organized_contracts/0c/0c0f27c6396f251804500a03f1aa080821984622ed58be9edb8b6384d60dfe2b/main.sol

// This contract is part of Zellic’s smart contract dataset, which is a collection of publicly available contract code gathered as of March 2023.

// SPDX-License-Identifier: MIT
// File: @openzeppelin/contracts/utils/math/Math.sol


// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/Math.sol)

pragma solidity ^0.8.0;

/**

 * @dev Standard math utilities missing in the Solidity language.

 */
library Math {
    enum Rounding {
        Down, // Toward negative infinity
        Up, // Toward infinity
        Zero // Toward zero
    }

    /**

     * @dev Returns the largest of two numbers.

     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }

    /**

     * @dev Returns the smallest of two numbers.

     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /**

     * @dev Returns the average of two numbers. The result is rounded towards

     * zero.

     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow.
        return (a & b) + (a ^ b) / 2;
    }

    /**

     * @dev Returns the ceiling of the division of two numbers.

     *

     * This differs from standard division with `/` in that it rounds up instead

     * of rounding down.

     */
    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b - 1) / b can overflow on addition, so we distribute.
        return a == 0 ? 0 : (a - 1) / b + 1;
    }

    /**

     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0

     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)

     * with further edits by Uniswap Labs also under MIT license.

     */
    function mulDiv(

        uint256 x,

        uint256 y,

        uint256 denominator

    ) internal pure returns (uint256 result) {
        unchecked {
            // 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 {
                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) {
                return prod0 / denominator;
            }

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

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

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

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

            // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
            // See https://cs.stackexchange.com/q/138556/92363.

            // Does not overflow because the denominator cannot be zero at this stage in the function.
            uint256 twos = denominator & (~denominator + 1);
            assembly {
                // Divide denominator by twos.
                denominator := div(denominator, twos)

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

                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                twos := add(div(sub(0, twos), twos), 1)
            }

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

            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct 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;
            return result;
        }
    }

    /**

     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.

     */
    function mulDiv(

        uint256 x,

        uint256 y,

        uint256 denominator,

        Rounding rounding

    ) internal pure returns (uint256) {
        uint256 result = mulDiv(x, y, denominator);
        if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
            result += 1;
        }
        return result;
    }

    /**

     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.

     *

     * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).

     */
    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        //
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
        //
        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
        //
        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1 << (log2(a) >> 1);

        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
        // 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 + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            return min(result, a / result);
        }
    }

    /**

     * @notice Calculates sqrt(a), following the selected rounding direction.

     */
    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
        }
    }

    /**

     * @dev Return the log in base 2, rounded down, of a positive value.

     * Returns 0 if given 0.

     */
    function log2(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 128;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 64;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 32;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 16;
            }
            if (value >> 8 > 0) {
                value >>= 8;
                result += 8;
            }
            if (value >> 4 > 0) {
                value >>= 4;
                result += 4;
            }
            if (value >> 2 > 0) {
                value >>= 2;
                result += 2;
            }
            if (value >> 1 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**

     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.

     * Returns 0 if given 0.

     */
    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
        }
    }

    /**

     * @dev Return the log in base 10, rounded down, of a positive value.

     * Returns 0 if given 0.

     */
    function log10(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >= 10**64) {
                value /= 10**64;
                result += 64;
            }
            if (value >= 10**32) {
                value /= 10**32;
                result += 32;
            }
            if (value >= 10**16) {
                value /= 10**16;
                result += 16;
            }
            if (value >= 10**8) {
                value /= 10**8;
                result += 8;
            }
            if (value >= 10**4) {
                value /= 10**4;
                result += 4;
            }
            if (value >= 10**2) {
                value /= 10**2;
                result += 2;
            }
            if (value >= 10**1) {
                result += 1;
            }
        }
        return result;
    }

    /**

     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.

     * Returns 0 if given 0.

     */
    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (rounding == Rounding.Up && 10**result < value ? 1 : 0);
        }
    }

    /**

     * @dev Return the log in base 256, rounded down, of a positive value.

     * Returns 0 if given 0.

     *

     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.

     */
    function log256(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 16;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 8;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 4;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 2;
            }
            if (value >> 8 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**

     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.

     * Returns 0 if given 0.

     */
    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log256(value);
            return result + (rounding == Rounding.Up && 1 << (result * 8) < value ? 1 : 0);
        }
    }
}

// File: @openzeppelin/contracts/utils/Strings.sol


// OpenZeppelin Contracts (last updated v4.8.0) (utils/Strings.sol)

pragma solidity ^0.8.0;


/**

 * @dev String operations.

 */
library Strings {
    bytes16 private constant _SYMBOLS = "0123456789abcdef";
    uint8 private constant _ADDRESS_LENGTH = 20;

    /**

     * @dev Converts a `uint256` to its ASCII `string` decimal representation.

     */
    function toString(uint256 value) internal pure returns (string memory) {
        unchecked {
            uint256 length = Math.log10(value) + 1;
            string memory buffer = new string(length);
            uint256 ptr;
            /// @solidity memory-safe-assembly
            assembly {
                ptr := add(buffer, add(32, length))
            }
            while (true) {
                ptr--;
                /// @solidity memory-safe-assembly
                assembly {
                    mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                }
                value /= 10;
                if (value == 0) break;
            }
            return buffer;
        }
    }

    /**

     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.

     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        unchecked {
            return toHexString(value, Math.log256(value) + 1);
        }
    }

    /**

     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.

     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        bytes memory buffer = new bytes(2 * length + 2);
        buffer[0] = "0";
        buffer[1] = "x";
        for (uint256 i = 2 * length + 1; i > 1; --i) {
            buffer[i] = _SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }

    /**

     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.

     */
    function toHexString(address addr) internal pure returns (string memory) {
        return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
    }
}

// File: @openzeppelin/contracts/utils/Context.sol


// 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;
    }
}

// File: @openzeppelin/contracts/security/Pausable.sol


// OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)

pragma solidity ^0.8.0;


/**

 * @dev Contract module which allows children to implement an emergency stop

 * mechanism that can be triggered by an authorized account.

 *

 * This module is used through inheritance. It will make available the

 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to

 * the functions of your contract. Note that they will not be pausable by

 * simply including this module, only once the modifiers are put in place.

 */
abstract contract Pausable is Context {
    /**

     * @dev Emitted when the pause is triggered by `account`.

     */
    event Paused(address account);

    /**

     * @dev Emitted when the pause is lifted by `account`.

     */
    event Unpaused(address account);

    bool private _paused;

    /**

     * @dev Initializes the contract in unpaused state.

     */
    constructor() {
        _paused = false;
    }

    /**

     * @dev Modifier to make a function callable only when the contract is not paused.

     *

     * Requirements:

     *

     * - The contract must not be paused.

     */
    modifier whenNotPaused() {
        _requireNotPaused();
        _;
    }

    /**

     * @dev Modifier to make a function callable only when the contract is paused.

     *

     * Requirements:

     *

     * - The contract must be paused.

     */
    modifier whenPaused() {
        _requirePaused();
        _;
    }

    /**

     * @dev Returns true if the contract is paused, and false otherwise.

     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**

     * @dev Throws if the contract is paused.

     */
    function _requireNotPaused() internal view virtual {
        require(!paused(), "Pausable: paused");
    }

    /**

     * @dev Throws if the contract is not paused.

     */
    function _requirePaused() internal view virtual {
        require(paused(), "Pausable: not paused");
    }

    /**

     * @dev Triggers stopped state.

     *

     * Requirements:

     *

     * - The contract must not be paused.

     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**

     * @dev Returns to normal state.

     *

     * Requirements:

     *

     * - The contract must be paused.

     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}

// File: @openzeppelin/contracts/access/Ownable.sol


// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;


/**

 * @dev Contract module which provides a basic access control mechanism, where

 * there is an account (an owner) that can be granted exclusive access to

 * specific functions.

 *

 * By default, the owner account will be the one that deploys the contract. This

 * can later be changed with {transferOwnership}.

 *

 * This module is used through inheritance. It will make available the modifier

 * `onlyOwner`, which can be applied to your functions to restrict their use to

 * the owner.

 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**

     * @dev Initializes the contract setting the deployer as the initial owner.

     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**

     * @dev Throws if called by any account other than the owner.

     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**

     * @dev Returns the address of the current owner.

     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**

     * @dev Throws if the sender is not the owner.

     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**

     * @dev Leaves the contract without owner. It will not be possible to call

     * `onlyOwner` functions anymore. Can only be called by the current owner.

     *

     * NOTE: Renouncing ownership will leave the contract without an owner,

     * thereby removing any functionality that is only available to the owner.

     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**

     * @dev Transfers ownership of the contract to a new account (`newOwner`).

     * Can only be called by the current owner.

     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**

     * @dev Transfers ownership of the contract to a new account (`newOwner`).

     * Internal function without access restriction.

     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// File: @openzeppelin/contracts/utils/Address.sol


// OpenZeppelin Contracts (last updated v4.8.0) (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

     * ====

     *

     * [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://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].

     *

     * IMPORTANT: because control is transferred to `recipient`, care must be

     * taken to not create reentrancy vulnerabilities. Consider using

     * {ReentrancyGuard} or the

     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].

     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (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);
        }
    }
}

// File: @openzeppelin/contracts/utils/introspection/IERC165.sol


// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)

pragma solidity ^0.8.0;

/**

 * @dev Interface of the ERC165 standard, as defined in the

 * https://eips.ethereum.org/EIPS/eip-165[EIP].

 *

 * Implementers can declare support of contract interfaces, which can then be

 * queried by others ({ERC165Checker}).

 *

 * For an implementation, see {ERC165}.

 */
interface IERC165 {
    /**

     * @dev Returns true if this contract implements the interface defined by

     * `interfaceId`. See the corresponding

     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]

     * to learn more about how these ids are created.

     *

     * This function call must use less than 30 000 gas.

     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

// File: @openzeppelin/contracts/interfaces/IERC2981.sol


// OpenZeppelin Contracts (last updated v4.6.0) (interfaces/IERC2981.sol)

pragma solidity ^0.8.0;


/**

 * @dev Interface for the NFT Royalty Standard.

 *

 * A standardized way to retrieve royalty payment information for non-fungible tokens (NFTs) to enable universal

 * support for royalty payments across all NFT marketplaces and ecosystem participants.

 *

 * _Available since v4.5._

 */
interface IERC2981 is IERC165 {
    /**

     * @dev Returns how much royalty is owed and to whom, based on a sale price that may be denominated in any unit of

     * exchange. The royalty amount is denominated and should be paid in that same unit of exchange.

     */
    function royaltyInfo(uint256 tokenId, uint256 salePrice)

        external

        view

        returns (address receiver, uint256 royaltyAmount);
}

// File: @openzeppelin/contracts/utils/introspection/ERC165.sol


// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)

pragma solidity ^0.8.0;


/**

 * @dev Implementation of the {IERC165} interface.

 *

 * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check

 * for the additional interface id that will be supported. For example:

 *

 * ```solidity

 * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {

 *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);

 * }

 * ```

 *

 * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.

 */
abstract contract ERC165 is IERC165 {
    /**

     * @dev See {IERC165-supportsInterface}.

     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IERC165).interfaceId;
    }
}

// File: @openzeppelin/contracts/token/ERC1155/IERC1155Receiver.sol


// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC1155/IERC1155Receiver.sol)

pragma solidity ^0.8.0;


/**

 * @dev _Available since v3.1._

 */
interface IERC1155Receiver is IERC165 {
    /**

     * @dev Handles the receipt of a single ERC1155 token type. This function is

     * called at the end of a `safeTransferFrom` after the balance has been updated.

     *

     * NOTE: To accept the transfer, this must return

     * `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`

     * (i.e. 0xf23a6e61, or its own function selector).

     *

     * @param operator The address which initiated the transfer (i.e. msg.sender)

     * @param from The address which previously owned the token

     * @param id The ID of the token being transferred

     * @param value The amount of tokens being transferred

     * @param data Additional data with no specified format

     * @return `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))` if transfer is allowed

     */
    function onERC1155Received(

        address operator,

        address from,

        uint256 id,

        uint256 value,

        bytes calldata data

    ) external returns (bytes4);

    /**

     * @dev Handles the receipt of a multiple ERC1155 token types. This function

     * is called at the end of a `safeBatchTransferFrom` after the balances have

     * been updated.

     *

     * NOTE: To accept the transfer(s), this must return

     * `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`

     * (i.e. 0xbc197c81, or its own function selector).

     *

     * @param operator The address which initiated the batch transfer (i.e. msg.sender)

     * @param from The address which previously owned the token

     * @param ids An array containing ids of each token being transferred (order and length must match values array)

     * @param values An array containing amounts of each token being transferred (order and length must match ids array)

     * @param data Additional data with no specified format

     * @return `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))` if transfer is allowed

     */
    function onERC1155BatchReceived(

        address operator,

        address from,

        uint256[] calldata ids,

        uint256[] calldata values,

        bytes calldata data

    ) external returns (bytes4);
}

// File: @openzeppelin/contracts/token/ERC1155/IERC1155.sol


// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC1155/IERC1155.sol)

pragma solidity ^0.8.0;


/**

 * @dev Required interface of an ERC1155 compliant contract, as defined in the

 * https://eips.ethereum.org/EIPS/eip-1155[EIP].

 *

 * _Available since v3.1._

 */
interface IERC1155 is IERC165 {
    /**

     * @dev Emitted when `value` tokens of token type `id` are transferred from `from` to `to` by `operator`.

     */
    event TransferSingle(address indexed operator, address indexed from, address indexed to, uint256 id, uint256 value);

    /**

     * @dev Equivalent to multiple {TransferSingle} events, where `operator`, `from` and `to` are the same for all

     * transfers.

     */
    event TransferBatch(
        address indexed operator,
        address indexed from,
        address indexed to,
        uint256[] ids,
        uint256[] values
    );

    /**

     * @dev Emitted when `account` grants or revokes permission to `operator` to transfer their tokens, according to

     * `approved`.

     */
    event ApprovalForAll(address indexed account, address indexed operator, bool approved);

    /**

     * @dev Emitted when the URI for token type `id` changes to `value`, if it is a non-programmatic URI.

     *

     * If an {URI} event was emitted for `id`, the standard

     * https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[guarantees] that `value` will equal the value

     * returned by {IERC1155MetadataURI-uri}.

     */
    event URI(string value, uint256 indexed id);

    /**

     * @dev Returns the amount of tokens of token type `id` owned by `account`.

     *

     * Requirements:

     *

     * - `account` cannot be the zero address.

     */
    function balanceOf(address account, uint256 id) external view returns (uint256);

    /**

     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {balanceOf}.

     *

     * Requirements:

     *

     * - `accounts` and `ids` must have the same length.

     */
    function balanceOfBatch(address[] calldata accounts, uint256[] calldata ids)

        external

        view

        returns (uint256[] memory);

    /**

     * @dev Grants or revokes permission to `operator` to transfer the caller's tokens, according to `approved`,

     *

     * Emits an {ApprovalForAll} event.

     *

     * Requirements:

     *

     * - `operator` cannot be the caller.

     */
    function setApprovalForAll(address operator, bool approved) external;

    /**

     * @dev Returns true if `operator` is approved to transfer ``account``'s tokens.

     *

     * See {setApprovalForAll}.

     */
    function isApprovedForAll(address account, address operator) external view returns (bool);

    /**

     * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.

     *

     * Emits a {TransferSingle} event.

     *

     * Requirements:

     *

     * - `to` cannot be the zero address.

     * - If the caller is not `from`, it must have been approved to spend ``from``'s tokens via {setApprovalForAll}.

     * - `from` must have a balance of tokens of type `id` of at least `amount`.

     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the

     * acceptance magic value.

     */
    function safeTransferFrom(

        address from,

        address to,

        uint256 id,

        uint256 amount,

        bytes calldata data

    ) external;

    /**

     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {safeTransferFrom}.

     *

     * Emits a {TransferBatch} event.

     *

     * Requirements:

     *

     * - `ids` and `amounts` must have the same length.

     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the

     * acceptance magic value.

     */
    function safeBatchTransferFrom(

        address from,

        address to,

        uint256[] calldata ids,

        uint256[] calldata amounts,

        bytes calldata data

    ) external;
}

// File: @openzeppelin/contracts/token/ERC1155/extensions/IERC1155MetadataURI.sol


// OpenZeppelin Contracts v4.4.1 (token/ERC1155/extensions/IERC1155MetadataURI.sol)

pragma solidity ^0.8.0;


/**

 * @dev Interface of the optional ERC1155MetadataExtension interface, as defined

 * in the https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[EIP].

 *

 * _Available since v3.1._

 */
interface IERC1155MetadataURI is IERC1155 {
    /**

     * @dev Returns the URI for token type `id`.

     *

     * If the `\{id\}` substring is present in the URI, it must be replaced by

     * clients with the actual token type ID.

     */
    function uri(uint256 id) external view returns (string memory);
}

// File: @openzeppelin/contracts/token/ERC1155/ERC1155.sol


// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC1155/ERC1155.sol)

pragma solidity ^0.8.0;







/**

 * @dev Implementation of the basic standard multi-token.

 * See https://eips.ethereum.org/EIPS/eip-1155

 * Originally based on code by Enjin: https://github.com/enjin/erc-1155

 *

 * _Available since v3.1._

 */
contract ERC1155 is Context, ERC165, IERC1155, IERC1155MetadataURI {
    using Address for address;

    // Mapping from token ID to account balances
    mapping(uint256 => mapping(address => uint256)) private _balances;

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

    // Used as the URI for all token types by relying on ID substitution, e.g. https://token-cdn-domain/{id}.json
    string private _uri;

    /**

     * @dev See {_setURI}.

     */
    constructor(string memory uri_) {
        _setURI(uri_);
    }

    /**

     * @dev See {IERC165-supportsInterface}.

     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
        return
            interfaceId == type(IERC1155).interfaceId ||
            interfaceId == type(IERC1155MetadataURI).interfaceId ||
            super.supportsInterface(interfaceId);
    }

    /**

     * @dev See {IERC1155MetadataURI-uri}.

     *

     * This implementation returns the same URI for *all* token types. It relies

     * on the token type ID substitution mechanism

     * https://eips.ethereum.org/EIPS/eip-1155#metadata[defined in the EIP].

     *

     * Clients calling this function must replace the `\{id\}` substring with the

     * actual token type ID.

     */
    function uri(uint256) public view virtual override returns (string memory) {
        return _uri;
    }

    /**

     * @dev See {IERC1155-balanceOf}.

     *

     * Requirements:

     *

     * - `account` cannot be the zero address.

     */
    function balanceOf(address account, uint256 id) public view virtual override returns (uint256) {
        require(account != address(0), "ERC1155: address zero is not a valid owner");
        return _balances[id][account];
    }

    /**

     * @dev See {IERC1155-balanceOfBatch}.

     *

     * Requirements:

     *

     * - `accounts` and `ids` must have the same length.

     */
    function balanceOfBatch(address[] memory accounts, uint256[] memory ids)

        public

        view

        virtual

        override

        returns (uint256[] memory)

    {
        require(accounts.length == ids.length, "ERC1155: accounts and ids length mismatch");

        uint256[] memory batchBalances = new uint256[](accounts.length);

        for (uint256 i = 0; i < accounts.length; ++i) {
            batchBalances[i] = balanceOf(accounts[i], ids[i]);
        }

        return batchBalances;
    }

    /**

     * @dev See {IERC1155-setApprovalForAll}.

     */
    function setApprovalForAll(address operator, bool approved) public virtual override {
        _setApprovalForAll(_msgSender(), operator, approved);
    }

    /**

     * @dev See {IERC1155-isApprovedForAll}.

     */
    function isApprovedForAll(address account, address operator) public view virtual override returns (bool) {
        return _operatorApprovals[account][operator];
    }

    /**

     * @dev See {IERC1155-safeTransferFrom}.

     */
    function safeTransferFrom(

        address from,

        address to,

        uint256 id,

        uint256 amount,

        bytes memory data

    ) public virtual override {
        require(
            from == _msgSender() || isApprovedForAll(from, _msgSender()),
            "ERC1155: caller is not token owner or approved"
        );
        _safeTransferFrom(from, to, id, amount, data);
    }

    /**

     * @dev See {IERC1155-safeBatchTransferFrom}.

     */
    function safeBatchTransferFrom(

        address from,

        address to,

        uint256[] memory ids,

        uint256[] memory amounts,

        bytes memory data

    ) public virtual override {
        require(
            from == _msgSender() || isApprovedForAll(from, _msgSender()),
            "ERC1155: caller is not token owner or approved"
        );
        _safeBatchTransferFrom(from, to, ids, amounts, data);
    }

    /**

     * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.

     *

     * Emits a {TransferSingle} event.

     *

     * Requirements:

     *

     * - `to` cannot be the zero address.

     * - `from` must have a balance of tokens of type `id` of at least `amount`.

     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the

     * acceptance magic value.

     */
    function _safeTransferFrom(

        address from,

        address to,

        uint256 id,

        uint256 amount,

        bytes memory data

    ) internal virtual {
        require(to != address(0), "ERC1155: transfer to the zero address");

        address operator = _msgSender();
        uint256[] memory ids = _asSingletonArray(id);
        uint256[] memory amounts = _asSingletonArray(amount);

        _beforeTokenTransfer(operator, from, to, ids, amounts, data);

        uint256 fromBalance = _balances[id][from];
        require(fromBalance >= amount, "ERC1155: insufficient balance for transfer");
        unchecked {
            _balances[id][from] = fromBalance - amount;
        }
        _balances[id][to] += amount;

        emit TransferSingle(operator, from, to, id, amount);

        _afterTokenTransfer(operator, from, to, ids, amounts, data);

        _doSafeTransferAcceptanceCheck(operator, from, to, id, amount, data);
    }

    /**

     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_safeTransferFrom}.

     *

     * Emits a {TransferBatch} event.

     *

     * Requirements:

     *

     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the

     * acceptance magic value.

     */
    function _safeBatchTransferFrom(

        address from,

        address to,

        uint256[] memory ids,

        uint256[] memory amounts,

        bytes memory data

    ) internal virtual {
        require(ids.length == amounts.length, "ERC1155: ids and amounts length mismatch");
        require(to != address(0), "ERC1155: transfer to the zero address");

        address operator = _msgSender();

        _beforeTokenTransfer(operator, from, to, ids, amounts, data);

        for (uint256 i = 0; i < ids.length; ++i) {
            uint256 id = ids[i];
            uint256 amount = amounts[i];

            uint256 fromBalance = _balances[id][from];
            require(fromBalance >= amount, "ERC1155: insufficient balance for transfer");
            unchecked {
                _balances[id][from] = fromBalance - amount;
            }
            _balances[id][to] += amount;
        }

        emit TransferBatch(operator, from, to, ids, amounts);

        _afterTokenTransfer(operator, from, to, ids, amounts, data);

        _doSafeBatchTransferAcceptanceCheck(operator, from, to, ids, amounts, data);
    }

    /**

     * @dev Sets a new URI for all token types, by relying on the token type ID

     * substitution mechanism

     * https://eips.ethereum.org/EIPS/eip-1155#metadata[defined in the EIP].

     *

     * By this mechanism, any occurrence of the `\{id\}` substring in either the

     * URI or any of the amounts in the JSON file at said URI will be replaced by

     * clients with the token type ID.

     *

     * For example, the `https://token-cdn-domain/\{id\}.json` URI would be

     * interpreted by clients as

     * `https://token-cdn-domain/000000000000000000000000000000000000000000000000000000000004cce0.json`

     * for token type ID 0x4cce0.

     *

     * See {uri}.

     *

     * Because these URIs cannot be meaningfully represented by the {URI} event,

     * this function emits no events.

     */
    function _setURI(string memory newuri) internal virtual {
        _uri = newuri;
    }

    /**

     * @dev Creates `amount` tokens of token type `id`, and assigns them to `to`.

     *

     * Emits a {TransferSingle} event.

     *

     * Requirements:

     *

     * - `to` cannot be the zero address.

     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the

     * acceptance magic value.

     */
    function _mint(

        address to,

        uint256 id,

        uint256 amount,

        bytes memory data

    ) internal virtual {
        require(to != address(0), "ERC1155: mint to the zero address");

        address operator = _msgSender();
        uint256[] memory ids = _asSingletonArray(id);
        uint256[] memory amounts = _asSingletonArray(amount);

        _beforeTokenTransfer(operator, address(0), to, ids, amounts, data);

        _balances[id][to] += amount;
        emit TransferSingle(operator, address(0), to, id, amount);

        _afterTokenTransfer(operator, address(0), to, ids, amounts, data);

        _doSafeTransferAcceptanceCheck(operator, address(0), to, id, amount, data);
    }

    /**

     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_mint}.

     *

     * Emits a {TransferBatch} event.

     *

     * Requirements:

     *

     * - `ids` and `amounts` must have the same length.

     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the

     * acceptance magic value.

     */
    function _mintBatch(

        address to,

        uint256[] memory ids,

        uint256[] memory amounts,

        bytes memory data

    ) internal virtual {
        require(to != address(0), "ERC1155: mint to the zero address");
        require(ids.length == amounts.length, "ERC1155: ids and amounts length mismatch");

        address operator = _msgSender();

        _beforeTokenTransfer(operator, address(0), to, ids, amounts, data);

        for (uint256 i = 0; i < ids.length; i++) {
            _balances[ids[i]][to] += amounts[i];
        }

        emit TransferBatch(operator, address(0), to, ids, amounts);

        _afterTokenTransfer(operator, address(0), to, ids, amounts, data);

        _doSafeBatchTransferAcceptanceCheck(operator, address(0), to, ids, amounts, data);
    }

    /**

     * @dev Destroys `amount` tokens of token type `id` from `from`

     *

     * Emits a {TransferSingle} event.

     *

     * Requirements:

     *

     * - `from` cannot be the zero address.

     * - `from` must have at least `amount` tokens of token type `id`.

     */
    function _burn(

        address from,

        uint256 id,

        uint256 amount

    ) internal virtual {
        require(from != address(0), "ERC1155: burn from the zero address");

        address operator = _msgSender();
        uint256[] memory ids = _asSingletonArray(id);
        uint256[] memory amounts = _asSingletonArray(amount);

        _beforeTokenTransfer(operator, from, address(0), ids, amounts, "");

        uint256 fromBalance = _balances[id][from];
        require(fromBalance >= amount, "ERC1155: burn amount exceeds balance");
        unchecked {
            _balances[id][from] = fromBalance - amount;
        }

        emit TransferSingle(operator, from, address(0), id, amount);

        _afterTokenTransfer(operator, from, address(0), ids, amounts, "");
    }

    /**

     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_burn}.

     *

     * Emits a {TransferBatch} event.

     *

     * Requirements:

     *

     * - `ids` and `amounts` must have the same length.

     */
    function _burnBatch(

        address from,

        uint256[] memory ids,

        uint256[] memory amounts

    ) internal virtual {
        require(from != address(0), "ERC1155: burn from the zero address");
        require(ids.length == amounts.length, "ERC1155: ids and amounts length mismatch");

        address operator = _msgSender();

        _beforeTokenTransfer(operator, from, address(0), ids, amounts, "");

        for (uint256 i = 0; i < ids.length; i++) {
            uint256 id = ids[i];
            uint256 amount = amounts[i];

            uint256 fromBalance = _balances[id][from];
            require(fromBalance >= amount, "ERC1155: burn amount exceeds balance");
            unchecked {
                _balances[id][from] = fromBalance - amount;
            }
        }

        emit TransferBatch(operator, from, address(0), ids, amounts);

        _afterTokenTransfer(operator, from, address(0), ids, amounts, "");
    }

    /**

     * @dev Approve `operator` to operate on all of `owner` tokens

     *

     * Emits an {ApprovalForAll} event.

     */
    function _setApprovalForAll(

        address owner,

        address operator,

        bool approved

    ) internal virtual {
        require(owner != operator, "ERC1155: setting approval status for self");
        _operatorApprovals[owner][operator] = approved;
        emit ApprovalForAll(owner, operator, approved);
    }

    /**

     * @dev Hook that is called before any token transfer. This includes minting

     * and burning, as well as batched variants.

     *

     * The same hook is called on both single and batched variants. For single

     * transfers, the length of the `ids` and `amounts` arrays will be 1.

     *

     * Calling conditions (for each `id` and `amount` pair):

     *

     * - When `from` and `to` are both non-zero, `amount` of ``from``'s tokens

     * of token type `id` will be  transferred to `to`.

     * - When `from` is zero, `amount` tokens of token type `id` will be minted

     * for `to`.

     * - when `to` is zero, `amount` of ``from``'s tokens of token type `id`

     * will be burned.

     * - `from` and `to` are never both zero.

     * - `ids` and `amounts` have the same, non-zero length.

     *

     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].

     */
    function _beforeTokenTransfer(

        address operator,

        address from,

        address to,

        uint256[] memory ids,

        uint256[] memory amounts,

        bytes memory data

    ) internal virtual {}

    /**

     * @dev Hook that is called after any token transfer. This includes minting

     * and burning, as well as batched variants.

     *

     * The same hook is called on both single and batched variants. For single

     * transfers, the length of the `id` and `amount` arrays will be 1.

     *

     * Calling conditions (for each `id` and `amount` pair):

     *

     * - When `from` and `to` are both non-zero, `amount` of ``from``'s tokens

     * of token type `id` will be  transferred to `to`.

     * - When `from` is zero, `amount` tokens of token type `id` will be minted

     * for `to`.

     * - when `to` is zero, `amount` of ``from``'s tokens of token type `id`

     * will be burned.

     * - `from` and `to` are never both zero.

     * - `ids` and `amounts` have the same, non-zero length.

     *

     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].

     */
    function _afterTokenTransfer(

        address operator,

        address from,

        address to,

        uint256[] memory ids,

        uint256[] memory amounts,

        bytes memory data

    ) internal virtual {}

    function _doSafeTransferAcceptanceCheck(

        address operator,

        address from,

        address to,

        uint256 id,

        uint256 amount,

        bytes memory data

    ) private {
        if (to.isContract()) {
            try IERC1155Receiver(to).onERC1155Received(operator, from, id, amount, data) returns (bytes4 response) {
                if (response != IERC1155Receiver.onERC1155Received.selector) {
                    revert("ERC1155: ERC1155Receiver rejected tokens");
                }
            } catch Error(string memory reason) {
                revert(reason);
            } catch {
                revert("ERC1155: transfer to non-ERC1155Receiver implementer");
            }
        }
    }

    function _doSafeBatchTransferAcceptanceCheck(

        address operator,

        address from,

        address to,

        uint256[] memory ids,

        uint256[] memory amounts,

        bytes memory data

    ) private {
        if (to.isContract()) {
            try IERC1155Receiver(to).onERC1155BatchReceived(operator, from, ids, amounts, data) returns (
                bytes4 response
            ) {
                if (response != IERC1155Receiver.onERC1155BatchReceived.selector) {
                    revert("ERC1155: ERC1155Receiver rejected tokens");
                }
            } catch Error(string memory reason) {
                revert(reason);
            } catch {
                revert("ERC1155: transfer to non-ERC1155Receiver implementer");
            }
        }
    }

    function _asSingletonArray(uint256 element) private pure returns (uint256[] memory) {
        uint256[] memory array = new uint256[](1);
        array[0] = element;

        return array;
    }
}

// File: @openzeppelin/contracts/token/ERC1155/extensions/ERC1155URIStorage.sol


// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC1155/extensions/ERC1155URIStorage.sol)

pragma solidity ^0.8.0;



/**

 * @dev ERC1155 token with storage based token URI management.

 * Inspired by the ERC721URIStorage extension

 *

 * _Available since v4.6._

 */
abstract contract ERC1155URIStorage is ERC1155 {
    using Strings for uint256;

    // Optional base URI
    string private _baseURI = "";

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

    /**

     * @dev See {IERC1155MetadataURI-uri}.

     *

     * This implementation returns the concatenation of the `_baseURI`

     * and the token-specific uri if the latter is set

     *

     * This enables the following behaviors:

     *

     * - if `_tokenURIs[tokenId]` is set, then the result is the concatenation

     *   of `_baseURI` and `_tokenURIs[tokenId]` (keep in mind that `_baseURI`

     *   is empty per default);

     *

     * - if `_tokenURIs[tokenId]` is NOT set then we fallback to `super.uri()`

     *   which in most cases will contain `ERC1155._uri`;

     *

     * - if `_tokenURIs[tokenId]` is NOT set, and if the parents do not have a

     *   uri value set, then the result is empty.

     */
    function uri(uint256 tokenId) public view virtual override returns (string memory) {
        string memory tokenURI = _tokenURIs[tokenId];

        // If token URI is set, concatenate base URI and tokenURI (via abi.encodePacked).
        return bytes(tokenURI).length > 0 ? string(abi.encodePacked(_baseURI, tokenURI)) : super.uri(tokenId);
    }

    /**

     * @dev Sets `tokenURI` as the tokenURI of `tokenId`.

     */
    function _setURI(uint256 tokenId, string memory tokenURI) internal virtual {
        _tokenURIs[tokenId] = tokenURI;
        emit URI(uri(tokenId), tokenId);
    }

    /**

     * @dev Sets `baseURI` as the `_baseURI` for all tokens

     */
    function _setBaseURI(string memory baseURI) internal virtual {
        _baseURI = baseURI;
    }
}

// File: @openzeppelin/contracts/token/ERC1155/extensions/ERC1155Supply.sol


// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC1155/extensions/ERC1155Supply.sol)

pragma solidity ^0.8.0;


/**

 * @dev Extension of ERC1155 that adds tracking of total supply per id.

 *

 * Useful for scenarios where Fungible and Non-fungible tokens have to be

 * clearly identified. Note: While a totalSupply of 1 might mean the

 * corresponding is an NFT, there is no guarantees that no other token with the

 * same id are not going to be minted.

 */
abstract contract ERC1155Supply is ERC1155 {
    mapping(uint256 => uint256) private _totalSupply;

    /**

     * @dev Total amount of tokens in with a given id.

     */
    function totalSupply(uint256 id) public view virtual returns (uint256) {
        return _totalSupply[id];
    }

    /**

     * @dev Indicates whether any token exist with a given id, or not.

     */
    function exists(uint256 id) public view virtual returns (bool) {
        return ERC1155Supply.totalSupply(id) > 0;
    }

    /**

     * @dev See {ERC1155-_beforeTokenTransfer}.

     */
    function _beforeTokenTransfer(

        address operator,

        address from,

        address to,

        uint256[] memory ids,

        uint256[] memory amounts,

        bytes memory data

    ) internal virtual override {
        super._beforeTokenTransfer(operator, from, to, ids, amounts, data);

        if (from == address(0)) {
            for (uint256 i = 0; i < ids.length; ++i) {
                _totalSupply[ids[i]] += amounts[i];
            }
        }

        if (to == address(0)) {
            for (uint256 i = 0; i < ids.length; ++i) {
                uint256 id = ids[i];
                uint256 amount = amounts[i];
                uint256 supply = _totalSupply[id];
                require(supply >= amount, "ERC1155: burn amount exceeds totalSupply");
                unchecked {
                    _totalSupply[id] = supply - amount;
                }
            }
        }
    }
}

// File: @openzeppelin/contracts/token/ERC1155/extensions/ERC1155Burnable.sol


// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC1155/extensions/ERC1155Burnable.sol)

pragma solidity ^0.8.0;


/**

 * @dev Extension of {ERC1155} that allows token holders to destroy both their

 * own tokens and those that they have been approved to use.

 *

 * _Available since v3.1._

 */
abstract contract ERC1155Burnable is ERC1155 {
    function burn(

        address account,

        uint256 id,

        uint256 value

    ) public virtual {
        require(
            account == _msgSender() || isApprovedForAll(account, _msgSender()),
            "ERC1155: caller is not token owner or approved"
        );

        _burn(account, id, value);
    }

    function burnBatch(

        address account,

        uint256[] memory ids,

        uint256[] memory values

    ) public virtual {
        require(
            account == _msgSender() || isApprovedForAll(account, _msgSender()),
            "ERC1155: caller is not token owner or approved"
        );

        _burnBatch(account, ids, values);
    }
}

// File: ump.sol


pragma solidity ^0.8.0;








interface IOperatorFilterRegistry {
    function isOperatorAllowed(address registrant, address operator)

        external

        view

        returns (bool);

    function register(address registrant) external;

    function registerAndSubscribe(address registrant, address subscription)

        external;

    function registerAndCopyEntries(

        address registrant,

        address registrantToCopy

    ) external;

    function unregister(address addr) external;

    function updateOperator(

        address registrant,

        address operator,

        bool filtered

    ) external;

    function updateOperators(

        address registrant,

        address[] calldata operators,

        bool filtered

    ) external;

    function updateCodeHash(

        address registrant,

        bytes32 codehash,

        bool filtered

    ) external;

    function updateCodeHashes(

        address registrant,

        bytes32[] calldata codeHashes,

        bool filtered

    ) external;

    function subscribe(address registrant, address registrantToSubscribe)

        external;

    function unsubscribe(address registrant, bool copyExistingEntries) external;

    function subscriptionOf(address addr) external returns (address registrant);

    function subscribers(address registrant)

        external

        returns (address[] memory);

    function subscriberAt(address registrant, uint256 index)

        external

        returns (address);

    function copyEntriesOf(address registrant, address registrantToCopy)

        external;

    function isOperatorFiltered(address registrant, address operator)

        external

        returns (bool);

    function isCodeHashOfFiltered(address registrant, address operatorWithCode)

        external

        returns (bool);

    function isCodeHashFiltered(address registrant, bytes32 codeHash)

        external

        returns (bool);

    function filteredOperators(address addr)

        external

        returns (address[] memory);

    function filteredCodeHashes(address addr)

        external

        returns (bytes32[] memory);

    function filteredOperatorAt(address registrant, uint256 index)

        external

        returns (address);

    function filteredCodeHashAt(address registrant, uint256 index)

        external

        returns (bytes32);

    function isRegistered(address addr) external returns (bool);

    function codeHashOf(address addr) external returns (bytes32);
}

abstract contract OperatorFilterer {
    error OperatorNotAllowed(address operator);

    IOperatorFilterRegistry constant operatorFilterRegistry =
        IOperatorFilterRegistry(0x000000000000AAeB6D7670E522A718067333cd4E);

    constructor(address subscriptionOrRegistrantToCopy, bool subscribe) {
        // If an inheriting token contract is deployed to a network without the registry deployed, the modifier
        // will not revert, but the contract will need to be registered with the registry once it is deployed in
        // order for the modifier to filter addresses.
        if (address(operatorFilterRegistry).code.length > 0) {
            if (subscribe) {
                operatorFilterRegistry.registerAndSubscribe(
                    address(this),
                    subscriptionOrRegistrantToCopy
                );
            } else {
                if (subscriptionOrRegistrantToCopy != address(0)) {
                    operatorFilterRegistry.registerAndCopyEntries(
                        address(this),
                        subscriptionOrRegistrantToCopy
                    );
                } else {
                    operatorFilterRegistry.register(address(this));
                }
            }
        }
    }

    modifier onlyAllowedOperator(address from) virtual {
        // Check registry code length to facilitate testing in environments without a deployed registry.
        if (address(operatorFilterRegistry).code.length > 0) {
            // Allow spending tokens from addresses with balance
            // Note that this still allows listings and marketplaces with escrow to transfer tokens if transferred
            // from an EOA.
            if (from == msg.sender) {
                _;
                return;
            }
            if (
                !(operatorFilterRegistry.isOperatorAllowed(
                    address(this),
                    msg.sender
                ) &&
                    operatorFilterRegistry.isOperatorAllowed(
                        address(this),
                        from
                    ))
            ) {
                revert OperatorNotAllowed(msg.sender);
            }
        }
        _;
    }
}

abstract contract DefaultOperatorFilterer is OperatorFilterer {
    address constant DEFAULT_SUBSCRIPTION =
        address(0x3cc6CddA760b79bAfa08dF41ECFA224f810dCeB6);

    constructor() OperatorFilterer(DEFAULT_SUBSCRIPTION, true) {}
}

contract UMP is ERC1155, IERC2981, Ownable, Pausable, ERC1155Burnable, ERC1155Supply, ERC1155URIStorage, DefaultOperatorFilterer {
    enum METAL { GOLD, PLATINUM, SILVER, COPPER } // Metal types

    string public name; // NFT name.
    string public symbol; // NFT symbol.
    address private _recipient;
    uint256 private _royaltyPoint = 1000;

    uint256 _totalSupply = 3333; // Total supply of NFTs.
    uint256 _goldSupply = 33; // Total number of gold NFTs.
    uint256 _platinumSupply = 333; // Total number of platinum NFTs.
    uint256 _silverSupply = 999; // Total number of silver NFTs.
    uint256 _copperSupply = 1968; // total number of copper NFTs.

    mapping(address => uint256[]) private _userTokens; // Token ids per account.
    mapping(uint256 => METAL) private _metalType; // Metal type per token id.
    mapping(uint256 => bool) private _tokenSold; // Sell status per token id.

    event InitMetalType();
    event InitialMint(uint256[], uint256[]);
    event WithdrawAll(uint256);
    event Deposit(uint256);

    constructor() ERC1155("https://www.urbanminerproject.org/")
    {
        name = "Urban Miner Project";
        symbol = "UMP";
        _recipient = 0x9Bc9F795887eb3917CC52518818667B30A3DEF58;
        ERC1155._setURI("ipfs://bafkreie5wtkzdncvipkinttycmdeardlyurrgyacr6laoazhzckkhaaseu");
    }

    function safeTransferFrom(

        address from,

        address to,

        uint256 id,

        uint256 amount,

        bytes memory data

    ) public override onlyAllowedOperator(from) {
        super.safeTransferFrom(from, to, id, amount, data);
    }

    function safeBatchTransferFrom(

        address from,

        address to,

        uint256[] memory ids,

        uint256[] memory amounts,

        bytes memory data

    ) public override onlyAllowedOperator(from) {
        super.safeBatchTransferFrom(from, to, ids, amounts, data);
    }

    // @Pause function.
    function pause() public onlyOwner {
        _pause();
    }

    // @Unpause function
    function unpause() public onlyOwner {
        _unpause();
    }

    // @Total supply of this token.
    function totalCount() external view returns (uint256) {
        return _totalSupply;
    }

    // @Mint single NFT.
    function mint(address account, uint256 id, uint256 amount, bytes memory data)

        public

        onlyOwner

    {
        _mint(account, id, amount, data);
    }

    // @Mint batch NFTs.
    function mintBatch(address to, uint256[] memory ids, uint256[] memory amounts, bytes memory data)

        public

        onlyOwner

    {
        _mintBatch(to, ids, amounts, data);
    }

    // @Overrided this method to limit the token count of every account.
    function _beforeTokenTransfer(address operator, address from, address to, uint256[] memory ids, uint256[] memory amounts, bytes memory data)

        internal

        whenNotPaused

        override(ERC1155, ERC1155Supply)

    {
        super._beforeTokenTransfer(operator, from, to, ids, amounts, data);
        // All accounts except the owner can only own max 2 NFTs.
        require(to == owner() || _userTokens[to].length + amounts.length <= 2, "Account balance could not be bigger than 2");
    }

    // @Overrided this function to update metadata after purchasing.
    function _afterTokenTransfer(address operator, address from, address to, uint256[] memory ids, uint256[] memory amounts, bytes memory data)

        internal

        whenNotPaused

        override

    {
        uint256 fromUserBal = _userTokens[from].length;

        // Remove token ids from "from" user's _userToken list.
        for (uint256 i=0; i<ids.length; i++) {
            for (uint256 j=0; j<_userTokens[from].length; j++) {
                if (_userTokens[from][j] == ids[i]) {
                    _userTokens[from][j] = _userTokens[from][fromUserBal-1];
                    _userTokens[from].pop();
                }
            }
        }

        // Add token ids to "to" user's _userToken list.
        for (uint256 i=0; i<ids.length; i++) {
            _userTokens[to].push(ids[i]);

            // If the token is transferred from the owner, we update the metadata of that token because that is just "purchase".
            if (from == owner() && to != owner()) {
                if (_getMetalType(ids[i]) == METAL.GOLD) {
                    _setURI(ids[i], "ipfs://bafkreidxufd5j3j4lrup5qv5ga2ilc2o64ikeswjlotftnilcskoavcv4e");
                } else if (_getMetalType(ids[i]) == METAL.PLATINUM) {
                    _setURI(ids[i], "ipfs://bafkreie3qf7e6ugiocox2loylcwv24nl5gyqyz3ravc2q2iunmlewtbsrq");
                } else if (_getMetalType(ids[i]) == METAL.SILVER) {
                    _setURI(ids[i], "ipfs://bafkreibncuathwbnykwb72hvv25kuaz2lztj4ikq4njewz6h2tmg3qdcxy");
                } else {
                    _setURI(ids[i], "ipfs://bafkreic5hfunyqyojw3zdkplkjdvjkve72il2rh4occpxsj6nukralsv4u");
                }
            }
        }
        super._afterTokenTransfer(operator, from, to, ids, amounts, data);
    }

    // @Set contract level metadata.
    function contractURI() public pure returns (string memory) {
        return
            "ipfs://bafkreidi7eh5weuayslarn72jgdmvqkngbzuoqb5s3kn7dgr7gap2k6rga";
    }

    // @Random generator function.
    function getRandomNumber(uint256 max, uint256 adder) internal view returns (uint256) {
        uint256 randomHash = uint256(
            keccak256(abi.encodePacked(block.timestamp, uint256(7789), adder))
        );
        return randomHash % max;
    }

    // @Set metal type to all NFTs. Metal types are determined by random numbers.
    function _initMetalType(uint256 _initValue, uint256 goldSupply_, uint256 platinumSupply_, uint256 silverSupply_, uint256 copperSupply_) internal {
        uint256 goldCount = 0;
        uint256 platinumCount = 0;
        uint256 silverCount = 0;
        uint256 copperCount = 0;

        uint256 totalSupply = _totalSupply / 11;
        uint256 goldSupply = goldSupply_;
        uint256 platinumSupply = platinumSupply_;
        uint256 silverSupply = silverSupply_;
        uint256 copperSupply = copperSupply_;
        uint256 initValue = _initValue;

        bool[] memory usedIds = new bool[](totalSupply);
        uint256 tryCount = 0;

        while (true) {
            uint256 tmp = getRandomNumber(totalSupply, tryCount);
            tryCount ++;
            if (usedIds[tmp]) {
                while (usedIds[tmp]) {
                    tmp ++;
                    if (tmp == totalSupply) tmp = 0;
                }
            }

            // if (usedIds[tmp]) continue;
            usedIds[tmp] = true;
        
            if (goldCount < goldSupply) {
                _metalType[initValue + tmp] = METAL.GOLD;
                goldCount ++;
            } else if (platinumCount < platinumSupply) {
                _metalType[initValue + tmp] = METAL.PLATINUM;
                platinumCount ++;
            } else if (silverCount < silverSupply) {
                _metalType[initValue + tmp] = METAL.SILVER;
                silverCount ++;
            } else {
                _metalType[initValue + tmp] = METAL.COPPER;
                copperCount ++;
            }
            if (copperCount == copperSupply) break;
        }

        emit InitMetalType();
    }

    // @Init metal type for 0-302
    function initMetalType1() external onlyOwner {
        _initMetalType(0, 3, 31, 91, 178);
    }

    // @Init metal type for 303-605
    function initMetalType2() external onlyOwner {
        _initMetalType(0, 3, 31, 91, 178);
    }

    // @Init metal type for 606-908
    function initMetalType3() external onlyOwner {
        _initMetalType(0, 3, 31, 91, 178);
    }

    // @Init metal type for 909-1211
    function initMetalType4() external onlyOwner {
        _initMetalType(0, 3, 30, 91, 179);
    }

    // @Init metal type for 1212-1514
    function initMetalType5() external onlyOwner {
        _initMetalType(0, 3, 30, 91, 179);
    }

    // @Init metal type for 1515-1817
    function initMetalType6() external onlyOwner {
        _initMetalType(0, 3, 30, 91, 179);
    }

    // @Init metal type for 1818-2120
    function initMetalType7() external onlyOwner {
        _initMetalType(0, 3, 30, 91, 179);
    }

    // @Init metal type for 2121-2423
    function initMetalType8() external onlyOwner {
        _initMetalType(0, 3, 30, 91, 179);
    }

    // @Init metal type for 2424-2726
    function initMetalType9() external onlyOwner {
        _initMetalType(0, 3, 30, 91, 179);
    }

    // @Init metal type for 2727-3032
    function initMetalType10() external onlyOwner {
        _initMetalType(0, 3, 30, 90, 180);
    }

    // @Init metal type for 3030-3332
    function initMetalType11() external onlyOwner {
        _initMetalType(0, 3, 30, 90, 180);
    }

    // @Get metal type for given token id.
    function _getMetalType(uint256 tokenId) internal view returns (METAL) {
        return _metalType[tokenId];
    }

    // @Get metal type for given token id.
    function getMetalType(uint256 tokenId) external view onlyOwner returns (METAL) {
        return _metalType[tokenId];
    }

    // Mint batch of tokens and transfer it to the owner to list in opensea.
    function initialMint(uint256 fromId, uint256 toId) onlyOwner external {
        require(toId > fromId, "You need mint at least 1 NFT");
        uint256[] memory ids = new uint256[](toId - fromId + 1);
        uint256[] memory amounts = new uint256[](toId - fromId + 1);

        for (uint256 i=fromId; i<=toId; i++) {
            ids[i] = i;
            amounts[i] = 1;
        }

        mintBatch(owner(), ids, amounts, "0x");
        _userTokens[owner()] = ids;

        emit InitialMint(ids, amounts);
    }

    // @Get token owned by specific account.
    function getUserTokenIds(address user) external view returns (uint256[] memory) {
        return _userTokens[user];
    }

    // @Ger how many each type of metal users own.
    function getUserBalance(address user) external view returns (uint256, uint256, uint256, uint256) {
        uint256 goldCount = 0;
        uint256 platinumCount = 0;
        uint256 silverCount = 0;
        uint256 copperCount = 0;

        for (uint256 i=0; i<_userTokens[user].length; i++) {
            METAL type_ = _getMetalType(_userTokens[user][i]);
            if (type_ == METAL.GOLD) goldCount++;
            else if (type_ == METAL.PLATINUM) platinumCount++;
            else if (type_ == METAL.SILVER) silverCount++;
            else copperCount++;
        }

        return (goldCount, platinumCount, silverCount, copperCount);
    }

    // @Set token level metadata.
    function uri(uint256 tokenId) public override(ERC1155, ERC1155URIStorage) view returns (string memory) {
        return ERC1155URIStorage.uri(tokenId);
    }

    // @Deposit ETH to contract
    function deposit() external payable {
        emit Deposit(msg.value);
    }

    // @Withdraw ETH from contract to owners address
    function withdrawAll() external onlyOwner {
        uint256 balance = address(this).balance;
        require(balance > 0);
        _withdraw(owner(), address(this).balance);

        emit WithdrawAll(balance);
    }

    // @Native coin transfer function
    function _withdraw(address _address, uint256 _amount) private {
        (bool success, ) = _address.call{value: _amount}("");
        require(success, "Transfer failed!");
    }

    /** @dev EIP2981 royalties implementation. */

    // Maintain flexibility to modify royalties recipient (could also add basis points).
    function _setRoyalties(address newRecipient, uint256 royaltyPoint) internal {
        require(newRecipient != address(0), "Royalties: new recipient is the zero address");
        require(royaltyPoint >= 0 && royaltyPoint <10000, "Royalty point should be between 0 and 100");
        _recipient = newRecipient;
        _royaltyPoint = royaltyPoint;
    }

    function setRoyalties(address newRecipient, uint256 royaltyPoint) external onlyOwner {
        _setRoyalties(newRecipient, royaltyPoint);
    }

    // EIP2981 standard royalties return.
    function royaltyInfo(uint256 _tokenId, uint256 _salePrice)

        external

        view

        override

        returns (address receiver, uint256 royaltyAmount)

    {
        require(_tokenId >= 0, "Token id should be bigger than 0");
        return (_recipient, (_salePrice * _royaltyPoint) / 10000);
    }

    // EIP2981 standard Interface return. Adds to ERC1155 and ERC165 Interface returns.
    function supportsInterface(bytes4 interfaceId)

        public

        view

        virtual

        override(ERC1155, IERC165)

        returns (bool)

    {
        return (interfaceId == type(IERC2981).interfaceId ||
            super.supportsInterface(interfaceId));
    }
}