pragma solidity 0.5.10;

import "./Proxy.sol";


/// @title Proxy Factory - Allows to create new proxy contract and execute a message call to the new proxy within one transaction.
/// @author Stefan George - <stefan@gnosis.pm>
contract ProxyFactory {

  event ProxyCreation(Proxy proxy);

  /// @dev Allows to create new proxy contact and execute a message call to the new proxy within one transaction.
  /// @param masterCopy Address of master copy.
  /// @param data Payload for message call sent to new proxy contract.
  function createProxy(address masterCopy, bytes memory data)
    public
    returns (Proxy proxy)
  {
    proxy = new Proxy(masterCopy);
    if (data.length > 0)
      // solium-disable-next-line security/no-inline-assembly
      assembly {
        if eq(call(gas, proxy, 0, add(data, 0x20), mload(data), 0, 0), 0) { revert(0, 0) }
      }
    emit ProxyCreation(proxy);
  }

  /// @dev Allows to retrieve the runtime code of a deployed Proxy. This can be used to check that the expected Proxy was deployed.
  function proxyRuntimeCode() public pure returns (bytes memory) {
    return type(Proxy).runtimeCode;
  }

  /// @dev Allows to retrieve the creation code used for the Proxy deployment. With this it is easily possible to calculate predicted address.
  function proxyCreationCode() public pure returns (bytes memory) {
    return type(Proxy).creationCode;
  }

  /// @dev Allows to create new proxy contact and execute a message call to the new proxy within one transaction.
  /// @param _mastercopy Address of master copy.
  /// @param initializer Payload for message call sent to new proxy contract.
  /// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
  function createProxyWithNonce(
    address _mastercopy,
    bytes memory initializer,
    uint256 saltNonce
  )
    public
    returns (Proxy proxy)
  {
    // If the initializer changes, the proxy address should change too. Hashing the initializer data is cheaper than just concatinating it
    bytes32 salt = keccak256(
      abi.encodePacked(keccak256(initializer), saltNonce)
    );

    bytes memory deploymentData = abi.encodePacked(
      type(Proxy).creationCode,
      uint256(_mastercopy)
    );

    // solium-disable-next-line security/no-inline-assembly
    assembly {
      proxy := create2(0x0, add(0x20, deploymentData), mload(deploymentData), salt)
    }

    if (initializer.length > 0)
      // solium-disable-next-line security/no-inline-assembly
      assembly {
        if eq(call(gas, proxy, 0, add(initializer, 0x20), mload(initializer), 0, 0), 0) { revert(0,0) }
      }

    emit ProxyCreation(proxy);
  }
}