// File: @thirdweb-dev/contracts/base/ERC20Base.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

import "../openzeppelin-presets/token/ERC20/extensions/ERC20Permit.sol";

import "../extension/ContractMetadata.sol";
import "../extension/Multicall.sol";
import "../extension/Ownable.sol";

/**
 *  The `ERC20Base` smart contract implements the ERC20 standard.
 *  It includes the following additions to standard ERC20 logic:
 *
 *      - Ability to mint & burn tokens via the provided `mint` & `burn` functions.
 *
 *      - Ownership of the contract, with the ability to restrict certain functions to
 *        only be called by the contract's owner.
 *
 *      - Multicall capability to perform multiple actions atomically
 *
 *      - EIP 2612 compliance: See {ERC20-permit} method, which can be used to change an account's ERC20 allowance by
 *                             presenting a message signed by the account.
 */

contract ERC20Base is ContractMetadata, Multicall, Ownable, ERC20Permit {
    /*//////////////////////////////////////////////////////////////
                            Constructor
    //////////////////////////////////////////////////////////////*/

    constructor(string memory _name, string memory _symbol) ERC20Permit(_name, _symbol) {
        _setupOwner(msg.sender);
    }

    /*//////////////////////////////////////////////////////////////
                            Minting logic
    //////////////////////////////////////////////////////////////*/

    /**
     *  @notice          Lets an authorized address mint tokens to a recipient.
     *  @dev             The logic in the `_canMint` function determines whether the caller is authorized to mint tokens.
     *
     *  @param _to       The recipient of the tokens to mint.
     *  @param _amount   Quantity of tokens to mint.
     */
    function mintTo(address _to, uint256 _amount) public virtual {
        require(_canMint(), "Not authorized to mint.");
        require(_amount != 0, "Minting zero tokens.");

        _mint(_to, _amount);
    }

    /**
     *  @notice          Lets an owner a given amount of their tokens.
     *  @dev             Caller should own the `_amount` of tokens.
     *
     *  @param _amount   The number of tokens to burn.
     */
    function burn(uint256 _amount) external virtual {
        require(balanceOf(msg.sender) >= _amount, "not enough balance");
        _burn(msg.sender, _amount);
    }

    /*//////////////////////////////////////////////////////////////
                        Internal (overrideable) functions
    //////////////////////////////////////////////////////////////*/

    /// @dev Returns whether contract metadata can be set in the given execution context.
    function _canSetContractURI() internal view virtual override returns (bool) {
        return msg.sender == owner();
    }

    /// @dev Returns whether tokens can be minted in the given execution context.
    function _canMint() internal view virtual returns (bool) {
        return msg.sender == owner();
    }

    /// @dev Returns whether owner can be set in the given execution context.
    function _canSetOwner() internal view virtual override returns (bool) {
        return msg.sender == owner();
    }
}

// File: @thirdweb-dev/contracts/eip/interface/IERC20.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
interface IERC20 {
    function totalSupply() external view returns (uint256);

    function balanceOf(address who) external view returns (uint256);

    function allowance(address owner, address spender) external view returns (uint256);

    function transfer(address to, uint256 value) external returns (bool);

    function approve(address spender, uint256 value) external returns (bool);

    function transferFrom(
        address from,
        address to,
        uint256 value
    ) external returns (bool);

    event Transfer(address indexed from, address indexed to, uint256 value);

    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// File: @thirdweb-dev/contracts/eip/interface/IERC20Metadata.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/**
 * @title ERC20Metadata interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
interface IERC20Metadata {
    function name() external view returns (string memory);

    function symbol() external view returns (string memory);

    function decimals() external view returns (uint8);
}

// File: @thirdweb-dev/contracts/eip/interface/IERC20Permit.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)

pragma solidity ^0.8.0;

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

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

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

// File: @thirdweb-dev/contracts/extension/ContractMetadata.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

import "./interface/IContractMetadata.sol";

/**
 *  @title   Contract Metadata
 *  @notice  Thirdweb's `ContractMetadata` is a contract extension for any base contracts. It lets you set a metadata URI
 *           for you contract.
 *           Additionally, `ContractMetadata` is necessary for NFT contracts that want royalties to get distributed on OpenSea.
 */

abstract contract ContractMetadata is IContractMetadata {
    /// @notice Returns the contract metadata URI.
    string public override contractURI;

    /**
     *  @notice         Lets a contract admin set the URI for contract-level metadata.
     *  @dev            Caller should be authorized to setup contractURI, e.g. contract admin.
     *                  See {_canSetContractURI}.
     *                  Emits {ContractURIUpdated Event}.
     *
     *  @param _uri     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     */
    function setContractURI(string memory _uri) external override {
        if (!_canSetContractURI()) {
            revert("Not authorized");
        }

        _setupContractURI(_uri);
    }

    /// @dev Lets a contract admin set the URI for contract-level metadata.
    function _setupContractURI(string memory _uri) internal {
        string memory prevURI = contractURI;
        contractURI = _uri;

        emit ContractURIUpdated(prevURI, _uri);
    }

    /// @dev Returns whether contract metadata can be set in the given execution context.
    function _canSetContractURI() internal view virtual returns (bool);
}

// File: @thirdweb-dev/contracts/extension/Multicall.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/Multicall.sol)

pragma solidity ^0.8.0;

import "../lib/TWAddress.sol";
import "./interface/IMulticall.sol";

/**
 * @dev Provides a function to batch together multiple calls in a single external call.
 *
 * _Available since v4.1._
 */
contract Multicall is IMulticall {
    /**
     *  @notice Receives and executes a batch of function calls on this contract.
     *  @dev Receives and executes a batch of function calls on this contract.
     *
     *  @param data The bytes data that makes up the batch of function calls to execute.
     *  @return results The bytes data that makes up the result of the batch of function calls executed.
     */
    function multicall(bytes[] calldata data) external virtual override returns (bytes[] memory results) {
        results = new bytes[](data.length);
        for (uint256 i = 0; i < data.length; i++) {
            results[i] = TWAddress.functionDelegateCall(address(this), data[i]);
        }
        return results;
    }
}

// File: @thirdweb-dev/contracts/extension/Ownable.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

import "./interface/IOwnable.sol";

/**
 *  @title   Ownable
 *  @notice  Thirdweb's `Ownable` is a contract extension to be used with any base contract. It exposes functions for setting and reading
 *           who the 'owner' of the inheriting smart contract is, and lets the inheriting contract perform conditional logic that uses
 *           information about who the contract's owner is.
 */

abstract contract Ownable is IOwnable {
    /// @dev Owner of the contract (purpose: OpenSea compatibility)
    address private _owner;

    /// @dev Reverts if caller is not the owner.
    modifier onlyOwner() {
        if (msg.sender != _owner) {
            revert("Not authorized");
        }
        _;
    }

    /**
     *  @notice Returns the owner of the contract.
     */
    function owner() public view override returns (address) {
        return _owner;
    }

    /**
     *  @notice Lets an authorized wallet set a new owner for the contract.
     *  @param _newOwner The address to set as the new owner of the contract.
     */
    function setOwner(address _newOwner) external override {
        if (!_canSetOwner()) {
            revert("Not authorized");
        }
        _setupOwner(_newOwner);
    }

    /// @dev Lets a contract admin set a new owner for the contract. The new owner must be a contract admin.
    function _setupOwner(address _newOwner) internal {
        address _prevOwner = _owner;
        _owner = _newOwner;

        emit OwnerUpdated(_prevOwner, _newOwner);
    }

    /// @dev Returns whether owner can be set in the given execution context.
    function _canSetOwner() internal view virtual returns (bool);
}

// File: @thirdweb-dev/contracts/extension/Permissions.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

import "./interface/IPermissions.sol";
import "../lib/TWStrings.sol";

/**
 *  @title   Permissions
 *  @dev     This contracts provides extending-contracts with role-based access control mechanisms
 */
contract Permissions is IPermissions {
    /// @dev Map from keccak256 hash of a role => a map from address => whether address has role.
    mapping(bytes32 => mapping(address => bool)) private _hasRole;

    /// @dev Map from keccak256 hash of a role to role admin. See {getRoleAdmin}.
    mapping(bytes32 => bytes32) private _getRoleAdmin;

    /// @dev Default admin role for all roles. Only accounts with this role can grant/revoke other roles.
    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;

    /// @dev Modifier that checks if an account has the specified role; reverts otherwise.
    modifier onlyRole(bytes32 role) {
        _checkRole(role, msg.sender);
        _;
    }

    /**
     *  @notice         Checks whether an account has a particular role.
     *  @dev            Returns `true` if `account` has been granted `role`.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account for which the role is being checked.
     */
    function hasRole(bytes32 role, address account) public view override returns (bool) {
        return _hasRole[role][account];
    }

    /**
     *  @notice         Checks whether an account has a particular role;
     *                  role restrictions can be swtiched on and off.
     *
     *  @dev            Returns `true` if `account` has been granted `role`.
     *                  Role restrictions can be swtiched on and off:
     *                      - If address(0) has ROLE, then the ROLE restrictions
     *                        don't apply.
     *                      - If address(0) does not have ROLE, then the ROLE
     *                        restrictions will apply.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account for which the role is being checked.
     */
    function hasRoleWithSwitch(bytes32 role, address account) public view returns (bool) {
        if (!_hasRole[role][address(0)]) {
            return _hasRole[role][account];
        }

        return true;
    }

    /**
     *  @notice         Returns the admin role that controls the specified role.
     *  @dev            See {grantRole} and {revokeRole}.
     *                  To change a role's admin, use {_setRoleAdmin}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     */
    function getRoleAdmin(bytes32 role) external view override returns (bytes32) {
        return _getRoleAdmin[role];
    }

    /**
     *  @notice         Grants a role to an account, if not previously granted.
     *  @dev            Caller must have admin role for the `role`.
     *                  Emits {RoleGranted Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account to which the role is being granted.
     */
    function grantRole(bytes32 role, address account) public virtual override {
        _checkRole(_getRoleAdmin[role], msg.sender);
        if (_hasRole[role][account]) {
            revert("Can only grant to non holders");
        }
        _setupRole(role, account);
    }

    /**
     *  @notice         Revokes role from an account.
     *  @dev            Caller must have admin role for the `role`.
     *                  Emits {RoleRevoked Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account from which the role is being revoked.
     */
    function revokeRole(bytes32 role, address account) public virtual override {
        _checkRole(_getRoleAdmin[role], msg.sender);
        _revokeRole(role, account);
    }

    /**
     *  @notice         Revokes role from the account.
     *  @dev            Caller must have the `role`, with caller being the same as `account`.
     *                  Emits {RoleRevoked Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account from which the role is being revoked.
     */
    function renounceRole(bytes32 role, address account) public virtual override {
        if (msg.sender != account) {
            revert("Can only renounce for self");
        }
        _revokeRole(role, account);
    }

    /// @dev Sets `adminRole` as `role`'s admin role.
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
        bytes32 previousAdminRole = _getRoleAdmin[role];
        _getRoleAdmin[role] = adminRole;
        emit RoleAdminChanged(role, previousAdminRole, adminRole);
    }

    /// @dev Sets up `role` for `account`
    function _setupRole(bytes32 role, address account) internal virtual {
        _hasRole[role][account] = true;
        emit RoleGranted(role, account, msg.sender);
    }

    /// @dev Revokes `role` from `account`
    function _revokeRole(bytes32 role, address account) internal virtual {
        _checkRole(role, account);
        delete _hasRole[role][account];
        emit RoleRevoked(role, account, msg.sender);
    }

    /// @dev Checks `role` for `account`. Reverts with a message including the required role.
    function _checkRole(bytes32 role, address account) internal view virtual {
        if (!_hasRole[role][account]) {
            revert(
                string(
                    abi.encodePacked(
                        "Permissions: account ",
                        TWStrings.toHexString(uint160(account), 20),
                        " is missing role ",
                        TWStrings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }

    /// @dev Checks `role` for `account`. Reverts with a message including the required role.
    function _checkRoleWithSwitch(bytes32 role, address account) internal view virtual {
        if (!hasRoleWithSwitch(role, account)) {
            revert(
                string(
                    abi.encodePacked(
                        "Permissions: account ",
                        TWStrings.toHexString(uint160(account), 20),
                        " is missing role ",
                        TWStrings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }
}

// File: @thirdweb-dev/contracts/extension/PermissionsEnumerable.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

import "./interface/IPermissionsEnumerable.sol";
import "./Permissions.sol";

/**
 *  @title   PermissionsEnumerable
 *  @dev     This contracts provides extending-contracts with role-based access control mechanisms.
 *           Also provides interfaces to view all members with a given role, and total count of members.
 */
contract PermissionsEnumerable is IPermissionsEnumerable, Permissions {
    /**
     *  @notice A data structure to store data of members for a given role.
     *
     *  @param index    Current index in the list of accounts that have a role.
     *  @param members  map from index => address of account that has a role
     *  @param indexOf  map from address => index which the account has.
     */
    struct RoleMembers {
        uint256 index;
        mapping(uint256 => address) members;
        mapping(address => uint256) indexOf;
    }

    /// @dev map from keccak256 hash of a role to its members' data. See {RoleMembers}.
    mapping(bytes32 => RoleMembers) private roleMembers;

    /**
     *  @notice         Returns the role-member from a list of members for a role,
     *                  at a given index.
     *  @dev            Returns `member` who has `role`, at `index` of role-members list.
     *                  See struct {RoleMembers}, and mapping {roleMembers}
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param index    Index in list of current members for the role.
     *
     *  @return member  Address of account that has `role`
     */
    function getRoleMember(bytes32 role, uint256 index) external view override returns (address member) {
        uint256 currentIndex = roleMembers[role].index;
        uint256 check;

        for (uint256 i = 0; i < currentIndex; i += 1) {
            if (roleMembers[role].members[i] != address(0)) {
                if (check == index) {
                    member = roleMembers[role].members[i];
                    return member;
                }
                check += 1;
            } else if (hasRole(role, address(0)) && i == roleMembers[role].indexOf[address(0)]) {
                check += 1;
            }
        }
    }

    /**
     *  @notice         Returns total number of accounts that have a role.
     *  @dev            Returns `count` of accounts that have `role`.
     *                  See struct {RoleMembers}, and mapping {roleMembers}
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *
     *  @return count   Total number of accounts that have `role`
     */
    function getRoleMemberCount(bytes32 role) external view override returns (uint256 count) {
        uint256 currentIndex = roleMembers[role].index;

        for (uint256 i = 0; i < currentIndex; i += 1) {
            if (roleMembers[role].members[i] != address(0)) {
                count += 1;
            }
        }
        if (hasRole(role, address(0))) {
            count += 1;
        }
    }

    /// @dev Revokes `role` from `account`, and removes `account` from {roleMembers}
    ///      See {_removeMember}
    function _revokeRole(bytes32 role, address account) internal override {
        super._revokeRole(role, account);
        _removeMember(role, account);
    }

    /// @dev Grants `role` to `account`, and adds `account` to {roleMembers}
    ///      See {_addMember}
    function _setupRole(bytes32 role, address account) internal override {
        super._setupRole(role, account);
        _addMember(role, account);
    }

    /// @dev adds `account` to {roleMembers}, for `role`
    function _addMember(bytes32 role, address account) internal {
        uint256 idx = roleMembers[role].index;
        roleMembers[role].index += 1;

        roleMembers[role].members[idx] = account;
        roleMembers[role].indexOf[account] = idx;
    }

    /// @dev removes `account` from {roleMembers}, for `role`
    function _removeMember(bytes32 role, address account) internal {
        uint256 idx = roleMembers[role].indexOf[account];

        delete roleMembers[role].members[idx];
        delete roleMembers[role].indexOf[account];
    }
}

// File: @thirdweb-dev/contracts/extension/interface/IContractMetadata.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/**
 *  Thirdweb's `ContractMetadata` is a contract extension for any base contracts. It lets you set a metadata URI
 *  for you contract.
 *
 *  Additionally, `ContractMetadata` is necessary for NFT contracts that want royalties to get distributed on OpenSea.
 */

interface IContractMetadata {
    /// @dev Returns the metadata URI of the contract.
    function contractURI() external view returns (string memory);

    /**
     *  @dev Sets contract URI for the storefront-level metadata of the contract.
     *       Only module admin can call this function.
     */
    function setContractURI(string calldata _uri) external;

    /// @dev Emitted when the contract URI is updated.
    event ContractURIUpdated(string prevURI, string newURI);
}

// File: @thirdweb-dev/contracts/extension/interface/IMulticall.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/Multicall.sol)

pragma solidity ^0.8.0;

/**
 * @dev Provides a function to batch together multiple calls in a single external call.
 *
 * _Available since v4.1._
 */
interface IMulticall {
    /**
     * @dev Receives and executes a batch of function calls on this contract.
     */
    function multicall(bytes[] calldata data) external returns (bytes[] memory results);
}

// File: @thirdweb-dev/contracts/extension/interface/IOwnable.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/**
 *  Thirdweb's `Ownable` is a contract extension to be used with any base contract. It exposes functions for setting and reading
 *  who the 'owner' of the inheriting smart contract is, and lets the inheriting contract perform conditional logic that uses
 *  information about who the contract's owner is.
 */

interface IOwnable {
    /// @dev Returns the owner of the contract.
    function owner() external view returns (address);

    /// @dev Lets a module admin set a new owner for the contract. The new owner must be a module admin.
    function setOwner(address _newOwner) external;

    /// @dev Emitted when a new Owner is set.
    event OwnerUpdated(address indexed prevOwner, address indexed newOwner);
}

// File: @thirdweb-dev/contracts/extension/interface/IPermissions.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/**
 * @dev External interface of AccessControl declared to support ERC165 detection.
 */
interface IPermissions {
    /**
     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
     *
     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
     * {RoleAdminChanged} not being emitted signaling this.
     *
     * _Available since v3.1._
     */
    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);

    /**
     * @dev Emitted when `account` is granted `role`.
     *
     * `sender` is the account that originated the contract call, an admin role
     * bearer except when using {AccessControl-_setupRole}.
     */
    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Emitted when `account` is revoked `role`.
     *
     * `sender` is the account that originated the contract call:
     *   - if using `revokeRole`, it is the admin role bearer
     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
     */
    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) external view returns (bool);

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {AccessControl-_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) external view returns (bytes32);

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function grantRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function revokeRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) external;
}

// File: @thirdweb-dev/contracts/extension/interface/IPermissionsEnumerable.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

import "./IPermissions.sol";

/**
 * @dev External interface of AccessControlEnumerable declared to support ERC165 detection.
 */
interface IPermissionsEnumerable is IPermissions {
    /**
     * @dev Returns one of the accounts that have `role`. `index` must be a
     * value between 0 and {getRoleMemberCount}, non-inclusive.
     *
     * Role bearers are not sorted in any particular way, and their ordering may
     * change at any point.
     *
     * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
     * you perform all queries on the same block. See the following
     * [forum post](https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296)
     * for more information.
     */
    function getRoleMember(bytes32 role, uint256 index) external view returns (address);

    /**
     * @dev Returns the number of accounts that have `role`. Can be used
     * together with {getRoleMember} to enumerate all bearers of a role.
     */
    function getRoleMemberCount(bytes32 role) external view returns (uint256);
}

// File: @thirdweb-dev/contracts/lib/TWAddress.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)

pragma solidity ^0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library TWAddress {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

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

        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

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

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

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

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

        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

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

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

        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

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

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

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// File: @thirdweb-dev/contracts/lib/TWStrings.sol



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

pragma solidity ^0.8.0;

/**
 * @dev String operations.
 */
library TWStrings {
    bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";

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

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

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        if (value == 0) {
            return "0x00";
        }
        uint256 temp = value;
        uint256 length = 0;
        while (temp != 0) {
            length++;
            temp >>= 8;
        }
        return toHexString(value, length);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        bytes memory buffer = new bytes(2 * length + 2);
        buffer[0] = "0";
        buffer[1] = "x";
        for (uint256 i = 2 * length + 1; i > 1; --i) {
            buffer[i] = _HEX_SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }
}

// File: @thirdweb-dev/contracts/openzeppelin-presets/token/ERC20/ERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;

import "../../../eip/interface/IERC20.sol";
import "../../../eip/interface/IERC20Metadata.sol";
import "../../utils/Context.sol";

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

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

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

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

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

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless this function is
     * overridden;
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

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

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

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

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

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

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

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

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

        return true;
    }

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

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
        }
        _balances[to] += amount;

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

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

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

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

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

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

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

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
        }
        _totalSupply -= amount;

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

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

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

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

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

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

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

// File: @thirdweb-dev/contracts/openzeppelin-presets/token/ERC20/extensions/ERC20Permit.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-ERC20Permit.sol)

pragma solidity ^0.8.0;

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

/**
 * @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * _Available since v3.4._
 */
abstract contract ERC20Permit is ERC20, IERC20Permit {
    using Counters for Counters.Counter;

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

    // solhint-disable-next-line var-name-mixedcase
    bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;

    // solhint-disable-next-line var-name-mixedcase
    uint256 private immutable _CACHED_CHAIN_ID;

    // solhint-disable-next-line var-name-mixedcase
    address private immutable _CACHED_THIS;

    // solhint-disable-next-line var-name-mixedcase
    bytes32 private immutable _PERMIT_TYPEHASH =
        keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");

    /**
     * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
     *
     * It's a good idea to use the same `name` that is defined as the ERC20 token name.
     */
    constructor(string memory name_, string memory symbol_) ERC20(name_, symbol_) {
        _CACHED_CHAIN_ID = block.chainid;
        _CACHED_THIS = address(this);
        _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator();
    }

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

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

        bytes32 hash = ECDSA.toTypedDataHash(DOMAIN_SEPARATOR(), structHash);

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

        _approve(owner, spender, value);
    }

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

    /**
     * @dev See {IERC20Permit-DOMAIN_SEPARATOR}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() public view override returns (bytes32) {
        if (address(this) == _CACHED_THIS && block.chainid == _CACHED_CHAIN_ID) {
            return _CACHED_DOMAIN_SEPARATOR;
        } else {
            return _buildDomainSeparator();
        }
    }

    function _buildDomainSeparator() private view returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                    keccak256(bytes(name())),
                    keccak256("1"),
                    block.chainid,
                    address(this)
                )
            );
    }

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

// File: @thirdweb-dev/contracts/openzeppelin-presets/utils/Context.sol



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

pragma solidity ^0.8.0;

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

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

// File: @thirdweb-dev/contracts/openzeppelin-presets/utils/Counters.sol



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

pragma solidity ^0.8.0;

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

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

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

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

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

// File: @thirdweb-dev/contracts/openzeppelin-presets/utils/cryptography/ECDSA.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/cryptography/ECDSA.sol)

pragma solidity ^0.8.0;

import "../../../lib/TWStrings.sol";

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

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

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature` or error string. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     *
     * Documentation for signature generation:
     * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
     * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
        // Check the signature length
        // - case 65: r,s,v signature (standard)
        // - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
        if (signature.length == 65) {
            bytes32 r;
            bytes32 s;
            uint8 v;
            // ecrecover takes the signature parameters, and the only way to get them
            // currently is to use assembly.
            assembly {
                r := mload(add(signature, 0x20))
                s := mload(add(signature, 0x40))
                v := byte(0, mload(add(signature, 0x60)))
            }
            return tryRecover(hash, v, r, s);
        } else if (signature.length == 64) {
            bytes32 r;
            bytes32 vs;
            // ecrecover takes the signature parameters, and the only way to get them
            // currently is to use assembly.
            assembly {
                r := mload(add(signature, 0x20))
                vs := mload(add(signature, 0x40))
            }
            return tryRecover(hash, r, vs);
        } else {
            return (address(0), RecoverError.InvalidSignatureLength);
        }
    }

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

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

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

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

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

        return (signer, RecoverError.NoError);
    }

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

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

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

    /**
     * @dev Returns an Ethereum Signed Typed Data, created from a
     * `domainSeparator` and a `structHash`. This produces hash corresponding
     * to the one signed with the
     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
     * JSON-RPC method as part of EIP-712.
     *
     * See {recover}.
     */
    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
    }
}

// File: @thirdweb-dev/contracts/openzeppelin-presets/utils/cryptography/EIP712.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/cryptography/draft-EIP712.sol)

pragma solidity ^0.8.0;

import "./ECDSA.sol";

/**
 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
 *
 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
 *
 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
 * ({_hashTypedDataV4}).
 *
 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
 * the chain id to protect against replay attacks on an eventual fork of the chain.
 *
 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
 *
 * _Available since v3.4._
 */
abstract contract EIP712 {
    /* solhint-disable var-name-mixedcase */
    // Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
    // invalidate the cached domain separator if the chain id changes.
    bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;
    uint256 private immutable _CACHED_CHAIN_ID;
    address private immutable _CACHED_THIS;

    bytes32 private immutable _HASHED_NAME;
    bytes32 private immutable _HASHED_VERSION;
    bytes32 private immutable _TYPE_HASH;

    /* solhint-enable var-name-mixedcase */

    /**
     * @dev Initializes the domain separator and parameter caches.
     *
     * The meaning of `name` and `version` is specified in
     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
     *
     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
     * - `version`: the current major version of the signing domain.
     *
     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
     * contract upgrade].
     */
    constructor(string memory name, string memory version) {
        bytes32 hashedName = keccak256(bytes(name));
        bytes32 hashedVersion = keccak256(bytes(version));
        bytes32 typeHash = keccak256(
            "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
        );
        _HASHED_NAME = hashedName;
        _HASHED_VERSION = hashedVersion;
        _CACHED_CHAIN_ID = block.chainid;
        _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion);
        _CACHED_THIS = address(this);
        _TYPE_HASH = typeHash;
    }

    /**
     * @dev Returns the domain separator for the current chain.
     */
    function _domainSeparatorV4() internal view returns (bytes32) {
        if (address(this) == _CACHED_THIS && block.chainid == _CACHED_CHAIN_ID) {
            return _CACHED_DOMAIN_SEPARATOR;
        } else {
            return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION);
        }
    }

    function _buildDomainSeparator(
        bytes32 typeHash,
        bytes32 nameHash,
        bytes32 versionHash
    ) private view returns (bytes32) {
        return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
    }

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

// File: @thirdweb-dev/contracts/openzeppelin-presets/utils/math/SafeMath.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (utils/math/SafeMath.sol)

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

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

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

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

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

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

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

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

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

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

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

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

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

// File: contracts/XMT.sol



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

import "@thirdweb-dev/contracts/base/ERC20Base.sol";
import "@thirdweb-dev/contracts/extension/PermissionsEnumerable.sol";
import "@thirdweb-dev/contracts/openzeppelin-presets/utils/math/SafeMath.sol";

contract Contract is ERC20Base, PermissionsEnumerable {
    
    bool _mintLocked = false;

    bytes32 public constant MANAGER_ROLE = keccak256("MANAGER_ROLE");

    using SafeMath for uint256;

    struct VestingSchedule{
        bool initialized;
        // beneficiary of tokens after they are released
        address  beneficiary;
        // cliff period in seconds
        uint256  cliff;
        // start time of the vesting period
        uint256  start;
        // duration of the vesting period in seconds
        uint256  duration;
        // duration of a slice period for the vesting in seconds
        uint256 slicePeriodSeconds;
        // whether or not the vesting is revocable
        bool  revocable;
        // total amount of tokens to be released at the end of the vesting
        uint256 amountTotal;
        // amount of tokens released
        uint256  released;
        // whether or not the vesting has been revoked
        bool revoked;
    }

    bytes32[] private vestingSchedulesIds;
    mapping(bytes32 => VestingSchedule) private vestingSchedules;
    uint256 private vestingSchedulesTotalAmount;
    mapping(address => uint256) private holdersVestingCount;

    constructor(
        string memory _name,
        string memory _symbol,
        uint256 initialSupply
    )
        ERC20Base(
            _name,
            _symbol
        )
    {
        _mint(_msgSender(), initialSupply);
        _setupRole(DEFAULT_ADMIN_ROLE, _msgSender());
        _setupRole(MANAGER_ROLE, _msgSender());

        _mintLocked = true;
    }
    
    event Released(uint256 amount);
    event Revoked(bytes32);
    event VestingCreated(bytes32, address, uint256);

    /**
    * @dev Reverts if no vesting schedule matches the passed identifier.
    */
    modifier onlyIfVestingScheduleExists(bytes32 vestingScheduleId) {
        require(vestingSchedules[vestingScheduleId].initialized == true, "not intialized");
        _;
    }

    /**
    * @dev Reverts if the vesting schedule does not exist or has been revoked.
    */
    modifier onlyIfVestingScheduleNotRevoked(bytes32 vestingScheduleId) {
        require(vestingSchedules[vestingScheduleId].initialized == true, "not intialized");
        require(vestingSchedules[vestingScheduleId].revoked == false, "already revoked");
        _;
    }

    /**
    * @dev Returns the number of vesting schedules associated to a beneficiary.
    * @return the number of vesting schedules
    */
    function getVestingSchedulesCountByBeneficiary(address _beneficiary)
    public
    view
    returns(uint256){
        return holdersVestingCount[_beneficiary];
    }

    /**
    * @dev Returns the vesting schedule id at the given index.
    * @return the vesting id
    */
    function getVestingIdAtIndex(uint256 index)
    external
    view
    returns(bytes32){
        require(index < getVestingSchedulesCount(), "index out of bounds");
        return vestingSchedulesIds[index];
    }

    /**
    * @notice Returns the vesting schedule information for a given holder and index.
    * @return the vesting schedule structure information
    */
    function getVestingScheduleByAddressAndIndex(address holder, uint256 index)
    public
    view
    returns(VestingSchedule memory){
        return getVestingSchedule(computeVestingScheduleIdForAddressAndIndex(holder, index));
    }


    /**
    * @notice Returns the total amount of vesting schedules.
    * @return the total amount of vesting schedules
    */
    function getVestingSchedulesTotalAmount()
    external
    view
    returns(uint256){
        return vestingSchedulesTotalAmount;
    }

    // /**
    // * @dev Returns the address of the ERC20 token managed by the vesting contract.
    // */
    // function getToken()
    // external
    // view
    // returns(address){
    //     return address(_token);
    // }

    /**
    * @notice Creates a new vesting schedule for a beneficiary.
    * @param _beneficiary address of the beneficiary to whom vested tokens are transferred
    * @param _start start time of the vesting period
    * @param _cliff duration in seconds of the cliff in which tokens will begin to vest
    * @param _duration duration in seconds of the period in which the tokens will vest
    * @param _slicePeriodSeconds duration of a slice period for the vesting in seconds
    * @param _revocable whether the vesting is revocable or not
    * @param _amount total amount of tokens to be released at the end of the vesting
    */
    function createVestingSchedule(
        address _beneficiary,
        uint256 _start,
        uint256 _cliff,
        uint256 _duration,
        uint256 _slicePeriodSeconds,
        bool _revocable,
        uint256 _amount
    )
        public
        {
        // require(
        //     this.getWithdrawableAmount() >= _amount,
        //     "cannot create vesting schedule because not sufficient tokens"
        // );
        require(hasRole(MANAGER_ROLE, _msgSender()), "unauthorized");
        require(_duration > 0, "duration must be > 0");
        require(_amount > 0, "amount must be > 0");
        require(_cliff <= _duration, "invalid cliff");
        require(_slicePeriodSeconds >= 1, "slicePeriodSeconds must be >= 1");

        bytes32 vestingScheduleId = this.computeNextVestingScheduleIdForHolder(_beneficiary);
        uint256 cliff = _start.add(_cliff);
        vestingSchedules[vestingScheduleId] = VestingSchedule(
            true,
            _beneficiary,
            cliff,
            _start,
            _duration,
            _slicePeriodSeconds,
            _revocable,
            _amount,
            0,
            false
        );
        vestingSchedulesTotalAmount = vestingSchedulesTotalAmount.add(_amount);
        vestingSchedulesIds.push(vestingScheduleId);
        uint256 currentVestingCount = holdersVestingCount[_beneficiary];
        holdersVestingCount[_beneficiary] = currentVestingCount.add(1);

        // todo: add event emit
        emit VestingCreated(vestingScheduleId, _beneficiary, _amount);
    }

    /**
    * @notice Revokes the vesting schedule for given identifier.
    * @param vestingScheduleId the vesting schedule identifier
    */
    function revoke(bytes32 vestingScheduleId)
        public
        onlyIfVestingScheduleNotRevoked(vestingScheduleId){
        require(hasRole(MANAGER_ROLE, _msgSender()), "unauthorized");
        VestingSchedule storage vestingSchedule = vestingSchedules[vestingScheduleId];
        require(vestingSchedule.revocable == true, "vesting is not revocable");

        uint256 unreleased = vestingSchedule.amountTotal.sub(vestingSchedule.released);
        vestingSchedulesTotalAmount = vestingSchedulesTotalAmount.sub(unreleased);
        vestingSchedule.revoked = true;

        // todo: add event emit
        emit Revoked(vestingScheduleId);
    }

    /**
    * @dev Returns the number of vesting schedules managed by this contract.
    * @return the number of vesting schedules
    */
    function getVestingSchedulesCount()
        public
        view
        returns(uint256){
        return vestingSchedulesIds.length;
    }

    function computeLockedAmount(address holder)
        public
        view
        returns(uint256) {
        uint count = getVestingSchedulesCountByBeneficiary(holder);
        require(count <= getVestingSchedulesCount(), "index out of bounds");
        uint totalLocked = 0;
        for (uint i = 0; i < count; i++) {
            VestingSchedule memory vestingSchedule = getVestingScheduleByAddressAndIndex(holder, i);
            
            uint256 lockedAmount = _computeLockedAmount(vestingSchedule);
            totalLocked = totalLocked.add(lockedAmount);
        }

        return totalLocked;
    }

    /**
    * @notice Returns the vesting schedule information for a given identifier.
    * @return the vesting schedule structure information
    */
    function getVestingSchedule(bytes32 vestingScheduleId)
        public
        view
        returns(VestingSchedule memory){
        return vestingSchedules[vestingScheduleId];
    }

    /**
    * @dev Returns the amount of tokens that can be withdrawn by the owner.
    * @return the amount of tokens
    */
    // function getWithdrawableAmount()
    //     public
    //     view
    //     returns(uint256){
    //     // return _token.balanceOf(address(this)).sub(vestingSchedulesTotalAmount);
    //     return _vestedTokenPool.sub(vestingSchedulesTotalAmount);
    // }

    /**
    * @dev Computes the next vesting schedule identifier for a given holder address.
    */
    function computeNextVestingScheduleIdForHolder(address holder)
        public
        view
        returns(bytes32){
        return computeVestingScheduleIdForAddressAndIndex(holder, holdersVestingCount[holder]);
    }

    /**
    * @dev Returns the last vesting schedule for a given holder address.
    */
    function getLastVestingScheduleForHolder(address holder)
        public
        view
        returns(VestingSchedule memory){
        return vestingSchedules[computeVestingScheduleIdForAddressAndIndex(holder, holdersVestingCount[holder] - 1)];
    }

    /**
    * @dev Computes the vesting schedule identifier for an address and an index.
    */
    function computeVestingScheduleIdForAddressAndIndex(address holder, uint256 index)
        public
        pure
        returns(bytes32){
        return keccak256(abi.encodePacked(holder, index));
    }

    function _computeLockedAmount(VestingSchedule memory vestingSchedule)
    internal
    view
    returns(uint256){
        uint256 currentTime = getCurrentTime();
        if (vestingSchedule.revoked == true) {
            return 0;
        } else if ((currentTime < vestingSchedule.cliff)) {
            return vestingSchedule.amountTotal;
        } else if (currentTime >= vestingSchedule.start.add(vestingSchedule.duration)) {
            return 0;
        } else {
            uint256 timeFromStart = currentTime.sub(vestingSchedule.start);
            uint secondsPerSlice = vestingSchedule.slicePeriodSeconds;
            uint256 vestedSlicePeriods = timeFromStart.div(secondsPerSlice);
            uint256 vestedSeconds = vestedSlicePeriods.mul(secondsPerSlice);
            uint256 vestedAmount = vestingSchedule.amountTotal.mul(vestedSeconds).div(vestingSchedule.duration);
            return vestingSchedule.amountTotal.sub(vestedAmount);
        }
    }

    function getCurrentTime()
        internal
        virtual
        view
        returns(uint256){
        return block.timestamp;
    }

    function _beforeTokenTransfer(address from, address to, uint256 amount) internal override virtual {
        uint totalLocked = computeLockedAmount(from);
        
        if (from != address(0)) require(amount <= balanceOf(from).sub(totalLocked), 'check vesting or balance');
        super._beforeTokenTransfer(from, to, amount);
    }

    function vestedTransfer(
        address _recipient, 
        uint256 _amount, 
        uint256 _start, 
        uint256 _cliff, 
        uint256 _duration, 
        uint256 _slicePeriodSeconds, 
        bool _revocable
    ) public virtual {
        require(hasRole(MANAGER_ROLE, _msgSender()), "unauthorized");
        createVestingSchedule(_recipient, _start, _cliff, _duration, _slicePeriodSeconds, _revocable, _amount);
        super.transfer(_recipient, _amount);
    }

    function vestedBatchTransfer(
        address[] calldata _recipients, 
        uint256[] calldata _amounts, 
        uint256 _start, 
        uint256 _cliff, 
        uint256 _duration, 
        uint256 _slicePeriodSeconds, 
        bool _revocable
    ) public virtual {
        require(hasRole(MANAGER_ROLE, _msgSender()), "unauthorized");
        require(_recipients.length == _amounts.length, "address & amount size mismatch");
        require(_duration > 0, "duration must be > 0");
        require(_cliff <= _duration, "invalid cliff");
        require(_slicePeriodSeconds >= 1, "slicePeriodSeconds must be >= 1");
        uint256 cliff = _start.add(_cliff);

        for (uint i; i < _recipients.length; i++) {
            require(_amounts[i] > 0, "amount must be > 0");
            bytes32 vestingScheduleId = this.computeNextVestingScheduleIdForHolder(_recipients[i]);
            vestingSchedules[vestingScheduleId] = VestingSchedule(
                true,
                _recipients[i],
                cliff,
                _start,
                _duration,
                _slicePeriodSeconds,
                _revocable,
                _amounts[i],
                0,
                false
            );
            vestingSchedulesTotalAmount = vestingSchedulesTotalAmount.add(_amounts[i]);
            vestingSchedulesIds.push(vestingScheduleId);
            uint256 currentVestingCount = holdersVestingCount[_recipients[i]];
            holdersVestingCount[_recipients[i]] = currentVestingCount.add(1);

            emit VestingCreated(vestingScheduleId, _recipients[i], _amounts[i]);
            super.transfer(_recipients[i], _amounts[i]);
        }
    }

    /**
     *  @notice          Lets an authorized address mint tokens to a recipient.
     *  @dev             The logic in the `_canMint` function determines whether the caller is authorized to mint tokens.
     *
     *  @param _to       The recipient of the tokens to mint.
     *  @param _amount   Quantity of tokens to mint.
     */
    function mintTo(address _to, uint256 _amount) public override {
        require(!_mintLocked, "Minting stopped");

        super.mintTo(_to, _amount);
    }
}