BlockSeasons/lib/ui/widgets/board_widget.dart

import 'package:flutter/material.dart';

import '../../state/game_session_notifier.dart';
import 'board_painter.dart';

/// The board with clear-flash and combo-text effects. Pure display: drag
/// orchestration lives in the game screen.
class BoardWidget extends StatefulWidget {
  const BoardWidget({super.key, required this.view, required this.ghost});

  final GameViewState view;
  final GhostSpec? ghost;

  @override
  State<BoardWidget> createState() => _BoardWidgetState();
}

class _BoardWidgetState extends State<BoardWidget>
    with SingleTickerProviderStateMixin {
  late final AnimationController _flash = AnimationController(
    vsync: this,
    duration: const Duration(milliseconds: 350),
  );

  List<int> _flashRows = const [];
  List<int> _flashCols = const [];
  int _comboStreak = 0;

  @override
  void didUpdateWidget(BoardWidget old) {
    super.didUpdateWidget(old);
    final placement = widget.view.lastPlacement;
    if (widget.view.fxTick != old.view.fxTick &&
        placement != null &&
        placement.linesCleared > 0) {
      _flashRows = placement.clearedRows;
      _flashCols = placement.clearedCols;
      _comboStreak = placement.comboStreak;
      _flash.forward(from: 0);
    }
  }

  @override
  void dispose() {
    _flash.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return AspectRatio(
      aspectRatio: 1,
      child: AnimatedBuilder(
        animation: _flash,
        builder: (context, _) {
          final fading = _flash.isAnimating ? 1 - _flash.value : 0.0;
          return Stack(
            fit: StackFit.expand,
            children: [
              CustomPaint(
                painter: BoardPainter(
                  grid: widget.view.grid,
                  ghost: widget.ghost,
                  flashProgress: fading,
                  flashRows: _flashRows,
                  flashCols: _flashCols,
                ),
              ),
              if (_flash.isAnimating && _comboStreak >= 2)
                Center(
                  child: Transform.scale(
                    scale: 0.8 + 0.6 * _flash.value,
                    child: Opacity(
                      opacity: 1 - _flash.value,
                      child: Text(
                        'COMBO x$_comboStreak',
                        style: TextStyle(
                          fontSize: 36,
                          fontWeight: FontWeight.w900,
                          color: Colors.amber.shade300,
                          shadows: const [
                            Shadow(blurRadius: 12, color: Colors.black54),
                          ],
                        ),
                      ),
                    ),
                  ),
                ),
            ],
          );
        },
      ),
    );
  }
}