Clean/lib/module/store/discount/func_page_view.dart

import 'dart:async';

import 'package:clean/utils/expand.dart';
import 'package:flutter/Material.dart';
import 'package:flutter_screenutil/flutter_screenutil.dart';

class InfinitePreviewPageView extends StatefulWidget {
  final List<Widget> items;
  final double height;
  final Duration autoPlayDuration;
  final bool autoPlay;

  const InfinitePreviewPageView({
    super.key,
    required this.items,
    this.height = 98,
    this.autoPlayDuration = const Duration(seconds: 3),
    this.autoPlay = true,
  });

  @override
  State<InfinitePreviewPageView> createState() => _InfinitePreviewPageViewState();
}

class _InfinitePreviewPageViewState extends State<InfinitePreviewPageView> {
  late final PageController _pageController;
  Timer? _timer;
  double _currentPage = 0;
  bool _isInitialized = false;

  // 实际页面索引
  int get _actualPage => _currentPage.round() % widget.items.length;

  @override
  void initState() {
    super.initState();
    // 设置初始页面
    final initialPage = widget.items.length * 1000;
    _currentPage = initialPage.toDouble(); // 设置初始currentPage

    _pageController = PageController(
      viewportFraction: 0.8,
      initialPage: initialPage,
    );

    _pageController.addListener(() {
      setState(() {
        _currentPage = _pageController.page ?? initialPage.toDouble();
      });
    });

    // 延迟一帧设置初始化完成
    WidgetsBinding.instance.addPostFrameCallback((_) {
      setState(() {
        _isInitialized = true;
      });
    });

    if (widget.autoPlay) {
      _startAutoPlay();
    }
  }

  void _startAutoPlay() {
    _timer?.cancel();
    _timer = Timer.periodic(widget.autoPlayDuration, (timer) {
      if (widget.items.isNotEmpty) {
        _pageController.nextPage(
          duration: const Duration(milliseconds: 300),
          curve: Curves.easeOut,
        );
      }
    });
  }

  @override
  void dispose() {
    _pageController.dispose();
    _timer?.cancel();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    if (widget.items.isEmpty) return const SizedBox();

    return SizedBox(
      height: widget.height,
      child: PageView.builder(
        controller: _pageController,
        itemBuilder: (context, index) {
          final itemIndex = index % widget.items.length;

          // 如果还没初始化完成，不应用缩放效果
          if (!_isInitialized) {
            return Padding(
              padding: const EdgeInsets.symmetric(horizontal: 8),
              child: Container(
                decoration: BoxDecoration(
                  color: const Color(0xFF1E1E1E),
                  borderRadius: BorderRadius.circular(16),
                ),
                child: widget.items[itemIndex],
              ),
            );
          }

          // 计算缩放和透明度
          double diffScale = (_currentPage - index).abs();
          double scale = 1 - (diffScale * 0.1).clamp(0.0, 0.3);
          double opacity = 1 - (diffScale * 0.3).clamp(0.0, 0.5);

          return Transform.scale(
            scale: scale,
            child: Opacity(
              opacity: opacity,
              child: Padding(
                padding: const EdgeInsets.symmetric(horizontal: 0),
                child: Container(
                  decoration: BoxDecoration(
                    color: const Color(0xFF1E1E1E),
                    borderRadius: BorderRadius.circular(23.r),
                  ),
                  child: widget.items[itemIndex],
                ),
              ),
            ),
          );
        },
      ),
    );
  }
}

// 单个项目组件
class PreviewItem extends StatelessWidget {
  final String title;
  final Image icon;
  final VoidCallback? onTap;

  const PreviewItem({
    super.key,
    required this.title,
    required this.icon,
    this.onTap,
  });

  @override
  Widget build(BuildContext context) {
    return InkWell(
      onTap: onTap,
      // borderRadius: BorderRadius.circular(16),
      child: Container(
        padding: EdgeInsets.only(left: 16.w, right: 16.w),
        decoration: BoxDecoration(
          gradient: LinearGradient(
            begin: Alignment.centerLeft,
            end: Alignment.centerRight,
            colors: [
              '#36363D'.color,
              '#18181F'.color,
            ],
          ),
          borderRadius: BorderRadius.circular(23.r),
        ),
        child: Row(
          children: [
            Container(
              width: 56.w,
              height: 56.w,
              child: icon,
            ),
            SizedBox(width: 10.w),
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Text(
                    title,
                    style: TextStyle(
                      color: Colors.white,
                      fontSize: 15.sp,
                      fontWeight: FontWeight.w500,
                    ),
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }
}