// SPDX-License-Identifier: UNLICENSED

// File: contracts/abstract/OwnableDelegateProxy.sol


pragma solidity 0.8.9;

contract OwnableDelegateProxy {}
// File: contracts/abstract/ProxyRegistry.sol


pragma solidity 0.8.9;


// Part: ProxyRegistry

contract ProxyRegistry {
    mapping(address => OwnableDelegateProxy) public proxies;
}

// File: contracts/abstract/IERC1155TokenReceiver.sol


pragma solidity 0.8.9;

/**
 * @dev ERC-1155 interface for accepting safe transfers.
 */
interface IERC1155TokenReceiver {

    /**
     * @notice Handle the receipt of a single ERC1155 token type
     * @dev An ERC1155-compliant smart contract MUST call this function on the token recipient contract, at the end of a `safeTransferFrom` after the balance has been updated
     * This function MAY throw to revert and reject the transfer
     * Return of other amount than the magic value MUST result in the transaction being reverted
     * Note: The token contract address is always the message sender
     * @param _operator  The address which called the `safeTransferFrom` function
     * @param _from      The address which previously owned the token
     * @param _id        The id of the token being transferred
     * @param _amount    The amount of tokens being transferred
     * @param _data      Additional data with no specified format
     * @return           `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`
     */
    function onERC1155Received(
        address _operator,
        address _from,
        uint256 _id,
        uint256 _amount,
        bytes calldata _data
    )
        external returns (
            bytes4
        )
    ;

    /**
     * @notice Handle the receipt of multiple ERC1155 token types
     * @dev An ERC1155-compliant smart contract MUST call this function on the token recipient contract, at the end of a `safeBatchTransferFrom` after the balances have been updated
     * This function MAY throw to revert and reject the transfer
     * Return of other amount than the magic value WILL result in the transaction being reverted
     * Note: The token contract address is always the message sender
     * @param _operator  The address which called the `safeBatchTransferFrom` function
     * @param _from      The address which previously owned the token
     * @param _ids       An array containing ids of each token being transferred
     * @param _amounts   An array containing amounts of each token being transferred
     * @param _data      Additional data with no specified format
     * @return           `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`
     */
    function onERC1155BatchReceived(
        address _operator,
        address _from,
        uint256[] calldata _ids,
        uint256[] calldata _amounts,
        bytes calldata _data
    )
        external returns (
            bytes4
        )
    ;

    /**
     * @notice Indicates whether a contract implements the `ERC1155TokenReceiver` functions and so can accept ERC1155 token types.
     * @param  interfaceID The ERC-165 interface ID that is queried for support.s
     * @dev This function MUST return true if it implements the ERC1155TokenReceiver interface and ERC-165 interface.
     *      This function MUST NOT consume more than 5,000 gas.
     * @return Wheter ERC-165 or ERC1155TokenReceiver interfaces are supported.
     */
    function supportsInterface(bytes4 interfaceID) external view returns (bool);
}
// File: contracts/abstract/ERC1155Metadata.sol


pragma solidity 0.8.9;

/**
 * @notice Contract that handles metadata related methods.
 * @dev Methods assume a deterministic generation of URI based on token IDs.
 *      Methods also assume that URI uses hex representation of token IDs.
 */
abstract contract ERC1155Metadata {

    /***********************************|
     *   |     Metadata Public Function s    |
     |__________________________________*/
    /**
     * @notice A distinct Uniform Resource Identifier (URI) for a given token.
     * @dev URIs are defined in RFC 3986.
     *      URIs are assumed to be deterministically generated based on token ID
     *      Token IDs are assumed to be represented in their hex format in URIs
     * @return URI string
     */
    function uri(uint256 _id) external view virtual returns (string memory);
}



// File: contracts/abstract/IERC1155.sol


pragma solidity 0.8.9;

interface IERC1155 {
    // Events
    /**
     * @dev Either TransferSingle or TransferBatch MUST emit when tokens are transferred, including zero amount transfers as well as minting or burning
     *   Operator MUST be msg.sender
     *   When minting/creating tokens, the `_from` field MUST be set to `0x0`
     *   When burning/destroying tokens, the `_to` field MUST be set to `0x0`
     *   The total amount transferred from address 0x0 minus the total amount transferred to 0x0 may be used by clients and exchanges to be added to the "circulating supply" for a given token ID
     *   To broadcast the existence of a token ID with no initial balance, the contract SHOULD emit the TransferSingle event from `0x0` to `0x0`, with the token creator as `_operator`, and a `_amount` of 0
     */
    event TransferSingle(address indexed _operator,
        address indexed _from,
        address indexed _to,
        uint256 _id,
        uint256 _amount);

    /**
     * @dev Either TransferSingle or TransferBatch MUST emit when tokens are transferred, including zero amount transfers as well as minting or burning
     *   Operator MUST be msg.sender
     *   When minting/creating tokens, the `_from` field MUST be set to `0x0`
     *   When burning/destroying tokens, the `_to` field MUST be set to `0x0`
     *   The total amount transferred from address 0x0 minus the total amount transferred to 0x0 may be used by clients and exchanges to be added to the "circulating supply" for a given token ID
     *   To broadcast the existence of multiple token IDs with no initial balance, this SHOULD emit the TransferBatch event from `0x0` to `0x0`, with the token creator as `_operator`, and a `_amount` of 0
     */
    event TransferBatch(address indexed _operator,
        address indexed _from,
        address indexed _to,
        uint256[] _ids,
        uint256[] _amounts);

    /**
     * @dev MUST emit when an approval is updated
     */
    event ApprovalForAll(address indexed _owner,
        address indexed _operator,
        bool _approved);

    /**
     * @dev MUST emit when the URI is updated for a token ID
     *   URIs are defined in RFC 3986
     *   The URI MUST point a JSON file that conforms to the "ERC-1155 Metadata JSON Schema"
     */
    event URI(string _uri, uint256 indexed _id);

    /**
     * @notice Transfers amount of an _id from the _from address to the _to address specified
     * @dev MUST emit TransferSingle event on success
     * Caller must be approved to manage the _from account's tokens (see isApprovedForAll)
     * MUST throw if `_to` is the zero address
     * MUST throw if balance of sender for token `_id` is lower than the `_amount` sent
     * MUST throw on any other error
     * When transfer is complete, this function MUST check if `_to` is a smart contract (code size > 0). If so, it MUST call `onERC1155Received` on `_to` and revert if the return amount is not `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`
     * @param _from    Source address
     * @param _to      Target address
     * @param _id      ID of the token type
     * @param _amount  Transfered amount
     * @param _data    Additional data with no specified format, sent in call to `_to`
     */
    function safeTransferFrom(
        address _from,
        address _to,
        uint256 _id,
        uint256 _amount,
        bytes calldata _data
    )
        external;

    /**
     * @notice Send multiple types of Tokens from the _from address to the _to address (with safety call)
     * @dev MUST emit TransferBatch event on success
     * Caller must be approved to manage the _from account's tokens (see isApprovedForAll)
     * MUST throw if `_to` is the zero address
     * MUST throw if length of `_ids` is not the same as length of `_amounts`
     * MUST throw if any of the balance of sender for token `_ids` is lower than the respective `_amounts` sent
     * MUST throw on any other error
     * When transfer is complete, this function MUST check if `_to` is a smart contract (code size > 0). If so, it MUST call `onERC1155BatchReceived` on `_to` and revert if the return amount is not `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`
     * Transfers and events MUST occur in the array order they were submitted (_ids[0] before _ids[1], etc)
     * @param _from     Source addresses
     * @param _to       Target addresses
     * @param _ids      IDs of each token type
     * @param _amounts  Transfer amounts per token type
     * @param _data     Additional data with no specified format, sent in call to `_to`
     */
    function safeBatchTransferFrom(
        address _from,
        address _to,
        uint256[] calldata _ids,
        uint256[] calldata _amounts,
        bytes calldata _data
    )
        external;

    /**
     * @notice Get the balance of an account's Tokens
     * @param _owner  The address of the token holder
     * @param _id     ID of the Token
     * @return        The _owner's balance of the Token type requested
     */
    function balanceOf(address _owner, uint256 _id) external view
        returns (uint256);

    /**
     * @notice Get the balance of multiple account/token pairs
     * @param _owners The addresses of the token holders
     * @param _ids    ID of the Tokens
     * @return        The _owner's balance of the Token types requested (i.e. balance for each (owner, id) pair)
     */
    function balanceOfBatch(
        address[] calldata _owners,
        uint256[] calldata _ids
    )
        external
        view
        returns (
            uint256[] memory
        )
    ;

    /**
     * @notice Enable or disable approval for a third party ("operator") to manage all of caller's tokens
     * @dev MUST emit the ApprovalForAll event on success
     * @param _operator  Address to add to the set of authorized operators
     * @param _approved  True if the operator is approved, false to revoke approval
     */
    function setApprovalForAll(address _operator, bool _approved) external;

    /**
     * @notice Queries the approval status of an operator for a given owner
     * @param _owner      The owner of the Tokens
     * @param _operator   Address of authorized operator
     * @return isOperator True if the operator is approved, false if not
     */
    function isApprovedForAll(
        address _owner,
        address _operator
    )
        external
        view
        returns (
            bool isOperator
        )
    ;
}

// File: contracts/abstract/IERC165.sol


pragma solidity 0.8.9;

/**
 * @title ERC165
 * @dev https://github.com/ethereum/EIPs/blob/master/EIPS/eip-165.md
 */
interface IERC165 {

    /**
     * @notice Query if a contract implements an interface
     * @dev Interface identification is specified in ERC-165. This function
     * uses less than 30,000 gas
     * @param _interfaceId The interface identifier, as specified in ERC-165
     */
    function supportsInterface(bytes4 _interfaceId) external view
        returns (bool);
}
// File: contracts/abstract/Address.sol


pragma solidity 0.8.9;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(
            address(this).balance >= amount,
            "Address: insufficient balance"
        );

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{value: amount}("");
        require(
            success,
            "Address: unable to send value, recipient may have reverted"
        );
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data)
        internal
        returns (bytes memory)
    {
        return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return
            functionCallWithValue(
                target,
                data,
                value,
                "Address: low-level call with value failed"
            );
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(
            address(this).balance >= value,
            "Address: insufficient balance for call"
        );
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{value: value}(
            data
        );
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data)
        internal
        view
        returns (bytes memory)
    {
        return
            functionStaticCall(
                target,
                data,
                "Address: low-level static call failed"
            );
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.3._
     */
    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 v3.3._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) private pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}



// File: contracts/abstract/Roles.sol


pragma solidity 0.8.9;

/**
 * @title Roles
 * @dev Library for managing addresses assigned to a Role.
 */
library Roles {

    struct Role {
        mapping(address => bool) bearer;
    }

    /**
     * @dev Give an account access to this role.
     */
    function add(Role storage role, address account) internal {
        require(!has(role, account), "Roles: account already has role");
        role.bearer[account] = true;
    }

    /**
     * @dev Remove an account's access to this role.
     */
    function remove(Role storage role, address account) internal {
        require(has(role, account), "Roles: account does not have role");
        role.bearer[account] = false;
    }

    /**
     * @dev Check if an account has this role.
     * @return bool
     */
    function has(Role storage role, address account) internal view
        returns (bool) {
        require(account != address(0), "Roles: account is the zero address");
        return role.bearer[account];
    }
}



// File: contracts/abstract/Context.sol


pragma solidity 0.8.9;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 * 
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}



// File: contracts/abstract/Ownable.sol


pragma solidity 0.8.9;


// Part: OpenZeppelin/openzeppelin-contracts@2.5.1/Ownable

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(isOwner(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Returns true if the caller is the current owner.
     */
    function isOwner() public view returns (bool) {
        return _msgSender() == _owner;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public onlyOwner {
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     */
    function _transferOwnership(address newOwner) internal {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

// File: contracts/abstract/MinterRole.sol


pragma solidity 0.8.9;




/**
 * @title MinterRole
 * @dev Owner is responsible to add/remove minter
 */
contract MinterRole is Context, Ownable {

    using Roles for Roles.Role;

    event MinterAdded(address indexed account);

    event MinterRemoved(address indexed account);

    Roles.Role private _minters;

    modifier onlyMinter() {
        require(
            isMinter(_msgSender()),
            "MinterRole: caller does not have the Minter role"
        );
        _;
    }

    function isMinter(address account) public view returns (bool) {
        return _minters.has(account);
    }

    function addMinter(address account) public onlyOwner {
        _addMinter(account);
    }

    function renounceMinter() public {
        _removeMinter(_msgSender());
    }

    function _addMinter(address account) internal {
        _minters.add(account);
        emit MinterAdded(account);
    }

    function _removeMinter(address account) internal {
        _minters.remove(account);
        emit MinterRemoved(account);
    }
}

// File: contracts/abstract/SafeMath.sol


pragma solidity 0.8.9;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 * 
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 * 
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     * 
     * Counterpart to Solidity's `+` operator.
     * 
     * Requirements:
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     * 
     * Counterpart to Solidity's `-` operator.
     * 
     * Requirements:
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     * 
     * Counterpart to Solidity's `-` operator.
     * 
     * Requirements:
     * - Subtraction cannot overflow.
     * 
     * _Available since v2.4.0._
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @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) {
        // 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 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts on
     * division by zero. The result is rounded towards zero.
     * 
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     * 
     * Requirements:
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts 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.
     * 
     * _Available since v2.4.0._
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts 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 mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message 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.
     * 
     * _Available since v2.4.0._
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}



// File: contracts/abstract/ERC1155.sol


pragma solidity 0.8.9;







/**
 * @dev Implementation of Multi-Token Standard contract
 */
abstract contract ERC1155 is IERC1155, IERC165, ERC1155Metadata {
    using SafeMath for uint256;
    using Address for address;

    /***********************************|
     *   |        Variables and Events       |
     |__________________________________*/
    // onReceive function signatures
    bytes4 internal constant ERC1155_RECEIVED_VALUE = 0xf23a6e61;
    bytes4 internal constant ERC1155_BATCH_RECEIVED_VALUE = 0xbc197c81;

    // Objects balances
    mapping(address => mapping(uint256 => uint256)) internal balances;

    // Operator Functions
    mapping(address => mapping(address => bool)) internal operators;

    /***********************************|
     *   |     Public Transfer Functions     |
     |__________________________________*/
    /**
     * @notice Transfers amount amount of an _id from the _from address to the _to address specified
     * @param _from    Source address
     * @param _to      Target address
     * @param _id      ID of the token type
     * @param _amount  Transfered amount
     * @param _data    Additional data with no specified format, sent in call to `_to`
     */
    function safeTransferFrom(
        address _from,
        address _to,
        uint256 _id,
        uint256 _amount,
        bytes memory _data
    )
        public override virtual {
        require((
                msg.sender == _from
                )
            || _isApprovedForAll(_from, msg.sender), "ERC1155#safeTransferFrom: INVALID_OPERATOR");
        require(_to != address(0), "ERC1155#safeTransferFrom: INVALID_RECIPIENT");
        // require(_amount >= balances[_from][_id]) is not necessary since checked with safemath operations
        _safeTransferFrom(_from, _to, _id, _amount);
        _callonERC1155Received(_from, _to, _id, _amount, _data);
    }

    /**
     * @notice Send multiple types of Tokens from the _from address to the _to address (with safety call)
     * @param _from     Source addresses
     * @param _to       Target addresses
     * @param _ids      IDs of each token type
     * @param _amounts  Transfer amounts per token type
     * @param _data     Additional data with no specified format, sent in call to `_to`
     */
    function safeBatchTransferFrom(
        address _from,
        address _to,
        uint256[] memory _ids,
        uint256[] memory _amounts,
        bytes memory _data
    )
        public override virtual {
        // Requirements
        require((
                msg.sender == _from
                )
            || _isApprovedForAll(_from, msg.sender), "ERC1155#safeBatchTransferFrom: INVALID_OPERATOR");
        require(_to != address(0), "ERC1155#safeBatchTransferFrom: INVALID_RECIPIENT");

        _safeBatchTransferFrom(_from, _to, _ids, _amounts);
        _callonERC1155BatchReceived(_from, _to, _ids, _amounts, _data);
    }

    /***********************************|
     *   |    Internal Transfer Functions    |
     |__________________________________*/
    /**
     * @dev Transfers amount amount of an _id from the _from address to the _to address specified
     * @param _from    Source address
     * @param _to      Target address
     * @param _id      ID of the token type
     * @param _amount  Transfered amount
     */
    function _safeTransferFrom(
        address _from,
        address _to,
        uint256 _id,
        uint256 _amount
    )
        internal {
        // Update balances
        balances[_from][_id] = balances[_from][_id].sub (
            _amount
            )
        ; // Subtract amount
        balances[_to][_id] = balances[_to][_id].add(_amount); // Add amount
        // Emit event
        emit TransferSingle(msg.sender, _from, _to, _id, _amount);
    }

    /**
     * @dev Verifies if receiver is contract and if so, calls (_to).onERC1155Received(...)
     */
    function _callonERC1155Received(
        address _from,
        address _to,
        uint256 _id,
        uint256 _amount,
        bytes memory _data
    )
        internal {
        if (_to.isContract()) {
            try IERC1155TokenReceiver(_to).onERC1155Received(msg.sender, _from, _id, _amount, _data) returns (bytes4 response) {
                if (response != ERC1155_RECEIVED_VALUE) {
                    revert("ERC1155#_callonERC1155Received: INVALID_ON_RECEIVE_MESSAGE");
                }
            } catch Error(string memory reason) {
                revert(reason);
            } catch {
                revert("ERC1155#_callonERC1155Received: transfer to non ERC1155Receiver implementer");
            }
        }
    }

    /**
     * @dev Send multiple types of Tokens from the _from address to the _to address (with safety call)
     * @param _from     Source addresses
     * @param _to       Target addresses
     * @param _ids      IDs of each token type
     * @param _amounts  Transfer amounts per token type
     */
    function _safeBatchTransferFrom(
        address _from,
        address _to,
        uint256[] memory _ids,
        uint256[] memory _amounts
    )
        internal {
        require (
            _ids.length == _amounts.length, "ERC1155#_safeBatchTransferFrom: INVALID_ARRAYS_LENGTH"
            )
        ;

        // Number of transfer to execute
        uint256 nTransfer = _ids.length;

        // Executing all transfers
        for (uint256 i = 0; i < nTransfer;i++) {
            // Update storage balance of previous bin
            balances[_from][_ids[i]] = balances[_from][_ids[i]].sub(_amounts[i]);
            balances[_to][_ids[i]] = balances[_to][_ids[i]].add(_amounts[i]);
        }

        // Emit event
        emit TransferBatch(msg.sender, _from, _to, _ids, _amounts);
    }

    /**
     * @dev Verifies if receiver is contract and if so, calls (_to).onERC1155BatchReceived(...)
     */
    function _callonERC1155BatchReceived(
        address _from,
        address _to,
        uint256[] memory _ids,
        uint256[] memory _amounts,
        bytes memory _data
    )
        internal {
        // Check if recipient is contract
        if (_to.isContract()
        ) {
            try IERC1155TokenReceiver(_to).onERC1155BatchReceived(msg.sender, _from, _ids, _amounts, _data) returns (bytes4 response) {
                if (response != ERC1155_BATCH_RECEIVED_VALUE) {
                    revert("ERC1155#_callonERC1155BatchReceived: INVALID_ON_RECEIVE_MESSAGE");
                }
            } catch Error(string memory reason) {
                revert(reason);
            } catch {
                revert("ERC1155#_callonERC1155BatchReceived: transfer to non ERC1155Receiver implementer");
            }
        }
    }

    /**
     * @notice Enable or disable approval for a third party ("operator") to manage all of caller's tokens
     * @param _operator  Address to add to the set of authorized operators
     * @param _approved  True if the operator is approved, false to revoke approval
     */
    function setApprovalForAll(address _operator, bool _approved) external override {
        // Update operator status
        operators[msg.sender][_operator] = _approved;
        emit ApprovalForAll(msg.sender, _operator, _approved);
    }

    /**
     * @dev Queries the approval status of an operator for a given owner
     * @param _owner      The owner of the Tokens
     * @param _operator   Address of authorized operator
     * @return isOperator true if the operator is approved, false if not
     */
    function _isApprovedForAll(
        address _owner,
        address _operator
    )
        internal
        view
        returns (bool isOperator) {
        return operators[_owner][_operator];
    }

    /**
     * @notice Get the balance of an account's Tokens
     * @param _owner  The address of the token holder
     * @param _id     ID of the Token
     * @return The _owner's balance of the Token type requested
     */
    function balanceOf(address _owner, uint256 _id) override public view returns (uint256) {
        return balances[_owner][_id];
    }

    /**
     * @notice Get the balance of multiple account/token pairs
     * @param _owners The addresses of the token holders
     * @param _ids    ID of the Tokens
     * @return        The _owner's balance of the Token types requested (i.e. balance for each (owner, id) pair)
     */
    function balanceOfBatch(address[] memory _owners, uint256[] memory _ids)
        override
        public
        view
        returns (uint256[] memory) {
        require(_owners.length == _ids.length, "ERC1155#balanceOfBatch: INVALID_ARRAY_LENGTH");

        // Variables
        uint256[] memory batchBalances = new uint256[](_owners.length);

        // Iterate over each owner and token ID
        for (uint256 i = 0; i < _owners.length;i++) {
            batchBalances[i] = balances[_owners[i]][_ids[i]];
        }

        return batchBalances;
    }

    /*
     * INTERFACE_SIGNATURE_ERC165 = bytes4(keccak256("supportsInterface(bytes4)"));
     */
    bytes4 private constant INTERFACE_SIGNATURE_ERC165 = 0x01ffc9a7;

    /*
     * INTERFACE_SIGNATURE_ERC1155 =
     * bytes4(keccak256("safeTransferFrom(address,address,uint256,uint256,bytes)")) ^
     * bytes4(keccak256("safeBatchTransferFrom(address,address,uint256[],uint256[],bytes)")) ^
     * bytes4(keccak256("balanceOf(address,uint256)")) ^
     * bytes4(keccak256("balanceOfBatch(address[],uint256[])")) ^
     * bytes4(keccak256("setApprovalForAll(address,bool)")) ^
     * bytes4(keccak256("isApprovedForAll(address,address)"));
     */
    bytes4 private constant INTERFACE_SIGNATURE_ERC1155 = 0xd9b67a26;

    /**
     * @notice Query if a contract implements an interface
     * @param _interfaceID  The interface identifier, as specified in ERC-165
     * @return `true` if the contract implements `_interfaceID` and
     */
    function supportsInterface(bytes4 _interfaceID) override external pure returns (bool) {
        if (_interfaceID == INTERFACE_SIGNATURE_ERC165 || _interfaceID == INTERFACE_SIGNATURE_ERC1155) {
            return true;
        }
        return false;
    }
}



// File: contracts/abstract/ERC1155MintBurn.sol


pragma solidity 0.8.9;



/**
 * @dev Multi-Fungible Tokens with minting and burning methods. These methods assume
 *      a parent contract to be executed as they are `internal` functions
 */
abstract contract ERC1155MintBurn is ERC1155 {
    using SafeMath for uint256;

    /****************************************|
     *   |            Minting Functions           |
     |_______________________________________*/
    /**
     * @dev Mint _amount of tokens of a given id
     * @param _to      The address to mint tokens to
     * @param _id      Token id to mint
     * @param _amount  The amount to be minted
     * @param _data    Data to pass if receiver is contract
     */
    function _mint(address _to, uint256 _id, uint256 _amount, bytes memory _data) internal {
        // Add _amount
        balances[_to][_id] = balances[_to][_id].add(_amount);

        // Emit event
        emit TransferSingle(msg.sender, address(0x0), _to, _id, _amount);

        // Calling onReceive method if recipient is contract
        _callonERC1155Received(address(0x0), _to, _id, _amount, _data);
    }

    /**
     * @dev Mint tokens for each ids in _ids
     * @param _to       The address to mint tokens to
     * @param _ids      Array of ids to mint
     * @param _amounts  Array of amount of tokens to mint per id
     * @param _data    Data to pass if receiver is contract
     */
    function _batchMint(
        address _to,
        uint256[] memory _ids,
        uint256[] memory _amounts,
        bytes memory _data
    )
        internal {
        require (
            _ids.length == _amounts.length, "ERC1155MintBurn#batchMint: INVALID_ARRAYS_LENGTH"
            )
        ;

        // Number of mints to execute
        uint256 nMint = _ids.length;

        // Executing all minting
        for (uint256 i = 0; i < nMint;i++) {
            // Update storage balance
            balances[_to][_ids[i]] = balances[_to][_ids[i]].add(_amounts[i]);
        }

        // Emit batch mint event
        emit TransferBatch(msg.sender, address(0x0), _to, _ids, _amounts);

        // Calling onReceive method if recipient is contract
        _callonERC1155BatchReceived(address(0x0), _to, _ids, _amounts, _data);
    }

    /****************************************|
     *   |            Burning Functions           |
     |_______________________________________*/
    /**
     * @dev Burn _amount of tokens of a given token id
     * @param _from    The address to burn tokens from
     * @param _id      Token id to burn
     * @param _amount  The amount to be burned
     */
    function _burn(address _from, uint256 _id,
        uint256 _amount) internal {
        // Substract _amount
        balances[_from][_id] = balances[_from][_id].sub(_amount);

        // Emit event
        emit TransferSingle(msg.sender, _from, address(0x0), _id, _amount);
    }

    /**
     * @dev Burn tokens of given token id for each (_ids[i], _amounts[i]) pair
     * @param _from     The address to burn tokens from
     * @param _ids      Array of token ids to burn
     * @param _amounts  Array of the amount to be burned
     */
    function _batchBurn(
        address _from,
        uint256[] memory _ids,
        uint256[] memory _amounts
    )
        internal {
        require (
            _ids.length == _amounts.length, "ERC1155MintBurn#batchBurn: INVALID_ARRAYS_LENGTH"
            )
        ;

        // Number of mints to execute
        uint256 nBurn = _ids.length;

        // Executing all minting
        for (uint256 i = 0; i < nBurn;i++) {
            // Update storage balance
            balances[_from][_ids[i]] = balances[_from][_ids[i]].sub(_amounts[i]);
        }

        // Emit batch mint event
        emit TransferBatch(msg.sender, _from, address(0x0), _ids, _amounts);
    }
}



// File: contracts/abstract/ERC1155Tradable.sol


pragma solidity 0.8.9;








/**
 * @title ERC1155Tradable
 * ERC1155Tradable - ERC1155 contract that whitelists an operator address, 
 * has create and mint functionality, and supports useful standards from OpenZeppelin,
 *   like _exists(), name(), symbol(), and totalSupply()
 */
abstract contract ERC1155Tradable is ERC1155MintBurn, Ownable, MinterRole {
    using SafeMath for uint256;
    using Address for address;

    // OpenSea proxy registry to ease selling NFTs on OpenSea
    address public proxyRegistryAddress;

    mapping(uint256 => address) public creators;
    mapping(uint256 => uint256) public tokenSupply;
    mapping(uint256 => uint256) public tokenMaxSupply;
    mapping(uint256 => uint8) public tokenCityIndex;
    mapping(uint256 => uint8) public tokenType;

    // Contract name
    string public name;

    // Contract symbol
    string public symbol;

    // URI's default URI prefix
    string internal baseMetadataURI;

    uint256 internal _currentTokenID = 0;

    constructor (string memory _name, string memory _symbol, address _proxyRegistryAddress, string memory _baseMetadataURI) {
        name = _name;
        symbol = _symbol;
        proxyRegistryAddress = _proxyRegistryAddress;
        baseMetadataURI = _baseMetadataURI;
    }

    function contractURI() public view returns (string memory) {
        return string(abi.encodePacked(baseMetadataURI));
    }

    /**
     * @dev Returns URIs are defined in RFC 3986.
     *      URIs are assumed to be deterministically generated based on token ID
     *      Token IDs are assumed to be represented in their hex format in URIs
     * @return URI string
     */
    function uri(uint256 _id) override external view returns (string memory) {
        require(_exists(_id), "Deed NFT doesn't exists");
        return string(abi.encodePacked(baseMetadataURI, _uint2str(_id)));
    }

    /**
     * @dev Returns the total quantity for a token ID
     * @param _id uint256 ID of the token to query
     * @return amount of token in existence
     */
    function totalSupply(uint256 _id) public view returns (uint256) {
        return tokenSupply[_id];
    }

    /**
     * @dev Returns the max quantity for a token ID
     * @param _id uint256 ID of the token to query
     * @return amount of token in existence
     */
    function maxSupply(uint256 _id) public view returns (uint256) {
        return tokenMaxSupply[_id];
    }

    /**
     * @dev return city index of designated NFT with its identifier
     */
    function cityIndex(uint256 _id) public view returns (uint256) {
        require(_exists(_id), "Deed NFT doesn't exists");
        return tokenCityIndex[_id];
    }

    /**
     * @dev return card type of designated NFT with its identifier
     */
    function cardType(uint256 _id) public view returns (uint256) {
        require(_exists(_id), "Deed NFT doesn't exists");
        return tokenType[_id];
    }

    /**
     * @dev Creates a new token type and assigns _initialSupply to an address
     * @param _initialOwner the first owner of the Token
     * @param _initialSupply Optional amount to supply the first owner (1 for NFT)
     * @param _maxSupply max supply allowed (1 for NFT)
     * @param _cityIndex city index of NFT
     *    (0 = Tanit, 1 = Reshef, 2 = Ashtarte, 3 = Melqart, 4 = Eshmun, 5 = Kushor, 6 = Hammon)
     * @param _type card type of NFT
     *    (0 = Common, 1 = Uncommon, 2 = Rare, 3 = Legendary)
     * @param _data Optional data to pass if receiver is contract
     * @return The newly created token ID
     */
    function create(
        address _initialOwner,
        uint256 _initialSupply,
        uint256 _maxSupply,
        uint8 _cityIndex,
        uint8 _type,
        bytes memory _data
    ) public onlyMinter returns (uint256) {
        require(_initialSupply <= _maxSupply, "_initialSupply > _maxSupply");
        uint256 _id = _getNextTokenID();
        _incrementTokenTypeId();
        creators[_id] = _initialOwner;

        if (_initialSupply != 0) {
            _mint(_initialOwner, _id, _initialSupply, _data);
        }
        tokenSupply[_id] = _initialSupply;
        tokenMaxSupply[_id] = _maxSupply;
        tokenCityIndex[_id] = _cityIndex;
        tokenType[_id] = _type;
        return _id;
    }

    /**
     * @dev Override isApprovedForAll to whitelist user's OpenSea proxy accounts to enable gas-free listings.
     * @param _owner      The owner of the Tokens
     * @param _operator   Address of authorized operator
     * @return isOperator true if the operator is approved, false if not
     */
    function isApprovedForAll(address _owner, address _operator) override public view returns (bool isOperator) {
        // Whitelist OpenSea proxy contract for easy trading.
        ProxyRegistry proxyRegistry = ProxyRegistry(proxyRegistryAddress);
        if (address(proxyRegistry.proxies(_owner)) == _operator) {
            return true;
        }

        return _isApprovedForAll(_owner, _operator);
    }

    /**
     * @dev Returns whether the specified token exists by checking to see if it has a creator
     * @param _id uint256 ID of the token to query the existence of
     * @return bool whether the token exists
     */
    function _exists(uint256 _id) internal view returns (bool) {
        return creators[_id] != address(0);
    }

    /**
     * @dev calculates the next token ID based on value of _currentTokenID
     * @return uint256 for the next token ID
     */
    function _getNextTokenID() private view returns (uint256) {
        return _currentTokenID.add(1);
    }

    /**
     * @dev increments the value of _currentTokenID
     */
    function _incrementTokenTypeId() private {
        _currentTokenID++;
    }

    /**
     * @dev Convert uint256 to string
     * @param _i Unsigned integer to convert to string
     */
    function _uint2str(uint _i) internal pure returns (string memory _uintAsString) {
        if (_i == 0) {
            return "0";
        }
        uint j = _i;
        uint len;
        while (j != 0) {
            len++;
            j /= 10;
        }
        bytes memory bstr = new bytes(len);
        uint k = len - 1;
        while (_i != 0) {
            bstr[k] = bytes1(uint8(48 + _i % 10));
            _i /= 10;
            if (k > 0) {
                k--;
            }
        }
        return string(bstr);
    }

}
// File: contracts/abstract/ManagerRole.sol


pragma solidity 0.8.9;





/**
 * @title ManagerRole
 * @dev Owner is responsible to add/remove manager
 */
contract ManagerRole is Context, Ownable {
    using Roles for Roles.Role;

    event ManagerAdded(address indexed account);
    event ManagerRemoved(address indexed account);

    Roles.Role private _managers;

    modifier onlyManager() {
        require(isManager(_msgSender()), "ManagerRole: caller does not have the Manager role");
        _;
    }

    function isManager(address account) public view returns (bool) {
        return _managers.has(account);
    }

    function addManager(address account) public onlyOwner {
        _addManager(account);
    }

    function removeManager(address account) public onlyOwner {
        _removeManager(account);
    }

    function _addManager(address account) internal {
        _managers.add(account);
        emit ManagerAdded(account);
    }

    function _removeManager(address account) internal {
        _managers.remove(account);
        emit ManagerRemoved(account);
    }
}



// File: contracts/abstract/StrategyRole.sol


pragma solidity 0.8.9;





/**
 * @title StrategyRole
 * @dev Owner is responsible to add/remove strategy
 */
contract StrategyRole is Context, ManagerRole {
    using Roles for Roles.Role;

    event StrategyAdded(address indexed account);
    event StrategyRemoved(address indexed account);

    Roles.Role private _strategies;

    modifier onlyStrategy() {
        require(isStrategy(_msgSender()), "StrategyRole: caller does not have the Strategy role");
        _;
    }

    function isStrategy(address account) public view returns (bool) {
        return _strategies.has(account);
    }

    function addStrategy(address account) public onlyManager {
        _addStrategy(account);
    }

    function removeStrategy(address account) public onlyManager {
        _removeStrategy(account);
    }

    function _addStrategy(address account) internal {
        _strategies.add(account);
        emit StrategyAdded(account);
    }

    function _removeStrategy(address account) internal {
        _strategies.remove(account);
        emit StrategyRemoved(account);
    }
}



// File: contracts/abstract/StrategyHandler.sol


pragma solidity 0.8.9;




/**
 * @title NFT Contract for Meeds DAO
 */
interface StrategyHandler is IERC1155 {

    /**
     * @dev return the total use count of an NFT by a wallet
     */
    function getTotalUseCount(address _account, uint256 _id) external view returns (uint256);

    /**
     * @dev return the use count of an NFT by wallet inside a strategy
     */
    function getStrategyUseCount(address _account, uint256 _id, address _strategy) external view returns (uint256);

    /**
     * @notice Mark NFT as being used. Only callable by registered strategies
     * @param _account  User account address
     * @param _id       ID of the token type
     */
    function startUsingNFT(address _account, uint256 _id) external returns (bool);

    /**
     * @notice Unmark NFT as being used. Only callable by registered strategies
     * @param _account  User account address
     * @param _id       ID of the token type
     */
    function endUsingNFT(address _account, uint256 _id) external returns (bool);

}

// File: contracts/Deed.sol


pragma solidity 0.8.9;







/**
 * @title NFT Contract for Meeds DAO
 */
contract Deed is ERC1155Tradable, StrategyHandler, StrategyRole {

    using SafeMath for uint256;

    event StartedUsingNFT(address indexed account,
        uint256 indexed id,
        address indexed strategy);
    event EndedUsingNFT(address indexed account,
        uint256 indexed id,
        address indexed strategy);

    // mapping account => nftId => useCount
    // this is used to restrict transfers if nft is being used in any strategy
    mapping(address => mapping(uint256 => uint256)) internal totalUseCount;

    // mapping account => nftId => strategyAddress => useCount
    // this is used to make sure a strategy can only end using nft that it started using before
    mapping(address => mapping(uint256 => mapping(address => uint256)))
        internal stratUseCount;

    constructor (address _proxyRegistryAddress, string memory _baseMetadataURI) ERC1155Tradable("Meeds Deed Token", "DEED", _proxyRegistryAddress, _baseMetadataURI) {
    }

    /**
     * @dev Will update the base URL of token's URI
     * @param _newBaseMetadataURI New base URL of token's URI
     */
    function setBaseMetadataURI(string memory _newBaseMetadataURI) public onlyManager {
        baseMetadataURI = _newBaseMetadataURI;
    }

    /**
     * @dev return the list of NFTs owned by an address
     */
    function nftsOf(address _account) public view returns (uint256[] memory) {
        uint256 len = 0;
        for (uint256 i = 1; i <= _currentTokenID; i++) {
            if (balances[_account][i] > 0) {
              len++;
            }
        }
        uint256 index = 0;
        uint256[] memory nfts = new uint256[](len);
        for (uint256 i = 1; i <= _currentTokenID; i++) {
            if (balances[_account][i] > 0) {
              nfts[index++] = i;
            }
        }
        return nfts;
    }

    /**
     * @dev return the total supply of NFTs (Token Types)
     */
    function totalSupply() public view returns (uint256) {
        return _currentTokenID;
    }

    /**
     * @dev return the total use count of an NFT by owner
     */
    function getTotalUseCount(address _account, uint256 _id) external view returns (uint256) {
        return totalUseCount[_account][_id];
    }

    /**
     * @dev return the use count of an NFT by wallet inside a strategy
     */
    function getStrategyUseCount(address _account, uint256 _id, address _strategy) external view returns (uint256) {
        return stratUseCount[_account][_id][_strategy];
    }

    /**
     * @notice Mark NFT as being used. Only callable by registered strategies
     * @param _account  User account address
     * @param _id       ID of the token type
     */
    function startUsingNFT(address _account, uint256 _id) external onlyStrategy returns (bool) {
        require(balances[_account][_id] > 0, "Deed#startUsingNFT: user account doesn't own the NFT");
        stratUseCount[_account][_id][msg.sender] = stratUseCount[_account][_id][msg.sender].add(1);
        totalUseCount[_account][_id] = totalUseCount[_account][_id].add(1);
        emit StartedUsingNFT(_account, _id, msg.sender);
        return true;
    }

    /**
     * @notice Unmark NFT as being used. Only callable by registered strategies
     * @param _account  User account address
     * @param _id       ID of the token type
     */
    function endUsingNFT(address _account, uint256 _id) external onlyStrategy returns (bool) {
        require(stratUseCount[_account][_id][msg.sender] > 0, "Deed#endUsingNFT: NFT is not currently in use by strategy");
        stratUseCount[_account][_id][msg.sender] = stratUseCount[_account][_id][msg.sender].sub(1);
        totalUseCount[_account][_id] = totalUseCount[_account][_id].sub(1);
        emit EndedUsingNFT(_account, _id, msg.sender);
        return true;
    }

    /**
     * @dev Overrides safeTransferFrom function of ERC1155 to introduce totalUseCount check
     */
    function safeTransferFrom(address _from, address _to, uint256 _id, uint256 _amount, bytes memory _data) public override (ERC1155, IERC1155) {
        require(totalUseCount[_from][_id] == 0, "Deed#safeTransferFrom: NFT being used in strategy");
        ERC1155.safeTransferFrom(_from, _to, _id, _amount, _data);
    }

    /**
     * @dev Overrides safeBatchTransferFrom function of ERC1155 to introduce totalUseCount check
     */
    function safeBatchTransferFrom(address _from, address _to, uint256[] memory _ids, uint256[] memory _amounts, bytes memory _data) public  override (ERC1155, IERC1155) {
        // Number of transfer to execute
        uint256 nTransfer = _ids.length;

        // check if any nft is being used
        for (uint256 i = 0; i < nTransfer; i++) {
            require(totalUseCount[_from][_ids[i]] == 0, "Deed#safeBatchTransferFrom: NFT being used in strategy");
        }

        ERC1155.safeBatchTransferFrom(_from, _to, _ids, _amounts, _data);
    }

}