import 'package:flutter/material.dart';

/// ====================================================================
/// 1. KRSimpleLoading: 旋转和扇形加载动画 (支持暂停，已修复重合)
/// ====================================================================
class KRSimpleLoading extends StatefulWidget {
  final Color? color;
  final double size;
  final Duration duration;
  final bool isPaused; // 控制动画暂停/恢复

  const KRSimpleLoading({
    super.key,
    this.color,
    this.size = 30.0, // 环的宽高默认为 30.0 像素
    this.duration = const Duration(milliseconds: 1000),
    this.isPaused = false, // 默认不暂停
  });

  @override
  State<KRSimpleLoading> createState() => _KRSimpleLoadingState();
}

class _KRSimpleLoadingState extends State<KRSimpleLoading>
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;
  late Animation<double> _rotationAnimation;

  // 环的宽度 5px
  static const double _strokeWidth = 5.0;

  @override
  void initState() {
    super.initState();

    _controller = AnimationController(
      duration: widget.duration,
      vsync: this,
    );

    _rotationAnimation = Tween<double>(
      begin: 0.0,
      end: 1.0,
    ).animate(CurvedAnimation(
      parent: _controller,
      curve: Curves.linear,
    ));

    // 根据初始状态决定是重复播放还是停止
    _setAnimationState(widget.isPaused);
  }

  void _setAnimationState(bool isPaused) {
    if (isPaused) {
      _controller.stop();
    } else {
      // 如果之前停止了，调用 repeat 重新开始
      _controller.repeat();
    }
  }

  @override
  void didUpdateWidget(covariant KRSimpleLoading oldWidget) {
    super.didUpdateWidget(oldWidget);
    // 监听 isPaused 参数的变化，并更新动画状态
    if (widget.isPaused != oldWidget.isPaused) {
      _setAnimationState(widget.isPaused);
    }
  }

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

  @override
  Widget build(BuildContext context) {
    final defaultColor = widget.color ?? Theme.of(context).primaryColor;

    // 强制动画组件拥有固定的 30x30 尺寸
    return SizedBox(
      width: widget.size,
      height: widget.size,
      child: AnimatedBuilder(
        animation: _controller,
        builder: (context, child) {
          return Transform.rotate(
            angle: _rotationAnimation.value * 2 * 3.14159,
            // 关键修复: 使用 Stack 和 Center+SizedBox 确保两个环完美重合
            child: Stack(
              children: [
                // 1. 底环 (Container): 绘制 30x30 边界内的 5px 边框
                Positioned.fill(
                  child: Container(
                    decoration: BoxDecoration(
                      shape: BoxShape.circle,
                      border: Border.all(
                        color: defaultColor.withOpacity(0.3),
                        width: _strokeWidth,
                      ),
                    ),
                  ),
                ),
                // 2. 顶扇形 (CircularProgressIndicator):
                //    通过 Center+SizedBox 强制其绘制区域收缩，以消除渲染偏差。
                Center(
                  child: SizedBox(
                    // 关键：将尺寸减去笔触宽度 (30 - 5 = 25)
                    width: widget.size - _strokeWidth,
                    height: widget.size - _strokeWidth,
                    child: CircularProgressIndicator(
                      value: 0.2, // 彩色扇形长度
                      strokeCap: StrokeCap.round, // 圆角
                      strokeWidth: _strokeWidth, // 宽度 5px
                      backgroundColor: Colors.transparent, // 必须透明
                      valueColor: AlwaysStoppedAnimation<Color>(
                        defaultColor,
                      ),
                    ),
                  ),
                ),
              ],
            ),
          );
        },
      ),
    );
  }
}
class KRSimplePulse extends StatefulWidget {
  final Color? color;
  final double size;
  final Duration duration;

  const KRSimplePulse({
    super.key,
    this.color,
    this.size = 40.0,
    this.duration = const Duration(milliseconds: 1500),
  });

  @override
  State<KRSimplePulse> createState() => _KRSimplePulseState();
}

class _KRSimplePulseState extends State<KRSimplePulse>
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;
  late Animation<double> _animation;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      duration: widget.duration,
      vsync: this,
    );
    _animation = Tween<double>(
      begin: 0.0,
      end: 1.0,
    ).animate(CurvedAnimation(
      parent: _controller,
      curve: Curves.easeInOut,
    ));
    _controller.repeat();
  }

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

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: _animation,
      builder: (context, child) {
        return Transform.scale(
          scale: 0.5 + (_animation.value * 0.5),
          child: Opacity(
            opacity: 1.0 - _animation.value,
            child: Container(
              width: widget.size,
              height: widget.size,
              decoration: BoxDecoration(
                shape: BoxShape.circle,
                color: widget.color ?? Theme.of(context).primaryColor,
              ),
            ),
          ),
        );
      },
    );
  }
}

/// 波浪加载动画
class KRSimpleWave extends StatefulWidget {
  final Color? color;
  final double size;
  final Duration duration;

  const KRSimpleWave({
    super.key,
    this.color,
    this.size = 40.0,
    this.duration = const Duration(milliseconds: 1200),
  });

  @override
  State<KRSimpleWave> createState() => _KRSimpleWaveState();
}

class _KRSimpleWaveState extends State<KRSimpleWave>
    with TickerProviderStateMixin {
  late List<AnimationController> _controllers;
  late List<Animation<double>> _animations;

  @override
  void initState() {
    super.initState();
    _controllers = List.generate(3, (index) {
      return AnimationController(
        duration: widget.duration,
        vsync: this,
      );
    });
    
    _animations = _controllers.map((controller) {
      return Tween<double>(
        begin: 0.0,
        end: 1.0,
      ).animate(CurvedAnimation(
        parent: controller,
        curve: Curves.easeInOut,
      ));
    }).toList();

    for (int i = 0; i < _controllers.length; i++) {
      Future.delayed(Duration(milliseconds: i * 200), () {
        if (mounted) {
          _controllers[i].repeat();
        }
      });
    }
  }

  @override
  void dispose() {
    for (var controller in _controllers) {
      controller.dispose();
    }
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Row(
      mainAxisSize: MainAxisSize.min,
      children: List.generate(3, (index) {
        return AnimatedBuilder(
          animation: _animations[index],
          builder: (context, child) {
            return Container(
              margin: const EdgeInsets.symmetric(horizontal: 2.0),
              width: widget.size / 6,
              height: widget.size * (0.3 + (_animations[index].value * 0.7)),
              decoration: BoxDecoration(
                color: widget.color ?? Theme.of(context).primaryColor,
                borderRadius: BorderRadius.circular(2.0),
              ),
            );
          },
        );
      }),
    );
  }
}