import 'package:flutter/material.dart';
import 'package:flutter_cache_manager/flutter_cache_manager.dart';
import 'package:flutter_lucide/flutter_lucide.dart';
import 'package:cached_network_image/cached_network_image.dart';
import 'package:video_player/video_player.dart';

import '../../../core/theme/app_colors.dart';
import '../../../core/theme/app_spacing.dart';

/// Video card for home grid - 点击播放按钮可在卡片上播放视频
/// 同时只能一个卡片处于播放状态
class VideoCard extends StatefulWidget {
  const VideoCard({
    super.key,
    required this.imageUrl,
    this.videoUrl,
    this.credits = '50',
    required this.isActive,
    required this.onPlayRequested,
    required this.onStopRequested,
    this.onGenerateSimilar,
  });

  final String imageUrl;
  final String? videoUrl;
  final String credits;
  final bool isActive;
  final VoidCallback onPlayRequested;
  final VoidCallback onStopRequested;
  final VoidCallback? onGenerateSimilar;

  @override
  State<VideoCard> createState() => _VideoCardState();
}

class _VideoCardState extends State<VideoCard> {
  VideoPlayerController? _controller;
  bool _isLoading = false;

  @override
  void initState() {
    super.initState();
    if (widget.isActive) {
      WidgetsBinding.instance.addPostFrameCallback((_) => _loadAndPlay());
    }
  }

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

  @override
  void didUpdateWidget(covariant VideoCard oldWidget) {
    super.didUpdateWidget(oldWidget);
    if (oldWidget.isActive && !widget.isActive) {
      _stop();
    } else if (!oldWidget.isActive && widget.isActive) {
      _loadAndPlay();
    }
  }

  void _stop() {
    _controller?.removeListener(_onVideoUpdate);
    _controller?.pause();
    if (mounted) {
      setState(() => _isLoading = false);
    }
  }

  void _disposeController() {
    _controller?.removeListener(_onVideoUpdate);
    _controller?.dispose();
    _controller = null;
  }

  Future<void> _loadAndPlay() async {
    if (widget.videoUrl == null || widget.videoUrl!.isEmpty) {
      widget.onStopRequested();
      return;
    }

    if (_controller != null && _controller!.value.isInitialized) {
      final needSeek = _controller!.value.position >= _controller!.value.duration &&
          _controller!.value.duration.inMilliseconds > 0;
      if (needSeek) {
        setState(() => _isLoading = true);
        await _controller!.seekTo(Duration.zero);
      }
      _controller!.addListener(_onVideoUpdate);
      await _controller!.play();
      if (mounted) setState(() => _isLoading = false);
      return;
    }

    setState(() => _isLoading = true);

    try {
      final file = await DefaultCacheManager().getSingleFile(widget.videoUrl!);
      if (!mounted || !widget.isActive) {
        setState(() => _isLoading = false);
        return;
      }
      _controller = VideoPlayerController.file(file);
      await _controller!.initialize();
      _controller!.addListener(_onVideoUpdate);
      if (mounted && widget.isActive) {
        await _controller!.play();
        setState(() => _isLoading = false);
      }
    } catch (e) {
      if (mounted) {
        _disposeController();
        setState(() => _isLoading = false);
        widget.onStopRequested();
      }
    }
  }

  void _onVideoUpdate() {
    if (_controller != null &&
        _controller!.value.position >= _controller!.value.duration &&
        _controller!.value.duration.inMilliseconds > 0) {
      _controller!.removeListener(_onVideoUpdate);
      _controller!.seekTo(Duration.zero);
      if (mounted) widget.onStopRequested();
    }
  }

  void _onPlayButtonTap() {
    if (widget.isActive) {
      widget.onStopRequested();
      _stop();
    } else {
      widget.onPlayRequested();
    }
  }

  bool get _isPlaying =>
      widget.isActive && _controller != null && _controller!.value.isPlaying;

  @override
  Widget build(BuildContext context) {
    final showVideo = widget.isActive && _controller != null && _controller!.value.isInitialized;
    final showLoading = widget.isActive && _isLoading;

    return LayoutBuilder(
      builder: (context, constraints) {
        return Container(
          width: constraints.maxWidth,
          height: constraints.maxHeight,
          decoration: BoxDecoration(
            color: AppColors.surfaceAlt,
            borderRadius: BorderRadius.circular(24),
            border: Border.all(color: AppColors.border, width: 1),
            boxShadow: [
              BoxShadow(
                color: AppColors.shadowMedium,
                blurRadius: 12,
                offset: const Offset(0, 4),
              ),
            ],
          ),
          child: ClipRRect(
            borderRadius: BorderRadius.circular(24),
            child: Stack(
              fit: StackFit.expand,
              children: [
                if (showVideo)
                  Positioned.fill(
                    child: FittedBox(
                      fit: BoxFit.cover,
                      child: SizedBox(
                        width: _controller!.value.size.width > 0
                            ? _controller!.value.size.width
                            : 16,
                        height: _controller!.value.size.height > 0
                            ? _controller!.value.size.height
                            : 9,
                        child: VideoPlayer(_controller!),
                      ),
                    ),
                  )
                else
                  CachedNetworkImage(
                    imageUrl: widget.imageUrl,
                    fit: BoxFit.cover,
                    placeholder: (_, __) => Container(
                      color: AppColors.surfaceAlt,
                    ),
                    errorWidget: (_, __, ___) => Container(
                      color: AppColors.surfaceAlt,
                    ),
                  ),
                Positioned(
                  top: 12,
                  right: 12,
                  child: Container(
                    padding: const EdgeInsets.symmetric(
                      horizontal: AppSpacing.md,
                      vertical: AppSpacing.xs,
                    ),
                    decoration: BoxDecoration(
                      color: AppColors.overlayDark,
                      borderRadius: BorderRadius.circular(14),
                    ),
                    child: Row(
                      mainAxisSize: MainAxisSize.min,
                      children: [
                        Icon(
                          LucideIcons.sparkles,
                          size: 12,
                          color: AppColors.surface,
                        ),
                        const SizedBox(width: AppSpacing.sm),
                        Text(
                          widget.credits,
                          style: const TextStyle(
                            color: AppColors.surface,
                            fontSize: 11,
                            fontWeight: FontWeight.w600,
                            fontFamily: 'Inter',
                          ),
                        ),
                      ],
                    ),
                  ),
                ),
                Positioned.fill(
                  child: Center(
                    child: GestureDetector(
                      onTap: widget.videoUrl != null && widget.videoUrl!.isNotEmpty
                          ? _onPlayButtonTap
                          : null,
                      child: Container(
                        width: 48,
                        height: 48,
                        decoration: BoxDecoration(
                          color: AppColors.surface.withValues(alpha: 0.9),
                          borderRadius: BorderRadius.circular(24),
                          boxShadow: [
                            BoxShadow(
                              color: Colors.black.withValues(alpha: 0.13),
                              blurRadius: 8,
                              offset: const Offset(0, 2),
                            ),
                          ],
                        ),
                        child: showLoading
                            ? const Padding(
                                padding: EdgeInsets.all(12),
                                child: CircularProgressIndicator(
                                  color: AppColors.textPrimary,
                                  strokeWidth: 2,
                                ),
                              )
                            : Icon(
                                _isPlaying ? LucideIcons.pause : LucideIcons.play,
                                size: 24,
                                color: AppColors.textPrimary,
                              ),
                      ),
                    ),
                  ),
                ),
                if (_isPlaying)
                  Positioned(
                    top: 8,
                    left: 8,
                    child: GestureDetector(
                      onTap: () {
                        widget.onStopRequested();
                        _stop();
                      },
                      child: Container(
                        padding: const EdgeInsets.all(6),
                        decoration: BoxDecoration(
                          color: AppColors.overlayDark,
                          borderRadius: BorderRadius.circular(20),
                        ),
                        child: const Icon(
                          LucideIcons.x,
                          size: 16,
                          color: AppColors.surface,
                        ),
                      ),
                    ),
                  ),
                Positioned(
                  bottom: 12,
                  left: 12,
                  right: 12,
                  child: GestureDetector(
                    onTap: widget.onGenerateSimilar,
                    child: Container(
                      height: 44,
                      padding: const EdgeInsets.symmetric(horizontal: 12),
                      decoration: BoxDecoration(
                        color: AppColors.primary,
                        borderRadius: BorderRadius.circular(12),
                        boxShadow: [
                          BoxShadow(
                            color: AppColors.primaryShadow.withValues(alpha: 0.25),
                            blurRadius: 6,
                            offset: const Offset(0, 2),
                          ),
                        ],
                      ),
                      alignment: Alignment.center,
                      child: const Text(
                        'Generate Similar',
                        style: TextStyle(
                          color: AppColors.surface,
                          fontSize: 12,
                          fontWeight: FontWeight.w600,
                          fontFamily: 'Inter',
                        ),
                      ),
                    ),
                  ),
                ),
              ],
            ),
          ),
        );
      },
    );
  }
}