// Author: fruit.com.cn

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:provider/provider.dart';

import '../../core/data/models/drama.dart';
import '../../core/data/models/home_feed.dart';
import '../../core/data/repositories/watch_history_repository.dart';
import '../../core/data/services/catalog_controller.dart';
import '../../core/theme/app_colors.dart';
import '../../core/widgets/remote_image.dart';
import '../../l10n/app_localizations.dart';
import 'discover_binding.dart';
import 'discover_logic.dart';
import 'widgets/cover_carousel.dart';

class DiscoverPage extends StatefulWidget {
  const DiscoverPage({
    super.key,
    required this.drama,
    required this.duration,
    this.focusSearch = false,
    this.history,
    this.embedded = false,
    this.active = true,
    this.searchRequest = 0,
    this.signedIn = false,
    this.onSignIn,
    this.onCoins,
    this.onRewards,
    this.onAction,
    this.dramas,
    this.onDramaSelected,
  });

  final Drama drama;
  final Duration duration;
  final bool focusSearch;
  final WatchHistoryRepository? history;
  final bool embedded;
  final bool active;
  final int searchRequest;
  final bool signedIn;
  final VoidCallback? onSignIn;
  final VoidCallback? onCoins;
  final VoidCallback? onRewards;
  final ValueChanged<DiscoverPageAction>? onAction;
  final List<Drama>? dramas;
  final ValueChanged<Drama>? onDramaSelected;

  @override
  State<DiscoverPage> createState() => _DiscoverPageState();
}

class _DiscoverPageState extends State<DiscoverPage> {
  late final DiscoverLogic logic;

  @override
  void initState() {
    super.initState();
    logic = DiscoverBinding().create(
      drama: widget.drama,
      history: widget.history ?? context.read<WatchHistoryRepository>(),
    );
    if (widget.focusSearch) logic.searchOpen = true;
  }

  @override
  void didUpdateWidget(covariant DiscoverPage oldWidget) {
    super.didUpdateWidget(oldWidget);
    logic.syncDrama(
      active: widget.active,
      wasActive: oldWidget.active,
      nextDrama: widget.drama,
      dramaChanged: oldWidget.drama.id != widget.drama.id,
      searchRequest: widget.searchRequest,
      previousSearchRequest: oldWidget.searchRequest,
      isActive: () => mounted && widget.active,
    );
  }

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

  @override
  Widget build(BuildContext context) {
    return ListenableBuilder(
      listenable: logic,
      builder: (context, _) => _page(context),
    );
  }

  Widget _page(BuildContext context) {
    final l10n = AppLocalizations.of(context)!;
    final catalog = context.watch<CatalogController>();
    final allDramas = widget.dramas ?? [logic.drama];
    final cards = _cardsFor(
      allDramas,
      catalog.sections,
      logic.category,
      '',
    );
    final content = SafeArea(
      bottom: !widget.embedded,
      child: Column(
        children: [
          _header(l10n),
          Expanded(
            child: ListView(
              controller: logic.scroll,
              padding: const EdgeInsets.only(bottom: 24),
              children: [
                Padding(
                  padding: const EdgeInsets.fromLTRB(16, 4, 16, 0),
                  child: ClipRRect(
                    borderRadius: BorderRadius.circular(18),
                    child: _carousel(l10n, catalog.banners, allDramas),
                  ),
                ),
                Padding(
                  padding: const EdgeInsets.fromLTRB(16, 18, 16, 0),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      _categories(l10n),
                      const SizedBox(height: 18),
                      _continueHeader(l10n),
                      const SizedBox(height: 12),
                      if (cards.isEmpty)
                        Padding(
                          padding: const EdgeInsets.symmetric(vertical: 24),
                          child: Text(
                            l10n.noSearchResults,
                            style: const TextStyle(color: Color(0xFFE6E1E3)),
                          ),
                        )
                      else
                        SizedBox(
                          height: 196,
                          child: ListView(
                            scrollDirection: Axis.horizontal,
                            children: [
                              for (final card in cards) ...[
                                _continueTile(l10n, card),
                                const SizedBox(width: 12),
                              ],
                            ],
                          ),
                        ),
                    ],
                  ),
                ),
              ],
            ),
          ),
          if (!widget.embedded) _bottomNav(l10n),
        ],
      ),
    );
    return AnnotatedRegion<SystemUiOverlayStyle>(
      value: SystemUiOverlayStyle.light,
      child: Theme(
        data: ThemeData.dark(useMaterial3: true),
        child: widget.embedded
            ? content
            : Scaffold(backgroundColor: const Color(0xFF0B0C10), body: content),
      ),
    );
  }

  Widget _header(AppLocalizations l10n) {
    return Padding(
      padding: const EdgeInsets.fromLTRB(16, 6, 12, 8),
      child: Row(
        children: [
          const _BrandMark(),
          const SizedBox(width: 8),
          Expanded(
            child: Text(
              l10n.appName,
              maxLines: 1,
              overflow: TextOverflow.ellipsis,
              style: const TextStyle(
                color: Colors.white,
                fontSize: 20,
                fontWeight: FontWeight.w700,
                height: 1.1,
              ),
            ),
          ),
          const SizedBox(width: 8),
          if (widget.signedIn) ...[
            _HeaderPill(
              icon: Icons.monetization_on_rounded,
              label: r'$ 0',
              onTap: widget.onCoins,
            ),
            const SizedBox(width: 8),
            _HeaderPill(
              icon: Icons.card_giftcard_rounded,
              label: l10n.rewards,
              onTap: widget.onRewards,
            ),
          ] else
            _LoginButton(label: l10n.logIn, onTap: widget.onSignIn),
        ],
      ),
    );
  }

  Widget _carousel(
    AppLocalizations l10n,
    List<FeedBanner> banners,
    List<Drama> allDramas,
  ) {
    final items = banners.where((banner) => banner.imageUrl.isNotEmpty).toList();
    if (items.isEmpty) return const SizedBox.shrink();
    return CoverCarousel(
      items: [
        for (final banner in items)
          CoverItem(
            title: _bannerTitle(banner, allDramas),
            subtitle: '',
            image: banner.imageUrl,
            onOpen: () => _openBanner(banner, allDramas),
          ),
      ],
    );
  }

  String _bannerTitle(FeedBanner banner, List<Drama> allDramas) {
    final dramaId = banner.dramaId;
    if (dramaId == null) return '';
    for (final drama in allDramas) {
      if (drama.id == dramaId) return drama.title;
    }
    return '';
  }

  void _openBanner(FeedBanner banner, List<Drama> allDramas) {
    final dramaId = banner.dramaId;
    if (dramaId == null) return;
    for (final drama in allDramas) {
      if (drama.id == dramaId) {
        logic.openCard(
          context,
          drama,
          embedded: widget.embedded,
          onDramaSelected: widget.onDramaSelected,
          onAction: widget.onAction,
        );
        return;
      }
    }
  }

  Widget _continueHeader(AppLocalizations l10n) => Row(
    children: [
      Expanded(
        child: Text(
          l10n.continueWatching,
          maxLines: 1,
          overflow: TextOverflow.ellipsis,
          style: const TextStyle(
            fontSize: 18,
            fontWeight: FontWeight.w600,
            letterSpacing: 0.2,
            height: 1.2,
          ),
        ),
      ),
      const SizedBox(width: 8),
      Text(
        l10n.seeAll,
        style: const TextStyle(
          color: AppColors.blue,
          fontSize: 13,
          fontWeight: FontWeight.w500,
        ),
      ),
    ],
  );

  Widget _continueTile(AppLocalizations l10n, _ShowcaseCard card) {
    final drama = logic.dramaFor(card.dramaId, widget.dramas ?? [logic.drama]);
    return SizedBox(
      width: 132,
      child: InkWell(
        onTap: () => logic.openCard(
          context,
          drama,
          embedded: widget.embedded,
          onDramaSelected: widget.onDramaSelected,
          onAction: widget.onAction,
        ),
        child: ClipRRect(
          borderRadius: BorderRadius.circular(14),
          child: Stack(
            fit: StackFit.expand,
            children: [
              RemoteImage(card.image),
              const DecoratedBox(
                decoration: BoxDecoration(
                  gradient: LinearGradient(
                    begin: Alignment.topCenter,
                    end: Alignment.bottomCenter,
                    colors: [Color(0x00000000), Color(0xE6000000)],
                    stops: [0.45, 1],
                  ),
                ),
              ),
              if (drama == null)
                const ColoredBox(
                  color: Color(0x99000000),
                  child: Center(
                    child: Icon(Icons.image_outlined, color: Colors.white),
                  ),
                ),
              Positioned(
                left: 10,
                right: 10,
                bottom: 10,
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      card.title,
                      maxLines: 2,
                      overflow: TextOverflow.ellipsis,
                      style: const TextStyle(
                        color: Colors.white,
                        fontSize: 13,
                        fontWeight: FontWeight.w600,
                        height: 1.2,
                      ),
                    ),
                    const SizedBox(height: 3),
                    Text(
                      drama == null ? l10n.videoPending : card.genre,
                      maxLines: 1,
                      overflow: TextOverflow.ellipsis,
                      style: const TextStyle(
                        color: Color(0xE6FFFFFF),
                        fontSize: 11,
                        fontWeight: FontWeight.w400,
                        height: 1.2,
                      ),
                    ),
                  ],
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }

  Widget _categories(AppLocalizations l10n) {
    final labels = [
      l10n.forYou,
      l10n.hot,
      l10n.newest,
      l10n.romance,
      l10n.actionGenre,
    ];
    return SizedBox(
      height: 32,
      child: ListView.separated(
        scrollDirection: Axis.horizontal,
        itemCount: labels.length,
        separatorBuilder: (_, _) => const SizedBox(width: 8),
        itemBuilder: (context, index) {
          final selected = logic.category == index;
          return GestureDetector(
            onTap: () => logic.selectCategory(index),
            child: AnimatedContainer(
              duration: const Duration(milliseconds: 180),
              alignment: Alignment.center,
              padding: const EdgeInsets.symmetric(horizontal: 12),
              decoration: BoxDecoration(
                color: selected ? AppColors.blue : const Color(0xFF1C1E24),
                borderRadius: BorderRadius.circular(16),
              ),
              child: Text(
                labels[index],
                maxLines: 1,
                style: TextStyle(
                  color: selected ? Colors.white : AppColors.muted,
                  fontSize: 13,
                  fontWeight: selected ? FontWeight.w600 : FontWeight.w500,
                  height: 1.1,
                ),
              ),
            ),
          );
        },
      ),
    );
  }

  Widget _bottomNav(AppLocalizations l10n) => Container(
    height: 63,
    decoration: const BoxDecoration(
      color: Color(0xFF0D0D11),
      border: Border(top: BorderSide(color: Color(0xFF242329))),
    ),
    child: Row(
      mainAxisAlignment: MainAxisAlignment.spaceAround,
      children: [
        _DiscoverNavItem(
          icon: Icons.play_circle_outline_rounded,
          label: l10n.homeTab,
          onTap: () => logic.act(
            context,
            DiscoverPageAction.home,
            embedded: widget.embedded,
            onAction: widget.onAction,
          ),
        ),
        _DiscoverNavItem(
          icon: Icons.explore_outlined,
          label: l10n.discoverTab,
          selected: true,
          onTap: () {},
        ),
        _DiscoverNavItem(
          icon: Icons.video_library_outlined,
          label: l10n.myTab,
          onTap: () => logic.act(
            context,
            DiscoverPageAction.my,
            embedded: widget.embedded,
            onAction: widget.onAction,
          ),
        ),
      ],
    ),
  );
}

class _DiscoverNavItem extends StatelessWidget {
  const _DiscoverNavItem({
    required this.icon,
    required this.label,
    required this.onTap,
    this.selected = false,
  });

  final IconData icon;
  final String label;
  final VoidCallback onTap;
  final bool selected;

  @override
  Widget build(BuildContext context) => InkWell(
    onTap: onTap,
    child: SizedBox(
      width: 72,
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Icon(
            icon,
            size: 21,
            color: selected ? _orange : const Color(0xFFCAC4C7),
          ),
          Text(
            label,
            style: TextStyle(
              color: selected ? _orange : const Color(0xFFCAC4C7),
              fontSize: 10,
              fontWeight: FontWeight.w700,
            ),
          ),
        ],
      ),
    ),
  );
}

class _ShowcaseCard {
  const _ShowcaseCard({
    required this.title,
    required this.genre,
    required this.image,
    this.dramaId,
  });

  final String title;
  final String genre;
  final String image;
  final String? dramaId;
}

/// 分区由服务端下发：0 为全部，其余按分区顺序对应筛选菜单（热门 / 最新 / 各分类）。
List<_ShowcaseCard> _cardsFor(
  List<Drama> dramas,
  List<FeedSection> sections,
  int category,
  String query,
) {
  final source = switch (category) {
    0 => dramas,
    _ => category < sections.length ? sections[category].dramas : const <Drama>[],
  };
  final normalized = query.trim().toLowerCase();
  return [
    for (final drama in source)
      if (normalized.isEmpty ||
          drama.title.toLowerCase().contains(normalized) ||
          drama.genre.toLowerCase().contains(normalized) ||
          drama.category.toLowerCase().contains(normalized))
        _ShowcaseCard(
          title: drama.title,
          genre: drama.genre.isEmpty ? drama.category : drama.genre,
          image: drama.posterUrl,
          dramaId: drama.id,
        ),
  ];
}

const _orange = AppColors.blue;
const _coin = Color(0xFFF5C451);

class _BrandMark extends StatelessWidget {
  const _BrandMark();

  @override
  Widget build(BuildContext context) {
    return Container(
      width: 28,
      height: 28,
      alignment: Alignment.center,
      decoration: BoxDecoration(
        color: AppColors.blue,
        borderRadius: BorderRadius.circular(8),
      ),
      child: const Icon(
        Icons.play_arrow_rounded,
        color: Colors.white,
        size: 20,
      ),
    );
  }
}

class _HeaderPill extends StatelessWidget {
  const _HeaderPill({
    required this.icon,
    required this.label,
    required this.onTap,
  });

  final IconData icon;
  final String label;
  final VoidCallback? onTap;

  @override
  Widget build(BuildContext context) {
    return Material(
      color: const Color(0xFF1C1E24),
      shape: const StadiumBorder(side: BorderSide(color: Color(0x66F5C451))),
      child: InkWell(
        customBorder: const StadiumBorder(),
        onTap: onTap,
        child: Padding(
          padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 5),
          child: Row(
            mainAxisSize: MainAxisSize.min,
            children: [
              Icon(icon, size: 15, color: _coin),
              const SizedBox(width: 4),
              Text(
                label,
                maxLines: 1,
                style: const TextStyle(
                  color: Colors.white,
                  fontSize: 12,
                  fontWeight: FontWeight.w600,
                  height: 1.1,
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

class _LoginButton extends StatelessWidget {
  const _LoginButton({required this.label, required this.onTap});

  final String label;
  final VoidCallback? onTap;

  @override
  Widget build(BuildContext context) {
    return TextButton(
      onPressed: onTap,
      style: TextButton.styleFrom(
        foregroundColor: Colors.white,
        backgroundColor: AppColors.blue,
        padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 6),
        minimumSize: Size.zero,
        tapTargetSize: MaterialTapTargetSize.shrinkWrap,
        shape: const StadiumBorder(),
        textStyle: const TextStyle(fontSize: 13, fontWeight: FontWeight.w600),
      ),
      child: Text(label, maxLines: 1),
    );
  }
}