import 'dart:io';
import 'dart:typed_data';

import 'package:flutter/material.dart';

import 'package:cached_network_image/cached_network_image.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:flutter_cache_manager/flutter_cache_manager.dart';
import 'package:share_plus/share_plus.dart';

import 'package:f0ckapp/models/MediaItem.dart';
import 'package:f0ckapp/widgets/VideoWidget.dart';
import 'package:f0ckapp/utils/SmartRefreshIndicator.dart';
import 'package:f0ckapp/utils/PageTransformer.dart';
import 'package:f0ckapp/providers/MediaProvider.dart';

class DetailView extends ConsumerStatefulWidget {
  final int initialItemId;

  const DetailView({super.key, required this.initialItemId});

  @override
  ConsumerState<DetailView> createState() => _DetailViewState();
}

class _DetailViewState extends ConsumerState<DetailView> {
  late PageController _pageController;
  bool isLoading = false;
  int _currentIndex = 0;

  @override
  void initState() {
    super.initState();

    final mediaState = ref.read(mediaProvider);
    final initialIndex = mediaState.mediaItems.indexWhere(
      (item) => item.id == widget.initialItemId,
    );
    _pageController = PageController(initialPage: initialIndex);
    _currentIndex = initialIndex;

    _pageController.addListener(() {
      setState(() => _currentIndex = _pageController.page?.round() ?? 0);
    });

    _preloadAdjacentMedia(initialIndex);
  }

  void _preloadAdjacentMedia(int index) async {
    final mediaState = ref.read(mediaProvider);
    if (index + 1 < mediaState.mediaItems.length) {
      final nextUrl = mediaState.mediaItems[index + 1].mediaUrl;
      if (await DefaultCacheManager().getFileFromCache(nextUrl) == null) {
        await DefaultCacheManager().downloadFile(nextUrl);
      }
    }
    if (index - 1 >= 0) {
      final prevUrl = mediaState.mediaItems[index - 1].mediaUrl;
      if (await DefaultCacheManager().getFileFromCache(prevUrl) == null) {
        await DefaultCacheManager().downloadFile(prevUrl);
      }
    }
  }

  Future<void> _loadMoreMedia() async {
    if (isLoading) return;
    setState(() => isLoading = true);

    try {
      await ref.read(mediaProvider.notifier).loadMedia();
    } catch (e) {
      _showError("Fehler beim Laden der Medien: $e");
    } finally {
      setState(() => isLoading = false);
    }
  }

  void _showError(String message) {
    if (!mounted) return;
    ScaffoldMessenger.of(context)
      ..removeCurrentSnackBar()
      ..showSnackBar(SnackBar(content: Text(message)));
  }

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

  @override
  Widget build(BuildContext context) {
    final mediaState = ref.watch(mediaProvider);
    final mediaNotifier = ref.read(mediaProvider.notifier);

    if (mediaState.mediaItems.isEmpty) {
      return Scaffold(
        appBar: AppBar(),
        body: const Center(child: CircularProgressIndicator()),
      );
    }

    return Scaffold(
      appBar: AppBar(
        centerTitle: true,
        title: Text('f0ck #${mediaState.mediaItems[_currentIndex].id}'),
        actions: [
          IconButton(
            icon: Icon(Icons.download),
            onPressed: () {
              // wip
            },
          ),
          PopupMenuButton<String>(
            onSelected: (value) async {
              final item = mediaState.mediaItems[_currentIndex];
              switch (value) {
                case 'media':
                  File file = await DefaultCacheManager().getSingleFile(
                    item.mediaUrl,
                  );
                  Uint8List bytes = await file.readAsBytes();
                  final params = ShareParams(
                    files: [XFile.fromData(bytes, mimeType: item.mime)],
                  );
                  await SharePlus.instance.share(params);
                  break;
                case 'direct_link':
                  await SharePlus.instance.share(
                    ShareParams(text: item.mediaUrl),
                  );
                  break;
                case 'post_link':
                  await SharePlus.instance.share(
                    ShareParams(text: item.postUrl),
                  );
                  break;
              }
            },
            itemBuilder: (context) => [
              PopupMenuItem(
                value: 'media',
                child: ListTile(
                  leading: const Icon(Icons.image),
                  title: const Text('Als Datei'),
                ),
              ),
              PopupMenuItem(
                value: 'direct_link',
                child: ListTile(
                  leading: const Icon(Icons.link),
                  title: const Text('Link zur Datei'),
                ),
              ),
              PopupMenuItem(
                value: 'post_link',
                child: ListTile(
                  leading: const Icon(Icons.article),
                  title: const Text('Link zum f0ck'),
                ),
              ),
            ],
            icon: const Icon(Icons.share),
          ),
        ],
      ),
      body: Stack(
        children: [
          PageTransformer(
            controller: _pageController,
            pages: mediaState.mediaItems.map((item) {
              int itemIndex = mediaState.mediaItems.indexOf(item);
              return SafeArea(
                child: SmartRefreshIndicator(
                  onRefresh: _loadMoreMedia,
                  child: _buildMediaItem(item, _currentIndex == itemIndex),
                ),
              );
            }).toList(),
          ),
        ],
      ),
      persistentFooterButtons: mediaState.tag != null
          ? [
              Center(
                child: InputChip(
                  label: Text(mediaState.tag!),
                  onDeleted: () {
                    mediaNotifier.setTag(null);
                    Navigator.pop(context);
                  },
                ),
              ),
            ]
          : null,
    );
  }

  Widget _buildMediaItem(MediaItem item, bool isActive) {
    final mediaNotifier = ref.read(mediaProvider.notifier);

    return SingleChildScrollView(
      child: Column(
        children: [
          if (item.mime.startsWith('image'))
            CachedNetworkImage(
              imageUrl: item.mediaUrl,
              fit: BoxFit.contain,
              placeholder: (context, url) => const CircularProgressIndicator(),
              errorWidget: (context, url, error) => const Icon(Icons.error),
            )
          else
            VideoWidget(details: item, isActive: isActive),
          const SizedBox(height: 10, width: double.infinity),
          Wrap(
            alignment: WrapAlignment.center,
            spacing: 5.0,
            children: item.tags.map((tag) {
              return ActionChip(
                onPressed: () {
                  if (tag.tag == 'sfw' || tag.tag == 'nsfw') return;
                  setState(() {
                    mediaNotifier.setTag(tag.tag);
                    Navigator.pop(context, true);
                  });
                },
                label: Text(tag.tag),
                backgroundColor: switch (tag.id) {
                  1 => Colors.green,
                  2 => Colors.red,
                  _ => const Color(0xFF090909),
                },
                labelStyle: const TextStyle(color: Colors.white),
              );
            }).toList(),
          ),
          const SizedBox(height: 20),
        ],
      ),
    );
  }
}