import 'package:cached_network_image/cached_network_image.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firebase_storage/firebase_storage.dart';
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'package:onsolgo/core/constants.dart';

/// Series portfolio editor: cover (same view as chapter list context) and chapter removal.
class ArtistSeriesManageScreen extends StatefulWidget {
  final DocumentSnapshot series;

  const ArtistSeriesManageScreen({super.key, required this.series});

  @override
  State<ArtistSeriesManageScreen> createState() => _ArtistSeriesManageScreenState();
}

class _ArtistSeriesManageScreenState extends State<ArtistSeriesManageScreen> {
  /// null | 'cover' | 'banner'
  String? _uploadingKind;

  Future<void> _uploadSeriesCover() async {
    final picker = ImagePicker();
    final XFile? image = await picker.pickImage(source: ImageSource.gallery, imageQuality: 70);
    if (image == null) return;
    setState(() => _uploadingKind = 'cover');
    try {
      final ref = FirebaseStorage.instance.ref().child('series_covers').child('${widget.series.id}.jpg');
      await ref.putData(await image.readAsBytes(), SettableMetadata(contentType: 'image/jpeg'));
      final url = await ref.getDownloadURL();
      await widget.series.reference.update({'coverUrl': url});
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Cover updated')));
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Cover upload failed: $e')));
      }
    } finally {
      if (mounted) setState(() => _uploadingKind = null);
    }
  }

  Future<void> _uploadSeriesBanner() async {
    final picker = ImagePicker();
    final XFile? image = await picker.pickImage(source: ImageSource.gallery, imageQuality: 72);
    if (image == null) return;
    setState(() => _uploadingKind = 'banner');
    try {
      final ref = FirebaseStorage.instance.ref().child('series_banners').child('${widget.series.id}.jpg');
      await ref.putData(await image.readAsBytes(), SettableMetadata(contentType: 'image/jpeg'));
      final url = await ref.getDownloadURL();
      await widget.series.reference.update({'bannerUrl': url});
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Banner updated')));
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Banner upload failed: $e')));
      }
    } finally {
      if (mounted) setState(() => _uploadingKind = null);
    }
  }

  Future<void> _clearBanner() async {
    final ok = await showDialog<bool>(
      context: context,
      builder: (c) => AlertDialog(
        backgroundColor: Colors.grey[900],
        title: const Text('Remove banner?', style: TextStyle(color: Colors.white)),
        content: const Text(
          'The series page will use the tall cover image at the top until you add a banner again.',
          style: TextStyle(color: Colors.white70),
        ),
        actions: [
          TextButton(onPressed: () => Navigator.pop(c, false), child: const Text('Cancel')),
          TextButton(
            onPressed: () => Navigator.pop(c, true),
            child: const Text('Remove', style: TextStyle(color: Colors.redAccent)),
          ),
        ],
      ),
    );
    if (ok != true || !mounted) return;
    try {
      await widget.series.reference.update({'bannerUrl': FieldValue.delete()});
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Banner removed')));
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Could not remove banner: $e')));
      }
    }
  }

  Future<void> _confirmDeleteChapter(DocumentSnapshot ch) async {
    final cd = ch.data() as Map<String, dynamic>;
    final numLabel = cd['chapterNumber']?.toString() ?? ch.id;
    final ok = await showDialog<bool>(
      context: context,
      builder: (c) => AlertDialog(
        backgroundColor: Colors.grey[900],
        title: const Text('Remove chapter?', style: TextStyle(color: Colors.white)),
        content: Text(
          'Delete chapter $numLabel from Firestore? This cannot be undone.',
          style: const TextStyle(color: Colors.white70),
        ),
        actions: [
          TextButton(onPressed: () => Navigator.pop(c, false), child: const Text('Cancel')),
          TextButton(
            onPressed: () => Navigator.pop(c, true),
            child: const Text('Delete', style: TextStyle(color: Colors.redAccent)),
          ),
        ],
      ),
    );
    if (ok != true || !mounted) return;
    try {
      await ch.reference.delete();
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Chapter $numLabel removed')));
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Could not delete: $e')));
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    final d = widget.series.data() as Map<String, dynamic>;
    final title = d['title']?.toString() ?? 'Series';
    final cover = d['coverUrl']?.toString() ?? '';
    final banner = d['bannerUrl']?.toString() ?? '';
    final busy = _uploadingKind != null;

    return Scaffold(
      backgroundColor: Colors.black,
      appBar: AppBar(
        backgroundColor: Colors.amber[900],
        title: Text(title.toUpperCase(), style: const TextStyle(fontSize: 14)),
      ),
      body: Stack(
        children: [
          StreamBuilder<QuerySnapshot>(
            stream: widget.series.reference.collection('chapters').orderBy('chapterNumber', descending: true).snapshots(),
            builder: (context, chSnap) {
              return CustomScrollView(
                slivers: [
                  SliverToBoxAdapter(
                    child: Padding(
                      padding: const EdgeInsets.all(16),
                      child: Column(
                        crossAxisAlignment: CrossAxisAlignment.stretch,
                        children: [
                          const Text(
                            'DETAIL PAGE BANNER',
                            style: TextStyle(fontSize: 11, color: Colors.grey, fontWeight: FontWeight.bold, letterSpacing: 1.2),
                          ),
                          const SizedBox(height: 6),
                          Text(
                            'Wide image at the top when readers open this series (library grid still uses the cover below).',
                            style: TextStyle(fontSize: 11, color: Colors.grey[600], height: 1.3),
                          ),
                          const SizedBox(height: 10),
                          ClipRRect(
                            borderRadius: BorderRadius.circular(12),
                            child: AspectRatio(
                              aspectRatio: 16 / 9,
                              child: banner.isEmpty
                                  ? Container(
                                      color: Colors.grey[850],
                                      alignment: Alignment.center,
                                      child: const Text('No banner yet', style: TextStyle(color: Colors.white38)),
                                    )
                                  : CachedNetworkImage(imageUrl: banner, fit: BoxFit.cover, alignment: Alignment.center),
                            ),
                          ),
                          const SizedBox(height: 10),
                          Row(
                            children: [
                              Expanded(
                                child: OutlinedButton.icon(
                                  onPressed: busy ? null : _uploadSeriesBanner,
                                  icon: const Icon(Icons.panorama_wide_angle_outlined, color: kOnsolGold),
                                  label: const Text('UPDATE BANNER', style: TextStyle(color: kOnsolGold)),
                                  style: OutlinedButton.styleFrom(side: const BorderSide(color: kOnsolGold)),
                                ),
                              ),
                              if (banner.isNotEmpty) ...[
                                const SizedBox(width: 8),
                                IconButton(
                                  tooltip: 'Remove banner',
                                  onPressed: busy ? null : _clearBanner,
                                  icon: const Icon(Icons.delete_outline, color: Colors.redAccent),
                                ),
                              ],
                            ],
                          ),
                          const SizedBox(height: 24),
                          const Text(
                            'LIBRARY COVER',
                            style: TextStyle(fontSize: 11, color: Colors.grey, fontWeight: FontWeight.bold, letterSpacing: 1.2),
                          ),
                          const SizedBox(height: 10),
                          ClipRRect(
                            borderRadius: BorderRadius.circular(12),
                            child: AspectRatio(
                              aspectRatio: 3 / 4,
                              child: cover.isEmpty
                                  ? Container(
                                      color: Colors.grey[850],
                                      alignment: Alignment.center,
                                      child: const Text('No cover', style: TextStyle(color: Colors.white38)),
                                    )
                                  : CachedNetworkImage(imageUrl: cover, fit: BoxFit.cover, alignment: Alignment.topCenter),
                            ),
                          ),
                          const SizedBox(height: 12),
                          OutlinedButton.icon(
                            onPressed: busy ? null : _uploadSeriesCover,
                            icon: const Icon(Icons.photo_library_outlined, color: kOnsolGold),
                            label: const Text('UPDATE SERIES COVER', style: TextStyle(color: kOnsolGold)),
                            style: OutlinedButton.styleFrom(side: const BorderSide(color: kOnsolGold)),
                          ),
                        ],
                      ),
                    ),
                  ),
                  const SliverToBoxAdapter(
                    child: Padding(
                      padding: EdgeInsets.fromLTRB(20, 0, 20, 8),
                      child: Text('CHAPTERS', style: TextStyle(fontSize: 16, fontWeight: FontWeight.bold)),
                    ),
                  ),
                  if (chSnap.hasError)
                    SliverToBoxAdapter(
                      child: Padding(
                        padding: const EdgeInsets.all(24),
                        child: Text('Error: ${chSnap.error}', style: const TextStyle(color: Colors.redAccent)),
                      ),
                    )
                  else if (!chSnap.hasData)
                    const SliverFillRemaining(
                      hasScrollBody: false,
                      child: Center(child: CircularProgressIndicator(color: kOnsolGold)),
                    )
                  else if (chSnap.data!.docs.isEmpty)
                    SliverToBoxAdapter(
                      child: Padding(
                        padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 16),
                        child: Center(child: Text('No chapters yet.', style: TextStyle(color: Colors.grey[500]))),
                      ),
                    )
                  else
                    SliverPadding(
                      padding: const EdgeInsets.fromLTRB(16, 0, 16, 24),
                      sliver: SliverList(
                        delegate: SliverChildBuilderDelegate(
                          (context, i) {
                            final ch = chSnap.data!.docs[i];
                            final cd = ch.data() as Map<String, dynamic>;
                            final thumb = cd['chapterCoverUrl']?.toString() ?? cover;
                            return Card(
                              color: Colors.grey[900],
                              margin: const EdgeInsets.only(bottom: 10),
                              child: ListTile(
                                leading: ClipRRect(
                                  borderRadius: BorderRadius.circular(4),
                                  child: thumb.isEmpty
                                      ? const SizedBox(width: 50, height: 50, child: ColoredBox(color: Colors.white10))
                                      : CachedNetworkImage(imageUrl: thumb, width: 50, height: 50, fit: BoxFit.cover),
                                ),
                                title: Text('Ch ${cd['chapterNumber']}', style: const TextStyle(color: Colors.white)),
                                trailing: IconButton(
                                  icon: const Icon(Icons.delete_outline, color: Colors.redAccent),
                                  onPressed: () => _confirmDeleteChapter(ch),
                                ),
                              ),
                            );
                          },
                          childCount: chSnap.data!.docs.length,
                        ),
                      ),
                    ),
                ],
              );
            },
          ),
          if (_uploadingKind != null)
            const Positioned(
              left: 0,
              right: 0,
              bottom: 0,
              child: LinearProgressIndicator(minHeight: 3),
            ),
        ],
      ),
    );
  }
}