// 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/data/services/category_controller.dart';
import '../../core/theme/app_colors.dart';
import '../../core/theme/app_dimens.dart';
import '../../core/theme/app_theme.dart';
import '../../core/widgets/app_bottom_nav.dart';
import '../../core/widgets/empty_state.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';

part 'widgets/home_drama_grid.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 categories = context.watch<CategoryController>();
    final homeBanners = context.watch<CatalogController>().feed.banners;
    final allDramas = [...?widget.dramas, ...categories.visibleDramas];
    final content = SafeArea(
      bottom: !widget.embedded,
      child: Column(
        children: [
          _header(l10n),
          Expanded(child: _feed(l10n, categories, homeBanners, allDramas)),
          if (!widget.embedded) _bottomNav(l10n),
        ],
      ),
    );
    return AnnotatedRegion<SystemUiOverlayStyle>(
      value: SystemUiOverlayStyle.light,
      child: Theme(
        data: AppTheme.dark(),
        child: widget.embedded
            ? content
            : Scaffold(backgroundColor: AppColors.ink, body: content),
      ),
    );
  }

  Widget _feed(
    AppLocalizations l10n,
    CategoryController categories,
    List<FeedBanner> banners,
    List<Drama> allDramas,
  ) => CustomScrollView(
    controller: logic.scroll,
    slivers: [
      SliverToBoxAdapter(
        child: Padding(
          padding: const EdgeInsets.fromLTRB(16, 4, 16, 0),
          child: ClipRRect(
            borderRadius: BorderRadius.circular(18),
            child: _carousel(l10n, banners, allDramas),
          ),
        ),
      ),
      SliverToBoxAdapter(
        child: Padding(
          padding: const EdgeInsets.fromLTRB(16, 18, 16, 14),
          child: _categories(l10n, categories),
        ),
      ),
      _HomeDramaGrid(
        l10n: l10n,
        categories: categories,
        onOpen: (drama) => logic.openCard(
          context,
          drama,
          embedded: widget.embedded,
          onDramaSelected: widget.onDramaSelected,
          onAction: widget.onAction,
        ),
      ),
    ],
  );

  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: AppColors.cream,
                fontSize: 20,
                fontWeight: FontWeight.w800,
                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(
      active: widget.active,
      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 _categories(AppLocalizations l10n, CategoryController categories) {
    final choices = <({String code, String label})>[
      (code: CategoryController.allCode, label: l10n.all),
      (code: CategoryController.hotCode, label: l10n.hot),
      (code: CategoryController.newCode, label: l10n.newest),
      for (final category in categories.categories)
        (code: 'category-${category.id}', label: category.name),
    ];
    return SizedBox(
      key: const Key('home-category-chips'),
      height: AppDimens.tapTarget,
      child: ListView.separated(
        scrollDirection: Axis.horizontal,
        itemCount: choices.length,
        separatorBuilder: (_, _) => const SizedBox(width: 8),
        itemBuilder: (context, index) {
          final choice = choices[index];
          final selected = categories.selectedCode == choice.code;
          return Semantics(
            selected: selected,
            button: true,
            child: GestureDetector(
              behavior: HitTestBehavior.opaque,
              onTap: () => categories.selectCode(choice.code),
              child: Center(
                child: AnimatedContainer(
                  duration: const Duration(milliseconds: 180),
                  alignment: Alignment.center,
                  padding: const EdgeInsets.symmetric(horizontal: 14),
                  decoration: BoxDecoration(
                    color: selected ? AppColors.blue : AppColors.raised,
                    borderRadius: BorderRadius.circular(AppDimens.pillRadius),
                  ),
                  child: Text(
                    choice.label,
                    maxLines: 1,
                    style: TextStyle(
                      color: selected ? AppColors.onPrimary : AppColors.cream,
                      fontSize: AppDimens.body,
                      fontWeight: selected ? FontWeight.w700 : FontWeight.w500,
                      height: 1.1,
                    ),
                  ),
                ),
              ),
            ),
          );
        },
      ),
    );
  }

  Widget _bottomNav(AppLocalizations l10n) => AppBottomNav(
    items: [
      AppBottomNavItem(
        tabKey: const Key('discover-nav-home'),
        icon: Icons.play_circle_outline_rounded,
        selectedIcon: Icons.play_circle_fill_rounded,
        label: l10n.homeTab,
        onTap: () => logic.act(
          context,
          DiscoverPageAction.home,
          embedded: widget.embedded,
          onAction: widget.onAction,
        ),
      ),
      AppBottomNavItem(
        tabKey: const Key('discover-nav-current'),
        icon: Icons.explore_outlined,
        selectedIcon: Icons.explore_rounded,
        label: l10n.discoverTab,
        selected: true,
        onTap: () {},
      ),
      AppBottomNavItem(
        tabKey: const Key('discover-nav-my'),
        icon: Icons.video_library_outlined,
        selectedIcon: Icons.video_library_rounded,
        label: l10n.myTab,
        onTap: () => logic.act(
          context,
          DiscoverPageAction.my,
          embedded: widget.embedded,
          onAction: widget.onAction,
        ),
      ),
    ],
  );
}

const _coin = AppColors.gold;

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: AppColors.raised,
      shape: StadiumBorder(
        side: BorderSide(color: AppColors.gold.withValues(alpha: 0.45)),
      ),
      child: InkWell(
        customBorder: const StadiumBorder(),
        onTap: onTap,
        child: ConstrainedBox(
          constraints: const BoxConstraints(minHeight: AppDimens.tapTarget),
          child: Padding(
            padding: const EdgeInsets.symmetric(horizontal: 10),
            child: Row(
              mainAxisSize: MainAxisSize.min,
              children: [
                Icon(icon, size: 15, color: _coin),
                const SizedBox(width: 4),
                Text(
                  label,
                  maxLines: 1,
                  style: const TextStyle(
                    color: AppColors.cream,
                    fontSize: AppDimens.caption,
                    fontWeight: FontWeight.w700,
                    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),
        minimumSize: const Size(AppDimens.tapTarget, AppDimens.tapTarget),
        shape: const StadiumBorder(),
        textStyle: const TextStyle(
          fontSize: AppDimens.body,
          fontWeight: FontWeight.w600,
        ),
      ),
      child: Text(label, maxLines: 1),
    );
  }
}