Napier Pool LP Token

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @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
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 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://consensys.net/diligence/blog/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/v0.8.0/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");

        (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 functionCallWithValue(target, data, 0, "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");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, 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) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, 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) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // 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
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

import "./Errors.sol" as CastingErrors;
import { MAX_UINT128, MAX_UINT40 } from "../Common.sol";
import { uMAX_SD1x18, uMIN_SD1x18 } from "../sd1x18/Constants.sol";
import { SD1x18 } from "../sd1x18/ValueType.sol";
import { uMAX_UD2x18 } from "../ud2x18/Constants.sol";
import { UD2x18 } from "../ud2x18/ValueType.sol";
import { UD60x18 } from "../ud60x18/ValueType.sol";
import { SD59x18 } from "./ValueType.sol";

/// @notice Casts an SD59x18 number into int256.
/// @dev This is basically a functional alias for {unwrap}.
function intoInt256(SD59x18 x) pure returns (int256 result) {
    result = SD59x18.unwrap(x);
}

/// @notice Casts an SD59x18 number into SD1x18.
/// @dev Requirements:
/// - x must be greater than or equal to `uMIN_SD1x18`.
/// - x must be less than or equal to `uMAX_SD1x18`.
function intoSD1x18(SD59x18 x) pure returns (SD1x18 result) {
    int256 xInt = SD59x18.unwrap(x);
    if (xInt < uMIN_SD1x18) {
        revert CastingErrors.PRBMath_SD59x18_IntoSD1x18_Underflow(x);
    }
    if (xInt > uMAX_SD1x18) {
        revert CastingErrors.PRBMath_SD59x18_IntoSD1x18_Overflow(x);
    }
    result = SD1x18.wrap(int64(xInt));
}

/// @notice Casts an SD59x18 number into UD2x18.
/// @dev Requirements:
/// - x must be positive.
/// - x must be less than or equal to `uMAX_UD2x18`.
function intoUD2x18(SD59x18 x) pure returns (UD2x18 result) {
    int256 xInt = SD59x18.unwrap(x);
    if (xInt < 0) {
        revert CastingErrors.PRBMath_SD59x18_IntoUD2x18_Underflow(x);
    }
    if (xInt > int256(uint256(uMAX_UD2x18))) {
        revert CastingErrors.PRBMath_SD59x18_IntoUD2x18_Overflow(x);
    }
    result = UD2x18.wrap(uint64(uint256(xInt)));
}

/// @notice Casts an SD59x18 number into UD60x18.
/// @dev Requirements:
/// - x must be positive.
function intoUD60x18(SD59x18 x) pure returns (UD60x18 result) {
    int256 xInt = SD59x18.unwrap(x);
    if (xInt < 0) {
        revert CastingErrors.PRBMath_SD59x18_IntoUD60x18_Underflow(x);
    }
    result = UD60x18.wrap(uint256(xInt));
}

/// @notice Casts an SD59x18 number into uint256.
/// @dev Requirements:
/// - x must be positive.
function intoUint256(SD59x18 x) pure returns (uint256 result) {
    int256 xInt = SD59x18.unwrap(x);
    if (xInt < 0) {
        revert CastingErrors.PRBMath_SD59x18_IntoUint256_Underflow(x);
    }
    result = uint256(xInt);
}

/// @notice Casts an SD59x18 number into uint128.
/// @dev Requirements:
/// - x must be positive.
/// - x must be less than or equal to `uMAX_UINT128`.
function intoUint128(SD59x18 x) pure returns (uint128 result) {
    int256 xInt = SD59x18.unwrap(x);
    if (xInt < 0) {
        revert CastingErrors.PRBMath_SD59x18_IntoUint128_Underflow(x);
    }
    if (xInt > int256(uint256(MAX_UINT128))) {
        revert CastingErrors.PRBMath_SD59x18_IntoUint128_Overflow(x);
    }
    result = uint128(uint256(xInt));
}

/// @notice Casts an SD59x18 number into uint40.
/// @dev Requirements:
/// - x must be positive.
/// - x must be less than or equal to `MAX_UINT40`.
function intoUint40(SD59x18 x) pure returns (uint40 result) {
    int256 xInt = SD59x18.unwrap(x);
    if (xInt < 0) {
        revert CastingErrors.PRBMath_SD59x18_IntoUint40_Underflow(x);
    }
    if (xInt > int256(uint256(MAX_UINT40))) {
        revert CastingErrors.PRBMath_SD59x18_IntoUint40_Overflow(x);
    }
    result = uint40(uint256(xInt));
}

/// @notice Alias for {wrap}.
function sd(int256 x) pure returns (SD59x18 result) {
    result = SD59x18.wrap(x);
}

/// @notice Alias for {wrap}.
function sd59x18(int256 x) pure returns (SD59x18 result) {
    result = SD59x18.wrap(x);
}

/// @notice Unwraps an SD59x18 number into int256.
function unwrap(SD59x18 x) pure returns (int256 result) {
    result = SD59x18.unwrap(x);
}

/// @notice Wraps an int256 number into SD59x18.
function wrap(int256 x) pure returns (SD59x18 result) {
    result = SD59x18.wrap(x);
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

// Common.sol
//
// Common mathematical functions needed by both SD59x18 and UD60x18. Note that these global functions do not
// always operate with SD59x18 and UD60x18 numbers.

/*//////////////////////////////////////////////////////////////////////////
                                CUSTOM ERRORS
//////////////////////////////////////////////////////////////////////////*/

/// @notice Thrown when the resultant value in {mulDiv} overflows uint256.
error PRBMath_MulDiv_Overflow(uint256 x, uint256 y, uint256 denominator);

/// @notice Thrown when the resultant value in {mulDiv18} overflows uint256.
error PRBMath_MulDiv18_Overflow(uint256 x, uint256 y);

/// @notice Thrown when one of the inputs passed to {mulDivSigned} is `type(int256).min`.
error PRBMath_MulDivSigned_InputTooSmall();

/// @notice Thrown when the resultant value in {mulDivSigned} overflows int256.
error PRBMath_MulDivSigned_Overflow(int256 x, int256 y);

/*//////////////////////////////////////////////////////////////////////////
                                    CONSTANTS
//////////////////////////////////////////////////////////////////////////*/

/// @dev The maximum value a uint128 number can have.
uint128 constant MAX_UINT128 = type(uint128).max;

/// @dev The maximum value a uint40 number can have.
uint40 constant MAX_UINT40 = type(uint40).max;

/// @dev The unit number, which the decimal precision of the fixed-point types.
uint256 constant UNIT = 1e18;

/// @dev The unit number inverted mod 2^256.
uint256 constant UNIT_INVERSE = 78156646155174841979727994598816262306175212592076161876661_508869554232690281;

/// @dev The the largest power of two that divides the decimal value of `UNIT`. The logarithm of this value is the least significant
/// bit in the binary representation of `UNIT`.
uint256 constant UNIT_LPOTD = 262144;

/*//////////////////////////////////////////////////////////////////////////
                                    FUNCTIONS
//////////////////////////////////////////////////////////////////////////*/

/// @notice Calculates the binary exponent of x using the binary fraction method.
/// @dev Has to use 192.64-bit fixed-point numbers. See https://ethereum.stackexchange.com/a/96594/24693.
/// @param x The exponent as an unsigned 192.64-bit fixed-point number.
/// @return result The result as an unsigned 60.18-decimal fixed-point number.
/// @custom:smtchecker abstract-function-nondet
function exp2(uint256 x) pure returns (uint256 result) {
    unchecked {
        // Start from 0.5 in the 192.64-bit fixed-point format.
        result = 0x800000000000000000000000000000000000000000000000;

        // The following logic multiplies the result by $\sqrt{2^{-i}}$ when the bit at position i is 1. Key points:
        //
        // 1. Intermediate results will not overflow, as the starting point is 2^191 and all magic factors are under 2^65.
        // 2. The rationale for organizing the if statements into groups of 8 is gas savings. If the result of performing
        // a bitwise AND operation between x and any value in the array [0x80; 0x40; 0x20; 0x10; 0x08; 0x04; 0x02; 0x01] is 1,
        // we know that `x & 0xFF` is also 1.
        if (x & 0xFF00000000000000 > 0) {
            if (x & 0x8000000000000000 > 0) {
                result = (result * 0x16A09E667F3BCC909) >> 64;
            }
            if (x & 0x4000000000000000 > 0) {
                result = (result * 0x1306FE0A31B7152DF) >> 64;
            }
            if (x & 0x2000000000000000 > 0) {
                result = (result * 0x1172B83C7D517ADCE) >> 64;
            }
            if (x & 0x1000000000000000 > 0) {
                result = (result * 0x10B5586CF9890F62A) >> 64;
            }
            if (x & 0x800000000000000 > 0) {
                result = (result * 0x1059B0D31585743AE) >> 64;
            }
            if (x & 0x400000000000000 > 0) {
                result = (result * 0x102C9A3E778060EE7) >> 64;
            }
            if (x & 0x200000000000000 > 0) {
                result = (result * 0x10163DA9FB33356D8) >> 64;
            }
            if (x & 0x100000000000000 > 0) {
                result = (result * 0x100B1AFA5ABCBED61) >> 64;
            }
        }

        if (x & 0xFF000000000000 > 0) {
            if (x & 0x80000000000000 > 0) {
                result = (result * 0x10058C86DA1C09EA2) >> 64;
            }
            if (x & 0x40000000000000 > 0) {
                result = (result * 0x1002C605E2E8CEC50) >> 64;
            }
            if (x & 0x20000000000000 > 0) {
                result = (result * 0x100162F3904051FA1) >> 64;
            }
            if (x & 0x10000000000000 > 0) {
                result = (result * 0x1000B175EFFDC76BA) >> 64;
            }
            if (x & 0x8000000000000 > 0) {
                result = (result * 0x100058BA01FB9F96D) >> 64;
            }
            if (x & 0x4000000000000 > 0) {
                result = (result * 0x10002C5CC37DA9492) >> 64;
            }
            if (x & 0x2000000000000 > 0) {
                result = (result * 0x1000162E525EE0547) >> 64;
            }
            if (x & 0x1000000000000 > 0) {
                result = (result * 0x10000B17255775C04) >> 64;
            }
        }

        if (x & 0xFF0000000000 > 0) {
            if (x & 0x800000000000 > 0) {
                result = (result * 0x1000058B91B5BC9AE) >> 64;
            }
            if (x & 0x400000000000 > 0) {
                result = (result * 0x100002C5C89D5EC6D) >> 64;
            }
            if (x & 0x200000000000 > 0) {
                result = (result * 0x10000162E43F4F831) >> 64;
            }
            if (x & 0x100000000000 > 0) {
                result = (result * 0x100000B1721BCFC9A) >> 64;
            }
            if (x & 0x80000000000 > 0) {
                result = (result * 0x10000058B90CF1E6E) >> 64;
            }
            if (x & 0x40000000000 > 0) {
                result = (result * 0x1000002C5C863B73F) >> 64;
            }
            if (x & 0x20000000000 > 0) {
                result = (result * 0x100000162E430E5A2) >> 64;
            }
            if (x & 0x10000000000 > 0) {
                result = (result * 0x1000000B172183551) >> 64;
            }
        }

        if (x & 0xFF00000000 > 0) {
            if (x & 0x8000000000 > 0) {
                result = (result * 0x100000058B90C0B49) >> 64;
            }
            if (x & 0x4000000000 > 0) {
                result = (result * 0x10000002C5C8601CC) >> 64;
            }
            if (x & 0x2000000000 > 0) {
                result = (result * 0x1000000162E42FFF0) >> 64;
            }
            if (x & 0x1000000000 > 0) {
                result = (result * 0x10000000B17217FBB) >> 64;
            }
            if (x & 0x800000000 > 0) {
                result = (result * 0x1000000058B90BFCE) >> 64;
            }
            if (x & 0x400000000 > 0) {
                result = (result * 0x100000002C5C85FE3) >> 64;
            }
            if (x & 0x200000000 > 0) {
                result = (result * 0x10000000162E42FF1) >> 64;
            }
            if (x & 0x100000000 > 0) {
                result = (result * 0x100000000B17217F8) >> 64;
            }
        }

        if (x & 0xFF000000 > 0) {
            if (x & 0x80000000 > 0) {
                result = (result * 0x10000000058B90BFC) >> 64;
            }
            if (x & 0x40000000 > 0) {
                result = (result * 0x1000000002C5C85FE) >> 64;
            }
            if (x & 0x20000000 > 0) {
                result = (result * 0x100000000162E42FF) >> 64;
            }
            if (x & 0x10000000 > 0) {
                result = (result * 0x1000000000B17217F) >> 64;
            }
            if (x & 0x8000000 > 0) {
                result = (result * 0x100000000058B90C0) >> 64;
            }
            if (x & 0x4000000 > 0) {
                result = (result * 0x10000000002C5C860) >> 64;
            }
            if (x & 0x2000000 > 0) {
                result = (result * 0x1000000000162E430) >> 64;
            }
            if (x & 0x1000000 > 0) {
                result = (result * 0x10000000000B17218) >> 64;
            }
        }

        if (x & 0xFF0000 > 0) {
            if (x & 0x800000 > 0) {
                result = (result * 0x1000000000058B90C) >> 64;
            }
            if (x & 0x400000 > 0) {
                result = (result * 0x100000000002C5C86) >> 64;
            }
            if (x & 0x200000 > 0) {
                result = (result * 0x10000000000162E43) >> 64;
            }
            if (x & 0x100000 > 0) {
                result = (result * 0x100000000000B1721) >> 64;
            }
            if (x & 0x80000 > 0) {
                result = (result * 0x10000000000058B91) >> 64;
            }
            if (x & 0x40000 > 0) {
                result = (result * 0x1000000000002C5C8) >> 64;
            }
            if (x & 0x20000 > 0) {
                result = (result * 0x100000000000162E4) >> 64;
            }
            if (x & 0x10000 > 0) {
                result = (result * 0x1000000000000B172) >> 64;
            }
        }

        if (x & 0xFF00 > 0) {
            if (x & 0x8000 > 0) {
                result = (result * 0x100000000000058B9) >> 64;
            }
            if (x & 0x4000 > 0) {
                result = (result * 0x10000000000002C5D) >> 64;
            }
            if (x & 0x2000 > 0) {
                result = (result * 0x1000000000000162E) >> 64;
            }
            if (x & 0x1000 > 0) {
                result = (result * 0x10000000000000B17) >> 64;
            }
            if (x & 0x800 > 0) {
                result = (result * 0x1000000000000058C) >> 64;
            }
            if (x & 0x400 > 0) {
                result = (result * 0x100000000000002C6) >> 64;
            }
            if (x & 0x200 > 0) {
                result = (result * 0x10000000000000163) >> 64;
            }
            if (x & 0x100 > 0) {
                result = (result * 0x100000000000000B1) >> 64;
            }
        }

        if (x & 0xFF > 0) {
            if (x & 0x80 > 0) {
                result = (result * 0x10000000000000059) >> 64;
            }
            if (x & 0x40 > 0) {
                result = (result * 0x1000000000000002C) >> 64;
            }
            if (x & 0x20 > 0) {
                result = (result * 0x10000000000000016) >> 64;
            }
            if (x & 0x10 > 0) {
                result = (result * 0x1000000000000000B) >> 64;
            }
            if (x & 0x8 > 0) {
                result = (result * 0x10000000000000006) >> 64;
            }
            if (x & 0x4 > 0) {
                result = (result * 0x10000000000000003) >> 64;
            }
            if (x & 0x2 > 0) {
                result = (result * 0x10000000000000001) >> 64;
            }
            if (x & 0x1 > 0) {
                result = (result * 0x10000000000000001) >> 64;
            }
        }

        // In the code snippet below, two operations are executed simultaneously:
        //
        // 1. The result is multiplied by $(2^n + 1)$, where $2^n$ represents the integer part, and the additional 1
        // accounts for the initial guess of 0.5. This is achieved by subtracting from 191 instead of 192.
        // 2. The result is then converted to an unsigned 60.18-decimal fixed-point format.
        //
        // The underlying logic is based on the relationship $2^{191-ip} = 2^{ip} / 2^{191}$, where $ip$ denotes the,
        // integer part, $2^n$.
        result *= UNIT;
        result >>= (191 - (x >> 64));
    }
}

/// @notice Finds the zero-based index of the first 1 in the binary representation of x.
///
/// @dev See the note on "msb" in this Wikipedia article: https://en.wikipedia.org/wiki/Find_first_set
///
/// Each step in this implementation is equivalent to this high-level code:
///
/// ```solidity
/// if (x >= 2 ** 128) {
///     x >>= 128;
///     result += 128;
/// }
/// ```
///
/// Where 128 is replaced with each respective power of two factor. See the full high-level implementation here:
/// https://gist.github.com/PaulRBerg/f932f8693f2733e30c4d479e8e980948
///
/// The Yul instructions used below are:
///
/// - "gt" is "greater than"
/// - "or" is the OR bitwise operator
/// - "shl" is "shift left"
/// - "shr" is "shift right"
///
/// @param x The uint256 number for which to find the index of the most significant bit.
/// @return result The index of the most significant bit as a uint256.
/// @custom:smtchecker abstract-function-nondet
function msb(uint256 x) pure returns (uint256 result) {
    // 2^128
    assembly ("memory-safe") {
        let factor := shl(7, gt(x, 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^64
    assembly ("memory-safe") {
        let factor := shl(6, gt(x, 0xFFFFFFFFFFFFFFFF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^32
    assembly ("memory-safe") {
        let factor := shl(5, gt(x, 0xFFFFFFFF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^16
    assembly ("memory-safe") {
        let factor := shl(4, gt(x, 0xFFFF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^8
    assembly ("memory-safe") {
        let factor := shl(3, gt(x, 0xFF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^4
    assembly ("memory-safe") {
        let factor := shl(2, gt(x, 0xF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^2
    assembly ("memory-safe") {
        let factor := shl(1, gt(x, 0x3))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^1
    // No need to shift x any more.
    assembly ("memory-safe") {
        let factor := gt(x, 0x1)
        result := or(result, factor)
    }
}

/// @notice Calculates x*y÷denominator with 512-bit precision.
///
/// @dev Credits to Remco Bloemen under MIT license https://xn--2-umb.com/21/muldiv.
///
/// Notes:
/// - The result is rounded toward zero.
///
/// Requirements:
/// - The denominator must not be zero.
/// - The result must fit in uint256.
///
/// @param x The multiplicand as a uint256.
/// @param y The multiplier as a uint256.
/// @param denominator The divisor as a uint256.
/// @return result The result as a uint256.
/// @custom:smtchecker abstract-function-nondet
function mulDiv(uint256 x, uint256 y, uint256 denominator) pure returns (uint256 result) {
    // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
    // use the Chinese Remainder Theorem to reconstruct the 512-bit result. The result is stored in two 256
    // variables such that product = prod1 * 2^256 + prod0.
    uint256 prod0; // Least significant 256 bits of the product
    uint256 prod1; // Most significant 256 bits of the product
    assembly ("memory-safe") {
        let mm := mulmod(x, y, not(0))
        prod0 := mul(x, y)
        prod1 := sub(sub(mm, prod0), lt(mm, prod0))
    }

    // Handle non-overflow cases, 256 by 256 division.
    if (prod1 == 0) {
        unchecked {
            return prod0 / denominator;
        }
    }

    // Make sure the result is less than 2^256. Also prevents denominator == 0.
    if (prod1 >= denominator) {
        revert PRBMath_MulDiv_Overflow(x, y, denominator);
    }

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

    // Make division exact by subtracting the remainder from [prod1 prod0].
    uint256 remainder;
    assembly ("memory-safe") {
        // Compute remainder using the mulmod Yul instruction.
        remainder := mulmod(x, y, denominator)

        // Subtract 256 bit number from 512-bit number.
        prod1 := sub(prod1, gt(remainder, prod0))
        prod0 := sub(prod0, remainder)
    }

    unchecked {
        // Calculate the largest power of two divisor of the denominator using the unary operator ~. This operation cannot overflow
        // because the denominator cannot be zero at this point in the function execution. The result is always >= 1.
        // For more detail, see https://cs.stackexchange.com/q/138556/92363.
        uint256 lpotdod = denominator & (~denominator + 1);
        uint256 flippedLpotdod;

        assembly ("memory-safe") {
            // Factor powers of two out of denominator.
            denominator := div(denominator, lpotdod)

            // Divide [prod1 prod0] by lpotdod.
            prod0 := div(prod0, lpotdod)

            // Get the flipped value `2^256 / lpotdod`. If the `lpotdod` is zero, the flipped value is one.
            // `sub(0, lpotdod)` produces the two's complement version of `lpotdod`, which is equivalent to flipping all the bits.
            // However, `div` interprets this value as an unsigned value: https://ethereum.stackexchange.com/q/147168/24693
            flippedLpotdod := add(div(sub(0, lpotdod), lpotdod), 1)
        }

        // Shift in bits from prod1 into prod0.
        prod0 |= prod1 * flippedLpotdod;

        // 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 for
        // four bits. That is, denominator * inv = 1 mod 2^4.
        uint256 inverse = (3 * denominator) ^ 2;

        // Use the 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.
        inverse *= 2 - denominator * inverse; // inverse mod 2^8
        inverse *= 2 - denominator * inverse; // inverse mod 2^16
        inverse *= 2 - denominator * inverse; // inverse mod 2^32
        inverse *= 2 - denominator * inverse; // inverse mod 2^64
        inverse *= 2 - denominator * inverse; // inverse mod 2^128
        inverse *= 2 - denominator * inverse; // 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 * inverse;
    }
}

/// @notice Calculates x*y÷1e18 with 512-bit precision.
///
/// @dev A variant of {mulDiv} with constant folding, i.e. in which the denominator is hard coded to 1e18.
///
/// Notes:
/// - The body is purposely left uncommented; to understand how this works, see the documentation in {mulDiv}.
/// - The result is rounded toward zero.
/// - We take as an axiom that the result cannot be `MAX_UINT256` when x and y solve the following system of equations:
///
/// $$
/// \begin{cases}
///     x * y = MAX\_UINT256 * UNIT \\
///     (x * y) \% UNIT \geq \frac{UNIT}{2}
/// \end{cases}
/// $$
///
/// Requirements:
/// - Refer to the requirements in {mulDiv}.
/// - The result must fit in uint256.
///
/// @param x The multiplicand as an unsigned 60.18-decimal fixed-point number.
/// @param y The multiplier as an unsigned 60.18-decimal fixed-point number.
/// @return result The result as an unsigned 60.18-decimal fixed-point number.
/// @custom:smtchecker abstract-function-nondet
function mulDiv18(uint256 x, uint256 y) pure returns (uint256 result) {
    uint256 prod0;
    uint256 prod1;
    assembly ("memory-safe") {
        let mm := mulmod(x, y, not(0))
        prod0 := mul(x, y)
        prod1 := sub(sub(mm, prod0), lt(mm, prod0))
    }

    if (prod1 == 0) {
        unchecked {
            return prod0 / UNIT;
        }
    }

    if (prod1 >= UNIT) {
        revert PRBMath_MulDiv18_Overflow(x, y);
    }

    uint256 remainder;
    assembly ("memory-safe") {
        remainder := mulmod(x, y, UNIT)
        result :=
            mul(
                or(
                    div(sub(prod0, remainder), UNIT_LPOTD),
                    mul(sub(prod1, gt(remainder, prod0)), add(div(sub(0, UNIT_LPOTD), UNIT_LPOTD), 1))
                ),
                UNIT_INVERSE
            )
    }
}

/// @notice Calculates x*y÷denominator with 512-bit precision.
///
/// @dev This is an extension of {mulDiv} for signed numbers, which works by computing the signs and the absolute values separately.
///
/// Notes:
/// - The result is rounded toward zero.
///
/// Requirements:
/// - Refer to the requirements in {mulDiv}.
/// - None of the inputs can be `type(int256).min`.
/// - The result must fit in int256.
///
/// @param x The multiplicand as an int256.
/// @param y The multiplier as an int256.
/// @param denominator The divisor as an int256.
/// @return result The result as an int256.
/// @custom:smtchecker abstract-function-nondet
function mulDivSigned(int256 x, int256 y, int256 denominator) pure returns (int256 result) {
    if (x == type(int256).min || y == type(int256).min || denominator == type(int256).min) {
        revert PRBMath_MulDivSigned_InputTooSmall();
    }

    // Get hold of the absolute values of x, y and the denominator.
    uint256 xAbs;
    uint256 yAbs;
    uint256 dAbs;
    unchecked {
        xAbs = x < 0 ? uint256(-x) : uint256(x);
        yAbs = y < 0 ? uint256(-y) : uint256(y);
        dAbs = denominator < 0 ? uint256(-denominator) : uint256(denominator);
    }

    // Compute the absolute value of x*y÷denominator. The result must fit in int256.
    uint256 resultAbs = mulDiv(xAbs, yAbs, dAbs);
    if (resultAbs > uint256(type(int256).max)) {
        revert PRBMath_MulDivSigned_Overflow(x, y);
    }

    // Get the signs of x, y and the denominator.
    uint256 sx;
    uint256 sy;
    uint256 sd;
    assembly ("memory-safe") {
        // "sgt" is the "signed greater than" assembly instruction and "sub(0,1)" is -1 in two's complement.
        sx := sgt(x, sub(0, 1))
        sy := sgt(y, sub(0, 1))
        sd := sgt(denominator, sub(0, 1))
    }

    // XOR over sx, sy and sd. What this does is to check whether there are 1 or 3 negative signs in the inputs.
    // If there are, the result should be negative. Otherwise, it should be positive.
    unchecked {
        result = sx ^ sy ^ sd == 0 ? -int256(resultAbs) : int256(resultAbs);
    }
}

/// @notice Calculates the square root of x using the Babylonian method.
///
/// @dev See https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method.
///
/// Notes:
/// - If x is not a perfect square, the result is rounded down.
/// - Credits to OpenZeppelin for the explanations in comments below.
///
/// @param x The uint256 number for which to calculate the square root.
/// @return result The result as a uint256.
/// @custom:smtchecker abstract-function-nondet
function sqrt(uint256 x) pure returns (uint256 result) {
    if (x == 0) {
        return 0;
    }

    // For our first guess, we calculate the biggest power of 2 which is smaller than the square root of x.
    //
    // We know that the "msb" (most significant bit) of x is a power of 2 such that we have:
    //
    // $$
    // msb(x) <= x <= 2*msb(x)$
    // $$
    //
    // We write $msb(x)$ as $2^k$, and we get:
    //
    // $$
    // k = log_2(x)
    // $$
    //
    // Thus, we can write the initial inequality as:
    //
    // $$
    // 2^{log_2(x)} <= x <= 2*2^{log_2(x)+1} \\
    // sqrt(2^k) <= sqrt(x) < sqrt(2^{k+1}) \\
    // 2^{k/2} <= sqrt(x) < 2^{(k+1)/2} <= 2^{(k/2)+1}
    // $$
    //
    // Consequently, $2^{log_2(x) /2} is a good first approximation of sqrt(x) with at least one correct bit.
    uint256 xAux = uint256(x);
    result = 1;
    if (xAux >= 2 ** 128) {
        xAux >>= 128;
        result <<= 64;
    }
    if (xAux >= 2 ** 64) {
        xAux >>= 64;
        result <<= 32;
    }
    if (xAux >= 2 ** 32) {
        xAux >>= 32;
        result <<= 16;
    }
    if (xAux >= 2 ** 16) {
        xAux >>= 16;
        result <<= 8;
    }
    if (xAux >= 2 ** 8) {
        xAux >>= 8;
        result <<= 4;
    }
    if (xAux >= 2 ** 4) {
        xAux >>= 4;
        result <<= 2;
    }
    if (xAux >= 2 ** 2) {
        result <<= 1;
    }

    // At this point, `result` is an estimation with at least one bit of precision. We know the true value has at
    // most 128 bits, since it is the square root of a uint256. Newton's method converges quadratically (precision
    // doubles at every iteration). We thus need at most 7 iteration to turn our partial result with one bit of
    // precision into the expected uint128 result.
    unchecked {
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;

        // If x is not a perfect square, round the result toward zero.
        uint256 roundedResult = x / result;
        if (result >= roundedResult) {
            result = roundedResult;
        }
    }
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

import { UD2x18 } from "./ValueType.sol";

/// @dev Euler's number as a UD2x18 number.
UD2x18 constant E = UD2x18.wrap(2_718281828459045235);

/// @dev The maximum value a UD2x18 number can have.
uint64 constant uMAX_UD2x18 = 18_446744073709551615;
UD2x18 constant MAX_UD2x18 = UD2x18.wrap(uMAX_UD2x18);

/// @dev PI as a UD2x18 number.
UD2x18 constant PI = UD2x18.wrap(3_141592653589793238);

/// @dev The unit number, which gives the decimal precision of UD2x18.
uint256 constant uUNIT = 1e18;
UD2x18 constant UNIT = UD2x18.wrap(1e18);

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^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 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) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

import { uMAX_UD60x18, uUNIT } from "./Constants.sol";
import { PRBMath_UD60x18_Convert_Overflow } from "./Errors.sol";
import { UD60x18 } from "./ValueType.sol";

/// @notice Converts a UD60x18 number to a simple integer by dividing it by `UNIT`.
/// @dev The result is rounded toward zero.
/// @param x The UD60x18 number to convert.
/// @return result The same number in basic integer form.
function convert(UD60x18 x) pure returns (uint256 result) {
    result = UD60x18.unwrap(x) / uUNIT;
}

/// @notice Converts a simple integer to UD60x18 by multiplying it by `UNIT`.
///
/// @dev Requirements:
/// - x must be less than or equal to `MAX_UD60x18 / UNIT`.
///
/// @param x The basic integer to convert.
/// @param result The same number converted to UD60x18.
function convert(uint256 x) pure returns (UD60x18 result) {
    if (x > uMAX_UD60x18 / uUNIT) {
        revert PRBMath_UD60x18_Convert_Overflow(x);
    }
    unchecked {
        result = UD60x18.wrap(x * uUNIT);
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)

pragma solidity ^0.8.0;

/**
 * @title Counters
 * @author Matt Condon (@shrugs)
 * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
 * of elements in a mapping, issuing ERC721 ids, or counting request ids.
 *
 * Include with `using Counters for Counters.Counter;`
 */
library Counters {
    struct Counter {
        // This variable should never be directly accessed by users of the library: interactions must be restricted to
        // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
        // this feature: see https://github.com/ethereum/solidity/issues/4637
        uint256 _value; // default: 0
    }

    function current(Counter storage counter) internal view returns (uint256) {
        return counter._value;
    }

    function increment(Counter storage counter) internal {
        unchecked {
            counter._value += 1;
        }
    }

    function decrement(Counter storage counter) internal {
        uint256 value = counter._value;
        require(value > 0, "Counter: decrement overflow");
        unchecked {
            counter._value = value - 1;
        }
    }

    function reset(Counter storage counter) internal {
        counter._value = 0;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

// https://github.com/curvefi/tricrypto-ng/blob/0bc1191b6097c8854e4f09e385f6c2c79a5bb773/contracts/main/CurveTricryptoOptimizedWETH.vy

import {IERC20} from "@openzeppelin/contracts@4.9.3/token/ERC20/IERC20.sol";

interface CurveTricryptoOptimizedWETH is IERC20 {
    /// @notice Exchange using wrapped native token by default
    /// @param i Index value for the input coin
    /// @param j Index value for the output coin
    /// @param dx Amount of input coin being swapped in
    /// @param min_dy Minimum amount of output coin to receive
    /// @param use_eth True if the input coin is native token, False otherwise
    /// @param receiver Address to send the output coin to. Default is msg.sender
    /// @return uint256 Amount of tokens at index j received by the `receiver
    function exchange(uint256 i, uint256 j, uint256 dx, uint256 min_dy, bool use_eth, address receiver)
        external
        payable
        returns (uint256);

    /// @notice Exchange with callback method.
    /// @dev This method does not allow swapping in native token, but does allow
    /// swaps that transfer out native token from the pool.
    /// @dev Does not allow flashloans
    /// @dev One use-case is to reduce the number of redundant ERC20 token
    /// transfers in zaps.
    /// @param i Index value for the input coin
    /// @param j Index value for the output coin
    /// @param dx Amount of input coin being swapped in
    /// @param min_dy Minimum amount of output coin to receive
    /// @param use_eth True if output is native token, False otherwise
    /// @param sender Address to transfer input coin from
    /// @param receiver Address to send the output coin to
    /// @param cb Callback signature
    /// @return uint256 Amount of tokens at index j received by the `receiver`
    function exchange_extended(
        uint256 i,
        uint256 j,
        uint256 dx,
        uint256 min_dy,
        bool use_eth,
        address sender,
        address receiver,
        bytes32 cb
    ) external returns (uint256);

    /// @notice Adds liquidity into the pool.
    /// @param amounts Amounts of each coin to add.
    /// @param min_mint_amount Minimum amount of LP to mint.
    function add_liquidity(uint256[3] calldata amounts, uint256 min_mint_amount) external payable returns (uint256);

    /// @notice Adds liquidity into the pool.
    /// @param amounts Amounts of each coin to add.
    /// @param min_mint_amount Minimum amount of LP to mint.
    /// @return uint256 Amount of LP tokens received by the `receiver
    /// @param use_eth True if native token is being added to the pool.
    /// @param receiver Address to send the LP tokens to. Default is msg.sender
    function add_liquidity(uint256[3] calldata amounts, uint256 min_mint_amount, bool use_eth, address receiver)
        external
        payable
        returns (uint256);

    /// @notice This withdrawal method is very safe, does no complex math since
    ///         tokens are withdrawn in balanced proportions. No fees are charged.
    /// @param amount Amount of LP tokens to burn
    /// @param min_amounts Minimum amounts of tokens to withdraw
    /// @param use_eth Whether to withdraw ETH or not
    /// @param receiver Address to send the withdrawn tokens to
    /// @param claim_admin_fees If True, call self._claim_admin_fees(). Default is True.
    /// @return uint256[3] Amount of pool tokens received by the `receiver`
    function remove_liquidity(
        uint256 amount,
        uint256[3] calldata min_amounts,
        bool use_eth,
        address receiver,
        bool claim_admin_fees
    ) external returns (uint256[3] memory);

    /// @notice Withdraw liquidity in a single token.
    /// Involves fees (lower than swap fees).
    /// @dev This operation also involves an admin fee claim.
    /// @param token_amount Amount of LP tokens to burn
    /// @param i Index of the token to withdraw
    /// @param min_amount Minimum amount of token to withdraw.
    /// @param use_eth Whether to withdraw ETH or not
    /// @param receiver Address to send the withdrawn tokens to
    /// @return Amount of tokens at index i received by the `receiver`
    function remove_liquidity_one_coin(
        uint256 token_amount,
        uint256 i,
        uint256 min_amount,
        bool use_eth,
        address receiver
    ) external returns (uint256);

    ///////////////////////////////////////////////////////////
    // View methods
    ///////////////////////////////////////////////////////////

    /// @notice Returns the balance of the coin at index `i`
    function balances(uint256 i) external view returns (uint256);

    /// @notice Calculate LP tokens minted or to be burned for depositing or
    ///         removing `amounts` of coins
    /// @dev Includes fee.
    /// @param amounts Amounts of tokens being deposited or withdrawn
    /// @param deposit True if it is a deposit action, False if withdrawn.
    /// @return uint256 Amount of LP tokens deposited or withdrawn.
    function calc_token_amount(uint256[3] calldata amounts, bool deposit) external view returns (uint256);

    function get_dy(uint256 i, uint256 j, uint256 dx) external view returns (uint256);

    function get_dx(uint256 i, uint256 j, uint256 dy) external view returns (uint256);

    /// @notice Calculates the current price of the LP token with respect to the coin at the 0th index
    /// @dev This function should be implemented to return the LP price
    /// @return The current LP price as a uint256
    function lp_price() external view returns (uint256);

    /// @notice calculate the current virtual price of the pool's LP token (in 18 decimals)
    /// @dev Non read-reenrant.
    /// @dev https://docs.curve.fi/cryptoswap-exchange/tricrypto-ng/pools/tricrypto/?h=virtual#get_virtual_price
    function get_virtual_price() external view returns (uint256);

    /// @notice Returns the oracle price of the coin at index `k` with respect to the coin at index 0
    /// @dev The oracle is an exponential moving average, with a periodicity determined internally.
    ///      The aggregated prices are cached state prices (dy/dx) calculated AFTER the latest trade.
    /// @param k The index of the coin for which the oracle price is needed (k = 0 or 1)
    /// @return The oracle price of the coin at index `k` as a uint256
    function price_oracle(uint256 k) external view returns (uint256);

    /// @notice Calculates output tokens with fee
    /// @param token_amount LP Token amount to burn
    /// @param i token in which liquidity is withdrawn
    /// @return uint256 Amount of ith tokens received for burning token_amount LP tokens.
    function calc_withdraw_one_coin(uint256 token_amount, uint256 i) external view returns (uint256);

    function calc_token_fee(uint256[3] calldata amounts, uint256[3] calldata xp) external view returns (uint256);

    function fee_calc(uint256[3] calldata xp) external view returns (uint256);

    /// @notice Returns i-th coin address.
    /// @param i Index of the coin. i must be 0, 1 or 2.
    function coins(uint256 i) external view returns (address);

    /// @dev Returns the address of the factory that created the pool.
    /// @return address The factory address.
    function factory() external view returns (address);

    function D() external view returns (uint256);

    /// @dev Returns the cached virtual price of the pool.
    function virtual_price() external view returns (uint256);

    /// @dev Returns the current pool amplification parameter.
    /// @return uint256 The A parameter.
    function A() external view returns (uint256);

    /// @dev Returns the current pool gamma parameter.
    /// @return uint256 The gamma parameter.
    function gamma() external view returns (uint256);

    ///////////////////////////////////////////////////////////
    // Protected methods
    ///////////////////////////////////////////////////////////

    /// @notice Initialise Ramping A and gamma parameter values linearly.
    /// @dev Only accessible by factory admin, and only
    /// @param future_A The future A value.
    /// @param future_gamma The future gamma value.
    /// @param future_time The timestamp at which the ramping will end.
    function ramp_A_gamma(uint256 future_A, uint256 future_gamma, uint256 future_time) external;
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.0;

library DecimalConversion {
    /// @dev Turns a token into 18 point decimal
    /// @param amount The amount of the token in native decimal encoding
    /// @param decimals The token decimals (MUST be less than 18)
    /// @return The amount of token encoded into 18 point fixed point
    function to18Decimals(uint256 amount, uint8 decimals) internal pure returns (uint256) {
        // we shift left by the difference
        return amount * 10 ** (18 - decimals);
    }

    /// @dev Turns an 18 fixed point amount into a token amount
    /// @param amount The amount of the token in 18 decimal fixed point
    /// @param decimals The token decimals (MUST be less than 18)
    /// @return The amount of token encoded in native decimal point
    function from18Decimals(uint256 amount, uint8 decimals) internal pure returns (uint256) {
        // we shift right the amount by the number of decimals
        return amount / 10 ** (18 - decimals);
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/cryptography/ECDSA.sol)

pragma solidity ^0.8.0;

import "../Strings.sol";

/**
 * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
 *
 * These functions can be used to verify that a message was signed by the holder
 * of the private keys of a given address.
 */
library ECDSA {
    enum RecoverError {
        NoError,
        InvalidSignature,
        InvalidSignatureLength,
        InvalidSignatureS,
        InvalidSignatureV // Deprecated in v4.8
    }

    function _throwError(RecoverError error) private pure {
        if (error == RecoverError.NoError) {
            return; // no error: do nothing
        } else if (error == RecoverError.InvalidSignature) {
            revert("ECDSA: invalid signature");
        } else if (error == RecoverError.InvalidSignatureLength) {
            revert("ECDSA: invalid signature length");
        } else if (error == RecoverError.InvalidSignatureS) {
            revert("ECDSA: invalid signature 's' value");
        }
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature` or error string. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     *
     * Documentation for signature generation:
     * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
     * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
        if (signature.length == 65) {
            bytes32 r;
            bytes32 s;
            uint8 v;
            // ecrecover takes the signature parameters, and the only way to get them
            // currently is to use assembly.
            /// @solidity memory-safe-assembly
            assembly {
                r := mload(add(signature, 0x20))
                s := mload(add(signature, 0x40))
                v := byte(0, mload(add(signature, 0x60)))
            }
            return tryRecover(hash, v, r, s);
        } else {
            return (address(0), RecoverError.InvalidSignatureLength);
        }
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, signature);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
     *
     * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address, RecoverError) {
        bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
        uint8 v = uint8((uint256(vs) >> 255) + 27);
        return tryRecover(hash, v, r, s);
    }

    /**
     * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
     *
     * _Available since v4.2._
     */
    function recover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, r, vs);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
     * `r` and `s` signature fields separately.
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address, RecoverError) {
        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            return (address(0), RecoverError.InvalidSignatureS);
        }

        // If the signature is valid (and not malleable), return the signer address
        address signer = ecrecover(hash, v, r, s);
        if (signer == address(0)) {
            return (address(0), RecoverError.InvalidSignature);
        }

        return (signer, RecoverError.NoError);
    }

    /**
     * @dev Overload of {ECDSA-recover} that receives the `v`,
     * `r` and `s` signature fields separately.
     */
    function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Returns an Ethereum Signed Message, created from a `hash`. This
     * produces hash corresponding to the one signed with the
     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
     * JSON-RPC method as part of EIP-191.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32 message) {
        // 32 is the length in bytes of hash,
        // enforced by the type signature above
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, "\x19Ethereum Signed Message:\n32")
            mstore(0x1c, hash)
            message := keccak256(0x00, 0x3c)
        }
    }

    /**
     * @dev Returns an Ethereum Signed Message, created from `s`. This
     * produces hash corresponding to the one signed with the
     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
     * JSON-RPC method as part of EIP-191.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
    }

    /**
     * @dev Returns an Ethereum Signed Typed Data, created from a
     * `domainSeparator` and a `structHash`. This produces hash corresponding
     * to the one signed with the
     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
     * JSON-RPC method as part of EIP-712.
     *
     * See {recover}.
     */
    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32 data) {
        /// @solidity memory-safe-assembly
        assembly {
            let ptr := mload(0x40)
            mstore(ptr, "\x19\x01")
            mstore(add(ptr, 0x02), domainSeparator)
            mstore(add(ptr, 0x22), structHash)
            data := keccak256(ptr, 0x42)
        }
    }

    /**
     * @dev Returns an Ethereum Signed Data with intended validator, created from a
     * `validator` and `data` according to the version 0 of EIP-191.
     *
     * See {recover}.
     */
    function toDataWithIntendedValidatorHash(address validator, bytes memory data) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19\x00", validator, data));
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/cryptography/EIP712.sol)

pragma solidity ^0.8.8;

import "./ECDSA.sol";
import "../ShortStrings.sol";
import "../../interfaces/IERC5267.sol";

/**
 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
 *
 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
 *
 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
 * ({_hashTypedDataV4}).
 *
 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
 * the chain id to protect against replay attacks on an eventual fork of the chain.
 *
 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
 *
 * NOTE: In the upgradeable version of this contract, the cached values will correspond to the address, and the domain
 * separator of the implementation contract. This will cause the `_domainSeparatorV4` function to always rebuild the
 * separator from the immutable values, which is cheaper than accessing a cached version in cold storage.
 *
 * _Available since v3.4._
 *
 * @custom:oz-upgrades-unsafe-allow state-variable-immutable state-variable-assignment
 */
abstract contract EIP712 is IERC5267 {
    using ShortStrings for *;

    bytes32 private constant _TYPE_HASH =
        keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");

    // Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
    // invalidate the cached domain separator if the chain id changes.
    bytes32 private immutable _cachedDomainSeparator;
    uint256 private immutable _cachedChainId;
    address private immutable _cachedThis;

    bytes32 private immutable _hashedName;
    bytes32 private immutable _hashedVersion;

    ShortString private immutable _name;
    ShortString private immutable _version;
    string private _nameFallback;
    string private _versionFallback;

    /**
     * @dev Initializes the domain separator and parameter caches.
     *
     * The meaning of `name` and `version` is specified in
     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
     *
     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
     * - `version`: the current major version of the signing domain.
     *
     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
     * contract upgrade].
     */
    constructor(string memory name, string memory version) {
        _name = name.toShortStringWithFallback(_nameFallback);
        _version = version.toShortStringWithFallback(_versionFallback);
        _hashedName = keccak256(bytes(name));
        _hashedVersion = keccak256(bytes(version));

        _cachedChainId = block.chainid;
        _cachedDomainSeparator = _buildDomainSeparator();
        _cachedThis = address(this);
    }

    /**
     * @dev Returns the domain separator for the current chain.
     */
    function _domainSeparatorV4() internal view returns (bytes32) {
        if (address(this) == _cachedThis && block.chainid == _cachedChainId) {
            return _cachedDomainSeparator;
        } else {
            return _buildDomainSeparator();
        }
    }

    function _buildDomainSeparator() private view returns (bytes32) {
        return keccak256(abi.encode(_TYPE_HASH, _hashedName, _hashedVersion, block.chainid, address(this)));
    }

    /**
     * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
     * function returns the hash of the fully encoded EIP712 message for this domain.
     *
     * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
     *
     * ```solidity
     * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
     *     keccak256("Mail(address to,string contents)"),
     *     mailTo,
     *     keccak256(bytes(mailContents))
     * )));
     * address signer = ECDSA.recover(digest, signature);
     * ```
     */
    function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
        return ECDSA.toTypedDataHash(_domainSeparatorV4(), structHash);
    }

    /**
     * @dev See {EIP-5267}.
     *
     * _Available since v4.9._
     */
    function eip712Domain()
        public
        view
        virtual
        override
        returns (
            bytes1 fields,
            string memory name,
            string memory version,
            uint256 chainId,
            address verifyingContract,
            bytes32 salt,
            uint256[] memory extensions
        )
    {
        return (
            hex"0f", // 01111
            _name.toStringWithFallback(_nameFallback),
            _version.toStringWithFallback(_versionFallback),
            block.chainid,
            address(this),
            bytes32(0),
            new uint256[](0)
        );
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;

import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * The default value of {decimals} is 18. To change this, you should override
 * this function so it returns a different value.
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the default value returned by this function, unless
     * it's overridden.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    /**
     * @dev Moves `amount` of tokens from `from` to `to`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     */
    function _transfer(address from, address to, uint256 amount) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
            // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
            // decrementing then incrementing.
            _balances[to] += amount;
        }

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        unchecked {
            // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
            _balances[account] += amount;
        }
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
            // Overflow not possible: amount <= accountBalance <= totalSupply.
            _totalSupply -= amount;
        }

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
     *
     * Does not update the allowance amount in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Might emit an {Approval} event.
     */
    function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {}
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/ERC20Permit.sol)

pragma solidity ^0.8.0;

import "./IERC20Permit.sol";
import "../ERC20.sol";
import "../../../utils/cryptography/ECDSA.sol";
import "../../../utils/cryptography/EIP712.sol";
import "../../../utils/Counters.sol";

/**
 * @dev Implementation 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.
 *
 * _Available since v3.4._
 */
abstract contract ERC20Permit is ERC20, IERC20Permit, EIP712 {
    using Counters for Counters.Counter;

    mapping(address => Counters.Counter) private _nonces;

    // solhint-disable-next-line var-name-mixedcase
    bytes32 private constant _PERMIT_TYPEHASH =
        keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    /**
     * @dev In previous versions `_PERMIT_TYPEHASH` was declared as `immutable`.
     * However, to ensure consistency with the upgradeable transpiler, we will continue
     * to reserve a slot.
     * @custom:oz-renamed-from _PERMIT_TYPEHASH
     */
    // solhint-disable-next-line var-name-mixedcase
    bytes32 private _PERMIT_TYPEHASH_DEPRECATED_SLOT;

    /**
     * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
     *
     * It's a good idea to use the same `name` that is defined as the ERC20 token name.
     */
    constructor(string memory name) EIP712(name, "1") {}

    /**
     * @dev See {IERC20Permit-permit}.
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual override {
        require(block.timestamp <= deadline, "ERC20Permit: expired deadline");

        bytes32 structHash = keccak256(abi.encode(_PERMIT_TYPEHASH, owner, spender, value, _useNonce(owner), deadline));

        bytes32 hash = _hashTypedDataV4(structHash);

        address signer = ECDSA.recover(hash, v, r, s);
        require(signer == owner, "ERC20Permit: invalid signature");

        _approve(owner, spender, value);
    }

    /**
     * @dev See {IERC20Permit-nonces}.
     */
    function nonces(address owner) public view virtual override returns (uint256) {
        return _nonces[owner].current();
    }

    /**
     * @dev See {IERC20Permit-DOMAIN_SEPARATOR}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view override returns (bytes32) {
        return _domainSeparatorV4();
    }

    /**
     * @dev "Consume a nonce": return the current value and increment.
     *
     * _Available since v4.1._
     */
    function _useNonce(address owner) internal virtual returns (uint256 current) {
        Counters.Counter storage nonce = _nonces[owner];
        current = nonce.current();
        nonce.increment();
    }
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

import { UD2x18 } from "./ValueType.sol";

/// @notice Thrown when trying to cast a UD2x18 number that doesn't fit in SD1x18.
error PRBMath_UD2x18_IntoSD1x18_Overflow(UD2x18 x);

/// @notice Thrown when trying to cast a UD2x18 number that doesn't fit in uint40.
error PRBMath_UD2x18_IntoUint40_Overflow(UD2x18 x);

// SPDX-License-Identifier: AGPL-3.0-only
/// @notice Taken from: https://github.com/transmissions11/solmate/blob/2001af43aedb46fdc2335d2a7714fb2dae7cfcd1/src/utils/FixedPointMathLib.sol

pragma solidity >=0.8.0;

/// @notice Arithmetic library with operations for fixed-point numbers.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/FixedPointMathLib.sol)
/// @author Inspired by USM (https://github.com/usmfum/USM/blob/master/contracts/WadMath.sol)
library FixedPointMathLib {
    /*//////////////////////////////////////////////////////////////
                    SIMPLIFIED FIXED POINT OPERATIONS
    //////////////////////////////////////////////////////////////*/

    uint256 internal constant MAX_UINT256 = 2 ** 256 - 1;

    uint256 internal constant WAD = 1e18; // The scalar of ETH and most ERC20s.

    function mulWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
        return mulDivDown(x, y, WAD); // Equivalent to (x * y) / WAD rounded down.
    }

    function mulWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
        return mulDivUp(x, y, WAD); // Equivalent to (x * y) / WAD rounded up.
    }

    function divWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
        return mulDivDown(x, WAD, y); // Equivalent to (x * WAD) / y rounded down.
    }

    function divWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
        return mulDivUp(x, WAD, y); // Equivalent to (x * WAD) / y rounded up.
    }

    /*//////////////////////////////////////////////////////////////
                    LOW LEVEL FIXED POINT OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function mulDivDown(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            // Equivalent to require(denominator != 0 && (y == 0 || x <= type(uint256).max / y))
            if iszero(mul(denominator, iszero(mul(y, gt(x, div(MAX_UINT256, y)))))) {
                revert(0, 0)
            }

            // Divide x * y by the denominator.
            z := div(mul(x, y), denominator)
        }
    }

    function mulDivUp(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            // Equivalent to require(denominator != 0 && (y == 0 || x <= type(uint256).max / y))
            if iszero(mul(denominator, iszero(mul(y, gt(x, div(MAX_UINT256, y)))))) {
                revert(0, 0)
            }

            // If x * y modulo the denominator is strictly greater than 0,
            // 1 is added to round up the division of x * y by the denominator.
            z := add(gt(mod(mul(x, y), denominator), 0), div(mul(x, y), denominator))
        }
    }

    function rpow(uint256 x, uint256 n, uint256 scalar) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            switch x
            case 0 {
                switch n
                case 0 {
                    // 0 ** 0 = 1
                    z := scalar
                }
                default {
                    // 0 ** n = 0
                    z := 0
                }
            }
            default {
                switch mod(n, 2)
                case 0 {
                    // If n is even, store scalar in z for now.
                    z := scalar
                }
                default {
                    // If n is odd, store x in z for now.
                    z := x
                }

                // Shifting right by 1 is like dividing by 2.
                let half := shr(1, scalar)

                for {
                    // Shift n right by 1 before looping to halve it.
                    n := shr(1, n)
                } n {
                    // Shift n right by 1 each iteration to halve it.
                    n := shr(1, n)
                } {
                    // Revert immediately if x ** 2 would overflow.
                    // Equivalent to iszero(eq(div(xx, x), x)) here.
                    if shr(128, x) {
                        revert(0, 0)
                    }

                    // Store x squared.
                    let xx := mul(x, x)

                    // Round to the nearest number.
                    let xxRound := add(xx, half)

                    // Revert if xx + half overflowed.
                    if lt(xxRound, xx) {
                        revert(0, 0)
                    }

                    // Set x to scaled xxRound.
                    x := div(xxRound, scalar)

                    // If n is even:
                    if mod(n, 2) {
                        // Compute z * x.
                        let zx := mul(z, x)

                        // If z * x overflowed:
                        if iszero(eq(div(zx, x), z)) {
                            // Revert if x is non-zero.
                            if iszero(iszero(x)) {
                                revert(0, 0)
                            }
                        }

                        // Round to the nearest number.
                        let zxRound := add(zx, half)

                        // Revert if zx + half overflowed.
                        if lt(zxRound, zx) {
                            revert(0, 0)
                        }

                        // Return properly scaled zxRound.
                        z := div(zxRound, scalar)
                    }
                }
            }
        }
    }

    /*//////////////////////////////////////////////////////////////
                        GENERAL NUMBER UTILITIES
    //////////////////////////////////////////////////////////////*/

    function sqrt(uint256 x) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            let y := x // We start y at x, which will help us make our initial estimate.

            z := 181 // The "correct" value is 1, but this saves a multiplication later.

            // This segment is to get a reasonable initial estimate for the Babylonian method. With a bad
            // start, the correct # of bits increases ~linearly each iteration instead of ~quadratically.

            // We check y >= 2^(k + 8) but shift right by k bits
            // each branch to ensure that if x >= 256, then y >= 256.
            if iszero(lt(y, 0x10000000000000000000000000000000000)) {
                y := shr(128, y)
                z := shl(64, z)
            }
            if iszero(lt(y, 0x1000000000000000000)) {
                y := shr(64, y)
                z := shl(32, z)
            }
            if iszero(lt(y, 0x10000000000)) {
                y := shr(32, y)
                z := shl(16, z)
            }
            if iszero(lt(y, 0x1000000)) {
                y := shr(16, y)
                z := shl(8, z)
            }

            // Goal was to get z*z*y within a small factor of x. More iterations could
            // get y in a tighter range. Currently, we will have y in [256, 256*2^16).
            // We ensured y >= 256 so that the relative difference between y and y+1 is small.
            // That's not possible if x < 256 but we can just verify those cases exhaustively.

            // Now, z*z*y <= x < z*z*(y+1), and y <= 2^(16+8), and either y >= 256, or x < 256.
            // Correctness can be checked exhaustively for x < 256, so we assume y >= 256.
            // Then z*sqrt(y) is within sqrt(257)/sqrt(256) of sqrt(x), or about 20bps.

            // For s in the range [1/256, 256], the estimate f(s) = (181/1024) * (s+1) is in the range
            // (1/2.84 * sqrt(s), 2.84 * sqrt(s)), with largest error when s = 1 and when s = 256 or 1/256.

            // Since y is in [256, 256*2^16), let a = y/65536, so that a is in [1/256, 256). Then we can estimate
            // sqrt(y) using sqrt(65536) * 181/1024 * (a + 1) = 181/4 * (y + 65536)/65536 = 181 * (y + 65536)/2^18.

            // There is no overflow risk here since y < 2^136 after the first branch above.
            z := shr(18, mul(z, add(y, 65536))) // A mul() is saved from starting z at 181.

            // Given the worst case multiplicative error of 2.84 above, 7 iterations should be enough.
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))

            // If x+1 is a perfect square, the Babylonian method cycles between
            // floor(sqrt(x)) and ceil(sqrt(x)). This statement ensures we return floor.
            // See: https://en.wikipedia.org/wiki/Integer_square_root#Using_only_integer_division
            // Since the ceil is rare, we save gas on the assignment and repeat division in the rare case.
            // If you don't care whether the floor or ceil square root is returned, you can remove this statement.
            z := sub(z, lt(div(x, z), z))
        }
    }

    function unsafeMod(uint256 x, uint256 y) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            // Mod x by y. Note this will return
            // 0 instead of reverting if y is zero.
            z := mod(x, y)
        }
    }

    function unsafeDiv(uint256 x, uint256 y) internal pure returns (uint256 r) {
        /// @solidity memory-safe-assembly
        assembly {
            // Divide x by y. Note this will return
            // 0 instead of reverting if y is zero.
            r := div(x, y)
        }
    }

    function unsafeDivUp(uint256 x, uint256 y) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            // Add 1 to x * y if x % y > 0. Note this will
            // return 0 instead of reverting if y is zero.
            z := add(gt(mod(x, y), 0), div(x, y))
        }
    }
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

import { wrap } from "./Casting.sol";
import { UD60x18 } from "./ValueType.sol";

/// @notice Implements the checked addition operation (+) in the UD60x18 type.
function add(UD60x18 x, UD60x18 y) pure returns (UD60x18 result) {
    result = wrap(x.unwrap() + y.unwrap());
}

/// @notice Implements the AND (&) bitwise operation in the UD60x18 type.
function and(UD60x18 x, uint256 bits) pure returns (UD60x18 result) {
    result = wrap(x.unwrap() & bits);
}

/// @notice Implements the AND (&) bitwise operation in the UD60x18 type.
function and2(UD60x18 x, UD60x18 y) pure returns (UD60x18 result) {
    result = wrap(x.unwrap() & y.unwrap());
}

/// @notice Implements the equal operation (==) in the UD60x18 type.
function eq(UD60x18 x, UD60x18 y) pure returns (bool result) {
    result = x.unwrap() == y.unwrap();
}

/// @notice Implements the greater than operation (>) in the UD60x18 type.
function gt(UD60x18 x, UD60x18 y) pure returns (bool result) {
    result = x.unwrap() > y.unwrap();
}

/// @notice Implements the greater than or equal to operation (>=) in the UD60x18 type.
function gte(UD60x18 x, UD60x18 y) pure returns (bool result) {
    result = x.unwrap() >= y.unwrap();
}

/// @notice Implements a zero comparison check function in the UD60x18 type.
function isZero(UD60x18 x) pure returns (bool result) {
    // This wouldn't work if x could be negative.
    result = x.unwrap() == 0;
}

/// @notice Implements the left shift operation (<<) in the UD60x18 type.
function lshift(UD60x18 x, uint256 bits) pure returns (UD60x18 result) {
    result = wrap(x.unwrap() << bits);
}

/// @notice Implements the lower than operation (<) in the UD60x18 type.
function lt(UD60x18 x, UD60x18 y) pure returns (bool result) {
    result = x.unwrap() < y.unwrap();
}

/// @notice Implements the lower than or equal to operation (<=) in the UD60x18 type.
function lte(UD60x18 x, UD60x18 y) pure returns (bool result) {
    result = x.unwrap() <= y.unwrap();
}

/// @notice Implements the checked modulo operation (%) in the UD60x18 type.
function mod(UD60x18 x, UD60x18 y) pure returns (UD60x18 result) {
    result = wrap(x.unwrap() % y.unwrap());
}

/// @notice Implements the not equal operation (!=) in the UD60x18 type.
function neq(UD60x18 x, UD60x18 y) pure returns (bool result) {
    result = x.unwrap() != y.unwrap();
}

/// @notice Implements the NOT (~) bitwise operation in the UD60x18 type.
function not(UD60x18 x) pure returns (UD60x18 result) {
    result = wrap(~x.unwrap());
}

/// @notice Implements the OR (|) bitwise operation in the UD60x18 type.
function or(UD60x18 x, UD60x18 y) pure returns (UD60x18 result) {
    result = wrap(x.unwrap() | y.unwrap());
}

/// @notice Implements the right shift operation (>>) in the UD60x18 type.
function rshift(UD60x18 x, uint256 bits) pure returns (UD60x18 result) {
    result = wrap(x.unwrap() >> bits);
}

/// @notice Implements the checked subtraction operation (-) in the UD60x18 type.
function sub(UD60x18 x, UD60x18 y) pure returns (UD60x18 result) {
    result = wrap(x.unwrap() - y.unwrap());
}

/// @notice Implements the unchecked addition operation (+) in the UD60x18 type.
function uncheckedAdd(UD60x18 x, UD60x18 y) pure returns (UD60x18 result) {
    unchecked {
        result = wrap(x.unwrap() + y.unwrap());
    }
}

/// @notice Implements the unchecked subtraction operation (-) in the UD60x18 type.
function uncheckedSub(UD60x18 x, UD60x18 y) pure returns (UD60x18 result) {
    unchecked {
        result = wrap(x.unwrap() - y.unwrap());
    }
}

/// @notice Implements the XOR (^) bitwise operation in the UD60x18 type.
function xor(UD60x18 x, UD60x18 y) pure returns (UD60x18 result) {
    result = wrap(x.unwrap() ^ y.unwrap());
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @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);

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

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

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^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-3.0-or-later
pragma solidity ^0.8.0;

import {IERC20} from "@openzeppelin/contracts@4.9.3/token/ERC20/IERC20.sol";

/// @notice Principal tokens (zero-coupon tokens) are redeemable for a single underlying EIP-20 token at a future timestamp.
///         https://eips.ethereum.org/EIPS/eip-5095
interface IERC5095 is IERC20 {
    event Redeem(address indexed from, address indexed to, uint256 underlyingAmount);

    /// @dev Asset that is returned on redemption.
    function underlying() external view returns (address underlyingAddress);

    /// @dev Unix time at which redemption of fyToken for underlying are possible
    function maturity() external view returns (uint256 timestamp);

    /// @dev Converts a specified amount of principal to underlying
    function convertToUnderlying(uint256 principalAmount) external view returns (uint256 underlyingAmount);

    /// @dev Converts a specified amount of underlying to principal
    function convertToPrincipal(uint256 underlyingAmount) external view returns (uint256 principalAmount);

    /// @dev Gives the maximum amount an address holder can redeem in terms of the principal
    function maxRedeem(address holder) external view returns (uint256 maxPrincipalAmount);

    /// @dev Gives the amount in terms of underlying that the princiapl amount can be redeemed for plus accrual
    function previewRedeem(uint256 principalAmount) external view returns (uint256 underlyingAmount);

    /// @dev Burn fyToken after maturity for an amount of principal.
    function redeem(uint256 principalAmount, address to, address from) external returns (uint256 underlyingAmount);

    /// @dev Gives the maximum amount an address holder can withdraw in terms of the underlying
    function maxWithdraw(address holder) external view returns (uint256 maxUnderlyingAmount);

    /// @dev Gives the amount in terms of principal that the underlying amount can be withdrawn for plus accrual
    function previewWithdraw(uint256 underlyingAmount) external view returns (uint256 principalAmount);

    /// @dev Burn fyToken after maturity for an amount of underlying.
    function withdraw(uint256 underlyingAmount, address to, address from) external returns (uint256 principalAmount);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (interfaces/IERC5267.sol)

pragma solidity ^0.8.0;

interface IERC5267 {
    /**
     * @dev MAY be emitted to signal that the domain could have changed.
     */
    event EIP712DomainChanged();

    /**
     * @dev returns the fields and values that describe the domain separator used by this contract for EIP-712
     * signature.
     */
    function eip712Domain()
        external
        view
        returns (
            bytes1 fields,
            string memory name,
            string memory version,
            uint256 chainId,
            address verifyingContract,
            bytes32 salt,
            uint256[] memory extensions
        );
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.0;

interface INapierMintCallback {
    /**
     * @notice Callback function to handle the add liquidity.
     * @param underlyingDelta The change in underlying.
     * @param baseLptDelta The change in Base pool LP token.
     * @param data Additional data passed to the callback. Can be used to pass context-specific information.
     */
    function mintCallback(uint256 underlyingDelta, uint256 baseLptDelta, bytes calldata data) external;
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.0;

import {IERC20} from "@openzeppelin/contracts@4.9.3/token/ERC20/IERC20.sol";
import {CurveTricryptoOptimizedWETH} from "./external/CurveTricryptoOptimizedWETH.sol";

import {PoolState} from "../libs/PoolMath.sol";

interface INapierPool {
    event Mint(address indexed receiver, uint256 liquidity, uint256 underlyingUsed, uint256 baseLptUsed);

    event Burn(address indexed receiver, uint256 liquidity, uint256 underlyingOut, uint256 baseLptOut);

    event Swap(
        address indexed caller,
        address indexed receiver,
        int256 netUnderlying,
        uint256 index,
        int256 netPt,
        uint256 swapFee,
        uint256 protocolFee
    );

    event SwapBaseLpt(
        address indexed caller,
        address indexed receiver,
        int256 netUnderlying,
        int256 netBaseLpt,
        uint256 swapFee,
        uint256 protocolFee
    );

    event UpdateLnImpliedRate(uint256 lnImpliedRate);

    /**
     * @notice Add liquidity to the pool with Underlying and base lp token.
     * Caller have to transfer tokens to this contract before calling this function.
     * @param underlyingInDesired The desired amount of underlying asset to add.
     * @param baseLptInDesired The desired amount of base lp token to add.
     * @param recipient The recipient of the liquidity tokens.
     * @param data Additional data for callback.
     * @return The amount of liquidity tokens received.
     */
    function addLiquidity(uint256 underlyingInDesired, uint256 baseLptInDesired, address recipient, bytes memory data)
        external
        returns (uint256);

    /**
     * @notice Remove liquidity from the pool.
     * Caller have to transfer Lp token to this contract before calling this function.
     * @param recipient The recipient of the assets.
     * @return The amounts of base lp token and underlying asset received.
     */
    function removeLiquidity(address recipient) external returns (uint256, uint256);

    /**
     * @notice Swap exact amount of PT for Underlying asset.
     * It supports flash swap by specifying the callback data.
     * Flash swap enables user to receive Underlying asset before paying PT.
     * If the pool contract received enough PT after the callback, the swap is successful. Otherwise, the swap is reverted.
     * @param index The index of the PT.
     * @param ptIn The amount of PT to swap.
     * @param recipient The recipient of the swapped underlying asset.
     * @param data Additional data for the flash swap.
     * @return The amount of underlying asset received.
     */
    function swapPtForUnderlying(uint256 index, uint256 ptIn, address recipient, bytes calldata data)
        external
        returns (uint256);

    /**
     * @notice Swap Underlying asset for exact amount of PT.
     * It supports flash swap by specifying the callback data.
     * It enables user to receive PT before paying Underlying asset.
     * if the pool contract received enough Underlying asset after the callback, the swap is successful. Otherwise, the swap is reverted.
     * @param index The index of the PT.
     * @param ptOut The desired amount of PT to receive.
     * @param recipient The recipient of the PT.
     * @param data Additional data for the flash swap.
     * @return The amount of PT received.
     */
    function swapUnderlyingForPt(uint256 index, uint256 ptOut, address recipient, bytes calldata data)
        external
        returns (uint256);

    /**
     * @notice Swap Underlying asset for exact amount of Base LP token.
     * @param baseLpOut The desired amount of Base LP token to receive.
     * @param recipient The recipient of the Base LP token.
     */
    function swapUnderlyingForExactBaseLpToken(uint256 baseLpOut, address recipient) external returns (uint256);

    /**
     * @notice Swap exact amount of Base LP token for Underlying asset.
     * @param recipient The recipient of the Underlying asset.
     */
    function swapExactBaseLpTokenForUnderlying(uint256 baseLptIn, address recipient) external returns (uint256);

    /**
     * @notice Maturity of the pool, in unix timestamp.
     * @dev Maturity is same as the maturity of Principal Token in the pool.
     */
    function maturity() external view returns (uint256);

    function totalUnderlying() external view returns (uint128);

    function totalBaseLpt() external view returns (uint128);

    function getAssets() external view returns (address, address);

    /**
     * @notice State of the pool.
     * @dev This function is not expected to be called on-chain.
     */
    function readState() external view returns (PoolState memory);

    function tricrypto() external view returns (CurveTricryptoOptimizedWETH);

    function principalTokens() external view returns (IERC20[3] memory);

    function lastLnImpliedRate() external view returns (uint256);
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.0;

interface INapierSwapCallback {
    /**
     * @notice Callback function to handle the token swap.
     * @param underlyingDelta The change in underlying after the swap.
     * @param ptDelta The change in Principal token after the swap.
     * @param data Additional data passed to the callback. Can be used to pass context-specific information.
     */
    function swapCallback(int256 underlyingDelta, int256 ptDelta, bytes calldata data) external;
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.0;

interface IPoolFactory {
    event Deployed(address indexed basePool, address indexed underlying, address indexed pool);
    event AuthorizedCallbackReceiver(address indexed callback);
    event RevokedCallbackReceiver(address indexed callback);

    struct PoolAssets {
        address basePool;
        address underlying;
        address[3] principalTokens;
    }

    struct PoolConfig {
        int256 initialAnchor;
        uint256 scalarRoot;
        uint80 lnFeeRateRoot;
        uint8 protocolFeePercent;
        address feeRecipient;
    }

    struct InitArgs {
        PoolAssets assets;
        PoolConfig configs;
    }

    /// @notice Deploy a new NapierPool contract.
    /// @dev Only the factory owner can call this function.
    /// @param basePool Base pool contract
    /// @param underlying underlying asset
    function deploy(address basePool, address underlying, PoolConfig calldata poolConfig) external returns (address);

    /// @notice Authorize swap callback
    /// @dev Only the factory owner can call this function.
    /// @param callback Callback receiver
    function authorizeCallbackReceiver(address callback) external;

    /// @notice Revoke swap callback authorization
    /// @dev Only the factory owner can call this function.
    /// @param callback Callback receiver
    function revokeCallbackReceiver(address callback) external;

    function isCallbackReceiverAuthorized(address callback) external view returns (bool);

    /// @notice calculate the address of a tranche with CREATE2 using the adapter and maturity as salt
    function poolFor(address basePool, address underlying) external view returns (address);

    /// @param pool a pool address
    /// @dev returns the pool parameters used to deploy the pool
    /// this function doesn't revert even if the pool doesn't exist. It returns the default values in that case.
    /// @return the pool parameters
    function getPoolAssets(address pool) external view returns (PoolAssets memory);

    /// @notice Owner of this contract
    function owner() external view returns (address);

    function args() external view returns (InitArgs memory);

    function POOL_CREATION_HASH() external view returns (bytes32);
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.0;

import {IERC5095} from "./IERC5095.sol";

/// @notice Tranche interface
/// @dev Tranche divides a yield-bearing token into two tokens: Principal and Yield tokens
///      Unspecific types: Simply avoiding dependencies on other interfaces from our interfaces
interface ITranche is IERC5095 {
    /* ==================== ERRORS ===================== */

    error TimestampBeforeMaturity();
    error TimestampAfterMaturity();
    error ProtectedToken();
    error Unauthorized();
    error OnlyYT();
    error ReentrancyGuarded();
    error ZeroAddress();
    error NoAccruedYield();

    /* ==================== EVENTS ===================== */

    /// @param adapter the address of the adapter
    /// @param maturity timestamp of maturity (seconds since Unix epoch)
    /// @param issuanceFee fee for issuing PT and YT
    event SeriesCreated(address indexed adapter, uint256 indexed maturity, uint256 issuanceFee);

    /// @param from the sender of the underlying token
    /// @param to the recipient of the PT and YT
    /// @param underlyingUsed the amount of underlying token used to issue PT and YT
    /// @param sharesUsed the amount of target token used to issue PT and YT (before deducting issuance fee)
    event Issue(address indexed from, address indexed to, uint256 underlyingUsed, uint256 sharesUsed);

    /// @param owner the address of the owner of the PT and YT (address that called collect())
    /// @param shares the amount of Target token collected
    event Collect(address indexed owner, uint256 shares);

    /// @param owner the address of the owner of the PT and YT
    /// @param to the recipient of the underlying token redeemed
    /// @param underlyingRedeemed the amount of underlying token redeemed
    event RedeemWithYT(address indexed owner, address indexed to, uint256 underlyingRedeemed);

    /* ==================== STRUCTS ===================== */

    /// @notice Series is a struct that contains all the information about a series.
    /// @param underlying the address of the underlying token
    /// @param target the address of the target token
    /// @param yt the address of the Yield Token
    /// @param adapter the address of the adapter
    /// @param mscale scale value at maturity
    /// @param maxscale max scale value from this series' lifetime
    /// @param issuanceFee fee for issuing PT and YT
    /// @param maturity timestamp of maturity (seconds since Unix epoch)
    struct Series {
        address underlying;
        address target;
        address yt;
        address adapter;
        uint256 mscale;
        uint256 maxscale;
        uint64 issuanceFee;
        uint64 maturity;
    }

    /// @notice GlobalScales is a struct that contains scale values that are used in multiple functions throughout the Tranche contract.
    /// @param mscale scale value at maturity. before maturity and settlement, this value is 0.
    /// @param maxscale max scale value from this series' lifetime.
    struct GlobalScales {
        uint128 mscale;
        uint128 maxscale;
    }

    /* ================== MUTATIVE METHODS =================== */

    /// @notice deposit an `underlyingAmount` of underlying token into the yield source, receiving PT and YT.
    ///         amount of PT and YT issued are the same.
    /// @param   to the address to receive PT and YT
    /// @param   underlyingAmount the amount of underlying token to deposit
    /// @return  principalAmount the amount of PT and YT issued
    function issue(address to, uint256 underlyingAmount) external returns (uint256 principalAmount);

    /// @notice redeem an `principalAmount` of PT and YT for underlying token.
    /// @param from the address to burn PT and YT from
    /// @param to the address to receive underlying token
    /// @param pyAmount the amount of PT and YT to redeem
    /// @return underlyingAmount the amount of underlying token redeemed
    function redeemWithYT(address from, address to, uint256 pyAmount) external returns (uint256 underlyingAmount);

    /// @notice collect interest for `msg.sender` and transfer accrued interest to `msg.sender`
    /// NOTE: if the maturity has passed, all the YT balance of `msg.sender` is burned.
    /// @dev anyone can call this function to collect interest for themselves
    /// @return collected collected interest in Underlying token
    function collect() external returns (uint256 collected);

    /* ================== PERMISSIONED METHODS =================== */

    /// @notice collect interest from the yield source and distribute it
    ///         every YT transfer, this function is triggered by the Yield Token contract.
    ///         only the Yield Token contract can call this function.
    ///         NOTE: YT is not burned in this function even if the maturity has passed.
    /// @param from address to transfer the Yield Token from. i.e. the user who collects the interest.
    /// @param to address to transfer the Yield Token to (MUST NOT be zero address, CAN be the same as `from`)
    /// @param value amount of Yield Token transferred to `to` (CAN be 0)
    function updateUnclaimedYield(address from, address to, uint256 value) external;

    /* ================== VIEW METHODS =================== */

    /// @notice get the address of Yield Token associated with this Tranche.
    function yieldToken() external view returns (address);

    /// @notice get Series struct
    function getSeries() external view returns (Series memory);

    /// @notice get an accrued yield that can be claimed by `account` (in unis of Target token)
    /// @dev this is reset to 0 when `account` claims the yield.
    /// @param account the address to check
    /// @return accruedInTarget
    function unclaimedYields(address account) external view returns (uint256 accruedInTarget);

    /// @notice get an accrued yield that can be claimed by `account` (in unis of Underlying token)
    /// @param account the address to check
    /// @return accruedInUnderlying accrued yield in underlying token
    function previewCollect(address account) external view returns (uint256 accruedInUnderlying);
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

import "../Common.sol" as Common;
import "./Errors.sol" as Errors;
import {
    uEXP_MAX_INPUT,
    uEXP2_MAX_INPUT,
    uHALF_UNIT,
    uLOG2_10,
    uLOG2_E,
    uMAX_SD59x18,
    uMAX_WHOLE_SD59x18,
    uMIN_SD59x18,
    uMIN_WHOLE_SD59x18,
    UNIT,
    uUNIT,
    uUNIT_SQUARED,
    ZERO
} from "./Constants.sol";
import { wrap } from "./Helpers.sol";
import { SD59x18 } from "./ValueType.sol";

/// @notice Calculates the absolute value of x.
///
/// @dev Requirements:
/// - x must be greater than `MIN_SD59x18`.
///
/// @param x The SD59x18 number for which to calculate the absolute value.
/// @param result The absolute value of x as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function abs(SD59x18 x) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    if (xInt == uMIN_SD59x18) {
        revert Errors.PRBMath_SD59x18_Abs_MinSD59x18();
    }
    result = xInt < 0 ? wrap(-xInt) : x;
}

/// @notice Calculates the arithmetic average of x and y.
///
/// @dev Notes:
/// - The result is rounded toward zero.
///
/// @param x The first operand as an SD59x18 number.
/// @param y The second operand as an SD59x18 number.
/// @return result The arithmetic average as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function avg(SD59x18 x, SD59x18 y) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    int256 yInt = y.unwrap();

    unchecked {
        // This operation is equivalent to `x / 2 +  y / 2`, and it can never overflow.
        int256 sum = (xInt >> 1) + (yInt >> 1);

        if (sum < 0) {
            // If at least one of x and y is odd, add 1 to the result, because shifting negative numbers to the right
            // rounds toward negative infinity. The right part is equivalent to `sum + (x % 2 == 1 || y % 2 == 1)`.
            assembly ("memory-safe") {
                result := add(sum, and(or(xInt, yInt), 1))
            }
        } else {
            // Add 1 if both x and y are odd to account for the double 0.5 remainder truncated after shifting.
            result = wrap(sum + (xInt & yInt & 1));
        }
    }
}

/// @notice Yields the smallest whole number greater than or equal to x.
///
/// @dev Optimized for fractional value inputs, because every whole value has (1e18 - 1) fractional counterparts.
/// See https://en.wikipedia.org/wiki/Floor_and_ceiling_functions.
///
/// Requirements:
/// - x must be less than or equal to `MAX_WHOLE_SD59x18`.
///
/// @param x The SD59x18 number to ceil.
/// @param result The smallest whole number greater than or equal to x, as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function ceil(SD59x18 x) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    if (xInt > uMAX_WHOLE_SD59x18) {
        revert Errors.PRBMath_SD59x18_Ceil_Overflow(x);
    }

    int256 remainder = xInt % uUNIT;
    if (remainder == 0) {
        result = x;
    } else {
        unchecked {
            // Solidity uses C fmod style, which returns a modulus with the same sign as x.
            int256 resultInt = xInt - remainder;
            if (xInt > 0) {
                resultInt += uUNIT;
            }
            result = wrap(resultInt);
        }
    }
}

/// @notice Divides two SD59x18 numbers, returning a new SD59x18 number.
///
/// @dev This is an extension of {Common.mulDiv} for signed numbers, which works by computing the signs and the absolute
/// values separately.
///
/// Notes:
/// - Refer to the notes in {Common.mulDiv}.
/// - The result is rounded toward zero.
///
/// Requirements:
/// - Refer to the requirements in {Common.mulDiv}.
/// - None of the inputs can be `MIN_SD59x18`.
/// - The denominator must not be zero.
/// - The result must fit in SD59x18.
///
/// @param x The numerator as an SD59x18 number.
/// @param y The denominator as an SD59x18 number.
/// @param result The quotient as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function div(SD59x18 x, SD59x18 y) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    int256 yInt = y.unwrap();
    if (xInt == uMIN_SD59x18 || yInt == uMIN_SD59x18) {
        revert Errors.PRBMath_SD59x18_Div_InputTooSmall();
    }

    // Get hold of the absolute values of x and y.
    uint256 xAbs;
    uint256 yAbs;
    unchecked {
        xAbs = xInt < 0 ? uint256(-xInt) : uint256(xInt);
        yAbs = yInt < 0 ? uint256(-yInt) : uint256(yInt);
    }

    // Compute the absolute value (x*UNIT÷y). The resulting value must fit in SD59x18.
    uint256 resultAbs = Common.mulDiv(xAbs, uint256(uUNIT), yAbs);
    if (resultAbs > uint256(uMAX_SD59x18)) {
        revert Errors.PRBMath_SD59x18_Div_Overflow(x, y);
    }

    // Check if x and y have the same sign using two's complement representation. The left-most bit represents the sign (1 for
    // negative, 0 for positive or zero).
    bool sameSign = (xInt ^ yInt) > -1;

    // If the inputs have the same sign, the result should be positive. Otherwise, it should be negative.
    unchecked {
        result = wrap(sameSign ? int256(resultAbs) : -int256(resultAbs));
    }
}

/// @notice Calculates the natural exponent of x using the following formula:
///
/// $$
/// e^x = 2^{x * log_2{e}}
/// $$
///
/// @dev Notes:
/// - Refer to the notes in {exp2}.
///
/// Requirements:
/// - Refer to the requirements in {exp2}.
/// - x must be less than 133_084258667509499441.
///
/// @param x The exponent as an SD59x18 number.
/// @return result The result as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function exp(SD59x18 x) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();

    // This check prevents values greater than 192e18 from being passed to {exp2}.
    if (xInt > uEXP_MAX_INPUT) {
        revert Errors.PRBMath_SD59x18_Exp_InputTooBig(x);
    }

    unchecked {
        // Inline the fixed-point multiplication to save gas.
        int256 doubleUnitProduct = xInt * uLOG2_E;
        result = exp2(wrap(doubleUnitProduct / uUNIT));
    }
}

/// @notice Calculates the binary exponent of x using the binary fraction method using the following formula:
///
/// $$
/// 2^{-x} = \frac{1}{2^x}
/// $$
///
/// @dev See https://ethereum.stackexchange.com/q/79903/24693.
///
/// Notes:
/// - If x is less than -59_794705707972522261, the result is zero.
///
/// Requirements:
/// - x must be less than 192e18.
/// - The result must fit in SD59x18.
///
/// @param x The exponent as an SD59x18 number.
/// @return result The result as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function exp2(SD59x18 x) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    if (xInt < 0) {
        // The inverse of any number less than this is truncated to zero.
        if (xInt < -59_794705707972522261) {
            return ZERO;
        }

        unchecked {
            // Inline the fixed-point inversion to save gas.
            result = wrap(uUNIT_SQUARED / exp2(wrap(-xInt)).unwrap());
        }
    } else {
        // Numbers greater than or equal to 192e18 don't fit in the 192.64-bit format.
        if (xInt > uEXP2_MAX_INPUT) {
            revert Errors.PRBMath_SD59x18_Exp2_InputTooBig(x);
        }

        unchecked {
            // Convert x to the 192.64-bit fixed-point format.
            uint256 x_192x64 = uint256((xInt << 64) / uUNIT);

            // It is safe to cast the result to int256 due to the checks above.
            result = wrap(int256(Common.exp2(x_192x64)));
        }
    }
}

/// @notice Yields the greatest whole number less than or equal to x.
///
/// @dev Optimized for fractional value inputs, because for every whole value there are (1e18 - 1) fractional
/// counterparts. See https://en.wikipedia.org/wiki/Floor_and_ceiling_functions.
///
/// Requirements:
/// - x must be greater than or equal to `MIN_WHOLE_SD59x18`.
///
/// @param x The SD59x18 number to floor.
/// @param result The greatest whole number less than or equal to x, as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function floor(SD59x18 x) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    if (xInt < uMIN_WHOLE_SD59x18) {
        revert Errors.PRBMath_SD59x18_Floor_Underflow(x);
    }

    int256 remainder = xInt % uUNIT;
    if (remainder == 0) {
        result = x;
    } else {
        unchecked {
            // Solidity uses C fmod style, which returns a modulus with the same sign as x.
            int256 resultInt = xInt - remainder;
            if (xInt < 0) {
                resultInt -= uUNIT;
            }
            result = wrap(resultInt);
        }
    }
}

/// @notice Yields the excess beyond the floor of x for positive numbers and the part of the number to the right.
/// of the radix point for negative numbers.
/// @dev Based on the odd function definition. https://en.wikipedia.org/wiki/Fractional_part
/// @param x The SD59x18 number to get the fractional part of.
/// @param result The fractional part of x as an SD59x18 number.
function frac(SD59x18 x) pure returns (SD59x18 result) {
    result = wrap(x.unwrap() % uUNIT);
}

/// @notice Calculates the geometric mean of x and y, i.e. $\sqrt{x * y}$.
///
/// @dev Notes:
/// - The result is rounded toward zero.
///
/// Requirements:
/// - x * y must fit in SD59x18.
/// - x * y must not be negative, since complex numbers are not supported.
///
/// @param x The first operand as an SD59x18 number.
/// @param y The second operand as an SD59x18 number.
/// @return result The result as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function gm(SD59x18 x, SD59x18 y) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    int256 yInt = y.unwrap();
    if (xInt == 0 || yInt == 0) {
        return ZERO;
    }

    unchecked {
        // Equivalent to `xy / x != y`. Checking for overflow this way is faster than letting Solidity do it.
        int256 xyInt = xInt * yInt;
        if (xyInt / xInt != yInt) {
            revert Errors.PRBMath_SD59x18_Gm_Overflow(x, y);
        }

        // The product must not be negative, since complex numbers are not supported.
        if (xyInt < 0) {
            revert Errors.PRBMath_SD59x18_Gm_NegativeProduct(x, y);
        }

        // We don't need to multiply the result by `UNIT` here because the x*y product picked up a factor of `UNIT`
        // during multiplication. See the comments in {Common.sqrt}.
        uint256 resultUint = Common.sqrt(uint256(xyInt));
        result = wrap(int256(resultUint));
    }
}

/// @notice Calculates the inverse of x.
///
/// @dev Notes:
/// - The result is rounded toward zero.
///
/// Requirements:
/// - x must not be zero.
///
/// @param x The SD59x18 number for which to calculate the inverse.
/// @return result The inverse as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function inv(SD59x18 x) pure returns (SD59x18 result) {
    result = wrap(uUNIT_SQUARED / x.unwrap());
}

/// @notice Calculates the natural logarithm of x using the following formula:
///
/// $$
/// ln{x} = log_2{x} / log_2{e}
/// $$
///
/// @dev Notes:
/// - Refer to the notes in {log2}.
/// - The precision isn't sufficiently fine-grained to return exactly `UNIT` when the input is `E`.
///
/// Requirements:
/// - Refer to the requirements in {log2}.
///
/// @param x The SD59x18 number for which to calculate the natural logarithm.
/// @return result The natural logarithm as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function ln(SD59x18 x) pure returns (SD59x18 result) {
    // Inline the fixed-point multiplication to save gas. This is overflow-safe because the maximum value that
    // {log2} can return is ~195_205294292027477728.
    result = wrap(log2(x).unwrap() * uUNIT / uLOG2_E);
}

/// @notice Calculates the common logarithm of x using the following formula:
///
/// $$
/// log_{10}{x} = log_2{x} / log_2{10}
/// $$
///
/// However, if x is an exact power of ten, a hard coded value is returned.
///
/// @dev Notes:
/// - Refer to the notes in {log2}.
///
/// Requirements:
/// - Refer to the requirements in {log2}.
///
/// @param x The SD59x18 number for which to calculate the common logarithm.
/// @return result The common logarithm as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function log10(SD59x18 x) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    if (xInt < 0) {
        revert Errors.PRBMath_SD59x18_Log_InputTooSmall(x);
    }

    // Note that the `mul` in this block is the standard multiplication operation, not {SD59x18.mul}.
    // prettier-ignore
    assembly ("memory-safe") {
        switch x
        case 1 { result := mul(uUNIT, sub(0, 18)) }
        case 10 { result := mul(uUNIT, sub(1, 18)) }
        case 100 { result := mul(uUNIT, sub(2, 18)) }
        case 1000 { result := mul(uUNIT, sub(3, 18)) }
        case 10000 { result := mul(uUNIT, sub(4, 18)) }
        case 100000 { result := mul(uUNIT, sub(5, 18)) }
        case 1000000 { result := mul(uUNIT, sub(6, 18)) }
        case 10000000 { result := mul(uUNIT, sub(7, 18)) }
        case 100000000 { result := mul(uUNIT, sub(8, 18)) }
        case 1000000000 { result := mul(uUNIT, sub(9, 18)) }
        case 10000000000 { result := mul(uUNIT, sub(10, 18)) }
        case 100000000000 { result := mul(uUNIT, sub(11, 18)) }
        case 1000000000000 { result := mul(uUNIT, sub(12, 18)) }
        case 10000000000000 { result := mul(uUNIT, sub(13, 18)) }
        case 100000000000000 { result := mul(uUNIT, sub(14, 18)) }
        case 1000000000000000 { result := mul(uUNIT, sub(15, 18)) }
        case 10000000000000000 { result := mul(uUNIT, sub(16, 18)) }
        case 100000000000000000 { result := mul(uUNIT, sub(17, 18)) }
        case 1000000000000000000 { result := 0 }
        case 10000000000000000000 { result := uUNIT }
        case 100000000000000000000 { result := mul(uUNIT, 2) }
        case 1000000000000000000000 { result := mul(uUNIT, 3) }
        case 10000000000000000000000 { result := mul(uUNIT, 4) }
        case 100000000000000000000000 { result := mul(uUNIT, 5) }
        case 1000000000000000000000000 { result := mul(uUNIT, 6) }
        case 10000000000000000000000000 { result := mul(uUNIT, 7) }
        case 100000000000000000000000000 { result := mul(uUNIT, 8) }
        case 1000000000000000000000000000 { result := mul(uUNIT, 9) }
        case 10000000000000000000000000000 { result := mul(uUNIT, 10) }
        case 100000000000000000000000000000 { result := mul(uUNIT, 11) }
        case 1000000000000000000000000000000 { result := mul(uUNIT, 12) }
        case 10000000000000000000000000000000 { result := mul(uUNIT, 13) }
        case 100000000000000000000000000000000 { result := mul(uUNIT, 14) }
        case 1000000000000000000000000000000000 { result := mul(uUNIT, 15) }
        case 10000000000000000000000000000000000 { result := mul(uUNIT, 16) }
        case 100000000000000000000000000000000000 { result := mul(uUNIT, 17) }
        case 1000000000000000000000000000000000000 { result := mul(uUNIT, 18) }
        case 10000000000000000000000000000000000000 { result := mul(uUNIT, 19) }
        case 100000000000000000000000000000000000000 { result := mul(uUNIT, 20) }
        case 1000000000000000000000000000000000000000 { result := mul(uUNIT, 21) }
        case 10000000000000000000000000000000000000000 { result := mul(uUNIT, 22) }
        case 100000000000000000000000000000000000000000 { result := mul(uUNIT, 23) }
        case 1000000000000000000000000000000000000000000 { result := mul(uUNIT, 24) }
        case 10000000000000000000000000000000000000000000 { result := mul(uUNIT, 25) }
        case 100000000000000000000000000000000000000000000 { result := mul(uUNIT, 26) }
        case 1000000000000000000000000000000000000000000000 { result := mul(uUNIT, 27) }
        case 10000000000000000000000000000000000000000000000 { result := mul(uUNIT, 28) }
        case 100000000000000000000000000000000000000000000000 { result := mul(uUNIT, 29) }
        case 1000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 30) }
        case 10000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 31) }
        case 100000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 32) }
        case 1000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 33) }
        case 10000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 34) }
        case 100000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 35) }
        case 1000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 36) }
        case 10000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 37) }
        case 100000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 38) }
        case 1000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 39) }
        case 10000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 40) }
        case 100000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 41) }
        case 1000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 42) }
        case 10000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 43) }
        case 100000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 44) }
        case 1000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 45) }
        case 10000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 46) }
        case 100000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 47) }
        case 1000000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 48) }
        case 10000000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 49) }
        case 100000000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 50) }
        case 1000000000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 51) }
        case 10000000000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 52) }
        case 100000000000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 53) }
        case 1000000000000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 54) }
        case 10000000000000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 55) }
        case 100000000000000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 56) }
        case 1000000000000000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 57) }
        case 10000000000000000000000000000000000000000000000000000000000000000000000000000 { result := mul(uUNIT, 58) }
        default { result := uMAX_SD59x18 }
    }

    if (result.unwrap() == uMAX_SD59x18) {
        unchecked {
            // Inline the fixed-point division to save gas.
            result = wrap(log2(x).unwrap() * uUNIT / uLOG2_10);
        }
    }
}

/// @notice Calculates the binary logarithm of x using the iterative approximation algorithm:
///
/// $$
/// log_2{x} = n + log_2{y}, \text{ where } y = x*2^{-n}, \ y \in [1, 2)
/// $$
///
/// For $0 \leq x \lt 1$, the input is inverted:
///
/// $$
/// log_2{x} = -log_2{\frac{1}{x}}
/// $$
///
/// @dev See https://en.wikipedia.org/wiki/Binary_logarithm#Iterative_approximation.
///
/// Notes:
/// - Due to the lossy precision of the iterative approximation, the results are not perfectly accurate to the last decimal.
///
/// Requirements:
/// - x must be greater than zero.
///
/// @param x The SD59x18 number for which to calculate the binary logarithm.
/// @return result The binary logarithm as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function log2(SD59x18 x) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    if (xInt <= 0) {
        revert Errors.PRBMath_SD59x18_Log_InputTooSmall(x);
    }

    unchecked {
        int256 sign;
        if (xInt >= uUNIT) {
            sign = 1;
        } else {
            sign = -1;
            // Inline the fixed-point inversion to save gas.
            xInt = uUNIT_SQUARED / xInt;
        }

        // Calculate the integer part of the logarithm.
        uint256 n = Common.msb(uint256(xInt / uUNIT));

        // This is the integer part of the logarithm as an SD59x18 number. The operation can't overflow
        // because n is at most 255, `UNIT` is 1e18, and the sign is either 1 or -1.
        int256 resultInt = int256(n) * uUNIT;

        // Calculate $y = x * 2^{-n}$.
        int256 y = xInt >> n;

        // If y is the unit number, the fractional part is zero.
        if (y == uUNIT) {
            return wrap(resultInt * sign);
        }

        // Calculate the fractional part via the iterative approximation.
        // The `delta >>= 1` part is equivalent to `delta /= 2`, but shifting bits is more gas efficient.
        int256 DOUBLE_UNIT = 2e18;
        for (int256 delta = uHALF_UNIT; delta > 0; delta >>= 1) {
            y = (y * y) / uUNIT;

            // Is y^2 >= 2e18 and so in the range [2e18, 4e18)?
            if (y >= DOUBLE_UNIT) {
                // Add the 2^{-m} factor to the logarithm.
                resultInt = resultInt + delta;

                // Halve y, which corresponds to z/2 in the Wikipedia article.
                y >>= 1;
            }
        }
        resultInt *= sign;
        result = wrap(resultInt);
    }
}

/// @notice Multiplies two SD59x18 numbers together, returning a new SD59x18 number.
///
/// @dev Notes:
/// - Refer to the notes in {Common.mulDiv18}.
///
/// Requirements:
/// - Refer to the requirements in {Common.mulDiv18}.
/// - None of the inputs can be `MIN_SD59x18`.
/// - The result must fit in SD59x18.
///
/// @param x The multiplicand as an SD59x18 number.
/// @param y The multiplier as an SD59x18 number.
/// @return result The product as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function mul(SD59x18 x, SD59x18 y) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    int256 yInt = y.unwrap();
    if (xInt == uMIN_SD59x18 || yInt == uMIN_SD59x18) {
        revert Errors.PRBMath_SD59x18_Mul_InputTooSmall();
    }

    // Get hold of the absolute values of x and y.
    uint256 xAbs;
    uint256 yAbs;
    unchecked {
        xAbs = xInt < 0 ? uint256(-xInt) : uint256(xInt);
        yAbs = yInt < 0 ? uint256(-yInt) : uint256(yInt);
    }

    // Compute the absolute value (x*y÷UNIT). The resulting value must fit in SD59x18.
    uint256 resultAbs = Common.mulDiv18(xAbs, yAbs);
    if (resultAbs > uint256(uMAX_SD59x18)) {
        revert Errors.PRBMath_SD59x18_Mul_Overflow(x, y);
    }

    // Check if x and y have the same sign using two's complement representation. The left-most bit represents the sign (1 for
    // negative, 0 for positive or zero).
    bool sameSign = (xInt ^ yInt) > -1;

    // If the inputs have the same sign, the result should be positive. Otherwise, it should be negative.
    unchecked {
        result = wrap(sameSign ? int256(resultAbs) : -int256(resultAbs));
    }
}

/// @notice Raises x to the power of y using the following formula:
///
/// $$
/// x^y = 2^{log_2{x} * y}
/// $$
///
/// @dev Notes:
/// - Refer to the notes in {exp2}, {log2}, and {mul}.
/// - Returns `UNIT` for 0^0.
///
/// Requirements:
/// - Refer to the requirements in {exp2}, {log2}, and {mul}.
///
/// @param x The base as an SD59x18 number.
/// @param y Exponent to raise x to, as an SD59x18 number
/// @return result x raised to power y, as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function pow(SD59x18 x, SD59x18 y) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    int256 yInt = y.unwrap();

    // If both x and y are zero, the result is `UNIT`. If just x is zero, the result is always zero.
    if (xInt == 0) {
        return yInt == 0 ? UNIT : ZERO;
    }
    // If x is `UNIT`, the result is always `UNIT`.
    else if (xInt == uUNIT) {
        return UNIT;
    }

    // If y is zero, the result is always `UNIT`.
    if (yInt == 0) {
        return UNIT;
    }
    // If y is `UNIT`, the result is always x.
    else if (yInt == uUNIT) {
        return x;
    }

    // Calculate the result using the formula.
    result = exp2(mul(log2(x), y));
}

/// @notice Raises x (an SD59x18 number) to the power y (an unsigned basic integer) using the well-known
/// algorithm "exponentiation by squaring".
///
/// @dev See https://en.wikipedia.org/wiki/Exponentiation_by_squaring.
///
/// Notes:
/// - Refer to the notes in {Common.mulDiv18}.
/// - Returns `UNIT` for 0^0.
///
/// Requirements:
/// - Refer to the requirements in {abs} and {Common.mulDiv18}.
/// - The result must fit in SD59x18.
///
/// @param x The base as an SD59x18 number.
/// @param y The exponent as a uint256.
/// @return result The result as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function powu(SD59x18 x, uint256 y) pure returns (SD59x18 result) {
    uint256 xAbs = uint256(abs(x).unwrap());

    // Calculate the first iteration of the loop in advance.
    uint256 resultAbs = y & 1 > 0 ? xAbs : uint256(uUNIT);

    // Equivalent to `for(y /= 2; y > 0; y /= 2)`.
    uint256 yAux = y;
    for (yAux >>= 1; yAux > 0; yAux >>= 1) {
        xAbs = Common.mulDiv18(xAbs, xAbs);

        // Equivalent to `y % 2 == 1`.
        if (yAux & 1 > 0) {
            resultAbs = Common.mulDiv18(resultAbs, xAbs);
        }
    }

    // The result must fit in SD59x18.
    if (resultAbs > uint256(uMAX_SD59x18)) {
        revert Errors.PRBMath_SD59x18_Powu_Overflow(x, y);
    }

    unchecked {
        // Is the base negative and the exponent odd? If yes, the result should be negative.
        int256 resultInt = int256(resultAbs);
        bool isNegative = x.unwrap() < 0 && y & 1 == 1;
        if (isNegative) {
            resultInt = -resultInt;
        }
        result = wrap(resultInt);
    }
}

/// @notice Calculates the square root of x using the Babylonian method.
///
/// @dev See https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method.
///
/// Notes:
/// - Only the positive root is returned.
/// - The result is rounded toward zero.
///
/// Requirements:
/// - x cannot be negative, since complex numbers are not supported.
/// - x must be less than `MAX_SD59x18 / UNIT`.
///
/// @param x The SD59x18 number for which to calculate the square root.
/// @return result The result as an SD59x18 number.
/// @custom:smtchecker abstract-function-nondet
function sqrt(SD59x18 x) pure returns (SD59x18 result) {
    int256 xInt = x.unwrap();
    if (xInt < 0) {
        revert Errors.PRBMath_SD59x18_Sqrt_NegativeInput(x);
    }
    if (xInt > uMAX_SD59x18 / uUNIT) {
        revert Errors.PRBMath_SD59x18_Sqrt_Overflow(x);
    }

    unchecked {
        // Multiply x by `UNIT` to account for the factor of `UNIT` picked up when multiplying two SD59x18 numbers.
        // In this case, the two numbers are both the square root.
        uint256 resultUint = Common.sqrt(uint256(xInt * uUNIT));
        result = wrap(int256(resultUint));
    }
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.19;

// interfaces
import {IERC20} from "@openzeppelin/contracts@4.9.3/token/ERC20/IERC20.sol";
import {ITranche} from "@napier/v1-tranche/src/interfaces/ITranche.sol";
import {CurveTricryptoOptimizedWETH} from "./interfaces/external/CurveTricryptoOptimizedWETH.sol";

import {INapierPool} from "./interfaces/INapierPool.sol";
import {INapierSwapCallback} from "./interfaces/INapierSwapCallback.sol";
import {INapierMintCallback} from "./interfaces/INapierMintCallback.sol";
import {IPoolFactory} from "./interfaces/IPoolFactory.sol";
// libs
import {SafeCast} from "@openzeppelin/contracts@4.9.3/utils/math/SafeCast.sol";
import {SafeERC20} from "@openzeppelin/contracts@4.9.3/token/ERC20/utils/SafeERC20.sol";
import {Math} from "@openzeppelin/contracts@4.9.3/utils/math/Math.sol";
import {PoolMath, PoolState} from "./libs/PoolMath.sol";
import {SignedMath} from "./libs/SignedMath.sol";
import {DecimalConversion} from "./libs/DecimalConversion.sol";
import {MAX_LN_FEE_RATE_ROOT, MAX_PROTOCOL_FEE_PERCENT} from "./libs/Constants.sol";
import {Errors} from "./libs/Errors.sol";
// inherits
import {ERC20} from "@openzeppelin/contracts@4.9.3/token/ERC20/ERC20.sol";
import {ERC20Permit} from "@openzeppelin/contracts@4.9.3/token/ERC20/extensions/ERC20Permit.sol";
import {ReentrancyGuard} from "@openzeppelin/contracts@4.9.3/security/ReentrancyGuard.sol";

/// @dev NapierPool is a pool that allows users to trade between a BasePool LP token and an underlying asset.
/// BasePool LP token is a token that represents a share of basket of 3 Principal Tokens Curve V2 pool.
///
/// Note: This pool and its math assumes the following regarding BasePool:
/// 1. The BasePool assets are 3 Napier Principal Tokens (PT) of the same maturity and same underlying asset.
///    We can consider BasePool LP token as something like ETF of 3 PTs.
/// 2. BasePool LP token is approximately three times more valuable than 1 PT because the initial deposit on Curve pool issues 1:1:1:1=pt1:pt2:pt3:share.
/// e.g. When the initial price of PT1, PT2 and PT3 is 1,`1` BasePool LP token is convertible to `1` PT1 + `1` PT2 + `1` PT3 instead of `1/3` for each PT.
/// We need to adjust the balance of BasePool LP token by multiplying 3 to make it comparable to underlying asset.
/// Economically at maturity 1/3 BaseLP token is expected to be convertible to approximately 1 underlying asset.
/// 3. BasePool LP token has 18 decimals.
/// 4. PTs have the same decimals as underlying asset.
contract NapierPool is INapierPool, ReentrancyGuard, ERC20Permit {
    using PoolMath for PoolState;
    using SafeERC20 for IERC20;
    using SafeERC20 for CurveTricryptoOptimizedWETH;
    using SignedMath for uint256;
    using SafeCast for uint256;
    using DecimalConversion for uint256;

    uint256 internal constant WAD = 1e18;

    /// @dev Number of coins in the BasePool
    uint256 internal constant N_COINS = 3;

    /// @notice The factory that deployed this pool.
    IPoolFactory public immutable factory;

    /// @notice BasePool LP token i.e. Curve v2 3assets pool
    CurveTricryptoOptimizedWETH public immutable tricrypto;

    /// @notice Underlying asset (e.g. DAI, WETH)
    IERC20 public immutable underlying;
    uint8 internal immutable uDecimals;

    /// @notice Napier Principal Tokens
    /// @dev We don't use static size array here because Solidity doesn't support immutable static size array.
    /// @dev This would significantly reduce gas cost by avoiding SLOAD. About 2000 gas per reading principal token. (cold)
    /// @dev pt_i is the i-th asset of the BasePool coins. i.e pt[i] = CurveV2Pool.coins(i)
    IERC20 internal immutable pt1;
    IERC20 internal immutable pt2;
    IERC20 internal immutable pt3;

    /// @notice Maturity of the pool in unix timestamp
    /// @notice At or after maturity, the pool will no longer accept any liquidity provision or swap. Removing liquidity is still allowed.
    /// @dev Users can still swap, add or remove liquidity even after maturity on Curve pool.
    /// @dev expiry of the pool. This is the maturity of all principal tokens in the pool.
    uint256 public immutable maturity;

    /// @notice AMM parameter: Scalar root of the pool
    /// @dev adjust the capital efficiency of the market.
    uint256 public immutable scalarRoot;

    /// @notice AMM parameter: Initial anchor of the pool
    /// @dev initial rate anchor to anchor the market’s formula to be more capital efficient around a certain interest rate.
    int256 public immutable initialAnchor;

    /// @notice Recipient of the protocol fee
    address public immutable feeRecipient;

    /// @notice AMM parameter: Logarithmic fee rate root of the pool
    /// @dev Fees rate in terms of interest rate
    uint80 internal lnFeeRateRoot;

    /// @notice AMM parameter: Fee Napier charges for swaps in percentage (100=100%)
    uint8 internal protocolFeePercent;

    /// @notice AMM parameter: Last logarithmic implied rate of the pool
    uint256 public lastLnImpliedRate;

    /// @notice Total amount of BaseLpt in the pool (Reserve)
    uint128 public totalBaseLpt;

    /// @notice Total amount of underlying in the pool (Reserve)
    uint128 public totalUnderlying;

    /// @dev Revert if maturity is reached
    modifier notExpired() {
        if (maturity <= block.timestamp) revert Errors.PoolExpired();
        _;
    }

    constructor() payable ERC20("Napier Pool LP Token", "NapierPool LPT") ERC20Permit("Napier Pool LP Token") {
        factory = IPoolFactory(msg.sender);
        IPoolFactory.InitArgs memory args = factory.args();
        // Set mutable variables
        protocolFeePercent = args.configs.protocolFeePercent;
        // Set immutable variables
        scalarRoot = args.configs.scalarRoot;
        initialAnchor = args.configs.initialAnchor;
        lnFeeRateRoot = args.configs.lnFeeRateRoot;
        feeRecipient = args.configs.feeRecipient;

        address basePool = args.assets.basePool;
        tricrypto = CurveTricryptoOptimizedWETH(basePool);

        ERC20 _underlying = ERC20(args.assets.underlying);
        underlying = _underlying;
        uDecimals = _underlying.decimals();

        // hack: we don't use static size array here to save gas cost
        ITranche _pt1 = ITranche(args.assets.principalTokens[0]);
        ITranche _pt2 = ITranche(args.assets.principalTokens[1]);
        ITranche _pt3 = ITranche(args.assets.principalTokens[2]);

        pt1 = _pt1;
        pt2 = _pt2;
        pt3 = _pt3;
        // Assume that the maturity of all principal tokens are the same
        maturity = _pt1.maturity();

        // Approve Curve pool to transfer PTs
        _pt1.approve(basePool, type(uint256).max); // dev: Principal token will revert if failed to approve
        _pt2.approve(basePool, type(uint256).max);
        _pt3.approve(basePool, type(uint256).max);
    }

    ////////////////////////////////////////////////////////////////////////////////
    // Mutative functions
    ////////////////////////////////////////////////////////////////////////////////

    /// @inheritdoc INapierPool
    /// @notice Provide BasePoolLpToken (BaseLpt) and underlying in exchange for Lp token, which will grant LP holders more exchange fee over time
    /// @dev Mint as much LP token as possible.
    /// @dev BaseLpt and Underlying should be transferred to this contract prior to calling
    /// @dev Revert if maturity is reached
    /// @dev Revert if deposited assets are too small to mint more than minimum liquidity
    /// @dev Revert if deposited assets are too small to compute ln implied rate
    /// @dev Revert if computed initial exchange rate in base LP token is below one. (deposited base LP token is much less than deposited underlying)
    /// @dev Revert if proportion of deposited base LP token is higher than the maximum proportion. (deposited base LP token is too large compared to deposited underlying)
    /// @dev Revert if minted LP token is zero
    /// @param recipient recipient of the minted LP token
    /// @return liquidity amount of LP token minted
    function addLiquidity(uint256 underlyingInDesired, uint256 baseLptInDesired, address recipient, bytes memory data)
        external
        override
        nonReentrant
        notExpired
        returns (uint256)
    {
        // Cache state variables
        (uint256 _totalUnderlying, uint256 _totalBaseLpt) = (totalUnderlying, totalBaseLpt);

        uint256 bBalance = _balance(tricrypto); // Base Pool LP token reserve
        uint256 uBalance = _balance(underlying); // NOTE: Sum of underlying asset reserve and stuck protocol fees.

        (uint256 liquidity, uint256 underlyingUsed, uint256 baseLptUsed) =
            _mintLiquidity(_totalUnderlying, _totalBaseLpt, recipient, underlyingInDesired, baseLptInDesired);

        /// WRITE ///
        // Last ln implied rate doesn't change because liquidity is added proportionally
        totalUnderlying = (_totalUnderlying + underlyingUsed).toUint128();
        totalBaseLpt = (_totalBaseLpt + baseLptUsed).toUint128();

        /// INTERACTION ///
        if (!factory.isCallbackReceiverAuthorized(msg.sender)) revert Errors.PoolUnauthorizedCallback();
        INapierMintCallback(msg.sender).mintCallback(underlyingUsed, baseLptUsed, data);

        /// CHECK ///
        if (_balance(tricrypto) < bBalance + baseLptUsed) revert Errors.PoolInsufficientBaseLptReceived();
        if (_balance(underlying) < uBalance + underlyingUsed) {
            revert Errors.PoolInsufficientUnderlyingReceived();
        }

        return liquidity;
    }

    /// @notice Mint LP token for the given amount of underlying and base LP token
    /// @dev This function doesn't update state variables except Lp token and last implied rate.
    /// @dev *variableName*18 represents the value *in 18 decimals*.
    /// @dev Mint as much LP token as possible.
    /// @dev If the pool is not initialized, a portion of issued LP token will be permanently locked.
    /// @dev Revert if minted LP token is zero
    /// @param totalUnderlyingCache total underlying balance of the pool in underlying unit.
    /// @param totalBaseLptCache total base LP token balance of the pool **(All BaseLpt has 18 decimals)**
    /// @param recipient recipient of the minted LP token
    /// @param underlyingIn deposited underlying **in underlying unit**
    /// @param baseLptIn deposited base LP token **(All BaseLpt has 18 decimals)**
    /// @return liquidity - amount of LP token minted
    /// @return underlyingUsed - amount of underlying used
    /// @return baseLptUsed - amount of base LP token used
    function _mintLiquidity(
        uint256 totalUnderlyingCache,
        uint256 totalBaseLptCache,
        address recipient,
        uint256 underlyingIn,
        uint256 baseLptIn
    ) internal returns (uint256 liquidity, uint256 underlyingUsed, uint256 baseLptUsed) {
        uint256 totalLp = totalSupply();

        if (totalLp == 0) {
            // Note: This path is executed only once.
            // Amounts of underlying is converted to 18 decimals to normalize how much LP token is issued.
            liquidity = Math.sqrt(underlyingIn.to18Decimals(uDecimals) * baseLptIn) - PoolMath.MINIMUM_LIQUIDITY;
            underlyingUsed = underlyingIn;
            baseLptUsed = baseLptIn;
            /// WRITE
            // Note: Only at initial issuance, a portion of the issued LP tokens will be permanently locked.
            uint256 virtualPrice = tricrypto.get_virtual_price();
            _mint(address(1), PoolMath.MINIMUM_LIQUIDITY);
            lastLnImpliedRate = PoolMath.computeInitialLnImpliedRate(
                PoolState({
                    totalBaseLptTimesN: baseLptUsed * N_COINS * virtualPrice / WAD,
                    totalUnderlying18: underlyingUsed.to18Decimals(uDecimals),
                    virtualPrice: virtualPrice,
                    scalarRoot: scalarRoot,
                    maturity: maturity,
                    lnFeeRateRoot: lnFeeRateRoot,
                    protocolFeePercent: protocolFeePercent,
                    lastLnImpliedRate: 0
                }),
                initialAnchor
            );
            emit UpdateLnImpliedRate(lastLnImpliedRate);
        } else {
            // Note: Multiplying `N_COINS * virtual_price` is not needed because it is canceled out thanks to ratio calculation.
            uint256 netLpByBaseLpt = (baseLptIn * totalLp) / totalBaseLptCache;
            uint256 netLpByUnderlying = (underlyingIn * totalLp) / totalUnderlyingCache;
            if (netLpByBaseLpt < netLpByUnderlying) {
                liquidity = netLpByBaseLpt;
                baseLptUsed = baseLptIn;
                underlyingUsed = (totalUnderlyingCache * liquidity) / totalLp;
            } else {
                liquidity = netLpByUnderlying;
                underlyingUsed = underlyingIn;
                baseLptUsed = (totalBaseLptCache * liquidity) / totalLp;
            }
        }
        /// WRITE
        // Mint LP token to recipient
        if (liquidity == 0) revert Errors.PoolZeroAmountsOutput();
        _mint(recipient, liquidity);

        emit Mint(recipient, liquidity, underlyingUsed, baseLptUsed);
    }

    /// @inheritdoc INapierPool
    /// @notice Burn Lp token in exchange for underlying and base LP token.
    /// @dev liquidity token (Lp token) should be transferred to this contract prior to calling this function
    /// @dev Revert if underlying and base LP token are zero
    /// @dev Revert if liquidity to burn is zero
    /// @param recipient recipient of the withdrawn underlying and base LP token
    /// @return underlyingOut amount of underlying withdrawn
    /// @return baseLptOut amount of base LP token withdrawn
    function removeLiquidity(address recipient)
        external
        override
        nonReentrant
        returns (uint256 underlyingOut, uint256 baseLptOut)
    {
        uint256 liquidity = balanceOf(address(this));
        (uint256 _totalUnderlying, uint256 _totalBaseLpt) = (totalUnderlying, totalBaseLpt);

        (underlyingOut, baseLptOut) = _burnLiquidity(totalUnderlying, totalBaseLpt, liquidity);
        if (underlyingOut == 0 && baseLptOut == 0) revert Errors.PoolZeroAmountsOutput();

        /// WRITE ///
        totalUnderlying = (_totalUnderlying - underlyingOut).toUint128();
        totalBaseLpt = (_totalBaseLpt - baseLptOut).toUint128();

        /// INTERACTION ///
        underlying.safeTransfer(recipient, underlyingOut);
        tricrypto.safeTransfer(recipient, baseLptOut);

        emit Burn(recipient, liquidity, underlyingOut, baseLptOut);
    }

    /// @notice Burn Lp token in exchange for underlying and Base LP token.
    /// @dev This function doesn't update state variables except Lp token.
    /// @dev *variableName*18 represents the value *in 18 decimals*.
    /// @dev Not revert even if `underlyingOut18` and `baseLptOut` are zero
    /// @param totalUnderlyingCache total underlying balance of the pool **in 18 decimals**.
    /// @param totalBaseLptCache total Base LP token balance of the pool **(All BaseLpt has 18 decimals)**
    /// @param liquidity amount of LP token to burn
    /// @return underlyingOut - amount of underlying withdrawn **in 18 decimals**
    /// @return baseLptOut - amount of Base LP token withdrawn
    function _burnLiquidity(uint256 totalUnderlyingCache, uint256 totalBaseLptCache, uint256 liquidity)
        internal
        returns (uint256 underlyingOut, uint256 baseLptOut)
    {
        if (liquidity == 0) revert Errors.PoolZeroAmountsInput();

        uint256 totalLp = totalSupply();
        underlyingOut = (liquidity * totalUnderlyingCache) / totalLp;
        baseLptOut = (liquidity * totalBaseLptCache) / totalLp;

        _burn(address(this), liquidity);
    }

    /// @inheritdoc INapierPool
    /// @notice Swap exact amount of PT for underlying token
    /// @dev Revert if maturity is reached
    /// @dev Revert if index is invalid
    /// @dev Revert if callback recipient is not authorized
    /// @dev Revert if ptIn is too large and runs out of underlying reserve
    /// @dev Revert if minted base Lp token is less than expected. (pt is not enough to mint expected base Lp token amount)
    /// @param index index of the PT token
    /// @param ptIn amount of PT token to swap
    /// @param recipient recipient of the underlying token and receiver of callback function
    /// @param data data to pass to the recipient on callback. If empty, no callback.
    /// @return underlyingOut amount of underlying token out
    function swapPtForUnderlying(uint256 index, uint256 ptIn, address recipient, bytes calldata data)
        external
        override
        nonReentrant
        notExpired
        returns (uint256 underlyingOut)
    {
        uint256[3] memory amountsIn;
        uint256 exactBaseLptIn;
        uint256 swapFee;
        uint256 protocolFee;
        // stack too deep
        {
            PoolState memory state = _loadState();

            // Pre-compute the swap result given principal token
            amountsIn[index] = ptIn;
            exactBaseLptIn = tricrypto.calc_token_amount(amountsIn, true);
            // Pre-compute the swap result given BaseLpt and underlying
            (uint256 underlyingOut18, uint256 swapFee18, uint256 protocolFee18) =
                state.swapExactBaseLpTokenForUnderlying(exactBaseLptIn);
            underlyingOut = underlyingOut18.from18Decimals(uDecimals);
            swapFee = swapFee18.from18Decimals(uDecimals);
            protocolFee = protocolFee18.from18Decimals(uDecimals);

            // dev: If `underlyingOut18` is less than 10**(18 - underlyingDecimals), `underlyingOut` will be zero.
            // Revert to prevent users from swapping non-zero amount of BaseLpt for 0 underlying.
            if (underlyingOut == 0) revert Errors.PoolZeroAmountsOutput();

            /// WRITE ///
            _writeState(state);
        }
        {
            uint256 bBalance = _balance(tricrypto); // Base Pool LP token reserve
            uint256 uBalance = _balance(underlying); // NOTE: Sum of underlying asset reserve and stuck protocol fees.

            /// INTERACTION ///
            // dev: Optimistically transfer underlying to recipient
            underlying.safeTransfer(recipient, underlyingOut);

            // incoming to user => positive, outgoing from user => negative
            if (!factory.isCallbackReceiverAuthorized(msg.sender)) revert Errors.PoolUnauthorizedCallback();
            INapierSwapCallback(msg.sender).swapCallback(underlyingOut.toInt256(), ptIn.neg(), data);

            // Curve pool will revert if we don't receive enough principal token at this point
            // Deposit the principal token which `msg.sender` should send in the callback to BasePool
            tricrypto.add_liquidity(amountsIn, 0); // unlimited slippage

            /// CHECK ///
            // Revert if we don't receive enough baseLpt
            if (_balance(tricrypto) < bBalance + exactBaseLptIn) revert Errors.PoolInsufficientBaseLptReceived();
            if (_balance(underlying) < uBalance - underlyingOut) {
                revert Errors.PoolInvariantViolated();
            }
        }
        emit Swap(msg.sender, recipient, underlyingOut.toInt256(), index, ptIn.neg(), swapFee, protocolFee);
    }

    /// @inheritdoc INapierPool
    /// @notice Swap underlying token for approximately exact amount of PT
    /// @notice This function can NOT swap underlying for *exact* amount of PT due to approximation error on Curve pool.
    /// Revert if maturity is reached
    /// Revert if index is invalid
    /// Revert if callback recipient is not authorized
    /// Revert if ptOutDesired is too large and runs out of pt reserve in Base pool
    /// Revert if underlying received is less than expected.
    /// @param index index of the PT
    /// @param ptOutDesired amount of PT to be swapped out
    /// @param recipient recipient of the PT and receiver of callback function
    /// @param data data to pass to the recipient on callback
    /// callback can be invoked by only authorized contract
    function swapUnderlyingForPt(uint256 index, uint256 ptOutDesired, address recipient, bytes calldata data)
        external
        override
        nonReentrant
        notExpired
        returns (uint256 underlyingIn)
    {
        uint256 exactBaseLptOut;
        uint256 swapFee;
        uint256 protocolFee;
        // Pre-compute the swap result
        // stack too deep
        {
            PoolState memory state = _loadState();

            uint256[3] memory ptsOut;
            ptsOut[index] = ptOutDesired;
            exactBaseLptOut = tricrypto.calc_token_amount(ptsOut, false);
            // Pre-compute the swap result given BaseLpt
            (uint256 underlyingIn18, uint256 swapFee18, uint256 protocolFee18) =
                state.swapUnderlyingForExactBaseLpToken(exactBaseLptOut);
            underlyingIn = underlyingIn18.from18Decimals(uDecimals);
            swapFee = swapFee18.from18Decimals(uDecimals);
            protocolFee = protocolFee18.from18Decimals(uDecimals);

            // dev: If `underlyingIn18` is less than 10**(18 - underlyingDecimals), `underlyingIn` will be zero.
            // Revert to prevent users from swapping for free.
            if (underlyingIn == 0) revert Errors.PoolZeroAmountsInput();

            /// WRITE ///
            _writeState(state);
        }

        uint256 bBalance = _balance(tricrypto); // Base Pool LP token reserve
        uint256 uBalance = _balance(underlying); // NOTE: Sum of underlying asset reserve and stuck protocol fees.

        /// INTERACTION ///
        // Remove the principal token from BasePool with minimum = 0
        uint256 ptOutActual = tricrypto.remove_liquidity_one_coin(exactBaseLptOut, index, 0, false, recipient);

        // incoming to user => positive, outgoing from user => negative
        if (!factory.isCallbackReceiverAuthorized(msg.sender)) revert Errors.PoolUnauthorizedCallback();
        INapierSwapCallback(msg.sender).swapCallback(underlyingIn.neg(), ptOutActual.toInt256(), data);

        /// CHECK ///
        // Revert if we don't receive enough underlying
        if (_balance(underlying) < uBalance + underlyingIn) {
            revert Errors.PoolInsufficientUnderlyingReceived();
        }
        if (_balance(tricrypto) < bBalance - exactBaseLptOut) {
            revert Errors.PoolInvariantViolated();
        }

        emit Swap(msg.sender, recipient, underlyingIn.neg(), index, ptOutActual.toInt256(), swapFee, protocolFee);
    }

    /// @inheritdoc INapierPool
    /// @notice Swap underlying token for exact amount of Base Lp token
    /// @notice Approve this contract to use underlying prior to calling this function.
    /// @dev Revert if maturity is reached
    function swapUnderlyingForExactBaseLpToken(uint256 baseLptOut, address recipient)
        external
        override
        nonReentrant
        notExpired
        returns (uint256)
    {
        PoolState memory state = _loadState();

        (uint256 underlyingIn18, uint256 swapFee18, uint256 protocolFee18) =
            state.swapUnderlyingForExactBaseLpToken(baseLptOut);
        uint256 underlyingIn = underlyingIn18.from18Decimals(uDecimals);
        uint256 swapFee = swapFee18.from18Decimals(uDecimals);
        uint256 protocolFee = protocolFee18.from18Decimals(uDecimals);

        // dev: If `underlyingIn18` is less than 10**(18 - underlyingDecimals), `underlyingIn` will be zero.
        // Revert to prevent users from swapping for free.
        if (underlyingIn == 0) revert Errors.PoolZeroAmountsInput();

        /// WRITE ///
        _writeState(state);

        /// INTERACTION ///
        underlying.safeTransferFrom(msg.sender, address(this), underlyingIn);
        tricrypto.safeTransfer(recipient, baseLptOut);

        emit SwapBaseLpt(msg.sender, recipient, -(underlyingIn.toInt256()), baseLptOut.toInt256(), swapFee, protocolFee);
        return underlyingIn;
    }

    /// @inheritdoc INapierPool
    /// @notice Swap exact amount of Base Lp token for underlying token
    /// @notice Approve this contract to use BaseLP token prior to calling this function.
    /// @dev Revert if maturity is reached
    function swapExactBaseLpTokenForUnderlying(uint256 baseLptIn, address recipient)
        external
        override
        nonReentrant
        notExpired
        returns (uint256)
    {
        PoolState memory state = _loadState();

        (uint256 underlyingOut18, uint256 swapFee18, uint256 protocolFee18) =
            state.swapExactBaseLpTokenForUnderlying(baseLptIn);
        uint256 underlyingOut = underlyingOut18.from18Decimals(uDecimals);
        uint256 swapFee = swapFee18.from18Decimals(uDecimals);
        uint256 protocolFee = protocolFee18.from18Decimals(uDecimals);

        // dev: If `underlyingOut18` is less than 10**(18 - underlyingDecimals), `underlyingOut` will be zero.
        // Revert to prevent users from swapping non-zero amount of BaseLpt for 0 underlying.
        if (underlyingOut == 0) revert Errors.PoolZeroAmountsOutput();

        /// WRITE ///
        _writeState(state);

        /// INTERACTION ///
        tricrypto.safeTransferFrom(msg.sender, address(this), baseLptIn);
        underlying.safeTransfer(recipient, underlyingOut);

        emit SwapBaseLpt(msg.sender, recipient, underlyingOut.toInt256(), baseLptIn.neg(), swapFee, protocolFee);
        return underlyingOut;
    }

    /// @notice Forcibly sweep excess tokens to the fee recipient
    /// @notice This function can be called by anyone
    /// @notice Protocol fee is sent to the fee recipient
    /// @dev Excess tokens (excluding fees) can be swept by anyone, using `addLiquidity` etc.
    /// @dev Can be used when the pool is in an inconsistent state:
    /// A large amount of base LP token or underlying is donated to the pool, which makes the pool revert when swapping base LP token for underlying
    /// because the pool doesn't have enough underlying to swap.
    function skim() external nonReentrant {
        (uint256 _totalUnderlying, uint256 _totalBaseLpt) = (totalUnderlying, totalBaseLpt);

        uint256 baseLptExcess = _balance(tricrypto) - _totalBaseLpt;
        uint256 feesAndExcess = _balance(underlying) - _totalUnderlying;

        if (baseLptExcess != 0) tricrypto.safeTransfer(feeRecipient, baseLptExcess);
        if (feesAndExcess != 0) underlying.safeTransfer(feeRecipient, feesAndExcess);
    }

    ////////////////////////////////////////////////////////////////////////////////
    // Protected functions
    ////////////////////////////////////////////////////////////////////////////////

    /// @notice Set fee parameters
    /// @notice Only the factory owner can call this function.
    /// @param paramName name of the parameter to set (lnFeeRateRoot, protocolFeePercent)
    /// @param value value of the parameter
    function setFeeParameter(bytes32 paramName, uint256 value) external {
        if (factory.owner() != msg.sender) revert Errors.PoolOnlyOwner();

        if (paramName == "lnFeeRateRoot") {
            if (value > MAX_LN_FEE_RATE_ROOT) revert Errors.LnFeeRateRootTooHigh();
            lnFeeRateRoot = uint80(value); // unsafe cast here is Okay because we checked the value is less than MAX_LN_FEE_RATE_ROOT
        } else if (paramName == "protocolFeePercent") {
            if (value > MAX_PROTOCOL_FEE_PERCENT) revert Errors.ProtocolFeePercentTooHigh();
            protocolFeePercent = uint8(value); // unsafe cast here is Okay
        } else {
            revert Errors.PoolInvalidParamName();
        }
    }

    ////////////////////////////////////////////////////////////////////////////////
    // View functions
    ////////////////////////////////////////////////////////////////////////////////

    /// @notice get Principal Tokens within the pool
    function principalTokens() public view returns (IERC20[3] memory) {
        return [pt1, pt2, pt3];
    }

    /// @notice read the state of the pool
    function readState() external view returns (PoolState memory) {
        return _loadState();
    }
    /// @notice get underlying and tricrypto addresses of the pool

    function getAssets() public view returns (address, address) {
        return (address(underlying), address(tricrypto));
    }

    ////////////////////////////////////////////////////////////////////////////////
    // Util
    ////////////////////////////////////////////////////////////////////////////////

    /// @notice read the state of the pool from storage into memory
    function _loadState() internal view returns (PoolState memory state) {
        uint256 virtualPrice = tricrypto.get_virtual_price();
        state = PoolState({
            totalBaseLptTimesN: uint256(totalBaseLpt) * N_COINS * virtualPrice / WAD,
            totalUnderlying18: uint256(totalUnderlying).to18Decimals(uDecimals),
            virtualPrice: virtualPrice,
            lnFeeRateRoot: lnFeeRateRoot,
            protocolFeePercent: protocolFeePercent,
            scalarRoot: scalarRoot,
            maturity: maturity,
            lastLnImpliedRate: lastLnImpliedRate
        });
    }

    /// @notice write back the state of the pool from memory to storage
    function _writeState(PoolState memory state) internal {
        lastLnImpliedRate = state.lastLnImpliedRate;
        // Note: Actual balance of BaseLpt may be greater than `totalBaseLpt` because of rounding error.
        totalBaseLpt = (state.totalBaseLptTimesN * WAD / (N_COINS * state.virtualPrice)).toUint128();
        totalUnderlying = state.totalUnderlying18.from18Decimals(uDecimals).toUint128();

        emit UpdateLnImpliedRate(state.lastLnImpliedRate);
    }

    /// @notice credit: UniswapV3Pool
    /// @dev This function is gas optimized to avoid a redundant extcodesize check in addition to the returndatasize
    /// check
    function _balance(IERC20 token) internal view returns (uint256) {
        (bool success, bytes memory data) =
            address(token).staticcall(abi.encodeWithSelector(IERC20.balanceOf.selector, address(this)));
        require(success && data.length >= 32);
        return abi.decode(data, (uint256));
    }
}