// File: /contracts/proxy/ERC721GenMintTransferProxy.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.2 <0.8.0;
pragma abicoder v2;

import "@rarible/exchange-interfaces/contracts/ITransferProxy.sol";
import "../interfaces/IERC721GenMint.sol";
import "../roles/OperatorRole.sol";

//transfer proxy that is going to mint tokens (operator proxy)
contract ERC721GenMintTransferProxy is ITransferProxy, OperatorRole {
    function transfer(LibAsset.Asset memory asset, address from, address to) external override {
        address token = abi.decode(asset.assetType.data, (address));
        IERC721GenMint(token).mint(from, to, asset.value);
    }
}

// File: /contracts/roles/OperatorRole.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.9 <0.8.0;

import "@openzeppelin/contracts/access/Ownable.sol";

//operator role
contract OperatorRole is Ownable {
    mapping (address => bool) operators;

    function addOperator(address operator) external onlyOwner {
        operators[operator] = true;
    }

    function removeOperator(address operator) external onlyOwner {
        operators[operator] = false;
    }

    modifier onlyOperator() {
        require(operators[_msgSender()], "OperatorRole: caller is not the operator");
        _;
    }
}

// File: /contracts/interfaces/IERC721GenMint.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

interface IERC721GenMint {
    function mint(address artist, address to, uint value) external;
}

// File: @rarible/lib-asset/contracts/LibAsset.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.9 <0.8.0;

library LibAsset {
    bytes4 constant public ETH_ASSET_CLASS = bytes4(keccak256("ETH"));
    bytes4 constant public ERC20_ASSET_CLASS = bytes4(keccak256("ERC20"));
    bytes4 constant public ERC721_ASSET_CLASS = bytes4(keccak256("ERC721"));
    bytes4 constant public ERC1155_ASSET_CLASS = bytes4(keccak256("ERC1155"));

    bytes32 constant ASSET_TYPE_TYPEHASH = keccak256(
        "AssetType(bytes4 assetClass,bytes data)"
    );

    bytes32 constant ASSET_TYPEHASH = keccak256(
        "Asset(AssetType assetType,uint256 value)AssetType(bytes4 assetClass,bytes data)"
    );

    struct AssetType {
        bytes4 assetClass;
        bytes data;
    }

    struct Asset {
        AssetType assetType;
        uint value;
    }

    function hash(AssetType memory assetType) internal pure returns (bytes32) {
        return keccak256(abi.encode(
                ASSET_TYPE_TYPEHASH,
                assetType.assetClass,
                keccak256(assetType.data)
            ));
    }

    function hash(Asset memory asset) internal pure returns (bytes32) {
        return keccak256(abi.encode(
                ASSET_TYPEHASH,
                hash(asset.assetType),
                asset.value
            ));
    }

}

// File: @rarible/exchange-interfaces/contracts/ITransferProxy.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.9 <0.8.0;
pragma abicoder v2;

import "@rarible/lib-asset/contracts/LibAsset.sol";

interface ITransferProxy {
    function transfer(LibAsset.Asset calldata asset, address from, address to) external;
}

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



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with 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 payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

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



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "../utils/Context.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        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 virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}