import 'dart:io'; // 导入 dart:io 以使用 File 类
import 'package:flutter/material.dart';
import 'package:flutter/widgets.dart';
import 'package:path_provider/path_provider.dart'; // 导入 path_provider
import 'package:video_thumbnail/video_thumbnail.dart'; // 导入 video_thumbnail

class VideoThumbnailImage extends StatefulWidget {
  final String videoUrl;

  VideoThumbnailImage({required this.videoUrl});

  @override
  _VideoThumbnailState createState() => _VideoThumbnailState();
}

class _VideoThumbnailState extends State<VideoThumbnailImage> {
  final Map<String, String> _thumbnailCache = {}; // 缩略图缓存
  late Future<String?> _thumbnailFuture; // 用于存储缩略图生成的 Future

  @override
  void initState() {
    super.initState();
    _thumbnailFuture = _generateThumbnail(); // 在 initState 中初始化 Future
  }

  // 生成缩略图
  Future<String?> _generateThumbnail() async {
    try {
      // 检查缓存中是否已有缩略图
      if (_thumbnailCache.containsKey(widget.videoUrl)) {
        return _thumbnailCache[widget.videoUrl];
      }

      // 获取临时目录路径
      final tempDir = await getTemporaryDirectory();
      final thumbnailPath = await VideoThumbnail.thumbnailFile(
        video: widget.videoUrl,
        // 视频 URL
        thumbnailPath: tempDir.path,
        // 缩略图保存路径
        imageFormat: ImageFormat.JPEG,
        // 缩略图格式
        maxHeight: 200,
        // 缩略图最大高度
        quality: 100, // 缩略图质量 (0-100)
      );

      // 更新缓存
      _thumbnailCache[widget.videoUrl] = thumbnailPath!;
      return thumbnailPath;
    } catch (e) {
      print('Failed to generate thumbnail: $e');
      return null;
    }
  }

  @override
  Widget build(BuildContext context) {
    return FutureBuilder<String?>(
      future: _thumbnailFuture, // 生成缩略图的 Future
      builder: (context, snapshot) {
        if (snapshot.connectionState == ConnectionState.waiting) {
          // 加载中显示转圈
          return Center(child: CircularProgressIndicator());
        } else if (snapshot.hasError || !snapshot.hasData) {
          // 加载失败或没有数据时显示提示
          return Image.asset(
            'images/icon_unHaveData.png', // 错误图片路径
            fit: BoxFit.cover,
          );
        } else {
          // 加载成功，显示缩略图
          final thumbnailPath = snapshot.data!;
          return Stack(
            alignment: Alignment.center,
            children: <Widget>[
              RotatedBox(
                quarterTurns: -1,
                child: Image.file(
                  File(thumbnailPath), // 显示生成的缩略图
                  width: 200,
                  height: 200,
                  fit: BoxFit.cover,
                ),
              ),
              Icon(
                Icons.play_arrow_rounded,
                size: 80,
                color: Colors.white.withOpacity(0.8),
              ),
            ],
          );
        }
      },
    );
  }
}