lunchpick/lib/core/widgets/skeleton_loader.dart

import 'package:flutter/material.dart';
import '../constants/app_colors.dart';
import '../constants/app_dimensions.dart';

/// Shimmer 효과를 가진 스켈톤 로더
class SkeletonLoader extends StatefulWidget {
  final double width;
  final double height;
  final double borderRadius;

  const SkeletonLoader({
    super.key,
    this.width = double.infinity,
    required this.height,
    this.borderRadius = AppDimensions.radiusSm,
  });

  @override
  State<SkeletonLoader> createState() => _SkeletonLoaderState();
}

class _SkeletonLoaderState extends State<SkeletonLoader>
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;
  late Animation<double> _animation;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      duration: const Duration(milliseconds: 1500),
      vsync: this,
    )..repeat();

    _animation = Tween<double>(begin: -1.0, end: 2.0).animate(
      CurvedAnimation(parent: _controller, curve: Curves.easeInOutSine),
    );
  }

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

  @override
  Widget build(BuildContext context) {
    final isDark = Theme.of(context).brightness == Brightness.dark;
    final baseColor = isDark
        ? AppColors.darkSurface.withValues(alpha: 0.6)
        : Colors.grey.shade300;
    final highlightColor = isDark
        ? AppColors.darkSurface.withValues(alpha: 0.9)
        : Colors.grey.shade100;

    return AnimatedBuilder(
      animation: _animation,
      builder: (context, child) {
        return Container(
          width: widget.width,
          height: widget.height,
          decoration: BoxDecoration(
            borderRadius: BorderRadius.circular(widget.borderRadius),
            gradient: LinearGradient(
              begin: Alignment.centerLeft,
              end: Alignment.centerRight,
              colors: [baseColor, highlightColor, baseColor],
              stops: [
                (_animation.value - 1).clamp(0.0, 1.0),
                _animation.value.clamp(0.0, 1.0),
                (_animation.value + 1).clamp(0.0, 1.0),
              ],
            ),
          ),
        );
      },
    );
  }
}

/// 맛집 카드 스켈톤
class RestaurantCardSkeleton extends StatelessWidget {
  const RestaurantCardSkeleton({super.key});

  @override
  Widget build(BuildContext context) {
    final isDark = Theme.of(context).brightness == Brightness.dark;

    return Card(
      margin: const EdgeInsets.symmetric(
        horizontal: AppDimensions.paddingDefault,
        vertical: AppDimensions.paddingSm,
      ),
      color: isDark ? AppColors.darkSurface : AppColors.lightSurface,
      child: Padding(
        padding: const EdgeInsets.all(AppDimensions.paddingDefault),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              children: [
                // 카테고리 아이콘 영역
                const SkeletonLoader(
                  width: AppDimensions.cardIconSize,
                  height: AppDimensions.cardIconSize,
                ),
                const SizedBox(width: AppDimensions.paddingMd),
                // 가게 정보 영역
                Expanded(
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      const SkeletonLoader(height: 20, width: 150),
                      const SizedBox(height: AppDimensions.paddingXs),
                      const SkeletonLoader(height: 14, width: 100),
                    ],
                  ),
                ),
                // 거리 배지
                const SkeletonLoader(width: 60, height: 28, borderRadius: 14),
              ],
            ),
            const SizedBox(height: AppDimensions.paddingMd),
            // 주소
            const SkeletonLoader(height: 14),
          ],
        ),
      ),
    );
  }
}

/// 맛집 리스트 스켈톤
class RestaurantListSkeleton extends StatelessWidget {
  final int itemCount;

  const RestaurantListSkeleton({super.key, this.itemCount = 5});

  @override
  Widget build(BuildContext context) {
    return ListView.builder(
      physics: const NeverScrollableScrollPhysics(),
      itemCount: itemCount,
      itemBuilder: (context, index) => const RestaurantCardSkeleton(),
    );
  }
}