mchess-client/lib/chess_bloc/chess_bloc.dart

import 'dart:convert';
import 'dart:developer';

import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:mchess/api/websocket_message.dart';
import 'package:mchess/chess_bloc/chess_events.dart';
import 'package:mchess/chess_bloc/chess_position.dart';
import 'package:mchess/connection/ws_connection.dart';
import 'package:mchess/utils/chess_utils.dart';

class ChessBloc extends Bloc<ChessEvent, ChessBoardState> {
  static final ChessBloc _instance = ChessBloc._internal();
  static ChessColor turnColor = ChessColor.white;
  static ChessColor myColor = ChessColor.white;

  static ChessColor getMyColor() {
    return myColor;
  }

  ChessBloc._internal() : super(ChessBoardState.init()) {
    on<InitBoard>(initBoard);
    on<ColorDetermined>(flipBoard);
    on<ReceivedBoardState>(moveAndPositionHandler);
    on<OwnPieceMoved>(ownMoveHandler);
    on<OwnPromotionPlayed>(ownPromotionHandler);
    on<InvalidMovePlayed>(invalidMoveHandler);
  }

  factory ChessBloc.getInstance() {
    return ChessBloc();
  }

  factory ChessBloc() {
    return _instance;
  }

  void initBoard(InitBoard event, Emitter<ChessBoardState> emit) {
    turnColor = ChessColor.white;
    ChessPositionManager.getInstance().resetToStartingPosition();
    emit(
      ChessBoardState(
        ChessColor.white,
        ChessColor.white,
        ChessPositionManager.getInstance().currentPosition,
        ChessMove.none(),
        false,
        ChessCoordinate.none(),
      ),
    );
  }

  void flipBoard(ColorDetermined event, Emitter<ChessBoardState> emit) {
    log("My Color is $myColor");

    myColor = event.playerColor;

    emit(
      ChessBoardState(
        event.playerColor,
        state.newTurnColor,
        state.position,
        ChessMove.none(),
        false,
        ChessCoordinate.none(),
      ),
    );
  }

  void moveAndPositionHandler(
      ReceivedBoardState event, Emitter<ChessBoardState> emit) {
    ChessMove? move;
    if (event.startSquare != ChessCoordinate.none() &&
        event.endSquare != ChessCoordinate.none()) {
      move = ChessMove(from: event.startSquare!, to: event.endSquare!);
      ChessPositionManager.getInstance()
          .recordMove(event.startSquare, event.endSquare, event.position);
    }

    myColor = event.playerColor;
    turnColor = event.turnColor;

    emit(
      ChessBoardState(
        myColor,
        event.turnColor,
        event.position,
        move,
        true,
        event.squareInCheck,
      ),
    );
  }

  void ownMoveHandler(OwnPieceMoved event, Emitter<ChessBoardState> emit) {
    log('ownMoveHandler()');
    var apiMove =
        ChessMove(from: event.startSquare, to: event.endSquare).toApiMove();
    var apiMessage = ApiWebsocketMessage(
      type: MessageType.move,
      move: apiMove,
      turnColor: null,
      reason: null,
      position: null,
      squareInCheck: null,
      playerColor: null,
    );

    ServerConnection.getInstance().send(jsonEncode(apiMessage));

    //Temporary chess position until server responds with acknowledgement
    var move = ChessMove.fromApiMove(apiMove);
    var tempPosition = ChessPositionManager.getInstance().copyOfCurrentPosition;
    tempPosition[move.to] = tempPosition[move.from] ?? const ChessPiece.none();
    tempPosition[move.from] = const ChessPiece.none();

    emit(
      ChessBoardState(
        state.bottomColor,
        turnColor,
        tempPosition,
        ChessPositionManager.getInstance().lastMove,
        true,
        ChessCoordinate.none(),
      ),
    );
  }

  void ownPromotionHandler(
      OwnPromotionPlayed event, Emitter<ChessBoardState> emit) {
    var apiMove = event.move.toApiMove();
    var shorNameForPiece = chessPiecesShortName[
        ChessPieceAssetKey(pieceClass: event.pieceClass, color: myColor)]!;
    apiMove.promotionToPiece = shorNameForPiece;
    var message = ApiWebsocketMessage(
      type: MessageType.move,
      move: apiMove,
      turnColor: null,
      reason: null,
      position: null,
      squareInCheck: null,
      playerColor: null,
    );
    log(jsonEncode(message));
    ServerConnection.getInstance().send(jsonEncode(message));
  }

  void invalidMoveHandler(
      InvalidMovePlayed event, Emitter<ChessBoardState> emit) {
    var move = ChessPositionManager.getInstance().lastMove;
    emit(
      ChessBoardState(
        state.bottomColor,
        turnColor,
        ChessPositionManager.getInstance().currentPosition,
        move,
        true,
        event.squareInCheck,
      ),
    );
  }
}

class ChessBoardState {
  final ChessColor bottomColor;
  final ChessColor newTurnColor;
  final ChessPosition position;
  final ChessMove lastMove;
  final bool colorLastMove;
  final ChessCoordinate squareInCheck;

  ChessBoardState._(
    this.bottomColor,
    this.newTurnColor,
    this.position,
    this.lastMove,
    this.colorLastMove,
    this.squareInCheck,
  );

  factory ChessBoardState(
    ChessColor bottomColor,
    ChessColor turnColor,
    ChessPosition position,
    ChessMove? lastMove,
    bool positionAckd,
    ChessCoordinate squareInCheck,
  ) {
    return ChessBoardState._(bottomColor, turnColor, position,
        lastMove ?? ChessMove.none(), positionAckd, squareInCheck);
  }

  factory ChessBoardState.init() {
    ChessColor bottomColor = ChessColor.white;
    ChessColor turnColor = ChessColor.white;

    ChessPositionManager.getInstance().resetToStartingPosition();

    return ChessBoardState(
      bottomColor,
      turnColor,
      ChessPositionManager.getInstance().currentPosition,
      ChessMove.none(),
      false,
      ChessCoordinate.none(),
    );
  }

  void logPosition(Map<ChessCoordinate, ChessPiece> pos) {
    // for (int i = 0; i < 7; i++)
  }
}