File size: 141,686 Bytes
f998fcd
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
{
  "language": "Solidity",
  "sources": {
    "@openzeppelin/contracts/access/AccessControl.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (access/AccessControl.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IAccessControl.sol\";\nimport \"../utils/Context.sol\";\nimport \"../utils/Strings.sol\";\nimport \"../utils/introspection/ERC165.sol\";\n\n/**\n * @dev Contract module that allows children to implement role-based access\n * control mechanisms. This is a lightweight version that doesn't allow enumerating role\n * members except through off-chain means by accessing the contract event logs. Some\n * applications may benefit from on-chain enumerability, for those cases see\n * {AccessControlEnumerable}.\n *\n * Roles are referred to by their `bytes32` identifier. These should be exposed\n * in the external API and be unique. The best way to achieve this is by\n * using `public constant` hash digests:\n *\n * ```\n * bytes32 public constant MY_ROLE = keccak256(\"MY_ROLE\");\n * ```\n *\n * Roles can be used to represent a set of permissions. To restrict access to a\n * function call, use {hasRole}:\n *\n * ```\n * function foo() public {\n *     require(hasRole(MY_ROLE, msg.sender));\n *     ...\n * }\n * ```\n *\n * Roles can be granted and revoked dynamically via the {grantRole} and\n * {revokeRole} functions. Each role has an associated admin role, and only\n * accounts that have a role's admin role can call {grantRole} and {revokeRole}.\n *\n * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means\n * that only accounts with this role will be able to grant or revoke other\n * roles. More complex role relationships can be created by using\n * {_setRoleAdmin}.\n *\n * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to\n * grant and revoke this role. Extra precautions should be taken to secure\n * accounts that have been granted it.\n */\nabstract contract AccessControl is Context, IAccessControl, ERC165 {\n    struct RoleData {\n        mapping(address => bool) members;\n        bytes32 adminRole;\n    }\n\n    mapping(bytes32 => RoleData) private _roles;\n\n    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;\n\n    /**\n     * @dev Modifier that checks that an account has a specific role. Reverts\n     * with a standardized message including the required role.\n     *\n     * The format of the revert reason is given by the following regular expression:\n     *\n     *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/\n     *\n     * _Available since v4.1._\n     */\n    modifier onlyRole(bytes32 role) {\n        _checkRole(role);\n        _;\n    }\n\n    /**\n     * @dev See {IERC165-supportsInterface}.\n     */\n    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n        return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);\n    }\n\n    /**\n     * @dev Returns `true` if `account` has been granted `role`.\n     */\n    function hasRole(bytes32 role, address account) public view virtual override returns (bool) {\n        return _roles[role].members[account];\n    }\n\n    /**\n     * @dev Revert with a standard message if `_msgSender()` is missing `role`.\n     * Overriding this function changes the behavior of the {onlyRole} modifier.\n     *\n     * Format of the revert message is described in {_checkRole}.\n     *\n     * _Available since v4.6._\n     */\n    function _checkRole(bytes32 role) internal view virtual {\n        _checkRole(role, _msgSender());\n    }\n\n    /**\n     * @dev Revert with a standard message if `account` is missing `role`.\n     *\n     * The format of the revert reason is given by the following regular expression:\n     *\n     *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/\n     */\n    function _checkRole(bytes32 role, address account) internal view virtual {\n        if (!hasRole(role, account)) {\n            revert(\n                string(\n                    abi.encodePacked(\n                        \"AccessControl: account \",\n                        Strings.toHexString(account),\n                        \" is missing role \",\n                        Strings.toHexString(uint256(role), 32)\n                    )\n                )\n            );\n        }\n    }\n\n    /**\n     * @dev Returns the admin role that controls `role`. See {grantRole} and\n     * {revokeRole}.\n     *\n     * To change a role's admin, use {_setRoleAdmin}.\n     */\n    function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {\n        return _roles[role].adminRole;\n    }\n\n    /**\n     * @dev Grants `role` to `account`.\n     *\n     * If `account` had not been already granted `role`, emits a {RoleGranted}\n     * event.\n     *\n     * Requirements:\n     *\n     * - the caller must have ``role``'s admin role.\n     *\n     * May emit a {RoleGranted} event.\n     */\n    function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {\n        _grantRole(role, account);\n    }\n\n    /**\n     * @dev Revokes `role` from `account`.\n     *\n     * If `account` had been granted `role`, emits a {RoleRevoked} event.\n     *\n     * Requirements:\n     *\n     * - the caller must have ``role``'s admin role.\n     *\n     * May emit a {RoleRevoked} event.\n     */\n    function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {\n        _revokeRole(role, account);\n    }\n\n    /**\n     * @dev Revokes `role` from the calling account.\n     *\n     * Roles are often managed via {grantRole} and {revokeRole}: this function's\n     * purpose is to provide a mechanism for accounts to lose their privileges\n     * if they are compromised (such as when a trusted device is misplaced).\n     *\n     * If the calling account had been revoked `role`, emits a {RoleRevoked}\n     * event.\n     *\n     * Requirements:\n     *\n     * - the caller must be `account`.\n     *\n     * May emit a {RoleRevoked} event.\n     */\n    function renounceRole(bytes32 role, address account) public virtual override {\n        require(account == _msgSender(), \"AccessControl: can only renounce roles for self\");\n\n        _revokeRole(role, account);\n    }\n\n    /**\n     * @dev Grants `role` to `account`.\n     *\n     * If `account` had not been already granted `role`, emits a {RoleGranted}\n     * event. Note that unlike {grantRole}, this function doesn't perform any\n     * checks on the calling account.\n     *\n     * May emit a {RoleGranted} event.\n     *\n     * [WARNING]\n     * ====\n     * This function should only be called from the constructor when setting\n     * up the initial roles for the system.\n     *\n     * Using this function in any other way is effectively circumventing the admin\n     * system imposed by {AccessControl}.\n     * ====\n     *\n     * NOTE: This function is deprecated in favor of {_grantRole}.\n     */\n    function _setupRole(bytes32 role, address account) internal virtual {\n        _grantRole(role, account);\n    }\n\n    /**\n     * @dev Sets `adminRole` as ``role``'s admin role.\n     *\n     * Emits a {RoleAdminChanged} event.\n     */\n    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {\n        bytes32 previousAdminRole = getRoleAdmin(role);\n        _roles[role].adminRole = adminRole;\n        emit RoleAdminChanged(role, previousAdminRole, adminRole);\n    }\n\n    /**\n     * @dev Grants `role` to `account`.\n     *\n     * Internal function without access restriction.\n     *\n     * May emit a {RoleGranted} event.\n     */\n    function _grantRole(bytes32 role, address account) internal virtual {\n        if (!hasRole(role, account)) {\n            _roles[role].members[account] = true;\n            emit RoleGranted(role, account, _msgSender());\n        }\n    }\n\n    /**\n     * @dev Revokes `role` from `account`.\n     *\n     * Internal function without access restriction.\n     *\n     * May emit a {RoleRevoked} event.\n     */\n    function _revokeRole(bytes32 role, address account) internal virtual {\n        if (hasRole(role, account)) {\n            _roles[role].members[account] = false;\n            emit RoleRevoked(role, account, _msgSender());\n        }\n    }\n}\n"
    },
    "@openzeppelin/contracts/access/AccessControlEnumerable.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.5.0) (access/AccessControlEnumerable.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IAccessControlEnumerable.sol\";\nimport \"./AccessControl.sol\";\nimport \"../utils/structs/EnumerableSet.sol\";\n\n/**\n * @dev Extension of {AccessControl} that allows enumerating the members of each role.\n */\nabstract contract AccessControlEnumerable is IAccessControlEnumerable, AccessControl {\n    using EnumerableSet for EnumerableSet.AddressSet;\n\n    mapping(bytes32 => EnumerableSet.AddressSet) private _roleMembers;\n\n    /**\n     * @dev See {IERC165-supportsInterface}.\n     */\n    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n        return interfaceId == type(IAccessControlEnumerable).interfaceId || super.supportsInterface(interfaceId);\n    }\n\n    /**\n     * @dev Returns one of the accounts that have `role`. `index` must be a\n     * value between 0 and {getRoleMemberCount}, non-inclusive.\n     *\n     * Role bearers are not sorted in any particular way, and their ordering may\n     * change at any point.\n     *\n     * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure\n     * you perform all queries on the same block. See the following\n     * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]\n     * for more information.\n     */\n    function getRoleMember(bytes32 role, uint256 index) public view virtual override returns (address) {\n        return _roleMembers[role].at(index);\n    }\n\n    /**\n     * @dev Returns the number of accounts that have `role`. Can be used\n     * together with {getRoleMember} to enumerate all bearers of a role.\n     */\n    function getRoleMemberCount(bytes32 role) public view virtual override returns (uint256) {\n        return _roleMembers[role].length();\n    }\n\n    /**\n     * @dev Overload {_grantRole} to track enumerable memberships\n     */\n    function _grantRole(bytes32 role, address account) internal virtual override {\n        super._grantRole(role, account);\n        _roleMembers[role].add(account);\n    }\n\n    /**\n     * @dev Overload {_revokeRole} to track enumerable memberships\n     */\n    function _revokeRole(bytes32 role, address account) internal virtual override {\n        super._revokeRole(role, account);\n        _roleMembers[role].remove(account);\n    }\n}\n"
    },
    "@openzeppelin/contracts/access/IAccessControl.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev External interface of AccessControl declared to support ERC165 detection.\n */\ninterface IAccessControl {\n    /**\n     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`\n     *\n     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite\n     * {RoleAdminChanged} not being emitted signaling this.\n     *\n     * _Available since v3.1._\n     */\n    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);\n\n    /**\n     * @dev Emitted when `account` is granted `role`.\n     *\n     * `sender` is the account that originated the contract call, an admin role\n     * bearer except when using {AccessControl-_setupRole}.\n     */\n    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);\n\n    /**\n     * @dev Emitted when `account` is revoked `role`.\n     *\n     * `sender` is the account that originated the contract call:\n     *   - if using `revokeRole`, it is the admin role bearer\n     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)\n     */\n    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);\n\n    /**\n     * @dev Returns `true` if `account` has been granted `role`.\n     */\n    function hasRole(bytes32 role, address account) external view returns (bool);\n\n    /**\n     * @dev Returns the admin role that controls `role`. See {grantRole} and\n     * {revokeRole}.\n     *\n     * To change a role's admin, use {AccessControl-_setRoleAdmin}.\n     */\n    function getRoleAdmin(bytes32 role) external view returns (bytes32);\n\n    /**\n     * @dev Grants `role` to `account`.\n     *\n     * If `account` had not been already granted `role`, emits a {RoleGranted}\n     * event.\n     *\n     * Requirements:\n     *\n     * - the caller must have ``role``'s admin role.\n     */\n    function grantRole(bytes32 role, address account) external;\n\n    /**\n     * @dev Revokes `role` from `account`.\n     *\n     * If `account` had been granted `role`, emits a {RoleRevoked} event.\n     *\n     * Requirements:\n     *\n     * - the caller must have ``role``'s admin role.\n     */\n    function revokeRole(bytes32 role, address account) external;\n\n    /**\n     * @dev Revokes `role` from the calling account.\n     *\n     * Roles are often managed via {grantRole} and {revokeRole}: this function's\n     * purpose is to provide a mechanism for accounts to lose their privileges\n     * if they are compromised (such as when a trusted device is misplaced).\n     *\n     * If the calling account had been granted `role`, emits a {RoleRevoked}\n     * event.\n     *\n     * Requirements:\n     *\n     * - the caller must be `account`.\n     */\n    function renounceRole(bytes32 role, address account) external;\n}\n"
    },
    "@openzeppelin/contracts/access/IAccessControlEnumerable.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (access/IAccessControlEnumerable.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IAccessControl.sol\";\n\n/**\n * @dev External interface of AccessControlEnumerable declared to support ERC165 detection.\n */\ninterface IAccessControlEnumerable is IAccessControl {\n    /**\n     * @dev Returns one of the accounts that have `role`. `index` must be a\n     * value between 0 and {getRoleMemberCount}, non-inclusive.\n     *\n     * Role bearers are not sorted in any particular way, and their ordering may\n     * change at any point.\n     *\n     * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure\n     * you perform all queries on the same block. See the following\n     * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]\n     * for more information.\n     */\n    function getRoleMember(bytes32 role, uint256 index) external view returns (address);\n\n    /**\n     * @dev Returns the number of accounts that have `role`. Can be used\n     * together with {getRoleMember} to enumerate all bearers of a role.\n     */\n    function getRoleMemberCount(bytes32 role) external view returns (uint256);\n}\n"
    },
    "@openzeppelin/contracts/security/Pausable.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../utils/Context.sol\";\n\n/**\n * @dev Contract module which allows children to implement an emergency stop\n * mechanism that can be triggered by an authorized account.\n *\n * This module is used through inheritance. It will make available the\n * modifiers `whenNotPaused` and `whenPaused`, which can be applied to\n * the functions of your contract. Note that they will not be pausable by\n * simply including this module, only once the modifiers are put in place.\n */\nabstract contract Pausable is Context {\n    /**\n     * @dev Emitted when the pause is triggered by `account`.\n     */\n    event Paused(address account);\n\n    /**\n     * @dev Emitted when the pause is lifted by `account`.\n     */\n    event Unpaused(address account);\n\n    bool private _paused;\n\n    /**\n     * @dev Initializes the contract in unpaused state.\n     */\n    constructor() {\n        _paused = false;\n    }\n\n    /**\n     * @dev Modifier to make a function callable only when the contract is not paused.\n     *\n     * Requirements:\n     *\n     * - The contract must not be paused.\n     */\n    modifier whenNotPaused() {\n        _requireNotPaused();\n        _;\n    }\n\n    /**\n     * @dev Modifier to make a function callable only when the contract is paused.\n     *\n     * Requirements:\n     *\n     * - The contract must be paused.\n     */\n    modifier whenPaused() {\n        _requirePaused();\n        _;\n    }\n\n    /**\n     * @dev Returns true if the contract is paused, and false otherwise.\n     */\n    function paused() public view virtual returns (bool) {\n        return _paused;\n    }\n\n    /**\n     * @dev Throws if the contract is paused.\n     */\n    function _requireNotPaused() internal view virtual {\n        require(!paused(), \"Pausable: paused\");\n    }\n\n    /**\n     * @dev Throws if the contract is not paused.\n     */\n    function _requirePaused() internal view virtual {\n        require(paused(), \"Pausable: not paused\");\n    }\n\n    /**\n     * @dev Triggers stopped state.\n     *\n     * Requirements:\n     *\n     * - The contract must not be paused.\n     */\n    function _pause() internal virtual whenNotPaused {\n        _paused = true;\n        emit Paused(_msgSender());\n    }\n\n    /**\n     * @dev Returns to normal state.\n     *\n     * Requirements:\n     *\n     * - The contract must be paused.\n     */\n    function _unpause() internal virtual whenPaused {\n        _paused = false;\n        emit Unpaused(_msgSender());\n    }\n}\n"
    },
    "@openzeppelin/contracts/token/ERC20/extensions/draft-IERC20Permit.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in\n * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].\n *\n * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by\n * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't\n * need to send a transaction, and thus is not required to hold Ether at all.\n */\ninterface IERC20Permit {\n    /**\n     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,\n     * given ``owner``'s signed approval.\n     *\n     * IMPORTANT: The same issues {IERC20-approve} has related to transaction\n     * ordering also apply here.\n     *\n     * Emits an {Approval} event.\n     *\n     * Requirements:\n     *\n     * - `spender` cannot be the zero address.\n     * - `deadline` must be a timestamp in the future.\n     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`\n     * over the EIP712-formatted function arguments.\n     * - the signature must use ``owner``'s current nonce (see {nonces}).\n     *\n     * For more information on the signature format, see the\n     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP\n     * section].\n     */\n    function permit(\n        address owner,\n        address spender,\n        uint256 value,\n        uint256 deadline,\n        uint8 v,\n        bytes32 r,\n        bytes32 s\n    ) external;\n\n    /**\n     * @dev Returns the current nonce for `owner`. This value must be\n     * included whenever a signature is generated for {permit}.\n     *\n     * Every successful call to {permit} increases ``owner``'s nonce by one. This\n     * prevents a signature from being used multiple times.\n     */\n    function nonces(address owner) external view returns (uint256);\n\n    /**\n     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.\n     */\n    // solhint-disable-next-line func-name-mixedcase\n    function DOMAIN_SEPARATOR() external view returns (bytes32);\n}\n"
    },
    "@openzeppelin/contracts/token/ERC20/IERC20.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC20 standard as defined in the EIP.\n */\ninterface IERC20 {\n    /**\n     * @dev Emitted when `value` tokens are moved from one account (`from`) to\n     * another (`to`).\n     *\n     * Note that `value` may be zero.\n     */\n    event Transfer(address indexed from, address indexed to, uint256 value);\n\n    /**\n     * @dev Emitted when the allowance of a `spender` for an `owner` is set by\n     * a call to {approve}. `value` is the new allowance.\n     */\n    event Approval(address indexed owner, address indexed spender, uint256 value);\n\n    /**\n     * @dev Returns the amount of tokens in existence.\n     */\n    function totalSupply() external view returns (uint256);\n\n    /**\n     * @dev Returns the amount of tokens owned by `account`.\n     */\n    function balanceOf(address account) external view returns (uint256);\n\n    /**\n     * @dev Moves `amount` tokens from the caller's account to `to`.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transfer(address to, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Returns the remaining number of tokens that `spender` will be\n     * allowed to spend on behalf of `owner` through {transferFrom}. This is\n     * zero by default.\n     *\n     * This value changes when {approve} or {transferFrom} are called.\n     */\n    function allowance(address owner, address spender) external view returns (uint256);\n\n    /**\n     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * IMPORTANT: Beware that changing an allowance with this method brings the risk\n     * that someone may use both the old and the new allowance by unfortunate\n     * transaction ordering. One possible solution to mitigate this race\n     * condition is to first reduce the spender's allowance to 0 and set the\n     * desired value afterwards:\n     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729\n     *\n     * Emits an {Approval} event.\n     */\n    function approve(address spender, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Moves `amount` tokens from `from` to `to` using the\n     * allowance mechanism. `amount` is then deducted from the caller's\n     * allowance.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transferFrom(\n        address from,\n        address to,\n        uint256 amount\n    ) external returns (bool);\n}\n"
    },
    "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/utils/SafeERC20.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../IERC20.sol\";\nimport \"../extensions/draft-IERC20Permit.sol\";\nimport \"../../../utils/Address.sol\";\n\n/**\n * @title SafeERC20\n * @dev Wrappers around ERC20 operations that throw on failure (when the token\n * contract returns false). Tokens that return no value (and instead revert or\n * throw on failure) are also supported, non-reverting calls are assumed to be\n * successful.\n * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,\n * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.\n */\nlibrary SafeERC20 {\n    using Address for address;\n\n    function safeTransfer(\n        IERC20 token,\n        address to,\n        uint256 value\n    ) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));\n    }\n\n    function safeTransferFrom(\n        IERC20 token,\n        address from,\n        address to,\n        uint256 value\n    ) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));\n    }\n\n    /**\n     * @dev Deprecated. This function has issues similar to the ones found in\n     * {IERC20-approve}, and its usage is discouraged.\n     *\n     * Whenever possible, use {safeIncreaseAllowance} and\n     * {safeDecreaseAllowance} instead.\n     */\n    function safeApprove(\n        IERC20 token,\n        address spender,\n        uint256 value\n    ) internal {\n        // safeApprove should only be called when setting an initial allowance,\n        // or when resetting it to zero. To increase and decrease it, use\n        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'\n        require(\n            (value == 0) || (token.allowance(address(this), spender) == 0),\n            \"SafeERC20: approve from non-zero to non-zero allowance\"\n        );\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));\n    }\n\n    function safeIncreaseAllowance(\n        IERC20 token,\n        address spender,\n        uint256 value\n    ) internal {\n        uint256 newAllowance = token.allowance(address(this), spender) + value;\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n    }\n\n    function safeDecreaseAllowance(\n        IERC20 token,\n        address spender,\n        uint256 value\n    ) internal {\n        unchecked {\n            uint256 oldAllowance = token.allowance(address(this), spender);\n            require(oldAllowance >= value, \"SafeERC20: decreased allowance below zero\");\n            uint256 newAllowance = oldAllowance - value;\n            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n        }\n    }\n\n    function safePermit(\n        IERC20Permit token,\n        address owner,\n        address spender,\n        uint256 value,\n        uint256 deadline,\n        uint8 v,\n        bytes32 r,\n        bytes32 s\n    ) internal {\n        uint256 nonceBefore = token.nonces(owner);\n        token.permit(owner, spender, value, deadline, v, r, s);\n        uint256 nonceAfter = token.nonces(owner);\n        require(nonceAfter == nonceBefore + 1, \"SafeERC20: permit did not succeed\");\n    }\n\n    /**\n     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement\n     * on the return value: the return value is optional (but if data is returned, it must not be false).\n     * @param token The token targeted by the call.\n     * @param data The call data (encoded using abi.encode or one of its variants).\n     */\n    function _callOptionalReturn(IERC20 token, bytes memory data) private {\n        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since\n        // we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that\n        // the target address contains contract code and also asserts for success in the low-level call.\n\n        bytes memory returndata = address(token).functionCall(data, \"SafeERC20: low-level call failed\");\n        if (returndata.length > 0) {\n            // Return data is optional\n            require(abi.decode(returndata, (bool)), \"SafeERC20: ERC20 operation did not succeed\");\n        }\n    }\n}\n"
    },
    "@openzeppelin/contracts/token/ERC721/ERC721.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.2) (token/ERC721/ERC721.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IERC721.sol\";\nimport \"./IERC721Receiver.sol\";\nimport \"./extensions/IERC721Metadata.sol\";\nimport \"../../utils/Address.sol\";\nimport \"../../utils/Context.sol\";\nimport \"../../utils/Strings.sol\";\nimport \"../../utils/introspection/ERC165.sol\";\n\n/**\n * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including\n * the Metadata extension, but not including the Enumerable extension, which is available separately as\n * {ERC721Enumerable}.\n */\ncontract ERC721 is Context, ERC165, IERC721, IERC721Metadata {\n    using Address for address;\n    using Strings for uint256;\n\n    // Token name\n    string private _name;\n\n    // Token symbol\n    string private _symbol;\n\n    // Mapping from token ID to owner address\n    mapping(uint256 => address) private _owners;\n\n    // Mapping owner address to token count\n    mapping(address => uint256) private _balances;\n\n    // Mapping from token ID to approved address\n    mapping(uint256 => address) private _tokenApprovals;\n\n    // Mapping from owner to operator approvals\n    mapping(address => mapping(address => bool)) private _operatorApprovals;\n\n    /**\n     * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.\n     */\n    constructor(string memory name_, string memory symbol_) {\n        _name = name_;\n        _symbol = symbol_;\n    }\n\n    /**\n     * @dev See {IERC165-supportsInterface}.\n     */\n    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {\n        return\n            interfaceId == type(IERC721).interfaceId ||\n            interfaceId == type(IERC721Metadata).interfaceId ||\n            super.supportsInterface(interfaceId);\n    }\n\n    /**\n     * @dev See {IERC721-balanceOf}.\n     */\n    function balanceOf(address owner) public view virtual override returns (uint256) {\n        require(owner != address(0), \"ERC721: address zero is not a valid owner\");\n        return _balances[owner];\n    }\n\n    /**\n     * @dev See {IERC721-ownerOf}.\n     */\n    function ownerOf(uint256 tokenId) public view virtual override returns (address) {\n        address owner = _ownerOf(tokenId);\n        require(owner != address(0), \"ERC721: invalid token ID\");\n        return owner;\n    }\n\n    /**\n     * @dev See {IERC721Metadata-name}.\n     */\n    function name() public view virtual override returns (string memory) {\n        return _name;\n    }\n\n    /**\n     * @dev See {IERC721Metadata-symbol}.\n     */\n    function symbol() public view virtual override returns (string memory) {\n        return _symbol;\n    }\n\n    /**\n     * @dev See {IERC721Metadata-tokenURI}.\n     */\n    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {\n        _requireMinted(tokenId);\n\n        string memory baseURI = _baseURI();\n        return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : \"\";\n    }\n\n    /**\n     * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each\n     * token will be the concatenation of the `baseURI` and the `tokenId`. Empty\n     * by default, can be overridden in child contracts.\n     */\n    function _baseURI() internal view virtual returns (string memory) {\n        return \"\";\n    }\n\n    /**\n     * @dev See {IERC721-approve}.\n     */\n    function approve(address to, uint256 tokenId) public virtual override {\n        address owner = ERC721.ownerOf(tokenId);\n        require(to != owner, \"ERC721: approval to current owner\");\n\n        require(\n            _msgSender() == owner || isApprovedForAll(owner, _msgSender()),\n            \"ERC721: approve caller is not token owner or approved for all\"\n        );\n\n        _approve(to, tokenId);\n    }\n\n    /**\n     * @dev See {IERC721-getApproved}.\n     */\n    function getApproved(uint256 tokenId) public view virtual override returns (address) {\n        _requireMinted(tokenId);\n\n        return _tokenApprovals[tokenId];\n    }\n\n    /**\n     * @dev See {IERC721-setApprovalForAll}.\n     */\n    function setApprovalForAll(address operator, bool approved) public virtual override {\n        _setApprovalForAll(_msgSender(), operator, approved);\n    }\n\n    /**\n     * @dev See {IERC721-isApprovedForAll}.\n     */\n    function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {\n        return _operatorApprovals[owner][operator];\n    }\n\n    /**\n     * @dev See {IERC721-transferFrom}.\n     */\n    function transferFrom(\n        address from,\n        address to,\n        uint256 tokenId\n    ) public virtual override {\n        //solhint-disable-next-line max-line-length\n        require(_isApprovedOrOwner(_msgSender(), tokenId), \"ERC721: caller is not token owner or approved\");\n\n        _transfer(from, to, tokenId);\n    }\n\n    /**\n     * @dev See {IERC721-safeTransferFrom}.\n     */\n    function safeTransferFrom(\n        address from,\n        address to,\n        uint256 tokenId\n    ) public virtual override {\n        safeTransferFrom(from, to, tokenId, \"\");\n    }\n\n    /**\n     * @dev See {IERC721-safeTransferFrom}.\n     */\n    function safeTransferFrom(\n        address from,\n        address to,\n        uint256 tokenId,\n        bytes memory data\n    ) public virtual override {\n        require(_isApprovedOrOwner(_msgSender(), tokenId), \"ERC721: caller is not token owner or approved\");\n        _safeTransfer(from, to, tokenId, data);\n    }\n\n    /**\n     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients\n     * are aware of the ERC721 protocol to prevent tokens from being forever locked.\n     *\n     * `data` is additional data, it has no specified format and it is sent in call to `to`.\n     *\n     * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.\n     * implement alternative mechanisms to perform token transfer, such as signature-based.\n     *\n     * Requirements:\n     *\n     * - `from` cannot be the zero address.\n     * - `to` cannot be the zero address.\n     * - `tokenId` token must exist and be owned by `from`.\n     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n     *\n     * Emits a {Transfer} event.\n     */\n    function _safeTransfer(\n        address from,\n        address to,\n        uint256 tokenId,\n        bytes memory data\n    ) internal virtual {\n        _transfer(from, to, tokenId);\n        require(_checkOnERC721Received(from, to, tokenId, data), \"ERC721: transfer to non ERC721Receiver implementer\");\n    }\n\n    /**\n     * @dev Returns the owner of the `tokenId`. Does NOT revert if token doesn't exist\n     */\n    function _ownerOf(uint256 tokenId) internal view virtual returns (address) {\n        return _owners[tokenId];\n    }\n\n    /**\n     * @dev Returns whether `tokenId` exists.\n     *\n     * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.\n     *\n     * Tokens start existing when they are minted (`_mint`),\n     * and stop existing when they are burned (`_burn`).\n     */\n    function _exists(uint256 tokenId) internal view virtual returns (bool) {\n        return _ownerOf(tokenId) != address(0);\n    }\n\n    /**\n     * @dev Returns whether `spender` is allowed to manage `tokenId`.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must exist.\n     */\n    function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {\n        address owner = ERC721.ownerOf(tokenId);\n        return (spender == owner || isApprovedForAll(owner, spender) || getApproved(tokenId) == spender);\n    }\n\n    /**\n     * @dev Safely mints `tokenId` and transfers it to `to`.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must not exist.\n     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n     *\n     * Emits a {Transfer} event.\n     */\n    function _safeMint(address to, uint256 tokenId) internal virtual {\n        _safeMint(to, tokenId, \"\");\n    }\n\n    /**\n     * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is\n     * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.\n     */\n    function _safeMint(\n        address to,\n        uint256 tokenId,\n        bytes memory data\n    ) internal virtual {\n        _mint(to, tokenId);\n        require(\n            _checkOnERC721Received(address(0), to, tokenId, data),\n            \"ERC721: transfer to non ERC721Receiver implementer\"\n        );\n    }\n\n    /**\n     * @dev Mints `tokenId` and transfers it to `to`.\n     *\n     * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible\n     *\n     * Requirements:\n     *\n     * - `tokenId` must not exist.\n     * - `to` cannot be the zero address.\n     *\n     * Emits a {Transfer} event.\n     */\n    function _mint(address to, uint256 tokenId) internal virtual {\n        require(to != address(0), \"ERC721: mint to the zero address\");\n        require(!_exists(tokenId), \"ERC721: token already minted\");\n\n        _beforeTokenTransfer(address(0), to, tokenId, 1);\n\n        // Check that tokenId was not minted by `_beforeTokenTransfer` hook\n        require(!_exists(tokenId), \"ERC721: token already minted\");\n\n        unchecked {\n            // Will not overflow unless all 2**256 token ids are minted to the same owner.\n            // Given that tokens are minted one by one, it is impossible in practice that\n            // this ever happens. Might change if we allow batch minting.\n            // The ERC fails to describe this case.\n            _balances[to] += 1;\n        }\n\n        _owners[tokenId] = to;\n\n        emit Transfer(address(0), to, tokenId);\n\n        _afterTokenTransfer(address(0), to, tokenId, 1);\n    }\n\n    /**\n     * @dev Destroys `tokenId`.\n     * The approval is cleared when the token is burned.\n     * This is an internal function that does not check if the sender is authorized to operate on the token.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must exist.\n     *\n     * Emits a {Transfer} event.\n     */\n    function _burn(uint256 tokenId) internal virtual {\n        address owner = ERC721.ownerOf(tokenId);\n\n        _beforeTokenTransfer(owner, address(0), tokenId, 1);\n\n        // Update ownership in case tokenId was transferred by `_beforeTokenTransfer` hook\n        owner = ERC721.ownerOf(tokenId);\n\n        // Clear approvals\n        delete _tokenApprovals[tokenId];\n\n        unchecked {\n            // Cannot overflow, as that would require more tokens to be burned/transferred\n            // out than the owner initially received through minting and transferring in.\n            _balances[owner] -= 1;\n        }\n        delete _owners[tokenId];\n\n        emit Transfer(owner, address(0), tokenId);\n\n        _afterTokenTransfer(owner, address(0), tokenId, 1);\n    }\n\n    /**\n     * @dev Transfers `tokenId` from `from` to `to`.\n     *  As opposed to {transferFrom}, this imposes no restrictions on msg.sender.\n     *\n     * Requirements:\n     *\n     * - `to` cannot be the zero address.\n     * - `tokenId` token must be owned by `from`.\n     *\n     * Emits a {Transfer} event.\n     */\n    function _transfer(\n        address from,\n        address to,\n        uint256 tokenId\n    ) internal virtual {\n        require(ERC721.ownerOf(tokenId) == from, \"ERC721: transfer from incorrect owner\");\n        require(to != address(0), \"ERC721: transfer to the zero address\");\n\n        _beforeTokenTransfer(from, to, tokenId, 1);\n\n        // Check that tokenId was not transferred by `_beforeTokenTransfer` hook\n        require(ERC721.ownerOf(tokenId) == from, \"ERC721: transfer from incorrect owner\");\n\n        // Clear approvals from the previous owner\n        delete _tokenApprovals[tokenId];\n\n        unchecked {\n            // `_balances[from]` cannot overflow for the same reason as described in `_burn`:\n            // `from`'s balance is the number of token held, which is at least one before the current\n            // transfer.\n            // `_balances[to]` could overflow in the conditions described in `_mint`. That would require\n            // all 2**256 token ids to be minted, which in practice is impossible.\n            _balances[from] -= 1;\n            _balances[to] += 1;\n        }\n        _owners[tokenId] = to;\n\n        emit Transfer(from, to, tokenId);\n\n        _afterTokenTransfer(from, to, tokenId, 1);\n    }\n\n    /**\n     * @dev Approve `to` to operate on `tokenId`\n     *\n     * Emits an {Approval} event.\n     */\n    function _approve(address to, uint256 tokenId) internal virtual {\n        _tokenApprovals[tokenId] = to;\n        emit Approval(ERC721.ownerOf(tokenId), to, tokenId);\n    }\n\n    /**\n     * @dev Approve `operator` to operate on all of `owner` tokens\n     *\n     * Emits an {ApprovalForAll} event.\n     */\n    function _setApprovalForAll(\n        address owner,\n        address operator,\n        bool approved\n    ) internal virtual {\n        require(owner != operator, \"ERC721: approve to caller\");\n        _operatorApprovals[owner][operator] = approved;\n        emit ApprovalForAll(owner, operator, approved);\n    }\n\n    /**\n     * @dev Reverts if the `tokenId` has not been minted yet.\n     */\n    function _requireMinted(uint256 tokenId) internal view virtual {\n        require(_exists(tokenId), \"ERC721: invalid token ID\");\n    }\n\n    /**\n     * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.\n     * The call is not executed if the target address is not a contract.\n     *\n     * @param from address representing the previous owner of the given token ID\n     * @param to target address that will receive the tokens\n     * @param tokenId uint256 ID of the token to be transferred\n     * @param data bytes optional data to send along with the call\n     * @return bool whether the call correctly returned the expected magic value\n     */\n    function _checkOnERC721Received(\n        address from,\n        address to,\n        uint256 tokenId,\n        bytes memory data\n    ) private returns (bool) {\n        if (to.isContract()) {\n            try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, data) returns (bytes4 retval) {\n                return retval == IERC721Receiver.onERC721Received.selector;\n            } catch (bytes memory reason) {\n                if (reason.length == 0) {\n                    revert(\"ERC721: transfer to non ERC721Receiver implementer\");\n                } else {\n                    /// @solidity memory-safe-assembly\n                    assembly {\n                        revert(add(32, reason), mload(reason))\n                    }\n                }\n            }\n        } else {\n            return true;\n        }\n    }\n\n    /**\n     * @dev Hook that is called before any token transfer. This includes minting and burning. If {ERC721Consecutive} is\n     * used, the hook may be called as part of a consecutive (batch) mint, as indicated by `batchSize` greater than 1.\n     *\n     * Calling conditions:\n     *\n     * - When `from` and `to` are both non-zero, ``from``'s tokens will be transferred to `to`.\n     * - When `from` is zero, the tokens will be minted for `to`.\n     * - When `to` is zero, ``from``'s tokens will be burned.\n     * - `from` and `to` are never both zero.\n     * - `batchSize` is non-zero.\n     *\n     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].\n     */\n    function _beforeTokenTransfer(\n        address from,\n        address to,\n        uint256 firstTokenId,\n        uint256 batchSize\n    ) internal virtual {}\n\n    /**\n     * @dev Hook that is called after any token transfer. This includes minting and burning. If {ERC721Consecutive} is\n     * used, the hook may be called as part of a consecutive (batch) mint, as indicated by `batchSize` greater than 1.\n     *\n     * Calling conditions:\n     *\n     * - When `from` and `to` are both non-zero, ``from``'s tokens were transferred to `to`.\n     * - When `from` is zero, the tokens were minted for `to`.\n     * - When `to` is zero, ``from``'s tokens were burned.\n     * - `from` and `to` are never both zero.\n     * - `batchSize` is non-zero.\n     *\n     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].\n     */\n    function _afterTokenTransfer(\n        address from,\n        address to,\n        uint256 firstTokenId,\n        uint256 batchSize\n    ) internal virtual {}\n\n    /**\n     * @dev Unsafe write access to the balances, used by extensions that \"mint\" tokens using an {ownerOf} override.\n     *\n     * WARNING: Anyone calling this MUST ensure that the balances remain consistent with the ownership. The invariant\n     * being that for any address `a` the value returned by `balanceOf(a)` must be equal to the number of tokens such\n     * that `ownerOf(tokenId)` is `a`.\n     */\n    // solhint-disable-next-line func-name-mixedcase\n    function __unsafe_increaseBalance(address account, uint256 amount) internal {\n        _balances[account] += amount;\n    }\n}\n"
    },
    "@openzeppelin/contracts/token/ERC721/extensions/ERC721Burnable.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/extensions/ERC721Burnable.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../ERC721.sol\";\nimport \"../../../utils/Context.sol\";\n\n/**\n * @title ERC721 Burnable Token\n * @dev ERC721 Token that can be burned (destroyed).\n */\nabstract contract ERC721Burnable is Context, ERC721 {\n    /**\n     * @dev Burns `tokenId`. See {ERC721-_burn}.\n     *\n     * Requirements:\n     *\n     * - The caller must own `tokenId` or be an approved operator.\n     */\n    function burn(uint256 tokenId) public virtual {\n        //solhint-disable-next-line max-line-length\n        require(_isApprovedOrOwner(_msgSender(), tokenId), \"ERC721: caller is not token owner or approved\");\n        _burn(tokenId);\n    }\n}\n"
    },
    "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/extensions/ERC721Enumerable.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../ERC721.sol\";\nimport \"./IERC721Enumerable.sol\";\n\n/**\n * @dev This implements an optional extension of {ERC721} defined in the EIP that adds\n * enumerability of all the token ids in the contract as well as all token ids owned by each\n * account.\n */\nabstract contract ERC721Enumerable is ERC721, IERC721Enumerable {\n    // Mapping from owner to list of owned token IDs\n    mapping(address => mapping(uint256 => uint256)) private _ownedTokens;\n\n    // Mapping from token ID to index of the owner tokens list\n    mapping(uint256 => uint256) private _ownedTokensIndex;\n\n    // Array with all token ids, used for enumeration\n    uint256[] private _allTokens;\n\n    // Mapping from token id to position in the allTokens array\n    mapping(uint256 => uint256) private _allTokensIndex;\n\n    /**\n     * @dev See {IERC165-supportsInterface}.\n     */\n    function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) {\n        return interfaceId == type(IERC721Enumerable).interfaceId || super.supportsInterface(interfaceId);\n    }\n\n    /**\n     * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.\n     */\n    function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) {\n        require(index < ERC721.balanceOf(owner), \"ERC721Enumerable: owner index out of bounds\");\n        return _ownedTokens[owner][index];\n    }\n\n    /**\n     * @dev See {IERC721Enumerable-totalSupply}.\n     */\n    function totalSupply() public view virtual override returns (uint256) {\n        return _allTokens.length;\n    }\n\n    /**\n     * @dev See {IERC721Enumerable-tokenByIndex}.\n     */\n    function tokenByIndex(uint256 index) public view virtual override returns (uint256) {\n        require(index < ERC721Enumerable.totalSupply(), \"ERC721Enumerable: global index out of bounds\");\n        return _allTokens[index];\n    }\n\n    /**\n     * @dev See {ERC721-_beforeTokenTransfer}.\n     */\n    function _beforeTokenTransfer(\n        address from,\n        address to,\n        uint256 firstTokenId,\n        uint256 batchSize\n    ) internal virtual override {\n        super._beforeTokenTransfer(from, to, firstTokenId, batchSize);\n\n        if (batchSize > 1) {\n            // Will only trigger during construction. Batch transferring (minting) is not available afterwards.\n            revert(\"ERC721Enumerable: consecutive transfers not supported\");\n        }\n\n        uint256 tokenId = firstTokenId;\n\n        if (from == address(0)) {\n            _addTokenToAllTokensEnumeration(tokenId);\n        } else if (from != to) {\n            _removeTokenFromOwnerEnumeration(from, tokenId);\n        }\n        if (to == address(0)) {\n            _removeTokenFromAllTokensEnumeration(tokenId);\n        } else if (to != from) {\n            _addTokenToOwnerEnumeration(to, tokenId);\n        }\n    }\n\n    /**\n     * @dev Private function to add a token to this extension's ownership-tracking data structures.\n     * @param to address representing the new owner of the given token ID\n     * @param tokenId uint256 ID of the token to be added to the tokens list of the given address\n     */\n    function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private {\n        uint256 length = ERC721.balanceOf(to);\n        _ownedTokens[to][length] = tokenId;\n        _ownedTokensIndex[tokenId] = length;\n    }\n\n    /**\n     * @dev Private function to add a token to this extension's token tracking data structures.\n     * @param tokenId uint256 ID of the token to be added to the tokens list\n     */\n    function _addTokenToAllTokensEnumeration(uint256 tokenId) private {\n        _allTokensIndex[tokenId] = _allTokens.length;\n        _allTokens.push(tokenId);\n    }\n\n    /**\n     * @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that\n     * while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for\n     * gas optimizations e.g. when performing a transfer operation (avoiding double writes).\n     * This has O(1) time complexity, but alters the order of the _ownedTokens array.\n     * @param from address representing the previous owner of the given token ID\n     * @param tokenId uint256 ID of the token to be removed from the tokens list of the given address\n     */\n    function _removeTokenFromOwnerEnumeration(address from, uint256 tokenId) private {\n        // To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and\n        // then delete the last slot (swap and pop).\n\n        uint256 lastTokenIndex = ERC721.balanceOf(from) - 1;\n        uint256 tokenIndex = _ownedTokensIndex[tokenId];\n\n        // When the token to delete is the last token, the swap operation is unnecessary\n        if (tokenIndex != lastTokenIndex) {\n            uint256 lastTokenId = _ownedTokens[from][lastTokenIndex];\n\n            _ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token\n            _ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index\n        }\n\n        // This also deletes the contents at the last position of the array\n        delete _ownedTokensIndex[tokenId];\n        delete _ownedTokens[from][lastTokenIndex];\n    }\n\n    /**\n     * @dev Private function to remove a token from this extension's token tracking data structures.\n     * This has O(1) time complexity, but alters the order of the _allTokens array.\n     * @param tokenId uint256 ID of the token to be removed from the tokens list\n     */\n    function _removeTokenFromAllTokensEnumeration(uint256 tokenId) private {\n        // To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and\n        // then delete the last slot (swap and pop).\n\n        uint256 lastTokenIndex = _allTokens.length - 1;\n        uint256 tokenIndex = _allTokensIndex[tokenId];\n\n        // When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so\n        // rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding\n        // an 'if' statement (like in _removeTokenFromOwnerEnumeration)\n        uint256 lastTokenId = _allTokens[lastTokenIndex];\n\n        _allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token\n        _allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index\n\n        // This also deletes the contents at the last position of the array\n        delete _allTokensIndex[tokenId];\n        _allTokens.pop();\n    }\n}\n"
    },
    "@openzeppelin/contracts/token/ERC721/extensions/ERC721Pausable.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.2) (token/ERC721/extensions/ERC721Pausable.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../ERC721.sol\";\nimport \"../../../security/Pausable.sol\";\n\n/**\n * @dev ERC721 token with pausable token transfers, minting and burning.\n *\n * Useful for scenarios such as preventing trades until the end of an evaluation\n * period, or having an emergency switch for freezing all token transfers in the\n * event of a large bug.\n *\n * IMPORTANT: This contract does not include public pause and unpause functions. In\n * addition to inheriting this contract, you must define both functions, invoking the\n * {Pausable-_pause} and {Pausable-_unpause} internal functions, with appropriate\n * access control, e.g. using {AccessControl} or {Ownable}. Not doing so will\n * make the contract unpausable.\n */\nabstract contract ERC721Pausable is ERC721, Pausable {\n    /**\n     * @dev See {ERC721-_beforeTokenTransfer}.\n     *\n     * Requirements:\n     *\n     * - the contract must not be paused.\n     */\n    function _beforeTokenTransfer(\n        address from,\n        address to,\n        uint256 firstTokenId,\n        uint256 batchSize\n    ) internal virtual override {\n        super._beforeTokenTransfer(from, to, firstTokenId, batchSize);\n\n        require(!paused(), \"ERC721Pausable: token transfer while paused\");\n    }\n}\n"
    },
    "@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/extensions/IERC721Enumerable.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../IERC721.sol\";\n\n/**\n * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension\n * @dev See https://eips.ethereum.org/EIPS/eip-721\n */\ninterface IERC721Enumerable is IERC721 {\n    /**\n     * @dev Returns the total amount of tokens stored by the contract.\n     */\n    function totalSupply() external view returns (uint256);\n\n    /**\n     * @dev Returns a token ID owned by `owner` at a given `index` of its token list.\n     * Use along with {balanceOf} to enumerate all of ``owner``'s tokens.\n     */\n    function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256);\n\n    /**\n     * @dev Returns a token ID at a given `index` of all the tokens stored by the contract.\n     * Use along with {totalSupply} to enumerate all tokens.\n     */\n    function tokenByIndex(uint256 index) external view returns (uint256);\n}\n"
    },
    "@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../IERC721.sol\";\n\n/**\n * @title ERC-721 Non-Fungible Token Standard, optional metadata extension\n * @dev See https://eips.ethereum.org/EIPS/eip-721\n */\ninterface IERC721Metadata is IERC721 {\n    /**\n     * @dev Returns the token collection name.\n     */\n    function name() external view returns (string memory);\n\n    /**\n     * @dev Returns the token collection symbol.\n     */\n    function symbol() external view returns (string memory);\n\n    /**\n     * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.\n     */\n    function tokenURI(uint256 tokenId) external view returns (string memory);\n}\n"
    },
    "@openzeppelin/contracts/token/ERC721/IERC721.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/IERC721.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../../utils/introspection/IERC165.sol\";\n\n/**\n * @dev Required interface of an ERC721 compliant contract.\n */\ninterface IERC721 is IERC165 {\n    /**\n     * @dev Emitted when `tokenId` token is transferred from `from` to `to`.\n     */\n    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);\n\n    /**\n     * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.\n     */\n    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);\n\n    /**\n     * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.\n     */\n    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);\n\n    /**\n     * @dev Returns the number of tokens in ``owner``'s account.\n     */\n    function balanceOf(address owner) external view returns (uint256 balance);\n\n    /**\n     * @dev Returns the owner of the `tokenId` token.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must exist.\n     */\n    function ownerOf(uint256 tokenId) external view returns (address owner);\n\n    /**\n     * @dev Safely transfers `tokenId` token from `from` to `to`.\n     *\n     * Requirements:\n     *\n     * - `from` cannot be the zero address.\n     * - `to` cannot be the zero address.\n     * - `tokenId` token must exist and be owned by `from`.\n     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.\n     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n     *\n     * Emits a {Transfer} event.\n     */\n    function safeTransferFrom(\n        address from,\n        address to,\n        uint256 tokenId,\n        bytes calldata data\n    ) external;\n\n    /**\n     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients\n     * are aware of the ERC721 protocol to prevent tokens from being forever locked.\n     *\n     * Requirements:\n     *\n     * - `from` cannot be the zero address.\n     * - `to` cannot be the zero address.\n     * - `tokenId` token must exist and be owned by `from`.\n     * - If the caller is not `from`, it must have been allowed to move this token by either {approve} or {setApprovalForAll}.\n     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n     *\n     * Emits a {Transfer} event.\n     */\n    function safeTransferFrom(\n        address from,\n        address to,\n        uint256 tokenId\n    ) external;\n\n    /**\n     * @dev Transfers `tokenId` token from `from` to `to`.\n     *\n     * WARNING: Note that the caller is responsible to confirm that the recipient is capable of receiving ERC721\n     * or else they may be permanently lost. Usage of {safeTransferFrom} prevents loss, though the caller must\n     * understand this adds an external call which potentially creates a reentrancy vulnerability.\n     *\n     * Requirements:\n     *\n     * - `from` cannot be the zero address.\n     * - `to` cannot be the zero address.\n     * - `tokenId` token must be owned by `from`.\n     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transferFrom(\n        address from,\n        address to,\n        uint256 tokenId\n    ) external;\n\n    /**\n     * @dev Gives permission to `to` to transfer `tokenId` token to another account.\n     * The approval is cleared when the token is transferred.\n     *\n     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.\n     *\n     * Requirements:\n     *\n     * - The caller must own the token or be an approved operator.\n     * - `tokenId` must exist.\n     *\n     * Emits an {Approval} event.\n     */\n    function approve(address to, uint256 tokenId) external;\n\n    /**\n     * @dev Approve or remove `operator` as an operator for the caller.\n     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.\n     *\n     * Requirements:\n     *\n     * - The `operator` cannot be the caller.\n     *\n     * Emits an {ApprovalForAll} event.\n     */\n    function setApprovalForAll(address operator, bool _approved) external;\n\n    /**\n     * @dev Returns the account approved for `tokenId` token.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must exist.\n     */\n    function getApproved(uint256 tokenId) external view returns (address operator);\n\n    /**\n     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.\n     *\n     * See {setApprovalForAll}\n     */\n    function isApprovedForAll(address owner, address operator) external view returns (bool);\n}\n"
    },
    "@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @title ERC721 token receiver interface\n * @dev Interface for any contract that wants to support safeTransfers\n * from ERC721 asset contracts.\n */\ninterface IERC721Receiver {\n    /**\n     * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}\n     * by `operator` from `from`, this function is called.\n     *\n     * It must return its Solidity selector to confirm the token transfer.\n     * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.\n     *\n     * The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.\n     */\n    function onERC721Received(\n        address operator,\n        address from,\n        uint256 tokenId,\n        bytes calldata data\n    ) external returns (bytes4);\n}\n"
    },
    "@openzeppelin/contracts/token/ERC721/utils/ERC721Holder.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC721/utils/ERC721Holder.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../IERC721Receiver.sol\";\n\n/**\n * @dev Implementation of the {IERC721Receiver} interface.\n *\n * Accepts all token transfers.\n * Make sure the contract is able to use its token with {IERC721-safeTransferFrom}, {IERC721-approve} or {IERC721-setApprovalForAll}.\n */\ncontract ERC721Holder is IERC721Receiver {\n    /**\n     * @dev See {IERC721Receiver-onERC721Received}.\n     *\n     * Always returns `IERC721Receiver.onERC721Received.selector`.\n     */\n    function onERC721Received(\n        address,\n        address,\n        uint256,\n        bytes memory\n    ) public virtual override returns (bytes4) {\n        return this.onERC721Received.selector;\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/Address.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)\n\npragma solidity ^0.8.1;\n\n/**\n * @dev Collection of functions related to the address type\n */\nlibrary Address {\n    /**\n     * @dev Returns true if `account` is a contract.\n     *\n     * [IMPORTANT]\n     * ====\n     * It is unsafe to assume that an address for which this function returns\n     * false is an externally-owned account (EOA) and not a contract.\n     *\n     * Among others, `isContract` will return false for the following\n     * types of addresses:\n     *\n     *  - an externally-owned account\n     *  - a contract in construction\n     *  - an address where a contract will be created\n     *  - an address where a contract lived, but was destroyed\n     * ====\n     *\n     * [IMPORTANT]\n     * ====\n     * You shouldn't rely on `isContract` to protect against flash loan attacks!\n     *\n     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets\n     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract\n     * constructor.\n     * ====\n     */\n    function isContract(address account) internal view returns (bool) {\n        // This method relies on extcodesize/address.code.length, which returns 0\n        // for contracts in construction, since the code is only stored at the end\n        // of the constructor execution.\n\n        return account.code.length > 0;\n    }\n\n    /**\n     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to\n     * `recipient`, forwarding all available gas and reverting on errors.\n     *\n     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost\n     * of certain opcodes, possibly making contracts go over the 2300 gas limit\n     * imposed by `transfer`, making them unable to receive funds via\n     * `transfer`. {sendValue} removes this limitation.\n     *\n     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].\n     *\n     * IMPORTANT: because control is transferred to `recipient`, care must be\n     * taken to not create reentrancy vulnerabilities. Consider using\n     * {ReentrancyGuard} or the\n     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].\n     */\n    function sendValue(address payable recipient, uint256 amount) internal {\n        require(address(this).balance >= amount, \"Address: insufficient balance\");\n\n        (bool success, ) = recipient.call{value: amount}(\"\");\n        require(success, \"Address: unable to send value, recipient may have reverted\");\n    }\n\n    /**\n     * @dev Performs a Solidity function call using a low level `call`. A\n     * plain `call` is an unsafe replacement for a function call: use this\n     * function instead.\n     *\n     * If `target` reverts with a revert reason, it is bubbled up by this\n     * function (like regular Solidity function calls).\n     *\n     * Returns the raw returned data. To convert to the expected return value,\n     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n     *\n     * Requirements:\n     *\n     * - `target` must be a contract.\n     * - calling `target` with `data` must not revert.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, 0, \"Address: low-level call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n     * `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(\n        address target,\n        bytes memory data,\n        string memory errorMessage\n    ) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, 0, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but also transferring `value` wei to `target`.\n     *\n     * Requirements:\n     *\n     * - the calling contract must have an ETH balance of at least `value`.\n     * - the called Solidity function must be `payable`.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(\n        address target,\n        bytes memory data,\n        uint256 value\n    ) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n     * with `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(\n        address target,\n        bytes memory data,\n        uint256 value,\n        string memory errorMessage\n    ) internal returns (bytes memory) {\n        require(address(this).balance >= value, \"Address: insufficient balance for call\");\n        (bool success, bytes memory returndata) = target.call{value: value}(data);\n        return verifyCallResultFromTarget(target, success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n        return functionStaticCall(target, data, \"Address: low-level static call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(\n        address target,\n        bytes memory data,\n        string memory errorMessage\n    ) internal view returns (bytes memory) {\n        (bool success, bytes memory returndata) = target.staticcall(data);\n        return verifyCallResultFromTarget(target, success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n        return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(\n        address target,\n        bytes memory data,\n        string memory errorMessage\n    ) internal returns (bytes memory) {\n        (bool success, bytes memory returndata) = target.delegatecall(data);\n        return verifyCallResultFromTarget(target, success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling\n     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.\n     *\n     * _Available since v4.8._\n     */\n    function verifyCallResultFromTarget(\n        address target,\n        bool success,\n        bytes memory returndata,\n        string memory errorMessage\n    ) internal view returns (bytes memory) {\n        if (success) {\n            if (returndata.length == 0) {\n                // only check isContract if the call was successful and the return data is empty\n                // otherwise we already know that it was a contract\n                require(isContract(target), \"Address: call to non-contract\");\n            }\n            return returndata;\n        } else {\n            _revert(returndata, errorMessage);\n        }\n    }\n\n    /**\n     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the\n     * revert reason or using the provided one.\n     *\n     * _Available since v4.3._\n     */\n    function verifyCallResult(\n        bool success,\n        bytes memory returndata,\n        string memory errorMessage\n    ) internal pure returns (bytes memory) {\n        if (success) {\n            return returndata;\n        } else {\n            _revert(returndata, errorMessage);\n        }\n    }\n\n    function _revert(bytes memory returndata, string memory errorMessage) private pure {\n        // Look for revert reason and bubble it up if present\n        if (returndata.length > 0) {\n            // The easiest way to bubble the revert reason is using memory via assembly\n            /// @solidity memory-safe-assembly\n            assembly {\n                let returndata_size := mload(returndata)\n                revert(add(32, returndata), returndata_size)\n            }\n        } else {\n            revert(errorMessage);\n        }\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/Context.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n    function _msgSender() internal view virtual returns (address) {\n        return msg.sender;\n    }\n\n    function _msgData() internal view virtual returns (bytes calldata) {\n        return msg.data;\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/Counters.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @title Counters\n * @author Matt Condon (@shrugs)\n * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number\n * of elements in a mapping, issuing ERC721 ids, or counting request ids.\n *\n * Include with `using Counters for Counters.Counter;`\n */\nlibrary Counters {\n    struct Counter {\n        // This variable should never be directly accessed by users of the library: interactions must be restricted to\n        // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add\n        // this feature: see https://github.com/ethereum/solidity/issues/4637\n        uint256 _value; // default: 0\n    }\n\n    function current(Counter storage counter) internal view returns (uint256) {\n        return counter._value;\n    }\n\n    function increment(Counter storage counter) internal {\n        unchecked {\n            counter._value += 1;\n        }\n    }\n\n    function decrement(Counter storage counter) internal {\n        uint256 value = counter._value;\n        require(value > 0, \"Counter: decrement overflow\");\n        unchecked {\n            counter._value = value - 1;\n        }\n    }\n\n    function reset(Counter storage counter) internal {\n        counter._value = 0;\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/cryptography/MerkleProof.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (utils/cryptography/MerkleProof.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev These functions deal with verification of Merkle Tree proofs.\n *\n * The tree and the proofs can be generated using our\n * https://github.com/OpenZeppelin/merkle-tree[JavaScript library].\n * You will find a quickstart guide in the readme.\n *\n * WARNING: You should avoid using leaf values that are 64 bytes long prior to\n * hashing, or use a hash function other than keccak256 for hashing leaves.\n * This is because the concatenation of a sorted pair of internal nodes in\n * the merkle tree could be reinterpreted as a leaf value.\n * OpenZeppelin's JavaScript library generates merkle trees that are safe\n * against this attack out of the box.\n */\nlibrary MerkleProof {\n    /**\n     * @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree\n     * defined by `root`. For this, a `proof` must be provided, containing\n     * sibling hashes on the branch from the leaf to the root of the tree. Each\n     * pair of leaves and each pair of pre-images are assumed to be sorted.\n     */\n    function verify(\n        bytes32[] memory proof,\n        bytes32 root,\n        bytes32 leaf\n    ) internal pure returns (bool) {\n        return processProof(proof, leaf) == root;\n    }\n\n    /**\n     * @dev Calldata version of {verify}\n     *\n     * _Available since v4.7._\n     */\n    function verifyCalldata(\n        bytes32[] calldata proof,\n        bytes32 root,\n        bytes32 leaf\n    ) internal pure returns (bool) {\n        return processProofCalldata(proof, leaf) == root;\n    }\n\n    /**\n     * @dev Returns the rebuilt hash obtained by traversing a Merkle tree up\n     * from `leaf` using `proof`. A `proof` is valid if and only if the rebuilt\n     * hash matches the root of the tree. When processing the proof, the pairs\n     * of leafs & pre-images are assumed to be sorted.\n     *\n     * _Available since v4.4._\n     */\n    function processProof(bytes32[] memory proof, bytes32 leaf) internal pure returns (bytes32) {\n        bytes32 computedHash = leaf;\n        for (uint256 i = 0; i < proof.length; i++) {\n            computedHash = _hashPair(computedHash, proof[i]);\n        }\n        return computedHash;\n    }\n\n    /**\n     * @dev Calldata version of {processProof}\n     *\n     * _Available since v4.7._\n     */\n    function processProofCalldata(bytes32[] calldata proof, bytes32 leaf) internal pure returns (bytes32) {\n        bytes32 computedHash = leaf;\n        for (uint256 i = 0; i < proof.length; i++) {\n            computedHash = _hashPair(computedHash, proof[i]);\n        }\n        return computedHash;\n    }\n\n    /**\n     * @dev Returns true if the `leaves` can be simultaneously proven to be a part of a merkle tree defined by\n     * `root`, according to `proof` and `proofFlags` as described in {processMultiProof}.\n     *\n     * CAUTION: Not all merkle trees admit multiproofs. See {processMultiProof} for details.\n     *\n     * _Available since v4.7._\n     */\n    function multiProofVerify(\n        bytes32[] memory proof,\n        bool[] memory proofFlags,\n        bytes32 root,\n        bytes32[] memory leaves\n    ) internal pure returns (bool) {\n        return processMultiProof(proof, proofFlags, leaves) == root;\n    }\n\n    /**\n     * @dev Calldata version of {multiProofVerify}\n     *\n     * CAUTION: Not all merkle trees admit multiproofs. See {processMultiProof} for details.\n     *\n     * _Available since v4.7._\n     */\n    function multiProofVerifyCalldata(\n        bytes32[] calldata proof,\n        bool[] calldata proofFlags,\n        bytes32 root,\n        bytes32[] memory leaves\n    ) internal pure returns (bool) {\n        return processMultiProofCalldata(proof, proofFlags, leaves) == root;\n    }\n\n    /**\n     * @dev Returns the root of a tree reconstructed from `leaves` and sibling nodes in `proof`. The reconstruction\n     * proceeds by incrementally reconstructing all inner nodes by combining a leaf/inner node with either another\n     * leaf/inner node or a proof sibling node, depending on whether each `proofFlags` item is true or false\n     * respectively.\n     *\n     * CAUTION: Not all merkle trees admit multiproofs. To use multiproofs, it is sufficient to ensure that: 1) the tree\n     * is complete (but not necessarily perfect), 2) the leaves to be proven are in the opposite order they are in the\n     * tree (i.e., as seen from right to left starting at the deepest layer and continuing at the next layer).\n     *\n     * _Available since v4.7._\n     */\n    function processMultiProof(\n        bytes32[] memory proof,\n        bool[] memory proofFlags,\n        bytes32[] memory leaves\n    ) internal pure returns (bytes32 merkleRoot) {\n        // This function rebuild the root hash by traversing the tree up from the leaves. The root is rebuilt by\n        // consuming and producing values on a queue. The queue starts with the `leaves` array, then goes onto the\n        // `hashes` array. At the end of the process, the last hash in the `hashes` array should contain the root of\n        // the merkle tree.\n        uint256 leavesLen = leaves.length;\n        uint256 totalHashes = proofFlags.length;\n\n        // Check proof validity.\n        require(leavesLen + proof.length - 1 == totalHashes, \"MerkleProof: invalid multiproof\");\n\n        // The xxxPos values are \"pointers\" to the next value to consume in each array. All accesses are done using\n        // `xxx[xxxPos++]`, which return the current value and increment the pointer, thus mimicking a queue's \"pop\".\n        bytes32[] memory hashes = new bytes32[](totalHashes);\n        uint256 leafPos = 0;\n        uint256 hashPos = 0;\n        uint256 proofPos = 0;\n        // At each step, we compute the next hash using two values:\n        // - a value from the \"main queue\". If not all leaves have been consumed, we get the next leaf, otherwise we\n        //   get the next hash.\n        // - depending on the flag, either another value for the \"main queue\" (merging branches) or an element from the\n        //   `proof` array.\n        for (uint256 i = 0; i < totalHashes; i++) {\n            bytes32 a = leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++];\n            bytes32 b = proofFlags[i] ? leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++] : proof[proofPos++];\n            hashes[i] = _hashPair(a, b);\n        }\n\n        if (totalHashes > 0) {\n            return hashes[totalHashes - 1];\n        } else if (leavesLen > 0) {\n            return leaves[0];\n        } else {\n            return proof[0];\n        }\n    }\n\n    /**\n     * @dev Calldata version of {processMultiProof}.\n     *\n     * CAUTION: Not all merkle trees admit multiproofs. See {processMultiProof} for details.\n     *\n     * _Available since v4.7._\n     */\n    function processMultiProofCalldata(\n        bytes32[] calldata proof,\n        bool[] calldata proofFlags,\n        bytes32[] memory leaves\n    ) internal pure returns (bytes32 merkleRoot) {\n        // This function rebuild the root hash by traversing the tree up from the leaves. The root is rebuilt by\n        // consuming and producing values on a queue. The queue starts with the `leaves` array, then goes onto the\n        // `hashes` array. At the end of the process, the last hash in the `hashes` array should contain the root of\n        // the merkle tree.\n        uint256 leavesLen = leaves.length;\n        uint256 totalHashes = proofFlags.length;\n\n        // Check proof validity.\n        require(leavesLen + proof.length - 1 == totalHashes, \"MerkleProof: invalid multiproof\");\n\n        // The xxxPos values are \"pointers\" to the next value to consume in each array. All accesses are done using\n        // `xxx[xxxPos++]`, which return the current value and increment the pointer, thus mimicking a queue's \"pop\".\n        bytes32[] memory hashes = new bytes32[](totalHashes);\n        uint256 leafPos = 0;\n        uint256 hashPos = 0;\n        uint256 proofPos = 0;\n        // At each step, we compute the next hash using two values:\n        // - a value from the \"main queue\". If not all leaves have been consumed, we get the next leaf, otherwise we\n        //   get the next hash.\n        // - depending on the flag, either another value for the \"main queue\" (merging branches) or an element from the\n        //   `proof` array.\n        for (uint256 i = 0; i < totalHashes; i++) {\n            bytes32 a = leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++];\n            bytes32 b = proofFlags[i] ? leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++] : proof[proofPos++];\n            hashes[i] = _hashPair(a, b);\n        }\n\n        if (totalHashes > 0) {\n            return hashes[totalHashes - 1];\n        } else if (leavesLen > 0) {\n            return leaves[0];\n        } else {\n            return proof[0];\n        }\n    }\n\n    function _hashPair(bytes32 a, bytes32 b) private pure returns (bytes32) {\n        return a < b ? _efficientHash(a, b) : _efficientHash(b, a);\n    }\n\n    function _efficientHash(bytes32 a, bytes32 b) private pure returns (bytes32 value) {\n        /// @solidity memory-safe-assembly\n        assembly {\n            mstore(0x00, a)\n            mstore(0x20, b)\n            value := keccak256(0x00, 0x40)\n        }\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/introspection/ERC165.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IERC165.sol\";\n\n/**\n * @dev Implementation of the {IERC165} interface.\n *\n * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check\n * for the additional interface id that will be supported. For example:\n *\n * ```solidity\n * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);\n * }\n * ```\n *\n * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.\n */\nabstract contract ERC165 is IERC165 {\n    /**\n     * @dev See {IERC165-supportsInterface}.\n     */\n    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n        return interfaceId == type(IERC165).interfaceId;\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/introspection/IERC165.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC165 standard, as defined in the\n * https://eips.ethereum.org/EIPS/eip-165[EIP].\n *\n * Implementers can declare support of contract interfaces, which can then be\n * queried by others ({ERC165Checker}).\n *\n * For an implementation, see {ERC165}.\n */\ninterface IERC165 {\n    /**\n     * @dev Returns true if this contract implements the interface defined by\n     * `interfaceId`. See the corresponding\n     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]\n     * to learn more about how these ids are created.\n     *\n     * This function call must use less than 30 000 gas.\n     */\n    function supportsInterface(bytes4 interfaceId) external view returns (bool);\n}\n"
    },
    "@openzeppelin/contracts/utils/math/Math.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/Math.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Standard math utilities missing in the Solidity language.\n */\nlibrary Math {\n    enum Rounding {\n        Down, // Toward negative infinity\n        Up, // Toward infinity\n        Zero // Toward zero\n    }\n\n    /**\n     * @dev Returns the largest of two numbers.\n     */\n    function max(uint256 a, uint256 b) internal pure returns (uint256) {\n        return a > b ? a : b;\n    }\n\n    /**\n     * @dev Returns the smallest of two numbers.\n     */\n    function min(uint256 a, uint256 b) internal pure returns (uint256) {\n        return a < b ? a : b;\n    }\n\n    /**\n     * @dev Returns the average of two numbers. The result is rounded towards\n     * zero.\n     */\n    function average(uint256 a, uint256 b) internal pure returns (uint256) {\n        // (a + b) / 2 can overflow.\n        return (a & b) + (a ^ b) / 2;\n    }\n\n    /**\n     * @dev Returns the ceiling of the division of two numbers.\n     *\n     * This differs from standard division with `/` in that it rounds up instead\n     * of rounding down.\n     */\n    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {\n        // (a + b - 1) / b can overflow on addition, so we distribute.\n        return a == 0 ? 0 : (a - 1) / b + 1;\n    }\n\n    /**\n     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0\n     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)\n     * with further edits by Uniswap Labs also under MIT license.\n     */\n    function mulDiv(\n        uint256 x,\n        uint256 y,\n        uint256 denominator\n    ) internal pure returns (uint256 result) {\n        unchecked {\n            // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use\n            // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256\n            // variables such that product = prod1 * 2^256 + prod0.\n            uint256 prod0; // Least significant 256 bits of the product\n            uint256 prod1; // Most significant 256 bits of the product\n            assembly {\n                let mm := mulmod(x, y, not(0))\n                prod0 := mul(x, y)\n                prod1 := sub(sub(mm, prod0), lt(mm, prod0))\n            }\n\n            // Handle non-overflow cases, 256 by 256 division.\n            if (prod1 == 0) {\n                return prod0 / denominator;\n            }\n\n            // Make sure the result is less than 2^256. Also prevents denominator == 0.\n            require(denominator > prod1);\n\n            ///////////////////////////////////////////////\n            // 512 by 256 division.\n            ///////////////////////////////////////////////\n\n            // Make division exact by subtracting the remainder from [prod1 prod0].\n            uint256 remainder;\n            assembly {\n                // Compute remainder using mulmod.\n                remainder := mulmod(x, y, denominator)\n\n                // Subtract 256 bit number from 512 bit number.\n                prod1 := sub(prod1, gt(remainder, prod0))\n                prod0 := sub(prod0, remainder)\n            }\n\n            // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.\n            // See https://cs.stackexchange.com/q/138556/92363.\n\n            // Does not overflow because the denominator cannot be zero at this stage in the function.\n            uint256 twos = denominator & (~denominator + 1);\n            assembly {\n                // Divide denominator by twos.\n                denominator := div(denominator, twos)\n\n                // Divide [prod1 prod0] by twos.\n                prod0 := div(prod0, twos)\n\n                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.\n                twos := add(div(sub(0, twos), twos), 1)\n            }\n\n            // Shift in bits from prod1 into prod0.\n            prod0 |= prod1 * twos;\n\n            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such\n            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for\n            // four bits. That is, denominator * inv = 1 mod 2^4.\n            uint256 inverse = (3 * denominator) ^ 2;\n\n            // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works\n            // in modular arithmetic, doubling the correct bits in each step.\n            inverse *= 2 - denominator * inverse; // inverse mod 2^8\n            inverse *= 2 - denominator * inverse; // inverse mod 2^16\n            inverse *= 2 - denominator * inverse; // inverse mod 2^32\n            inverse *= 2 - denominator * inverse; // inverse mod 2^64\n            inverse *= 2 - denominator * inverse; // inverse mod 2^128\n            inverse *= 2 - denominator * inverse; // inverse mod 2^256\n\n            // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.\n            // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is\n            // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1\n            // is no longer required.\n            result = prod0 * inverse;\n            return result;\n        }\n    }\n\n    /**\n     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.\n     */\n    function mulDiv(\n        uint256 x,\n        uint256 y,\n        uint256 denominator,\n        Rounding rounding\n    ) internal pure returns (uint256) {\n        uint256 result = mulDiv(x, y, denominator);\n        if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {\n            result += 1;\n        }\n        return result;\n    }\n\n    /**\n     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.\n     *\n     * Inspired by Henry S. Warren, Jr.'s \"Hacker's Delight\" (Chapter 11).\n     */\n    function sqrt(uint256 a) internal pure returns (uint256) {\n        if (a == 0) {\n            return 0;\n        }\n\n        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.\n        //\n        // We know that the \"msb\" (most significant bit) of our target number `a` is a power of 2 such that we have\n        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.\n        //\n        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`\n        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`\n        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`\n        //\n        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.\n        uint256 result = 1 << (log2(a) >> 1);\n\n        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,\n        // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at\n        // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision\n        // into the expected uint128 result.\n        unchecked {\n            result = (result + a / result) >> 1;\n            result = (result + a / result) >> 1;\n            result = (result + a / result) >> 1;\n            result = (result + a / result) >> 1;\n            result = (result + a / result) >> 1;\n            result = (result + a / result) >> 1;\n            result = (result + a / result) >> 1;\n            return min(result, a / result);\n        }\n    }\n\n    /**\n     * @notice Calculates sqrt(a), following the selected rounding direction.\n     */\n    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {\n        unchecked {\n            uint256 result = sqrt(a);\n            return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);\n        }\n    }\n\n    /**\n     * @dev Return the log in base 2, rounded down, of a positive value.\n     * Returns 0 if given 0.\n     */\n    function log2(uint256 value) internal pure returns (uint256) {\n        uint256 result = 0;\n        unchecked {\n            if (value >> 128 > 0) {\n                value >>= 128;\n                result += 128;\n            }\n            if (value >> 64 > 0) {\n                value >>= 64;\n                result += 64;\n            }\n            if (value >> 32 > 0) {\n                value >>= 32;\n                result += 32;\n            }\n            if (value >> 16 > 0) {\n                value >>= 16;\n                result += 16;\n            }\n            if (value >> 8 > 0) {\n                value >>= 8;\n                result += 8;\n            }\n            if (value >> 4 > 0) {\n                value >>= 4;\n                result += 4;\n            }\n            if (value >> 2 > 0) {\n                value >>= 2;\n                result += 2;\n            }\n            if (value >> 1 > 0) {\n                result += 1;\n            }\n        }\n        return result;\n    }\n\n    /**\n     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.\n     * Returns 0 if given 0.\n     */\n    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {\n        unchecked {\n            uint256 result = log2(value);\n            return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);\n        }\n    }\n\n    /**\n     * @dev Return the log in base 10, rounded down, of a positive value.\n     * Returns 0 if given 0.\n     */\n    function log10(uint256 value) internal pure returns (uint256) {\n        uint256 result = 0;\n        unchecked {\n            if (value >= 10**64) {\n                value /= 10**64;\n                result += 64;\n            }\n            if (value >= 10**32) {\n                value /= 10**32;\n                result += 32;\n            }\n            if (value >= 10**16) {\n                value /= 10**16;\n                result += 16;\n            }\n            if (value >= 10**8) {\n                value /= 10**8;\n                result += 8;\n            }\n            if (value >= 10**4) {\n                value /= 10**4;\n                result += 4;\n            }\n            if (value >= 10**2) {\n                value /= 10**2;\n                result += 2;\n            }\n            if (value >= 10**1) {\n                result += 1;\n            }\n        }\n        return result;\n    }\n\n    /**\n     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.\n     * Returns 0 if given 0.\n     */\n    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {\n        unchecked {\n            uint256 result = log10(value);\n            return result + (rounding == Rounding.Up && 10**result < value ? 1 : 0);\n        }\n    }\n\n    /**\n     * @dev Return the log in base 256, rounded down, of a positive value.\n     * Returns 0 if given 0.\n     *\n     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.\n     */\n    function log256(uint256 value) internal pure returns (uint256) {\n        uint256 result = 0;\n        unchecked {\n            if (value >> 128 > 0) {\n                value >>= 128;\n                result += 16;\n            }\n            if (value >> 64 > 0) {\n                value >>= 64;\n                result += 8;\n            }\n            if (value >> 32 > 0) {\n                value >>= 32;\n                result += 4;\n            }\n            if (value >> 16 > 0) {\n                value >>= 16;\n                result += 2;\n            }\n            if (value >> 8 > 0) {\n                result += 1;\n            }\n        }\n        return result;\n    }\n\n    /**\n     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.\n     * Returns 0 if given 0.\n     */\n    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {\n        unchecked {\n            uint256 result = log256(value);\n            return result + (rounding == Rounding.Up && 1 << (result * 8) < value ? 1 : 0);\n        }\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/Strings.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (utils/Strings.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./math/Math.sol\";\n\n/**\n * @dev String operations.\n */\nlibrary Strings {\n    bytes16 private constant _SYMBOLS = \"0123456789abcdef\";\n    uint8 private constant _ADDRESS_LENGTH = 20;\n\n    /**\n     * @dev Converts a `uint256` to its ASCII `string` decimal representation.\n     */\n    function toString(uint256 value) internal pure returns (string memory) {\n        unchecked {\n            uint256 length = Math.log10(value) + 1;\n            string memory buffer = new string(length);\n            uint256 ptr;\n            /// @solidity memory-safe-assembly\n            assembly {\n                ptr := add(buffer, add(32, length))\n            }\n            while (true) {\n                ptr--;\n                /// @solidity memory-safe-assembly\n                assembly {\n                    mstore8(ptr, byte(mod(value, 10), _SYMBOLS))\n                }\n                value /= 10;\n                if (value == 0) break;\n            }\n            return buffer;\n        }\n    }\n\n    /**\n     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.\n     */\n    function toHexString(uint256 value) internal pure returns (string memory) {\n        unchecked {\n            return toHexString(value, Math.log256(value) + 1);\n        }\n    }\n\n    /**\n     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.\n     */\n    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {\n        bytes memory buffer = new bytes(2 * length + 2);\n        buffer[0] = \"0\";\n        buffer[1] = \"x\";\n        for (uint256 i = 2 * length + 1; i > 1; --i) {\n            buffer[i] = _SYMBOLS[value & 0xf];\n            value >>= 4;\n        }\n        require(value == 0, \"Strings: hex length insufficient\");\n        return string(buffer);\n    }\n\n    /**\n     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.\n     */\n    function toHexString(address addr) internal pure returns (string memory) {\n        return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/structs/EnumerableSet.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (utils/structs/EnumerableSet.sol)\n// This file was procedurally generated from scripts/generate/templates/EnumerableSet.js.\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Library for managing\n * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive\n * types.\n *\n * Sets have the following properties:\n *\n * - Elements are added, removed, and checked for existence in constant time\n * (O(1)).\n * - Elements are enumerated in O(n). No guarantees are made on the ordering.\n *\n * ```\n * contract Example {\n *     // Add the library methods\n *     using EnumerableSet for EnumerableSet.AddressSet;\n *\n *     // Declare a set state variable\n *     EnumerableSet.AddressSet private mySet;\n * }\n * ```\n *\n * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)\n * and `uint256` (`UintSet`) are supported.\n *\n * [WARNING]\n * ====\n * Trying to delete such a structure from storage will likely result in data corruption, rendering the structure\n * unusable.\n * See https://github.com/ethereum/solidity/pull/11843[ethereum/solidity#11843] for more info.\n *\n * In order to clean an EnumerableSet, you can either remove all elements one by one or create a fresh instance using an\n * array of EnumerableSet.\n * ====\n */\nlibrary EnumerableSet {\n    // To implement this library for multiple types with as little code\n    // repetition as possible, we write it in terms of a generic Set type with\n    // bytes32 values.\n    // The Set implementation uses private functions, and user-facing\n    // implementations (such as AddressSet) are just wrappers around the\n    // underlying Set.\n    // This means that we can only create new EnumerableSets for types that fit\n    // in bytes32.\n\n    struct Set {\n        // Storage of set values\n        bytes32[] _values;\n        // Position of the value in the `values` array, plus 1 because index 0\n        // means a value is not in the set.\n        mapping(bytes32 => uint256) _indexes;\n    }\n\n    /**\n     * @dev Add a value to a set. O(1).\n     *\n     * Returns true if the value was added to the set, that is if it was not\n     * already present.\n     */\n    function _add(Set storage set, bytes32 value) private returns (bool) {\n        if (!_contains(set, value)) {\n            set._values.push(value);\n            // The value is stored at length-1, but we add 1 to all indexes\n            // and use 0 as a sentinel value\n            set._indexes[value] = set._values.length;\n            return true;\n        } else {\n            return false;\n        }\n    }\n\n    /**\n     * @dev Removes a value from a set. O(1).\n     *\n     * Returns true if the value was removed from the set, that is if it was\n     * present.\n     */\n    function _remove(Set storage set, bytes32 value) private returns (bool) {\n        // We read and store the value's index to prevent multiple reads from the same storage slot\n        uint256 valueIndex = set._indexes[value];\n\n        if (valueIndex != 0) {\n            // Equivalent to contains(set, value)\n            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in\n            // the array, and then remove the last element (sometimes called as 'swap and pop').\n            // This modifies the order of the array, as noted in {at}.\n\n            uint256 toDeleteIndex = valueIndex - 1;\n            uint256 lastIndex = set._values.length - 1;\n\n            if (lastIndex != toDeleteIndex) {\n                bytes32 lastValue = set._values[lastIndex];\n\n                // Move the last value to the index where the value to delete is\n                set._values[toDeleteIndex] = lastValue;\n                // Update the index for the moved value\n                set._indexes[lastValue] = valueIndex; // Replace lastValue's index to valueIndex\n            }\n\n            // Delete the slot where the moved value was stored\n            set._values.pop();\n\n            // Delete the index for the deleted slot\n            delete set._indexes[value];\n\n            return true;\n        } else {\n            return false;\n        }\n    }\n\n    /**\n     * @dev Returns true if the value is in the set. O(1).\n     */\n    function _contains(Set storage set, bytes32 value) private view returns (bool) {\n        return set._indexes[value] != 0;\n    }\n\n    /**\n     * @dev Returns the number of values on the set. O(1).\n     */\n    function _length(Set storage set) private view returns (uint256) {\n        return set._values.length;\n    }\n\n    /**\n     * @dev Returns the value stored at position `index` in the set. O(1).\n     *\n     * Note that there are no guarantees on the ordering of values inside the\n     * array, and it may change when more values are added or removed.\n     *\n     * Requirements:\n     *\n     * - `index` must be strictly less than {length}.\n     */\n    function _at(Set storage set, uint256 index) private view returns (bytes32) {\n        return set._values[index];\n    }\n\n    /**\n     * @dev Return the entire set in an array\n     *\n     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed\n     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that\n     * this function has an unbounded cost, and using it as part of a state-changing function may render the function\n     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.\n     */\n    function _values(Set storage set) private view returns (bytes32[] memory) {\n        return set._values;\n    }\n\n    // Bytes32Set\n\n    struct Bytes32Set {\n        Set _inner;\n    }\n\n    /**\n     * @dev Add a value to a set. O(1).\n     *\n     * Returns true if the value was added to the set, that is if it was not\n     * already present.\n     */\n    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {\n        return _add(set._inner, value);\n    }\n\n    /**\n     * @dev Removes a value from a set. O(1).\n     *\n     * Returns true if the value was removed from the set, that is if it was\n     * present.\n     */\n    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {\n        return _remove(set._inner, value);\n    }\n\n    /**\n     * @dev Returns true if the value is in the set. O(1).\n     */\n    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {\n        return _contains(set._inner, value);\n    }\n\n    /**\n     * @dev Returns the number of values in the set. O(1).\n     */\n    function length(Bytes32Set storage set) internal view returns (uint256) {\n        return _length(set._inner);\n    }\n\n    /**\n     * @dev Returns the value stored at position `index` in the set. O(1).\n     *\n     * Note that there are no guarantees on the ordering of values inside the\n     * array, and it may change when more values are added or removed.\n     *\n     * Requirements:\n     *\n     * - `index` must be strictly less than {length}.\n     */\n    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {\n        return _at(set._inner, index);\n    }\n\n    /**\n     * @dev Return the entire set in an array\n     *\n     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed\n     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that\n     * this function has an unbounded cost, and using it as part of a state-changing function may render the function\n     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.\n     */\n    function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {\n        bytes32[] memory store = _values(set._inner);\n        bytes32[] memory result;\n\n        /// @solidity memory-safe-assembly\n        assembly {\n            result := store\n        }\n\n        return result;\n    }\n\n    // AddressSet\n\n    struct AddressSet {\n        Set _inner;\n    }\n\n    /**\n     * @dev Add a value to a set. O(1).\n     *\n     * Returns true if the value was added to the set, that is if it was not\n     * already present.\n     */\n    function add(AddressSet storage set, address value) internal returns (bool) {\n        return _add(set._inner, bytes32(uint256(uint160(value))));\n    }\n\n    /**\n     * @dev Removes a value from a set. O(1).\n     *\n     * Returns true if the value was removed from the set, that is if it was\n     * present.\n     */\n    function remove(AddressSet storage set, address value) internal returns (bool) {\n        return _remove(set._inner, bytes32(uint256(uint160(value))));\n    }\n\n    /**\n     * @dev Returns true if the value is in the set. O(1).\n     */\n    function contains(AddressSet storage set, address value) internal view returns (bool) {\n        return _contains(set._inner, bytes32(uint256(uint160(value))));\n    }\n\n    /**\n     * @dev Returns the number of values in the set. O(1).\n     */\n    function length(AddressSet storage set) internal view returns (uint256) {\n        return _length(set._inner);\n    }\n\n    /**\n     * @dev Returns the value stored at position `index` in the set. O(1).\n     *\n     * Note that there are no guarantees on the ordering of values inside the\n     * array, and it may change when more values are added or removed.\n     *\n     * Requirements:\n     *\n     * - `index` must be strictly less than {length}.\n     */\n    function at(AddressSet storage set, uint256 index) internal view returns (address) {\n        return address(uint160(uint256(_at(set._inner, index))));\n    }\n\n    /**\n     * @dev Return the entire set in an array\n     *\n     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed\n     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that\n     * this function has an unbounded cost, and using it as part of a state-changing function may render the function\n     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.\n     */\n    function values(AddressSet storage set) internal view returns (address[] memory) {\n        bytes32[] memory store = _values(set._inner);\n        address[] memory result;\n\n        /// @solidity memory-safe-assembly\n        assembly {\n            result := store\n        }\n\n        return result;\n    }\n\n    // UintSet\n\n    struct UintSet {\n        Set _inner;\n    }\n\n    /**\n     * @dev Add a value to a set. O(1).\n     *\n     * Returns true if the value was added to the set, that is if it was not\n     * already present.\n     */\n    function add(UintSet storage set, uint256 value) internal returns (bool) {\n        return _add(set._inner, bytes32(value));\n    }\n\n    /**\n     * @dev Removes a value from a set. O(1).\n     *\n     * Returns true if the value was removed from the set, that is if it was\n     * present.\n     */\n    function remove(UintSet storage set, uint256 value) internal returns (bool) {\n        return _remove(set._inner, bytes32(value));\n    }\n\n    /**\n     * @dev Returns true if the value is in the set. O(1).\n     */\n    function contains(UintSet storage set, uint256 value) internal view returns (bool) {\n        return _contains(set._inner, bytes32(value));\n    }\n\n    /**\n     * @dev Returns the number of values in the set. O(1).\n     */\n    function length(UintSet storage set) internal view returns (uint256) {\n        return _length(set._inner);\n    }\n\n    /**\n     * @dev Returns the value stored at position `index` in the set. O(1).\n     *\n     * Note that there are no guarantees on the ordering of values inside the\n     * array, and it may change when more values are added or removed.\n     *\n     * Requirements:\n     *\n     * - `index` must be strictly less than {length}.\n     */\n    function at(UintSet storage set, uint256 index) internal view returns (uint256) {\n        return uint256(_at(set._inner, index));\n    }\n\n    /**\n     * @dev Return the entire set in an array\n     *\n     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed\n     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that\n     * this function has an unbounded cost, and using it as part of a state-changing function may render the function\n     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.\n     */\n    function values(UintSet storage set) internal view returns (uint256[] memory) {\n        bytes32[] memory store = _values(set._inner);\n        uint256[] memory result;\n\n        /// @solidity memory-safe-assembly\n        assembly {\n            result := store\n        }\n\n        return result;\n    }\n}\n"
    },
    "base64-sol/base64.sol": {
      "content": "// SPDX-License-Identifier: MIT\n\npragma solidity >=0.6.0;\n\n/// @title Base64\n/// @author Brecht Devos - <brecht@loopring.org>\n/// @notice Provides functions for encoding/decoding base64\nlibrary Base64 {\n    string internal constant TABLE_ENCODE = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';\n    bytes  internal constant TABLE_DECODE = hex\"0000000000000000000000000000000000000000000000000000000000000000\"\n                                            hex\"00000000000000000000003e0000003f3435363738393a3b3c3d000000000000\"\n                                            hex\"00000102030405060708090a0b0c0d0e0f101112131415161718190000000000\"\n                                            hex\"001a1b1c1d1e1f202122232425262728292a2b2c2d2e2f303132330000000000\";\n\n    function encode(bytes memory data) internal pure returns (string memory) {\n        if (data.length == 0) return '';\n\n        // load the table into memory\n        string memory table = TABLE_ENCODE;\n\n        // multiply by 4/3 rounded up\n        uint256 encodedLen = 4 * ((data.length + 2) / 3);\n\n        // add some extra buffer at the end required for the writing\n        string memory result = new string(encodedLen + 32);\n\n        assembly {\n            // set the actual output length\n            mstore(result, encodedLen)\n\n            // prepare the lookup table\n            let tablePtr := add(table, 1)\n\n            // input ptr\n            let dataPtr := data\n            let endPtr := add(dataPtr, mload(data))\n\n            // result ptr, jump over length\n            let resultPtr := add(result, 32)\n\n            // run over the input, 3 bytes at a time\n            for {} lt(dataPtr, endPtr) {}\n            {\n                // read 3 bytes\n                dataPtr := add(dataPtr, 3)\n                let input := mload(dataPtr)\n\n                // write 4 characters\n                mstore8(resultPtr, mload(add(tablePtr, and(shr(18, input), 0x3F))))\n                resultPtr := add(resultPtr, 1)\n                mstore8(resultPtr, mload(add(tablePtr, and(shr(12, input), 0x3F))))\n                resultPtr := add(resultPtr, 1)\n                mstore8(resultPtr, mload(add(tablePtr, and(shr( 6, input), 0x3F))))\n                resultPtr := add(resultPtr, 1)\n                mstore8(resultPtr, mload(add(tablePtr, and(        input,  0x3F))))\n                resultPtr := add(resultPtr, 1)\n            }\n\n            // padding with '='\n            switch mod(mload(data), 3)\n            case 1 { mstore(sub(resultPtr, 2), shl(240, 0x3d3d)) }\n            case 2 { mstore(sub(resultPtr, 1), shl(248, 0x3d)) }\n        }\n\n        return result;\n    }\n\n    function decode(string memory _data) internal pure returns (bytes memory) {\n        bytes memory data = bytes(_data);\n\n        if (data.length == 0) return new bytes(0);\n        require(data.length % 4 == 0, \"invalid base64 decoder input\");\n\n        // load the table into memory\n        bytes memory table = TABLE_DECODE;\n\n        // every 4 characters represent 3 bytes\n        uint256 decodedLen = (data.length / 4) * 3;\n\n        // add some extra buffer at the end required for the writing\n        bytes memory result = new bytes(decodedLen + 32);\n\n        assembly {\n            // padding with '='\n            let lastBytes := mload(add(data, mload(data)))\n            if eq(and(lastBytes, 0xFF), 0x3d) {\n                decodedLen := sub(decodedLen, 1)\n                if eq(and(lastBytes, 0xFFFF), 0x3d3d) {\n                    decodedLen := sub(decodedLen, 1)\n                }\n            }\n\n            // set the actual output length\n            mstore(result, decodedLen)\n\n            // prepare the lookup table\n            let tablePtr := add(table, 1)\n\n            // input ptr\n            let dataPtr := data\n            let endPtr := add(dataPtr, mload(data))\n\n            // result ptr, jump over length\n            let resultPtr := add(result, 32)\n\n            // run over the input, 4 characters at a time\n            for {} lt(dataPtr, endPtr) {}\n            {\n               // read 4 characters\n               dataPtr := add(dataPtr, 4)\n               let input := mload(dataPtr)\n\n               // write 3 bytes\n               let output := add(\n                   add(\n                       shl(18, and(mload(add(tablePtr, and(shr(24, input), 0xFF))), 0xFF)),\n                       shl(12, and(mload(add(tablePtr, and(shr(16, input), 0xFF))), 0xFF))),\n                   add(\n                       shl( 6, and(mload(add(tablePtr, and(shr( 8, input), 0xFF))), 0xFF)),\n                               and(mload(add(tablePtr, and(        input , 0xFF))), 0xFF)\n                    )\n                )\n                mstore(resultPtr, shl(232, output))\n                resultPtr := add(resultPtr, 3)\n            }\n        }\n\n        return result;\n    }\n}\n"
    },
    "contracts/interfaces/IForcedOffline.sol": {
      "content": "// SPDX-License-Identifier: MIT\npragma solidity ^0.8.17;\n\ninterface IForcedOffline {\n    function reveal(uint tokenId_) external;\n}"
    },
    "contracts/interfaces/IRandomConsumer.sol": {
      "content": "// SPDX-License-Identifier: MIT\npragma solidity ^0.8.17;\n\ninterface IRandomConsumer {\n    function runFulfillRandomness(uint256 tokenId_, address user_, uint256 randomness_) external;\n}"
    },
    "contracts/interfaces/IRandomGenerator.sol": {
      "content": "// SPDX-License-Identifier: MIT\npragma solidity ^0.8.17;\n\ninterface IRandomGenerator {\n    function requestRandomNumber(uint256 tokenId, address user) external;\n    function requestRandomNumber(uint256 tokenId, address user, uint32 callbackGasLimit_) external;\n}"
    },
    "contracts/MysteryBox.sol": {
      "content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.17;\n\n/*\n███████╗ ██████╗ ██████╗  ██████╗███████╗██████╗      ██████╗ ███████╗███████╗██╗     ██╗███╗   ██╗███████╗\n██╔════╝██╔═══██╗██╔══██╗██╔════╝██╔════╝██╔══██╗    ██╔═══██╗██╔════╝██╔════╝██║     ██║████╗  ██║██╔════╝\n█████╗  ██║   ██║██████╔╝██║     █████╗  ██║  ██║    ██║   ██║█████╗  █████╗  ██║     ██║██╔██╗ ██║█████╗\n██╔══╝  ██║   ██║██╔══██╗██║     ██╔══╝  ██║  ██║    ██║   ██║██╔══╝  ██╔══╝  ██║     ██║██║╚██╗██║██╔══╝\n██║     ╚██████╔╝██║  ██║╚██████╗███████╗██████╔╝    ╚██████╔╝██║     ██║     ███████╗██║██║ ╚████║███████╗\n╚═╝      ╚═════╝ ╚═╝  ╚═╝ ╚═════╝╚══════╝╚═════╝      ╚═════╝ ╚═╝     ╚═╝     ╚══════╝╚═╝╚═╝  ╚═══╝╚══════╝\n*/\n\nimport \"@openzeppelin/contracts/utils/Counters.sol\";\nimport \"@openzeppelin/contracts/token/ERC721/utils/ERC721Holder.sol\";\nimport \"@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol\";\nimport \"@openzeppelin/contracts/token/ERC20/IERC20.sol\";\nimport \"@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol\";\nimport \"@openzeppelin/contracts/utils/structs/EnumerableSet.sol\";\nimport \"@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol\";\nimport \"@openzeppelin/contracts/token/ERC721/extensions/ERC721Burnable.sol\";\nimport \"@openzeppelin/contracts/token/ERC721/extensions/ERC721Pausable.sol\";\nimport \"@openzeppelin/contracts/access/AccessControlEnumerable.sol\";\nimport \"@openzeppelin/contracts/utils/Context.sol\";\nimport \"@openzeppelin/contracts/utils/cryptography/MerkleProof.sol\";\nimport { Base64 } from 'base64-sol/base64.sol';\nimport \"./interfaces/IRandomConsumer.sol\";\nimport \"./interfaces/IRandomGenerator.sol\";\nimport \"./interfaces/IForcedOffline.sol\";\n\ncontract MysteryBox is\nContext,\nAccessControlEnumerable,\nERC721Enumerable,\nERC721Burnable,\nERC721Pausable,\nERC721Holder,\nIRandomConsumer\n{\n    using Counters for Counters.Counter;\n    using Address for address;\n    using Strings for uint256;\n    using SafeERC20 for IERC20;\n    using EnumerableSet for EnumerableSet.UintSet;\n    using EnumerableSet for EnumerableSet.AddressSet;\n\n    /*//////////////////////////////////////////////////////////////\n                               CONSTANTS\n    //////////////////////////////////////////////////////////////*/\n    bytes32 public constant PAUSER_ROLE = keccak256(\"PAUSER_ROLE\");\n    bytes32 public constant ADMIN_ROLE = keccak256(\"ADMIN_ROLE\");\n\n    /*//////////////////////////////////////////////////////////////\n                               ADDRESSES\n    //////////////////////////////////////////////////////////////*/\n    IForcedOffline public nftToken;\n\n    IRandomGenerator public randomGenerator;\n\n    /*//////////////////////////////////////////////////////////////\n                              MINTING STATE\n    //////////////////////////////////////////////////////////////*/\n    Counters.Counter private _tokenIdTracker;\n\n    bytes32 public merkleRoot;\n\n    uint public totalMysteryBoxQuota;\n    uint public totalMysteryBoxSold;\n\n    mapping (address => uint) public whitelistBuyingHistory;\n    bool public whiteListOnly;\n    uint public whiteListBuyableQuota;\n\n    EnumerableSet.AddressSet private publicBuyerList;\n    mapping (address => uint) public publicBuyingHistory;\n    uint public publicBuyableQuota;\n\n    bool public isMintingStarted;\n\n    string public imageUrl;\n\n    /*//////////////////////////////////////////////////////////////\n                              REVEALING STATE\n    //////////////////////////////////////////////////////////////*/\n    EnumerableSet.UintSet private nftIds;\n    bool public isRevealingStarted;\n\n\n    /*//////////////////////////////////////////////////////////////\n                                EVENTS\n    //////////////////////////////////////////////////////////////*/\n    event SetRandomGenerator(IRandomGenerator _newRandomGenerator);\n    event SetNftToken(IForcedOffline _newNft);\n    event Mint(address _to, uint tokenid_);\n    event MintMulti(address indexed _to, uint _amount);\n    event RevealRequested(uint indexed tokenId, address indexed user_);\n    event Reveal(uint indexed tokenId_, uint indexed nftId_);\n\n    /*//////////////////////////////////////////////////////////////\n                               MODIFIERS\n    //////////////////////////////////////////////////////////////*/\n    modifier onlyEOA() {\n        require(msg.sender == tx.origin, \"MysteryBox: not eoa\");\n        _;\n    }\n\n    /*//////////////////////////////////////////////////////////////\n                           CONSTRUCTOR\n    //////////////////////////////////////////////////////////////*/\n    /**\n     * @dev Grants `DEFAULT_ADMIN_ROLE` and `PAUSER_ROLE` to the\n     * account that deploys the contract.\n     */\n    constructor(IForcedOffline nftToken_, IRandomGenerator randomGenerator_, uint totalQuota_)\n    ERC721(\"ForcedOffline Mystery Box\", \"FOBOX\") {\n        _setupRole(DEFAULT_ADMIN_ROLE, _msgSender());\n        _setupRole(PAUSER_ROLE, _msgSender());\n        _setupRole(ADMIN_ROLE, _msgSender());\n\n        require(hasRole(ADMIN_ROLE, _msgSender()), \"MysteryBox: must have admin role to initialize.\");\n\n        nftToken = nftToken_;\n        randomGenerator = randomGenerator_;\n\n        whiteListBuyableQuota = 3;\n        publicBuyableQuota = 3;\n        totalMysteryBoxQuota = totalQuota_;\n\n        isMintingStarted = false;\n        whiteListOnly = true;\n        isRevealingStarted = false;\n    }\n\n\n    /*//////////////////////////////////////////////////////////////\n                          CONFIGURATION LOGIC\n    //////////////////////////////////////////////////////////////*/\n    function setRandomGenerator(IRandomGenerator randomGenerator_) onlyRole(ADMIN_ROLE) whenPaused public {\n        require(randomGenerator_ != IRandomGenerator(address(0)), \"The address of random generator is null\");\n        randomGenerator = randomGenerator_;\n        emit SetRandomGenerator(randomGenerator_);\n    }\n\n    function setNftToken(IForcedOffline nftToken_) onlyRole(ADMIN_ROLE) whenPaused public {\n        require(nftToken_ != IForcedOffline(address(0)), \"The address of IERC721 token is null\");\n        nftToken = nftToken_;\n        emit SetNftToken(nftToken_);\n    }\n\n    function setWhiteListBuyableQuota(uint whiteListBuyableQuota_) onlyRole(ADMIN_ROLE) whenPaused external {\n        whiteListBuyableQuota = whiteListBuyableQuota_;\n    }\n\n    function setPublicBuyableQuota(uint publicBuyableQuota_) onlyRole(ADMIN_ROLE) whenPaused external {\n        publicBuyableQuota = publicBuyableQuota_;\n    }\n\n    function setTotalQuota(uint totalQuota_) onlyRole(ADMIN_ROLE) whenPaused external {\n        totalMysteryBoxQuota = totalQuota_;\n    }\n\n    function setMerkleRoot(bytes32 merkleRoot_) onlyRole(ADMIN_ROLE) whenPaused external {\n        merkleRoot = merkleRoot_;\n    }\n\n    /*//////////////////////////////////////////////////////////////\n                               MINTING LOGIC\n    //////////////////////////////////////////////////////////////*/\n    function mintMulti(bytes32[] calldata merkleProof, uint amount) whenNotPaused onlyEOA external {\n        require(isMintingStarted, \"Minting has not started yet\");\n        require(amount > 0, \"MysteryBox: missing amount\");\n        totalMysteryBoxSold += amount;\n        require(totalMysteryBoxSold <= totalMysteryBoxQuota, \"MysteryBox: exceeded total mystery box buyable quota.\");\n\n        if (whiteListOnly) {\n            require(MerkleProof.verify(merkleProof, merkleRoot, toBytes32(msg.sender)) == true,\n                \"only whitelist allowed\");\n            require(whitelistBuyingHistory[_msgSender()] + amount <= whiteListBuyableQuota,\"Out of whitelist quota\");\n            whitelistBuyingHistory[_msgSender()] += amount;\n        } else {\n            require(publicBuyingHistory[_msgSender()] + amount <= publicBuyableQuota, \"Out of public sell quota\");\n            publicBuyingHistory[_msgSender()] += amount;\n            publicBuyerList.add(_msgSender());\n        }\n        for (uint i = 0; i < amount; i++) {\n            _mint(_msgSender(), _tokenIdTracker.current());\n            emit Mint(_msgSender(),_tokenIdTracker.current());\n            _tokenIdTracker.increment();\n        }\n        emit MintMulti(_msgSender(), amount);\n    }\n\n    function toggleWhiteListOnly() onlyRole(ADMIN_ROLE) whenPaused external {\n        if (whiteListOnly) {\n            whiteListOnly = false;\n        } else {\n            whiteListOnly = true;\n        }\n    }\n\n    /*//////////////////////////////////////////////////////////////\n                           REVEALING LOGIC\n    //////////////////////////////////////////////////////////////*/\n    function reveal(uint tokenId_) whenNotPaused onlyEOA external {\n        require(isRevealingStarted, \"Revealing has not started yet.\");\n        require(_isApprovedOrOwner(_msgSender(), tokenId_), \"MysteryBox: caller is not owner nor approved\");\n        randomGenerator.requestRandomNumber(tokenId_, _msgSender());\n        approve(address(randomGenerator), tokenId_);\n        emit RevealRequested(tokenId_, _msgSender());\n    }\n\n    function revealAll(uint from_, uint to_) onlyRole(ADMIN_ROLE) whenNotPaused external {\n        for(uint i = from_; i < to_; i++) {\n            if(!_exists(i)) {\n                continue;\n            }\n            address _user = ownerOf(i);\n            // no need user approval\n            _burn(i);\n            _fulfillReveal(i, _user, _randModulus(_user, block.timestamp, type(uint).max));\n        }\n    }\n\n    function runFulfillRandomness(uint256 tokenId_, address user_, uint256 randomness_) external {\n        require(_msgSender() == address(randomGenerator),\n            \"MysteryBox: only selected generator can call this method\"\n        );\n        fulfillRandomness(tokenId_, user_, randomness_);\n    }\n\n    function fulfillRandomness(uint256 tokenId_, address user_, uint256 randomness_) internal {\n        require(_isApprovedOrOwner(user_, tokenId_), \"MysteryBox: user is not owner nor approved\");\n        burn(tokenId_);\n        _fulfillReveal(tokenId_, user_, randomness_);\n    }\n\n    function _randModulus(address user_, uint seed_, uint mod_) internal view returns (uint) {\n        uint rand = uint(keccak256(abi.encodePacked(\n                block.timestamp,\n                block.difficulty,\n                mod_,\n                user_,\n                seed_,\n                _msgSender())\n            )) % mod_;\n        return rand;\n    }\n\n    function _fulfillReveal(uint256 tokenId_, address user_, uint256 randomness_) internal {\n        uint index = uint(keccak256(abi.encodePacked(randomness_))) % nftIds.length();\n        uint nftId = nftIds.at(index);\n        nftIds.remove(nftId);\n        nftToken.reveal(nftId);\n        IERC721(address(nftToken)).transferFrom(address(this), user_, nftId);\n        emit Reveal(tokenId_, nftId);\n    }\n\n    /*//////////////////////////////////////////////////////////////\n                            ADMIN LOGIC\n    //////////////////////////////////////////////////////////////*/\n    function transferAdmin(address account) external onlyRole(DEFAULT_ADMIN_ROLE) {\n        grantRole(DEFAULT_ADMIN_ROLE, account);\n        revokeRole(DEFAULT_ADMIN_ROLE, _msgSender());\n    }\n\n    function cleanPublicBuyHistory(uint amount) onlyRole(ADMIN_ROLE) whenPaused public returns (bool) {\n        uint length = publicBuyerList.length();\n        if (length < amount) {\n            amount = length;\n        }\n        for (uint i = 0; i < amount; i++) {\n            // modify fixed 0 position while iterating all keys\n            address buyer = publicBuyerList.at(0);\n            delete publicBuyingHistory[buyer];\n            publicBuyerList.remove(buyer);\n        }\n        return true;\n    }\n\n    function pause() public virtual {\n        require(hasRole(PAUSER_ROLE, _msgSender()), \"MysteryBox: must have pauser role to pause.\");\n        _pause();\n    }\n\n    function unpause() public virtual {\n        require(hasRole(PAUSER_ROLE, _msgSender()), \"MysteryBox: must have pauser role to unpause\");\n        _unpause();\n    }\n\n    function pullNFTs(address tokenAddress, address receivedAddress, uint amount) external onlyRole(DEFAULT_ADMIN_ROLE) {\n        require(receivedAddress != address(0));\n        require(tokenAddress != address(0));\n        uint balance = IERC721(tokenAddress).balanceOf(address(this));\n        if (balance < amount) {\n            amount = balance;\n        }\n        for (uint i = 0; i < amount; i++) {\n            uint tokenId = IERC721Enumerable(tokenAddress).tokenOfOwnerByIndex(address(this), 0);\n            IERC721(tokenAddress).safeTransferFrom(address(this), receivedAddress, tokenId);\n        }\n    }\n\n    function resetNftIds(uint[] calldata nftIds_) public whenPaused onlyRole(ADMIN_ROLE) {\n        clearNftIds();\n        for (uint i = 0; i < nftIds_.length; i++) {\n            nftIds.add(nftIds_[i]);\n        }\n    }\n\n    function initializeNftIds() external whenPaused onlyRole(ADMIN_ROLE) {\n        clearNftIds();\n        for (uint i = 0; i < totalMysteryBoxQuota; i++) {\n            nftIds.add(i);\n        }\n    }\n\n    function clearNftIds() internal {\n        uint length = nftIds.length();\n        for (uint i = 0; i < length; i++) {\n            nftIds.remove(nftIds.at(0));\n        }\n    }\n\n    /*//////////////////////////////////////////////////////////////\n                             URI LOGIC\n    //////////////////////////////////////////////////////////////*/\n    function tokenURI(uint256 tokenId_) public view override returns (string memory) {\n        require(_exists(tokenId_), 'URI query for nonexistent token.');\n        return constructTokenURI();\n    }\n\n    function constructTokenURI() public view returns (string memory) {\n        bytes memory metadata = abi.encodePacked('{\"name\":\"',\n            \"Ultra Mystery Box\",\n            '\",\"image\": \"',\n            imageUrl,\n            '\"}');\n\n        return string(\n            abi.encodePacked(\n                'data:application/json;base64,',\n                Base64.encode(\n                    bytes(metadata)\n                )\n            )\n        );\n    }\n\n    function setImageUrl(string calldata imageUrl_) external onlyRole(ADMIN_ROLE) {\n        imageUrl = imageUrl_;\n    }\n\n    /*//////////////////////////////////////////////////////////////\n                          ERC721 LOGIC\n    //////////////////////////////////////////////////////////////*/\n    function _beforeTokenTransfer(\n        address from,\n        address to,\n        uint256 tokenId,\n        uint256 batchSize\n    ) internal virtual override (ERC721, ERC721Enumerable, ERC721Pausable) {\n        super._beforeTokenTransfer(from, to, tokenId, batchSize);\n    }\n\n    function supportsInterface(bytes4 interfaceId)\n    public\n    view\n    virtual\n    override(AccessControlEnumerable, ERC721, ERC721Enumerable)\n    returns (bool)\n    {\n        return super.supportsInterface(interfaceId);\n    }\n\n    /*//////////////////////////////////////////////////////////////\n                          PHASES CONTROL LOGIC\n    //////////////////////////////////////////////////////////////*/\n    function startWhiteListMinting() onlyRole(ADMIN_ROLE) whenPaused external {\n        isMintingStarted = true;\n        whiteListOnly = true;\n    }\n\n    function startPublicMinting() onlyRole(ADMIN_ROLE) whenPaused  external {\n        isMintingStarted = true;\n        whiteListOnly = false;\n    }\n\n    function startRevealing() onlyRole(ADMIN_ROLE) whenPaused  external {\n        isRevealingStarted = true;\n    }\n\n    function endAll() onlyRole(ADMIN_ROLE) whenPaused  external {\n        isMintingStarted = false;\n        isRevealingStarted = false;\n    }\n\n    /*//////////////////////////////////////////////////////////////\n                           VIEW FUNCTIONS\n    //////////////////////////////////////////////////////////////*/\n    function totalSold() external view returns(uint) {\n        return totalMysteryBoxSold;\n    }\n\n    function totalQuota() external view returns(uint) {\n        return totalMysteryBoxQuota;\n    }\n\n    /*//////////////////////////////////////////////////////////////\n                           INTERNAL FUNCTIONS\n    //////////////////////////////////////////////////////////////*/\n    function toBytes32(address addr) pure internal returns (bytes32) {\n        return bytes32(uint256(uint160(addr)));\n    }\n}\n"
    }
  },
  "settings": {
    "optimizer": {
      "enabled": true,
      "runs": 200
    },
    "outputSelection": {
      "*": {
        "*": [
          "evm.bytecode",
          "evm.deployedBytecode",
          "devdoc",
          "userdoc",
          "metadata",
          "abi"
        ]
      }
    },
    "metadata": {
      "useLiteralContent": true
    },
    "libraries": {}
  }
}