// File: contracts/Registry.sol



// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.9.0;
// import "@openzeppelin/contracts/access/Ownable.sol";
import "./Ownable.sol";

contract Registry is Ownable {

  event ContractAddressUpdated(
    string indexed _name,
    bytes32 indexed _code,
    address indexed _newAddress
  );

  event TokenMapped(
    address indexed _mainchainToken,
    string indexed _sidechainToken,
    uint32 _standard
  );

  string public constant GATEWAY = "GATEWAY";
  string public constant WETH_TOKEN = "WETH_TOKEN";
  string public constant VALIDATOR = "VALIDATOR";
  string public constant ACKNOWLEDGEMENT = "ACKNOWLEDGEMENT";

  struct TokenMapping {
    address mainchainToken;
    string sidechainToken;
    uint32 standard; // 20, 721 or any other standards
  }

  mapping(bytes32 => address) public contractAddresses;
  mapping(address => TokenMapping) public mainchainMap;
  // mapping(address => TokenMapping) public sidechainMap;

  function getContract(string calldata _name)
    external
    view
    returns (address _address)
  {
    bytes32 _code = getCode(_name);
    _address = contractAddresses[_code];
    require(_address != address(0));
  }

  function isTokenMapped(address _token, uint32 _standard)
    external
    view
    returns (bool)
  {
    TokenMapping memory _mapping = _getTokenMapping(_token);

    return _mapping.mainchainToken != address(0) &&
    // keccak256(bytes(mainchainMap[_token])) != keccak256("")
      _mapping.standard == _standard;
  }

  function updateContract(string calldata _name, address _newAddress)
    external
    onlyOwner
  {
    bytes32 _code = getCode(_name);
    contractAddresses[_code] = _newAddress;

    emit ContractAddressUpdated(_name, _code, _newAddress);
  }

  function mapToken(address _mainchainToken, string memory _sidechainToken, uint32 _standard)
    external
    onlyOwner
  {
    TokenMapping memory _map = TokenMapping(
      _mainchainToken,
      _sidechainToken,
      _standard
    );

    mainchainMap[_mainchainToken] = _map;

    emit TokenMapped(
      _mainchainToken,
      _sidechainToken,
      _standard
    );
  }

  function clearMapToken(address _mainchainToken)
    external
    onlyOwner
  {
    TokenMapping storage _mainchainMap = mainchainMap[_mainchainToken];
    _clearMapEntry(_mainchainMap);

    // TokenMapping storage _sidechainMap = sidechainMap[_sidechainToken];
    // _clearMapEntry(_sidechainMap);
  }

  function getMappedToken(
    address _token
  )
    external
    view
  returns (
    address _mainchainToken,
    string memory _sidechainToken,
    uint32 _standard
  )
  {
    TokenMapping memory _mapping = _getTokenMapping(_token);
    _mainchainToken = _mapping.mainchainToken;
    _sidechainToken = _mapping.sidechainToken;
    _standard = _mapping.standard;
  }

  function getCode(string memory _name)
    public
    pure
    returns (bytes32)
  {
    return keccak256(abi.encodePacked(_name));
  }

  function _getTokenMapping(
    address _token
  )
    internal
    view
    returns (TokenMapping memory _mapping)
  {
      _mapping = mainchainMap[_token];
  }

  function _clearMapEntry(TokenMapping storage _entry)
    internal
  {
    _entry.mainchainToken = address(0);
    _entry.sidechainToken = "";
    _entry.standard = 0;
  }
}
// File: contracts/Ownable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "@openzeppelin/contracts/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() {
        _setOwner(_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 {
        _setOwner(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");
        _setOwner(newOwner);
    }

    function _setOwner(address newOwner) internal {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

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

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