/**
 *Submitted for verification at Etherscan.io on 2021-12-10
*/

/**
 *Submitted for verification at Etherscan.io on 2021-11-26
*/

pragma solidity ^0.5.12;

/*
 * @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.
 */
contract Context {
    // Empty internal constructor, to prevent people from mistakenly deploying
    // an instance of this contract, which should be used via inheritance.
    constructor () internal { }
    // solhint-disable-previous-line no-empty-blocks

    function _msgSender() internal view returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

// File: openzeppelin-solidity\contracts\ownership\Ownable.sol

pragma solidity ^0.5.12;

/**
 * @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.
 */
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 () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), 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: node_modules\multi-token-standard\contracts\interfaces\IERC165.sol

pragma solidity ^0.5.12;


/**
 * @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: node_modules\multi-token-standard\contracts\utils\SafeMath.sol

pragma solidity ^0.5.12;


/**
 * @title SafeMath
 * @dev Unsigned math operations with safety checks that revert on error
 */
library SafeMath {

  /**
   * @dev Multiplies two unsigned integers, reverts on 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-solidity/pull/522
    if (a == 0) {
      return 0;
    }

    uint256 c = a * b;
    require(c / a == b, "SafeMath#mul: OVERFLOW");

    return c;
  }

  /**
   * @dev Integer division of two unsigned integers truncating the quotient, reverts on division by zero.
   */
  function div(uint256 a, uint256 b) internal pure returns (uint256) {
    // Solidity only automatically asserts when dividing by 0
    require(b > 0, "SafeMath#div: DIVISION_BY_ZERO");
    uint256 c = a / b;
    // assert(a == b * c + a % b); // There is no case in which this doesn't hold

    return c;
  }

  /**
   * @dev Subtracts two unsigned integers, reverts on overflow (i.e. if subtrahend is greater than minuend).
   */
  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
    require(b <= a, "SafeMath#sub: UNDERFLOW");
    uint256 c = a - b;

    return c;
  }

  /**
   * @dev Adds two unsigned integers, reverts on overflow.
   */
  function add(uint256 a, uint256 b) internal pure returns (uint256) {
    uint256 c = a + b;
    require(c >= a, "SafeMath#add: OVERFLOW");

    return c; 
  }

  /**
   * @dev Divides two unsigned integers and returns the remainder (unsigned integer modulo),
   * reverts when dividing by zero.
   */
  function mod(uint256 a, uint256 b) internal pure returns (uint256) {
    require(b != 0, "SafeMath#mod: DIVISION_BY_ZERO");
    return a % b;
  }

}

// File: node_modules\multi-token-standard\contracts\interfaces\IERC1155TokenReceiver.sol

pragma solidity ^0.5.12;

/**
 * @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: node_modules\multi-token-standard\contracts\interfaces\IERC1155.sol

pragma solidity ^0.5.12;


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 _amount, 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           True if the operator is approved, false if not
   */
  function isApprovedForAll(address _owner, address _operator) external view returns (bool isOperator);

}

// File: node_modules\multi-token-standard\contracts\utils\Address.sol

/**
 * Copyright 2018 ZeroEx Intl.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *   http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

pragma solidity ^0.5.12;


/**
 * Utility library of inline functions on addresses
 */
library Address {

  /**
   * Returns whether the target address is a contract
   * @dev This function will return false if invoked during the constructor of a contract,
   * as the code is not actually created until after the constructor finishes.
   * @param account address of the account to check
   * @return whether the target address is a contract
   */
  function isContract(address account) internal view returns (bool) {
    bytes32 codehash;
    bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;

    // XXX Currently there is no better way to check if there is a contract in an address
    // than to check the size of the code at that address.
    // See https://ethereum.stackexchange.com/a/14016/36603
    // for more details about how this works.
    // TODO Check this again before the Serenity release, because all addresses will be
    // contracts then.
    assembly { codehash := extcodehash(account) }
    return (codehash != 0x0 && codehash != accountHash);
  }

}

// File: multi-token-standard\contracts\tokens\ERC1155\ERC1155.sol

pragma solidity ^0.5.12;







// File: multi-token-standard\contracts\tokens\ERC1155\ERC1155Metadata.sol

pragma solidity ^0.5.12;



/**
 * @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.
 */
contract ERC1155Metadata {

  // URI's default URI prefix
  string internal baseMetadataURI;
  event URI(string _uri, uint256 indexed _id);


  /***********************************|
  |     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) public view returns (string memory) {
    return string(abi.encodePacked(baseMetadataURI, _uint2str(_id), ".json"));
  }


  /***********************************|
  |    Metadata Internal Functions    |
  |__________________________________*/

  /**
   * @notice Will emit default URI log event for corresponding token _id
   * @param _tokenIDs Array of IDs of tokens to log default URI
   */
  function _logURIs(uint256[] memory _tokenIDs) internal {
    string memory baseURL = baseMetadataURI;
    string memory tokenURI;

    for (uint256 i = 0; i < _tokenIDs.length; i++) {
      tokenURI = string(abi.encodePacked(baseURL, _uint2str(_tokenIDs[i]), ".json"));
      emit URI(tokenURI, _tokenIDs[i]);
    }
  }

  /**
   * @notice Will emit a specific URI log event for corresponding token
   * @param _tokenIDs IDs of the token corresponding to the _uris logged
   * @param _URIs    The URIs of the specified _tokenIDs
   */
  function _logURIs(uint256[] memory _tokenIDs, string[] memory _URIs) internal {
    require(_tokenIDs.length == _URIs.length, "ERC1155Metadata#_logURIs: INVALID_ARRAYS_LENGTH");
    for (uint256 i = 0; i < _tokenIDs.length; i++) {
      emit URI(_URIs[i], _tokenIDs[i]);
    }
  }

  /**
   * @notice Will update the base URL of token's URI
   * @param _newBaseMetadataURI New base URL of token's URI
   */
  function _setBaseMetadataURI(string memory _newBaseMetadataURI) internal {
    baseMetadataURI = _newBaseMetadataURI;
  }


  /***********************************|
  |    Utility Internal Functions     |
  |__________________________________*/

  /**
   * @notice Convert uint256 to string
   * @param _i Unsigned integer to convert to string
   */
  function _uint2str(uint256 _i) internal pure returns (string memory _uintAsString) {
    if (_i == 0) {
      return "0";
    }

    uint256 j = _i;
    uint256 ii = _i;
    uint256 len;

    // Get number of bytes
    while (j != 0) {
      len++;
      j /= 10;
    }

    bytes memory bstr = new bytes(len);
    uint256 k = len - 1;

    // Get each individual ASCII
    while (ii != 0) {
      bstr[k--] = byte(uint8(48 + ii % 10));
      ii /= 10;
    }

    // Convert to string
    return string(bstr);
  }

}

// File: node_modules\multi-token-standard\contracts\tokens\ERC1155\ERC1155.sol

pragma solidity ^0.5.12;







/**
 * @dev Implementation of Multi-Token Standard contract
 */
contract ERC1155 is IERC165 {
  using SafeMath for uint256;
  using Address for address;


  /***********************************|
  |        Variables and Events       |
  |__________________________________*/

  // onReceive function signatures
  bytes4 constant internal ERC1155_RECEIVED_VALUE = 0xf23a6e61;
  bytes4 constant internal ERC1155_BATCH_RECEIVED_VALUE = 0xbc197c81;

  // Objects balances
  mapping (address => mapping(uint256 => uint256)) internal balances;

  // Operator Functions
  mapping (address => mapping(address => bool)) internal operators;

  // Events
  event TransferSingle(address indexed _operator, address indexed _from, address indexed _to, uint256 _id, uint256 _amount);
  event TransferBatch(address indexed _operator, address indexed _from, address indexed _to, uint256[] _ids, uint256[] _amounts);
  event ApprovalForAll(address indexed _owner, address indexed _operator, bool _approved);
  event URI(string _uri, uint256 indexed _id);


  /***********************************|
  |     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
  {
    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
  {
    // 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    |
  |__________________________________*/

  /**
   * @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
   */
  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);
  }

  /**
   * @notice 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
  {
    // Check if recipient is contract
    if (_to.isContract()) {
      bytes4 retval = IERC1155TokenReceiver(_to).onERC1155Received(msg.sender, _from, _id, _amount, _data);
      require(retval == ERC1155_RECEIVED_VALUE, "ERC1155#_callonERC1155Received: INVALID_ON_RECEIVE_MESSAGE");
    }
  }

  /**
   * @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
   */
  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);
  }

  /**
   * @notice 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
  {
    // Pass data if recipient is contract
    if (_to.isContract()) {
      bytes4 retval = IERC1155TokenReceiver(_to).onERC1155BatchReceived(msg.sender, _from, _ids, _amounts, _data);
      require(retval == ERC1155_BATCH_RECEIVED_VALUE, "ERC1155#_callonERC1155BatchReceived: INVALID_ON_RECEIVE_MESSAGE");
    }
  }


  /***********************************|
  |         Operator Functions        |
  |__________________________________*/

  /**
   * @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
  {
    // Update operator status
    operators[msg.sender][_operator] = _approved;
    emit ApprovalForAll(msg.sender, _operator, _approved);
  }

  /**
   * @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 True if the operator is approved, false if not
   */
  function isApprovedForAll(address _owner, address _operator)
    public view returns (bool isOperator)
  {
    return operators[_owner][_operator];
  }


  /***********************************|
  |         Balance Functions         |
  |__________________________________*/

  /**
   * @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)
    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)
    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;
  }


  /***********************************|
  |          ERC165 Functions         |
  |__________________________________*/

  /**
   * INTERFACE_SIGNATURE_ERC165 = bytes4(keccak256("supportsInterface(bytes4)"));
   */
  bytes4 constant private 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 constant private 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) external view returns (bool) {
    if (_interfaceID == INTERFACE_SIGNATURE_ERC165 ||
        _interfaceID == INTERFACE_SIGNATURE_ERC1155) {
      return true;
    }
    return false;
  }

}

// File: multi-token-standard\contracts\tokens\ERC1155\ERC1155MintBurn.sol

pragma solidity ^0.5.12;



/**
 * @dev Multi-Fungible Tokens with minting and burning methods. These methods assume
 *      a parent contract to be executed as they are `internal` functions
 */
contract ERC1155MintBurn is ERC1155 {


  /****************************************|
  |            Minting Functions           |
  |_______________________________________*/

  /**
   * @notice 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);
  }

  /**
   * @notice 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           |
  |_______________________________________*/

  /**
   * @notice 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);
  }

  /**
   * @notice 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\Strings.sol

pragma solidity ^0.5.12;

library Strings {
  // via https://github.com/oraclize/ethereum-api/blob/master/oraclizeAPI_0.5.sol
  function strConcat(string memory _a, string memory _b, string memory _c, string memory _d, string memory _e) internal pure returns (string memory) {
      bytes memory _ba = bytes(_a);
      bytes memory _bb = bytes(_b);
      bytes memory _bc = bytes(_c);
      bytes memory _bd = bytes(_d);
      bytes memory _be = bytes(_e);
      string memory abcde = new string(_ba.length + _bb.length + _bc.length + _bd.length + _be.length);
      bytes memory babcde = bytes(abcde);
      uint k = 0;
      for (uint i = 0; i < _ba.length; i++) babcde[k++] = _ba[i];
      for (uint i = 0; i < _bb.length; i++) babcde[k++] = _bb[i];
      for (uint i = 0; i < _bc.length; i++) babcde[k++] = _bc[i];
      for (uint i = 0; i < _bd.length; i++) babcde[k++] = _bd[i];
      for (uint i = 0; i < _be.length; i++) babcde[k++] = _be[i];
      return string(babcde);
    }

    function strConcat(string memory _a, string memory _b, string memory _c, string memory _d) internal pure returns (string memory) {
        return strConcat(_a, _b, _c, _d, "");
    }

    function strConcat(string memory _a, string memory _b, string memory _c) internal pure returns (string memory) {
        return strConcat(_a, _b, _c, "", "");
    }

    function strConcat(string memory _a, string memory _b) internal pure returns (string memory) {
        return strConcat(_a, _b, "", "", "");
    }

    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--] = byte(uint8(48 + _i % 10));
            _i /= 10;
        }
        return string(bstr);
    }
}

// File: contracts\ERC1155Tradable.sol

pragma solidity ^0.5.12;






contract OwnableDelegateProxy { }

contract ProxyRegistry {
  mapping(address => OwnableDelegateProxy) public proxies;
}

/**
 * @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()
 */
contract ERC1155Tradable is ERC1155, ERC1155MintBurn, ERC1155Metadata, Ownable {
  using Strings for string;


  //address proxyRegistryAddress;
	uint256 private _currentTokenID = 0;
  //uint256 private _maxTokenPerUser = 1000;
  //uint256 private _maxTokenPerMint = 10;
  
  uint256 private totalTokenAssets = 6888;
	uint256 private totalReserve = 388;
  uint256 private presales1MaxToken = 500;
  uint256 private presales2MaxToken = 2888;
  
  uint256 private sold = 0;
  uint256 private reservedMinted = 0;
  uint256 private presales1Minted = 0;
  uint256 private presales2Minted = 0;

  uint256 private preSalesPrice1 = 0.15 ether;
  uint256 private preSalesPrice2 = 0.18 ether;
  uint256 private publicSalesPrice = 0.18 ether;
  address private signerAddress = 0x5704AB048DaFdD4b3793BDe9F2E5ddf657588B18;
  uint16 public salesStage = 1; //1-presales1 , 2-presales2 , 3-public
  address payable companyWallet;

  mapping(uint256 => uint256) private _presalesPrice;
  mapping(address => uint256) public presales1minted; // To check how many tokens an address has minted during presales
  mapping(address => uint256) public presales2minted; // To check how many tokens an address has minted during presales
  mapping(address => uint256) public minted; // To check how many tokens an address has minted
  mapping (uint256 => address) public creators;
  mapping (uint256 => uint256) public tokenSupply;
  // Contract name
  string public name;
  // Contract symbol
  string public symbol;

  /**
   * @dev Require msg.sender to be the creator of the token id
   */
  modifier creatorOnly(uint256 _id) {
    require(creators[_id] == msg.sender, "ERC1155Tradable#creatorOnly: ONLY_CREATOR_ALLOWED");
    _;
  }

  /**
   * @dev Require msg.sender to own more than 0 of the token id
   */
  modifier ownersOnly(uint256 _id) {
    require(balances[msg.sender][_id] > 0, "ERC1155Tradable#ownersOnly: ONLY_OWNERS_ALLOWED");
    _;
  }

  constructor(
    string memory _name,
    string memory _symbol
    //address _proxyRegistryAddress
  ) public {
    name = _name;
    symbol = _symbol;
    //proxyRegistryAddress = _proxyRegistryAddress;
  }

  function uri(
    uint256 _id
  ) public view returns (string memory) {
    require(_exists(_id), "ERC721Tradable#uri: NONEXISTENT_TOKEN");
    return Strings.strConcat(
      baseMetadataURI,
      Strings.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 Will update the base URL of token's URI
   * @param _newBaseMetadataURI New base URL of token's URI
   */
  function setBaseMetadataURI(
    string memory _newBaseMetadataURI
  ) public onlyOwner {
    _setBaseMetadataURI(_newBaseMetadataURI);
  }

  /**
    * @dev Creates a new token type and assigns _initialSupply to an address
    * NOTE: remove onlyOwner if you want third parties to create new tokens on your contract (which may change your IDs)
    * @param _initialOwner address of the first owner of the token
    * @param _initialSupply amount to supply the first owner
    * @param _uri Optional URI for this token type
    * @param _data Data to pass if receiver is contract
    * @return The newly created token ID
    */
  function reserve(
    address _initialOwner,
    uint256 _initialSupply,
    string calldata _uri,
    bytes calldata _data
  ) external onlyOwner returns (uint256) {
    require(reservedMinted + _initialSupply <= totalReserve, "Reserve Empty");

    sold += _initialSupply;
    
    for (uint256 i = 0; i < _initialSupply; i++) {
      reservedMinted++;
      uint256 _id = reservedMinted;

      if (bytes(_uri).length > 0) {
        emit URI(_uri, _id);
      }


      creators[_id] = msg.sender;
      _mint(_initialOwner, _id, 1, _data);
      tokenSupply[_id] = 1;
    }
    return 0;
  }
   
function toBytes(address a) public pure returns (bytes memory b){
    assembly {
        let m := mload(0x40)
        a := and(a, 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF)
        mstore(add(m, 20), xor(0x140000000000000000000000000000000000000000, a))
        mstore(0x40, add(m, 52))
        b := m
   }
}

function addressToString(address _addr) internal pure returns(string memory) {
    bytes32 value = bytes32(uint256(_addr));
    bytes memory alphabet = "0123456789abcdef";

    bytes memory str = new bytes(42);
    str[0] = "0";
    str[1] = "x";
    for (uint i = 0; i < 20; i++) {
        str[2+i*2] = alphabet[uint(uint8(value[i + 12] >> 4))];
        str[3+i*2] = alphabet[uint(uint8(value[i + 12] & 0x0f))];
    }
    return string(str);
}

function toAsciiString(address x) internal pure returns (string memory) {
    bytes memory s = new bytes(40);
    for (uint i = 0; i < 20; i++) {
        bytes1 b = bytes1(uint8(uint(uint160(x)) / (2**(8*(19 - i)))));
        bytes1 hi = bytes1(uint8(b) / 16);
        bytes1 lo = bytes1(uint8(b) - 16 * uint8(hi));
        s[2*i] = char(hi);
        s[2*i+1] = char(lo);            
    }
    return string(s);
}


function char(
    bytes1 b
    ) internal pure returns (bytes1 c) {
    if (uint8(b) < 10) return bytes1(uint8(b) + 0x30);
    else return bytes1(uint8(b) + 0x57);
}

function bytes32ToString(bytes32 _bytes32) public pure returns (string memory) {
    uint8 i = 0;
    bytes memory bytesArray = new bytes(64);
    for (i = 0; i < bytesArray.length; i++) {

        uint8 _f = uint8(_bytes32[i/2] & 0x0f);
        uint8 _l = uint8(_bytes32[i/2] >> 4);

        bytesArray[i] = toByte(_f);
        i = i + 1;
        bytesArray[i] = toByte(_l);
    }
    return string(bytesArray);
}

function stringToBytes32(string memory source) public pure returns (bytes32 result) {
    bytes memory tempEmptyStringTest = bytes(source);
    if (tempEmptyStringTest.length == 0) {
        return 0x0;
    }

    assembly {
        result := mload(add(source, 32))
    }
}

 function splitSignature(bytes memory sig)
       public
       pure
       returns (uint8, bytes32, bytes32)
   {
       require(sig.length == 65);

       bytes32 r;
       bytes32 s;
       uint8 v;

       assembly {
           // first 32 bytes, after the length prefix
           r := mload(add(sig, 32))
           // second 32 bytes
           s := mload(add(sig, 64))
           // final byte (first byte of the next 32 bytes)
           v := byte(0, mload(add(sig, 96)))
       }
     
       return (v, r, s);
   }

  function recoverSigner(bytes32 message, bytes memory sig)
       public
       pure
       returns (address)
    {
       uint8 v;
       bytes32 r;
       bytes32 s;

       (v, r, s) = splitSignature(sig);
       return ecrecover(message, v, r, s);
  }
  
  function isValidData(string memory _word, bytes memory sig) public view returns(bool){
    bytes32 message = keccak256(abi.encodePacked(_word));
    return (recoverSigner(message, sig) == signerAddress);
}


function toByte(uint8 _uint8) public pure returns (byte) {
    if(_uint8 < 10) {
        return byte(_uint8 + 48);
    } else {
        return byte(_uint8 + 87);
    }
}

	function withdraw() public onlyOwner {
		uint256 balance = address(this).balance;
		companyWallet.transfer(balance);
	}
	
  function presales(
    address _initialOwner,
    uint256 _initialSupply,
    bytes calldata _sig,
    bytes calldata _data
  ) external payable returns (uint256) {
    require(salesStage == 1 || salesStage == 2, "Presales is closed");
    require(sold + _initialSupply <= totalTokenAssets, "Max Token Minted");
    require(isValidData(addressToString(msg.sender), _sig), addressToString(msg.sender));

    if(salesStage == 1){
      require(presales1Minted + _initialSupply <= presales1MaxToken, "Max Token Minted");
      require(_initialSupply * preSalesPrice1 == msg.value , "Invalid Fund");
    }else if(salesStage == 2){
      require(presales2Minted + _initialSupply <= presales2MaxToken, "Max Token Minted");
      require(_initialSupply * preSalesPrice2 == msg.value , "Invalid Fund");
    }
    
    sold += _initialSupply;

    if(salesStage == 1){
      presales1minted[_initialOwner] += _initialSupply;
      presales1Minted += _initialSupply;
    }else if(salesStage == 2){
      presales2minted[_initialOwner] += _initialSupply;
      presales2Minted += _initialSupply;
    }

    minted[_initialOwner] += _initialSupply;

    for (uint256 i = 0; i < _initialSupply; i++) {
      uint256 _id = _getNextTokenID() + totalReserve;
      _incrementTokenTypeId();
      creators[_id] = msg.sender;
      _mint(_initialOwner, _id, 1, _data);
      tokenSupply[_id] = 1;
    }

    return 0;
  }


  function publicsales(
    address _initialOwner,
    uint256 _initialSupply,
    string calldata _uri,
    bytes calldata _data
  ) external payable returns (uint256) {
    require(salesStage == 3 , "Public Sales Is Closed");
    require(_initialSupply * publicSalesPrice == msg.value , "Invalid Fund");
    require(sold + _initialSupply <= totalTokenAssets, "Max Token Minted");

    sold += _initialSupply;
    minted[_initialOwner] += _initialSupply;

    for (uint256 i = 0; i < _initialSupply; i++) {
      uint256 _id = _getNextTokenID() + totalReserve;
      _incrementTokenTypeId();

     if (bytes(_uri).length > 0) {
       emit URI(_uri, _id);
     }

      creators[_id] = msg.sender;
      _mint(_initialOwner, _id, 1, _data);
      tokenSupply[_id] = 1;
    }
    return 0;
  }

  function setSalesStage(
    uint16 stage
  ) public onlyOwner {
      salesStage = stage;
  }

  function setCompanyWallet(
    address payable newWallet
  ) public onlyOwner {
      companyWallet = newWallet;
  }

  
  function ownerMint(
    address _initialOwner,
    uint256 _initialSupply,
    string calldata _uri,
    bytes calldata _data
  ) external onlyOwner returns (uint256) {
    require(sold + _initialSupply <= totalTokenAssets, "Max Token Minted");

    sold += _initialSupply;
    
    for (uint256 i = 0; i < _initialSupply; i++) {
        uint256 _id = _getNextTokenID() + totalReserve;
        _incrementTokenTypeId();

      if (bytes(_uri).length > 0) {
        emit URI(_uri, _id);
      }


      creators[_id] = msg.sender;
      _mint(_initialOwner, _id, 1, _data);
      tokenSupply[_id] = 1;
    }
    return 0;
  }
  
  function walletbalance(
  ) public view returns (uint256) {
        return address(this).balance;
    }
  

  /**
    * @dev Mint tokens for each id in _ids
    * @param _to          The address to mint tokens to
    * @param _ids         Array of ids to mint
    * @param _quantities  Array of amounts of tokens to mint per id
    * @param _data        Data to pass if receiver is contract
    */
  function batchMint(
    address _to,
    uint256[] memory _ids,
    uint256[] memory _quantities,
    bytes memory _data
  ) public {
    for (uint256 i = 0; i < _ids.length; i++) {
      uint256 _id = _ids[i];
      require(creators[_id] == msg.sender, "ERC1155Tradable#batchMint: ONLY_CREATOR_ALLOWED");
      uint256 quantity = _quantities[i];
      tokenSupply[_id] = tokenSupply[_id].add(quantity);
    }
    _batchMint(_to, _ids, _quantities, _data);
  }

  /**
    * @dev Change the creator address for given tokens
    * @param _to   Address of the new creator
    * @param _ids  Array of Token IDs to change creator
    */
  function setCreator(
    address _to,
    uint256[] memory _ids
  ) public {
    require(_to != address(0), "ERC1155Tradable#setCreator: INVALID_ADDRESS.");
    for (uint256 i = 0; i < _ids.length; i++) {
      uint256 id = _ids[i];
      _setCreator(_to, id);
    }
  }

  /**
   * Override isApprovedForAll to whitelist user's OpenSea proxy accounts to enable gas-free listings.
   */
  //function isApprovedForAll(
  //  address _owner,
  //  address _operator
  //) 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 ERC1155.isApprovedForAll(_owner, _operator);
  //}

  /**
    * @dev Change the creator address for given token
    * @param _to   Address of the new creator
    * @param _id  Token IDs to change creator of
    */
  function _setCreator(address _to, uint256 _id) internal creatorOnly(_id)
  {
      creators[_id] = _to;
  }

  /**
    * @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++;
  }
}

// File: contracts\MyCollectible.sol

pragma solidity ^0.5.12;


/**
 * @title MyCollectible
 * MyCollectible - a contract for my semi-fungible tokens.
 */
contract GOFWorld is ERC1155Tradable {
  constructor(string memory _name)
  ERC1155Tradable(
    _name,
    _name
  ) public {
    _setBaseMetadataURI("https://api.gofworld.io/nft/");
  }

}