mchess-client/lib/chess/chess_square_outer_dragtarget.dart

import 'package:flutter/material.dart';
import 'package:mchess/chess/chess_square_inner_draggable.dart';
import 'package:mchess/chess_bloc/chess_bloc.dart';
import 'package:mchess/chess_bloc/chess_events.dart';
import 'package:mchess/chess_bloc/promotion_bloc.dart';
import 'package:mchess/utils/chess_utils.dart';

class ChessSquareOuterDragTarget extends StatelessWidget {
  final ChessCoordinate coordinate;
  final ChessPiece containedPiece;

  const ChessSquareOuterDragTarget(
      {super.key, required this.coordinate, required this.containedPiece});

  @override
  Widget build(BuildContext context) {
    return DragTarget<PieceDragged>(
      onWillAccept: (move) {
        if (move?.fromSquare == coordinate) {
          return false;
        }
        return true;
      },
      onAccept: (pieceDragged) {
        // Replace the dummy value with the actual target of the move.
        pieceDragged.toSquare = coordinate;

        if (isPromotionMove(
          pieceDragged.movedPiece!.pieceClass,
          ChessBloc.myColor!,
          pieceDragged.toSquare,
        )) {
          var move = ChessMove(
              from: pieceDragged.fromSquare, to: pieceDragged.toSquare);
          PromotionBloc().add(PawnMovedToPromotionField(
              move: move, colorMoved: ChessBloc.myColor!));
        } else if (coordinate != pieceDragged.fromSquare) {
          ChessBloc().add(OwnPieceMoved(
              startSquare: pieceDragged.fromSquare,
              endSquare: pieceDragged.toSquare));
        }
      },
      builder: (context, candidateData, rejectedData) {
        return ChessSquareInnerDraggable(
          coordinate: coordinate,
          containedPiece: containedPiece,
        );
      },
    );
  }
}