submanager/lib/widgets/common/dialogs/loading_overlay.dart

import 'package:flutter/material.dart';

/// 로딩 오버레이 위젯
/// 비동기 작업 중 화면을 덮는 로딩 인디케이터를 표시합니다.
class LoadingOverlay extends StatelessWidget {
  final bool isLoading;
  final Widget child;
  final String? message;
  final Color? backgroundColor;
  final Color? indicatorColor;
  final double opacity;

  const LoadingOverlay({
    super.key,
    required this.isLoading,
    required this.child,
    this.message,
    this.backgroundColor,
    this.indicatorColor,
    this.opacity = 0.7,
  });

  @override
  Widget build(BuildContext context) {
    return Stack(
      children: [
        child,
        if (isLoading)
          Container(
            color: (backgroundColor ?? Colors.black).withValues(alpha: opacity),
            child: Center(
              child: Container(
                padding: const EdgeInsets.all(24),
                decoration: BoxDecoration(
                  color: Colors.white,
                  borderRadius: BorderRadius.circular(16),
                  boxShadow: [
                    BoxShadow(
                      color: Colors.black.withValues(alpha: 0.1),
                      blurRadius: 10,
                      offset: const Offset(0, 4),
                    ),
                  ],
                ),
                child: Column(
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    CircularProgressIndicator(
                      color: indicatorColor ?? Theme.of(context).primaryColor,
                    ),
                    if (message != null) ...[
                      const SizedBox(height: 16),
                      Text(
                        message!,
                        style: const TextStyle(
                          fontSize: 16,
                          fontWeight: FontWeight.w500,
                        ),
                      ),
                    ],
                  ],
                ),
              ),
            ),
          ),
      ],
    );
  }
}

/// 로딩 다이얼로그
/// 모달 형태의 로딩 인디케이터를 표시합니다.
class LoadingDialog {
  static Future<void> show({
    required BuildContext context,
    String? message,
    Color? barrierColor,
    bool barrierDismissible = false,
  }) {
    return showDialog(
      context: context,
      barrierDismissible: barrierDismissible,
      barrierColor: barrierColor ?? Colors.black54,
      builder: (context) => WillPopScope(
        onWillPop: () async => barrierDismissible,
        child: Center(
          child: Container(
            padding: const EdgeInsets.all(24),
            decoration: BoxDecoration(
              color: Colors.white,
              borderRadius: BorderRadius.circular(16),
            ),
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: [
                CircularProgressIndicator(
                  color: Theme.of(context).primaryColor,
                ),
                if (message != null) ...[
                  const SizedBox(height: 16),
                  Text(
                    message,
                    style: const TextStyle(
                      fontSize: 16,
                      fontWeight: FontWeight.w500,
                    ),
                  ),
                ],
              ],
            ),
          ),
        ),
      ),
    );
  }

  static void hide(BuildContext context) {
    Navigator.of(context).pop();
  }
}

/// 커스텀 로딩 인디케이터
/// 다양한 스타일의 로딩 애니메이션을 제공합니다.
class CustomLoadingIndicator extends StatefulWidget {
  final double size;
  final Color? color;
  final LoadingStyle style;

  const CustomLoadingIndicator({
    super.key,
    this.size = 50,
    this.color,
    this.style = LoadingStyle.circular,
  });

  @override
  State<CustomLoadingIndicator> createState() => _CustomLoadingIndicatorState();
}

class _CustomLoadingIndicatorState extends State<CustomLoadingIndicator>
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;
  late Animation<double> _animation;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      duration: const Duration(seconds: 1),
      vsync: this,
    )..repeat();

    _animation = CurvedAnimation(
      parent: _controller,
      curve: Curves.easeInOut,
    );
  }

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

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

    switch (widget.style) {
      case LoadingStyle.circular:
        return SizedBox(
          width: widget.size,
          height: widget.size,
          child: CircularProgressIndicator(
            color: effectiveColor,
            strokeWidth: 3,
          ),
        );

      case LoadingStyle.dots:
        return SizedBox(
          width: widget.size,
          height: widget.size / 3,
          child: Row(
            mainAxisAlignment: MainAxisAlignment.spaceEvenly,
            children: List.generate(3, (index) {
              return AnimatedBuilder(
                animation: _animation,
                builder: (context, child) {
                  final delay = index * 0.2;
                  final value = (_animation.value - delay).clamp(0.0, 1.0);
                  return Container(
                    width: widget.size / 5,
                    height: widget.size / 5,
                    decoration: BoxDecoration(
                      color: effectiveColor.withValues(alpha: 0.3 + value * 0.7),
                      shape: BoxShape.circle,
                    ),
                  );
                },
              );
            }),
          ),
        );

      case LoadingStyle.pulse:
        return AnimatedBuilder(
          animation: _animation,
          builder: (context, child) {
            return Container(
              width: widget.size,
              height: widget.size,
              decoration: BoxDecoration(
                shape: BoxShape.circle,
                color: effectiveColor.withValues(alpha: 0.3),
              ),
              child: Center(
                child: Container(
                  width: widget.size * (0.3 + _animation.value * 0.5),
                  height: widget.size * (0.3 + _animation.value * 0.5),
                  decoration: BoxDecoration(
                    shape: BoxShape.circle,
                    color: effectiveColor.withValues(alpha: 1 - _animation.value),
                  ),
                ),
              ),
            );
          },
        );
    }
  }
}

enum LoadingStyle {
  circular,
  dots,
  pulse,
}