// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

// End consumer library.
library Client {
  /// @dev RMN depends on this struct, if changing, please notify the RMN maintainers.
  struct EVMTokenAmount {
    address token; // token address on the local chain.
    uint256 amount; // Amount of tokens.
  }

  struct Any2EVMMessage {
    bytes32 messageId; // MessageId corresponding to ccipSend on source.
    uint64 sourceChainSelector; // Source chain selector.
    bytes sender; // abi.decode(sender) if coming from an EVM chain.
    bytes data; // payload sent in original message.
    EVMTokenAmount[] destTokenAmounts; // Tokens and their amounts in their destination chain representation.
  }

  // If extraArgs is empty bytes, the default is 200k gas limit.
  struct EVM2AnyMessage {
    bytes receiver; // abi.encode(receiver address) for dest EVM chains
    bytes data; // Data payload
    EVMTokenAmount[] tokenAmounts; // Token transfers
    address feeToken; // Address of feeToken. address(0) means you will send msg.value.
    bytes extraArgs; // Populate this with _argsToBytes(EVMExtraArgsV2)
  }

  // bytes4(keccak256("CCIP EVMExtraArgsV1"));
  bytes4 public constant EVM_EXTRA_ARGS_V1_TAG = 0x97a657c9;

  struct EVMExtraArgsV1 {
    uint256 gasLimit;
  }

  function _argsToBytes(EVMExtraArgsV1 memory extraArgs) internal pure returns (bytes memory bts) {
    return abi.encodeWithSelector(EVM_EXTRA_ARGS_V1_TAG, extraArgs);
  }

  // bytes4(keccak256("CCIP EVMExtraArgsV2"));
  bytes4 public constant EVM_EXTRA_ARGS_V2_TAG = 0x181dcf10;

  /// @param gasLimit: gas limit for the callback on the destination chain.
  /// @param allowOutOfOrderExecution: if true, it indicates that the message can be executed in any order relative to other messages from the same sender.
  /// This value's default varies by chain. On some chains, a particular value is enforced, meaning if the expected value
  /// is not set, the message request will revert.
  struct EVMExtraArgsV2 {
    uint256 gasLimit;
    bool allowOutOfOrderExecution;
  }

  function _argsToBytes(EVMExtraArgsV2 memory extraArgs) internal pure returns (bytes memory bts) {
    return abi.encodeWithSelector(EVM_EXTRA_ARGS_V2_TAG, extraArgs);
  }
}