gobang/lib/widgets/gobang_board.dart

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:gobang/controllers/game_controller.dart';
import 'package:gobang/models/position.dart';
import 'package:gobang/widgets/board_painter.dart';

/// 可点击的五子棋棋盘；最后一手带落子动画与高亮标记。
class GobangBoard extends StatefulWidget {
  const GobangBoard({super.key, required this.size});

  final double size;

  @override
  State<GobangBoard> createState() => _GobangBoardState();
}

class _GobangBoardState extends State<GobangBoard>
    with SingleTickerProviderStateMixin {
  late final AnimationController _controller;
  late final Animation<double> _scale;
  late final Animation<double> _pulse;
  Worker? _paintWorker;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      vsync: this,
      duration: const Duration(milliseconds: 520),
    );
    _scale = CurvedAnimation(
      parent: _controller,
      curve: const Interval(0, 0.55, curve: Curves.easeOutBack),
    );
    _pulse = TweenSequence<double>([
      TweenSequenceItem(tween: Tween(begin: 0.0, end: 1.0), weight: 1),
      TweenSequenceItem(tween: Tween(begin: 1.0, end: 0.35), weight: 1),
      TweenSequenceItem(tween: Tween(begin: 0.35, end: 0.8), weight: 1),
      TweenSequenceItem(tween: Tween(begin: 0.8, end: 0.0), weight: 1),
    ]).animate(
      CurvedAnimation(
        parent: _controller,
        curve: const Interval(0.2, 1.0, curve: Curves.easeInOut),
      ),
    );

    final c = Get.find<GameController>();
    _paintWorker = ever<int>(c.paintVersion, (_) {
      if (c.board.state.isEmpty) {
        _controller.value = 0;
        return;
      }
      _controller.forward(from: 0);
    });
  }

  @override
  void dispose() {
    _paintWorker?.dispose();
    _controller.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final c = Get.find<GameController>();
    return Obx(() {
      // 必须在 Obx 作用域内直接读取 .obs，不能放进 AnimatedBuilder
      final version = c.paintVersion.value;
      final pieces = List<Position>.unmodifiable(c.board.state);
      return GestureDetector(
        onTapDown: (d) => c.onBoardTap(d.localPosition, widget.size),
        child: AnimatedBuilder(
          animation: _controller,
          builder: (context, _) {
            return CustomPaint(
              size: Size.square(widget.size),
              painter: BoardPainter(
                pieces: pieces,
                version: version,
                lastMoveScale: _scale.value,
                lastMovePulse: _pulse.value,
              ),
            );
          },
        ),
      );
    });
  }
}