mchess-client/lib/chess_bloc/chess_bloc.dart

import 'dart:async';

import 'package:flutter_bloc/flutter_bloc.dart';

import 'package:mchess/chessapp/chess_utils.dart';
import 'package:mchess/chessapp/chess_square.dart';

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

  ChessBloc._internal() : super(ChessBoardState.init()) {
    on<PieceMoved>(moveHandler);
  }

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

  factory ChessBloc() {
    return _instance;
  }

  FutureOr<void> moveHandler(
    PieceMoved event,
    Emitter<ChessBoardState> emit,
  ) {
    emit(ChessBoardState(
      !state.flipped,
      ChessColor.black,
      state.position,
    ));
  }
}

abstract class ChessEvent {}

class PieceMoved extends ChessEvent {}

class BoardFlippedEvent extends ChessEvent {}

class ChessBoardState {
  final bool flipped;
  final ChessColor turnColor;
  final Map<ChessCoordinate, ChessPiece> position;

  ChessBoardState(this.flipped, this.turnColor, this.position);

  ChessBoardState.init()
      : flipped = false,
        turnColor = ChessColor.white,
        position = {};
}