity(AddLiquidityParams memory params)
        internal
        returns (
            uint128 liquidity,
            uint256 actualLiquidity,
            uint256 amount0,
            uint256 amount1,
            IAlgebraPool pool
        )
    {
        PoolAddress.PoolKey memory poolKey = PoolAddress.PoolKey({token0: params.token0, token1: params.token1});

        pool = IAlgebraPool(PoolAddress.computeAddress(poolDeployer, poolKey));

        // compute the liquidity amount
        {
            (uint160 sqrtPriceX96, , , , , , , ) = pool.globalState();
            uint160 sqrtRatioAX96 = TickMath.getSqrtRatioAtTick(params.tickLower);
            uint160 sqrtRatioBX96 = TickMath.getSqrtRatioAtTick(params.tickUpper);

            liquidity = LiquidityAmounts.getLiquidityForAmounts(
                sqrtPriceX96,
                sqrtRatioAX96,
                sqrtRatioBX96,
                params.amount0Desired,
                params.amount1Desired
            );
        }

        (amount0, amount1, actualLiquidity) = pool.mint(
            msg.sender,
            params.recipient,
            params.tickLower,
            params.tickUpper,
            liquidity,
            abi.encode(MintCallbackData({poolKey: poolKey, payer: msg.sender}))
        );

        require(amount0 >= params.amount0Min && amount1 >= params.amount1Min, 'Price slippage check');
    }
}

// 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) external 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;
pragma abicoder v2;

import '@cryptoalgebra/core/contracts/interfaces/IAlgebraPool.sol';
import '@cryptoalgebra/core/contracts/libraries/Constants.sol';
import '@cryptoalgebra/core/contracts/libraries/FullMath.sol';

import './interfaces/INonfungiblePositionManager.sol';
import './interfaces/INonfungibleTokenPositionDescriptor.sol';
import './libraries/PositionKey.sol';
import './libraries/PoolAddress.sol';
import './base/LiquidityManagement.sol';
import './base/PeripheryImmutableState.sol';
import './base/Multicall.sol';
import './base/ERC721Permit.sol';
import './base/PeripheryValidation.sol';
import './base/SelfPermit.sol';
import './base/PoolInitializer.sol';

/// @title NFT positions
/// @notice Wraps Algebra  positions in the ERC721 non-fungible token interface
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
contract NonfungiblePositionManager is
    INonfungiblePositionManager,
    Multicall,
    ERC721Permit,
    PeripheryImmutableState,
    PoolInitializer,
    LiquidityManagement,
    PeripheryValidation,
    SelfPermit
{
    // details about the Algebra position
    struct Position {
        uint96 nonce; // the nonce for permits
        address operator; // the address that is approved for spending this token
        uint80 poolId; // the ID of the pool with which this token is connected
        int24 tickLower; // the tick range of the position
        int24 tickUpper;
        uint128 liquidity; // the liquidity of the position
        uint256 feeGrowthInside0LastX128; // the fee growth of the aggregate position as of the last action on the individual position
        uint256 feeGrowthInside1LastX128;
        uint128 tokensOwed0; // how many uncollected tokens are owed to the position, as of the last computation
        uint128 tokensOwed1;
    }

    /// @dev IDs of pools assigned by this contract
    mapping(address => uint80) private _poolIds;

    /// @dev Pool keys by pool ID, to save on SSTOREs for position data
    mapping(uint80 => PoolAddress.PoolKey) private _poolIdToPoolKey;

    /// @dev The token ID position data
    mapping(uint256 => Position) private _positions;

    /// @dev The ID of the next token that will be minted. Skips 0
    uint176 private _nextId = 1;
    /// @dev The ID of the next pool that is used for the first time. Skips 0
    uint80 private _nextPoolId = 1;

    /// @dev The address of the token descriptor contract, which handles generating token URIs for position tokens
    address private immutable _tokenDescriptor;

    constructor(
        address _factory,
        address _WNativeToken,
        address _tokenDescriptor_,
        address _poolDeployer
    )
        ERC721Permit('Algebra Positions NFT-V1', 'ALGB-POS', '1')
        PeripheryImmutableState(_factory, _WNativeToken, _poolDeployer)
    {
        _tokenDescriptor = _tokenDescriptor_;
    }

    /// @inheritdoc INonfungiblePositionManager
    function positions(uint256 tokenId)
        external
        view
        override
        returns (
            uint96 nonce,
            address operator,
            address token0,
            address token1,
            int24 tickLower,
            int24 tickUpper,
            uint128 liquidity,
            uint256 feeGrowthInside0LastX128,
            uint256 feeGrowthInside1LastX128,
            uint128 tokensOwed0,
            uint128 tokensOwed1
        )
    {
        Position memory position = _positions[tokenId];
        require(position.poolId != 0, 'Invalid token ID');
        PoolAddress.PoolKey memory poolKey = _poolIdToPoolKey[position.poolId];
        return (
            position.nonce,
            position.operator,
            poolKey.token0,
            poolKey.token1,
            position.tickLower,
            position.tickUpper,
            position.liquidity,
            position.feeGrowthInside0LastX128,
            position.feeGrowthInside1LastX128,
            position.tokensOwed0,
            position.tokensOwed1
        );
    }

    /// @dev Caches a pool key
    function cachePoolKey(address pool, PoolAddress.PoolKey memory poolKey) private returns (uint80 poolId) {
        poolId = _poolIds[pool];
        if (poolId == 0) {
            _poolIds[pool] = (poolId = _nextPoolId++);
            _poolIdToPoolKey[poolId] = poolKey;
        }
    }

    /// @inheritdoc INonfungiblePositionManager
    function mint(MintParams calldata params)
        external
        payable
        override
        checkDeadline(params.deadline)
        returns (
            uint256 tokenId,
            uint128 liquidity,
            uint256 amount0,
            uint256 amount1
        )
    {
        IAlgebraPool pool;
        uint256 actualLiquidity;
        (liquidity, actualLiquidity, amount0, amount1, pool) = addLiquidity(
            AddLiquidityParams({
                token0: params.token0,
                token1: params.token1,
                recipient: address(this),
                tickLower: params.tickLower,
                tickUpper: params.tickUpper,
                amount0Desired: params.amount0Desired,
                amount1Desired: params.amount1Desired,
                amount0Min: params.amount0Min,
                amount1Min: params.amount1Min
            })
        );

        _mint(params.recipient, (tokenId = _nextId++));

        bytes32 positionKey = PositionKey.compute(address(this), params.tickLower, params.tickUpper);
        (, , uint256 feeGrowthInside0LastX128, uint256 feeGrowthInside1LastX128, , ) = pool.positions(positionKey);

        // idempotent set
        uint80 poolId = cachePoolKey(
            address(pool),
            PoolAddress.PoolKey({token0: params.token0, token1: params.token1})
        );

        _positions[tokenId] = Position({
            nonce: 0,
            operator: address(0),
            poolId: poolId,
            tickLower: params.tickLower,
            tickUpper: params.tickUpper,
            liquidity: uint128(actualLiquidity),
            feeGrowthInside0LastX128: feeGrowthInside0LastX128,
            feeGrowthInside1LastX128: feeGrowthInside1LastX128,
            tokensOwed0: 0,
            tokensOwed1: 0
        });

        emit IncreaseLiquidity(tokenId, liquidity, uint128(actualLiquidity), amount0, amount1, address(pool));
    }

    modifier isAuthorizedForToken(uint256 tokenId) {
        require(_isApprovedOrOwner(msg.sender, tokenId), 'Not approved');
        _;
    }

    function tokenURI(uint256 tokenId) public view override(ERC721, IERC721Metadata) returns (string memory) {
        require(_exists(tokenId));
        return INonfungibleTokenPositionDescriptor(_tokenDescriptor).tokenURI(this, tokenId);
    }

    // save bytecode by removing implementation of unused method
    function baseURI() public pure override returns (string memory) {}

    /// @inheritdoc INonfungiblePositionManager
    function increaseLiquidity(IncreaseLiquidityParams calldata params)
        external
        payable
        override
        checkDeadline(params.deadline)
        returns (
            uint128 liquidity,
            uint256 amount0,
            uint256 amount1
        )
    {
        Position storage position = _positions[params.tokenId];

        PoolAddress.PoolKey memory poolKey = _poolIdToPoolKey[position.poolId];

        IAlgebraPool pool;
        uint256 actualLiquidity;
        (liquidity, actualLiquidity, amount0, amount1, pool) = addLiquidity(
            AddLiquidityParams({
                token0: poolKey.token0,
                token1: poolKey.token1,
                tickLower: position.tickLower,
                tickUpper: position.tickUpper,
                amount0Desired: params.amount0Desired,
                amount1Desired: params.amount1Desired,
                amount0Min: params.amount0Min,
                amount1Min: params.amount1Min,
                recipient: address(this)
            })
        );

        bytes32 positionKey = PositionKey.compute(address(this), position.tickLower, position.tickUpper);

        // this is now updated to the current transaction
        (, , uint256 feeGrowthInside0LastX128, uint256 feeGrowthInside1LastX128, , ) = pool.positions(positionKey);

        position.tokensOwed0 += uint128(
            FullMath.mulDiv(
                feeGrowthInside0LastX128 - position.feeGrowthInside0LastX128,
                position.liquidity,
                Constants.Q128
            )
        );
        position.tokensOwed1 += uint128(
            FullMath.mulDiv(
                feeGrowthInside1LastX128 - position.feeGrowthInside1LastX128,
                position.liquidity,
                Constants.Q128
            )
        );

        position.feeGrowthInside0LastX128 = feeGrowthInside0LastX128;
        position.feeGrowthInside1LastX128 = feeGrowthInside1LastX128;
        position.liquidity += uint128(actualLiquidity);

        emit IncreaseLiquidity(params.tokenId, liquidity, uint128(actualLiquidity), amount0, amount1, address(pool));
    }

    /// @inheritdoc INonfungiblePositionManager
    function decreaseLiquidity(DecreaseLiquidityParams calldata params)
        external
        payable
        override
        isAuthorizedForToken(params.tokenId)
        checkDeadline(params.deadline)
        returns (uint256 amount0, uint256 amount1)
    {
        require(params.liquidity > 0);
        Position storage position = _positions[params.tokenId];

        uint128 positionLiquidity = position.liquidity;
        require(positionLiquidity >= params.liquidity);

        PoolAddress.PoolKey memory poolKey = _poolIdToPoolKey[position.poolId];
        IAlgebraPool pool = IAlgebraPool(PoolAddress.computeAddress(poolDeployer, poolKey));
        (amount0, amount1) = pool.burn(position.tickLower, position.tickUpper, params.liquidity);

        require(amount0 >= params.amount0Min && amount1 >= params.amount1Min, 'Price slippage check');

        bytes32 positionKey = PositionKey.compute(address(this), position.tickLower, position.tickUpper);
        // this is now updated to the current transaction
        (, , uint256 feeGrowthInside0LastX128, uint256 feeGrowthInside1LastX128, , ) = pool.positions(positionKey);

        position.tokensOwed0 +=
            uint128(amount0) +
            uint128(
                FullMath.mulDiv(
                    feeGrowthInside0LastX128 - position.feeGrowthInside0LastX128,
                    positionLiquidity,
                    Constants.Q128
                )
            );
        position.tokensOwed1 +=
            uint128(amount1) +
            uint128(
                FullMath.mulDiv(
                    feeGrowthInside1LastX128 - position.feeGrowthInside1LastX128,
                    positionLiquidity,
                    Constants.Q128
                )
            );

        position.feeGrowthInside0LastX128 = feeGrowthInside0LastX128;
        position.feeGrowthInside1LastX128 = feeGrowthInside1LastX128;
        // subtraction is safe because we checked positionLiquidity is gte params.liquidity
        position.liquidity = positionLiquidity - params.liquidity;

        emit DecreaseLiquidity(params.tokenId, params.liquidity, amount0, amount1);
    }

    /// @inheritdoc INonfungiblePositionManager
    function collect(CollectParams calldata params)
        external
        payable
        override
        isAuthorizedForToken(params.tokenId)
        returns (uint256 amount0, uint256 amount1)
    {
        require(params.amount0Max > 0 || params.amount1Max > 0);
        // allow collecting to the nft position manager address with address 0
        address recipient = params.recipient == address(0) ? address(this) : params.recipient;

        Position storage position = _positions[params.tokenId];

        PoolAddress.PoolKey memory poolKey = _poolIdToPoolKey[position.poolId];

        IAlgebraPool pool = IAlgebraPool(PoolAddress.computeAddress(poolDeployer, poolKey));

        (uint128 tokensOwed0, uint128 tokensOwed1) = (position.tokensOwed0, position.tokensOwed1);

        // trigger an update of the position fees owed and fee growth snapshots if it has any liquidity
        if (position.liquidity > 0) {
            pool.burn(position.tickLower, position.tickUpper, 0);
            (, , uint256 feeGrowthInside0LastX128, uint256 feeGrowthInside1LastX128, , ) = pool.positions(
                PositionKey.compute(address(this), position.tickLower, position.tickUpper)
            );

            tokensOwed0 += uint128(
                FullMath.mulDiv(
                    feeGrowthInside0LastX128 - position.feeGrowthInside0LastX128,
                    position.liquidity,
                    Constants.Q128
                )
            );
            tokensOwed1 += uint128(
                FullMath.mulDiv(
                    feeGrowthInside1LastX128 - position.feeGrowthInside1LastX128,
                    position.liquidity,
                    Constants.Q128
                )
            );

            position.feeGrowthInside0LastX128 = feeGrowthInside0LastX128;
            position.feeGrowthInside1LastX128 = feeGrowthInside1LastX128;
        }

        // compute the arguments to give to the pool#collect method
        (uint128 amount0Collect, uint128 amount1Collect) = (
            params.amount0Max > tokensOwed0 ? tokensOwed0 : params.amount0Max,
            params.amount1Max > tokensOwed1 ? tokensOwed1 : params.amount1Max
        );

        // the actual amounts collected are returned
        (amount0, amount1) = pool.collect(
            recipient,
            position.tickLower,
            position.tickUpper,
            amount0Collect,
            amount1Collect
        );

        // sometimes there will be a few less wei than expected due to rounding down in core, but we just subtract the full amount expected
        // instead of the actual amount so we can burn the token
        (position.tokensOwed0, position.tokensOwed1) = (tokensOwed0 - amount0Collect, tokensOwed1 - amount1Collect);

        emit Collect(params.tokenId, recipient, amount0Collect, amount1Collect);
    }

    /// @inheritdoc INonfungiblePositionManager
    function burn(uint256 tokenId) external payable override isAuthorizedForToken(tokenId) {
        Position storage position = _positions[tokenId];
        require(position.liquidity == 0 && position.tokensOwed0 == 0 && position.tokensOwed1 == 0, 'Not cleared');
        delete _positions[tokenId];
        _burn(tokenId);
    }

    function _getAndIncrementNonce(uint256 tokenId) internal override returns (uint256) {
        return uint256(_positions[tokenId].nonce++);
    }

    /// @inheritdoc IERC721
    function getApproved(uint256 tokenId) public view override(ERC721, IERC721) returns (address) {
        require(_exists(tokenId), 'ERC721: approved query for nonexistent token');

        return _positions[tokenId].operator;
    }

    /// @dev Overrides _approve to use the operator in the position, which is packed with the position permit nonce
    function _approve(address to, uint256 tokenId) internal override(ERC721) {
        _positions[tokenId].operator = to;
        emit Approval(ownerOf(tokenId), to, tokenId);
    }
}

// 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
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
abstract contract PeripheryImmutableState is IPeripheryImmutableState {
    /// @inheritdoc IPeripheryImmutableState
    address public immutable override factory;
    /// @inheritdoc IPeripheryImmutableState
    address public immutable override poolDeployer;
    /// @inheritdoc IPeripheryImmutableState
    address public immutable override WNativeToken;

    constructor(
        address _factory,
        address _WNativeToken,
        address _poolDeployer
    ) {
        factory = _factory;
        poolDeployer = _poolDeployer;
        WNativeToken = _WNativeToken;
    }
}

// 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/IWNativeToken.sol';

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

import './PeripheryImmutableState.sol';

/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
abstract contract PeripheryPayments is IPeripheryPayments, PeripheryImmutableState {
    receive() external payable {
        require(msg.sender == WNativeToken, 'Not WNativeToken');
    }

    /// @inheritdoc IPeripheryPayments
    function unwrapWNativeToken(uint256 amountMinimum, address recipient) external payable override {
        uint256 balanceWNativeToken = IWNativeToken(WNativeToken).balanceOf(address(this));
        require(balanceWNativeToken >= amountMinimum, 'Insufficient WNativeToken');

        if (balanceWNativeToken > 0) {
            IWNativeToken(WNativeToken).withdraw(balanceWNativeToken);
            TransferHelper.safeTransferNative(recipient, balanceWNativeToken);
        }
    }

    /// @inheritdoc IPeripheryPayments
    function sweepToken(
        address token,
        uint256 amountMinimum,
        address recipient
    ) external 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 refundNativeToken() external payable override {
        if (address(this).balance > 0) TransferHelper.safeTransferNative(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 == WNativeToken && address(this).balance >= value) {
            // pay with WNativeToken
            IWNativeToken(WNativeToken).deposit{value: value}(); // wrap only what is needed to pay
            IWNativeToken(WNativeToken).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 =0.7.6;

import './BlockTimestamp.sol';

/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
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 >=0.5.0;

/// @title Provides functions for deriving a pool address from the factory, tokens, and the fee
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
library PoolAddress {
    bytes32 internal constant POOL_INIT_CODE_HASH = 0x6c1bebd370ba84753516bc1393c0d0a6c645856da55f5393ac8ab3d6dbc861d3;

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

    /// @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
    /// @return Poolkey The pool details with ordered token0 and token1 assignments
    function getPoolKey(address tokenA, address tokenB) internal pure returns (PoolKey memory) {
        if (tokenA > tokenB) (tokenA, tokenB) = (tokenB, tokenA);
        return PoolKey({token0: tokenA, token1: tokenB});
    }

    /// @notice Deterministically computes the pool address given the factory and PoolKey
    /// @param factory The Algebra 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)),
                        POOL_INIT_CODE_HASH
                    )
                )
            )
        );
    }
}

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

import '@cryptoalgebra/core/contracts/interfaces/IAlgebraFactory.sol';
import '@cryptoalgebra/core/contracts/interfaces/IAlgebraPool.sol';
import './PeripheryImmutableState.sol';
import '../interfaces/IPoolInitializer.sol';

/// @title Creates and initializes Algebra Pools
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-periphery
abstract contract PoolInitializer is IPoolInitializer, PeripheryImmutableState {
    /// @inheritdoc IPoolInitializer
    function createAndInitializePoolIfNecessary(
        address token0,
        address token1,
        uint160 sqrtPriceX96
    ) external payable override returns (address pool) {
        require(token0 < token1);

        pool = IAlgebraFactory(factory).poolByPair(token0, token1);

        if (pool == address(0)) {
            pool = IAlgebraFactory(factory).createPool(token0, token1);

            IAlgebraPool(pool).initialize(sqrtPriceX96);
        } else {
            (uint160 sqrtPriceX96Existing, , , , , , , ) = IAlgebraPool(pool).globalState();
            if (sqrtPriceX96Existing == 0) {
                IAlgebraPool(pool).initialize(sqrtPriceX96);
            }
        }
    }
}

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

library PositionKey {
    /// @dev Returns the key of the position in the core library
    function compute(
        address owner,
        int24 bottomTick,
        int24 topTick
    ) internal pure returns (bytes32 key) {
        assembly {
            key := or(shl(24, or(shl(24, owner), and(bottomTick, 0xFFFFFF))), and(topTick, 0xFFFFFF))
        }
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}

// 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: MIT

pragma solidity ^0.7.0;

/**
 * @dev String operations.
 */
library Strings {
    /**
     * @dev Converts a `uint256` to its ASCII `string` representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        // Inspired by OraclizeAPI's implementation - MIT licence
        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol

        if (value == 0) {
            return "0";
        }
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) {
            digits++;
            temp /= 10;
        }
        bytes memory buffer = new bytes(digits);
        uint256 index = digits - 1;
        temp = value;
        while (temp != 0) {
            buffer[index--] = bytes1(uint8(48 + temp % 10));
            temp /= 10;
        }
        return string(buffer);
    }
}

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

/// @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
/// @dev Credit to Uniswap Labs under GPL-2.0-or-later license:
/// https://github.com/Uniswap/v3-core/blob/main/contracts/libraries
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 price 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 price) {
    // get abs value
    int24 mask = tick >> (24 - 1);
    uint256 absTick = uint256((tick ^ mask) - mask);
    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
    price = uint160((ratio >> 32) + (ratio % (1 << 32) == 0 ? 0 : 1));
  }

  /// @notice Calculates the greatest tick value such that getRatioAtTick(tick) <= ratio
  /// @dev Throws in case price < MIN_SQRT_RATIO, as MIN_SQRT_RATIO is the lowest value getRatioAtTick may
  /// ever return.
  /// @param price 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 price) internal pure returns (int24 tick) {
    // second inequality must be < because the price can never reach the price at the max tick
    require(price >= MIN_SQRT_RATIO && price < MAX_SQRT_RATIO, 'R');
    uint256 ratio = uint256(price) << 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) <= price ? tickHi : tickLow;
  }
}