//
//  EngineResponse.swift
//  ChessKitEngine
//

/// Possible engine responses based on the
/// [Universal Chess Interface (UCI)](https://backscattering.de/chess/uci/2006-04.txt).
public enum EngineResponse: Sendable {

  /// `"id name <x>"`, `"id author <x>"`
  ///
  /// See [UCI protocol documentation](https://backscattering.de/chess/uci/2006-04.txt)
  /// for more information.
  case id(ID)

  /// `"uciok"`
  ///
  /// See [UCI protocol documentation](https://backscattering.de/chess/uci/2006-04.txt)
  /// for more information.
  case uciok

  /// `"readyok"`
  ///
  /// See [UCI protocol documentation](https://backscattering.de/chess/uci/2006-04.txt)
  /// for more information.
  case readyok

  /// `"bestmove <move1> [ ponder <move2> ]"`
  ///
  /// See [UCI protocol documentation](https://backscattering.de/chess/uci/2006-04.txt)
  /// for more information.
  case bestmove(move: String, ponder: String?)

  /// `"info"`
  ///
  /// See [UCI protocol documentation](https://backscattering.de/chess/uci/2006-04.txt)
  /// for more information.
  case info(Info)

}

extension EngineResponse: Equatable {}

extension EngineResponse: RawRepresentable {
  public init?(rawValue: String) {
    let parsed = EngineResponseParser.parse(response: rawValue)

    guard let parsed else {
      return nil
    }

    self = parsed
  }

  public var rawValue: String {
    switch self {
    case let .id(id):
      switch id {
      case let .name(name):
        "<id> <name> \(name)"
      case let .author(author):
        "<id> <author> \(author)"
      }
    case .uciok:
      "<uciok>"
    case .readyok:
      "<readyok>"
    case let .bestmove(move, ponder):
      if let ponder {
        "<bestmove> \(move) <ponder> \(ponder)"
      } else {
        "<bestmove> \(move)"
      }
    case let .info(info):
      "<info>\(info)"
    }
  }
}