import 'dart:async';

import 'package:cached_network_image/cached_network_image.dart';
import 'package:cached_network_image_platform_interface/cached_network_image_platform_interface.dart';
import 'package:copy_with/copy_with.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flutter_staggered_grid_view/flutter_staggered_grid_view.dart';
import 'package:logging/logging.dart';
import 'package:nc_photos/account.dart';
import 'package:nc_photos/app_localizations.dart';
import 'package:nc_photos/bloc_util.dart';
import 'package:nc_photos/cache_manager_util.dart';
import 'package:nc_photos/controller/account_controller.dart';
import 'package:nc_photos/controller/account_pref_controller.dart';
import 'package:nc_photos/controller/collections_controller.dart';
import 'package:nc_photos/controller/pref_controller.dart';
import 'package:nc_photos/entity/album/provider.dart';
import 'package:nc_photos/entity/collection.dart';
import 'package:nc_photos/entity/collection/content_provider/album.dart';
import 'package:nc_photos/entity/collection/content_provider/nc_album.dart';
import 'package:nc_photos/entity/collection/util.dart' as collection_util;
import 'package:nc_photos/exception_event.dart';
import 'package:nc_photos/exception_util.dart';
import 'package:nc_photos/k.dart' as k;
import 'package:nc_photos/np_api_util.dart';
import 'package:nc_photos/platform/features.dart' as features;
import 'package:nc_photos/snack_bar_manager.dart';
import 'package:nc_photos/stream_util.dart';
import 'package:nc_photos/theme.dart';
import 'package:nc_photos/theme/dimension.dart';
import 'package:nc_photos/widget/album_importer.dart';
import 'package:nc_photos/widget/archive_browser.dart';
import 'package:nc_photos/widget/collection_browser.dart';
import 'package:nc_photos/widget/collection_grid_item.dart';
import 'package:nc_photos/widget/double_tap_exit_container/double_tap_exit_container.dart';
import 'package:nc_photos/widget/enhanced_photo_browser.dart';
import 'package:nc_photos/widget/fade_out_list.dart';
import 'package:nc_photos/widget/home_app_bar.dart';
import 'package:nc_photos/widget/map_browser.dart';
import 'package:nc_photos/widget/navigation_bar_blur_filter.dart';
import 'package:nc_photos/widget/new_collection_dialog.dart';
import 'package:nc_photos/widget/page_visibility_mixin.dart';
import 'package:nc_photos/widget/selectable_item_list.dart';
import 'package:nc_photos/widget/selection_app_bar.dart';
import 'package:nc_photos/widget/sharing_browser.dart';
import 'package:nc_photos/widget/trashbin_browser.dart';
import 'package:np_codegen/np_codegen.dart';
import 'package:np_ui/np_ui.dart';
import 'package:to_string/to_string.dart';

part 'home_collections.g.dart';
part 'home_collections/app_bar.dart';
part 'home_collections/bloc.dart';
part 'home_collections/nav_bar_buttons.dart';
part 'home_collections/navigation_bar.dart';
part 'home_collections/state_event.dart';
part 'home_collections/type.dart';
part 'home_collections/view.dart';

/// Show and manage a list of [Collection]s
class HomeCollections extends StatelessWidget {
  const HomeCollections({
    super.key,
  });

  @override
  Widget build(BuildContext context) {
    return BlocProvider(
      create: (context) => _Bloc(
        account: context.read<AccountController>().account,
        controller: context.read<AccountController>().collectionsController,
        prefController: context.read(),
      ),
      child: const _WrappedHomeCollections(),
    );
  }
}

class _WrappedHomeCollections extends StatefulWidget {
  const _WrappedHomeCollections();

  @override
  State<StatefulWidget> createState() => _WrappedHomeCollectionsState();
}

@npLog
class _WrappedHomeCollectionsState extends State<_WrappedHomeCollections>
    with RouteAware, PageVisibilityMixin {
  @override
  void initState() {
    super.initState();
    _bloc.add(const _LoadCollections());
  }

  @override
  Widget build(BuildContext context) {
    return MultiBlocListener(
      listeners: [
        _BlocListener(
          listenWhen: (previous, current) =>
              previous.collections != current.collections,
          listener: (context, state) {
            _bloc.add(_TransformItems(state.collections));
          },
        ),
        _BlocListener(
          listenWhen: (previous, current) => previous.error != current.error,
          listener: (context, state) {
            if (state.error != null && isPageVisible()) {
              SnackBarManager().showSnackBarForException(state.error!.error);
            }
          },
        ),
        _BlocListener(
          listenWhen: (previous, current) =>
              previous.removeError != current.removeError,
          listener: (context, state) {
            if (state.removeError != null && isPageVisible()) {
              SnackBarManager().showSnackBar(SnackBar(
                content:
                    Text(L10n.global().removeCollectionsFailedNotification),
                duration: k.snackBarDurationNormal,
              ));
            }
          },
        ),
      ],
      child: _BlocSelector(
        selector: (state) => state.selectedItems.isEmpty,
        builder: (context, isSelectedEmpty) => isSelectedEmpty
            ? const DoubleTapExitContainer(
                child: _BodyView(),
              )
            : PopScope(
                canPop: false,
                onPopInvoked: (_) {
                  context.addEvent(const _SetSelectedItems(items: {}));
                },
                child: const _BodyView(),
              ),
      ),
    );
  }

  late final _Bloc _bloc = context.read();
}

class _BodyView extends StatelessWidget {
  const _BodyView();

  @override
  Widget build(BuildContext context) {
    return Stack(
      children: [
        RefreshIndicator(
          onRefresh: () async {
            context.addEvent(const _ReloadCollections());
            await context.bloc.stream.first;
          },
          child: CustomScrollView(
            slivers: [
              _BlocBuilder(
                buildWhen: (previous, current) =>
                    previous.selectedItems.isEmpty !=
                    current.selectedItems.isEmpty,
                builder: (context, state) => state.selectedItems.isEmpty
                    ? const _AppBar()
                    : const _SelectionAppBar(),
              ),
              const SliverToBoxAdapter(
                child: SizedBox(height: 8),
              ),
              _BlocBuilder(
                buildWhen: (previous, current) =>
                    previous.transformedItems != current.transformedItems ||
                    previous.selectedItems != current.selectedItems,
                builder: (context, state) => SliverPadding(
                  padding: const EdgeInsets.symmetric(horizontal: 8),
                  sliver: SelectableItemList(
                    maxCrossAxisExtent: 256,
                    childBorderRadius: BorderRadius.zero,
                    indicatorAlignment: const Alignment(-.92, -.92),
                    items: state.transformedItems,
                    itemBuilder: (_, __, item) {
                      return _BlocSelector<int?>(
                        selector: (state) =>
                            state.itemCounts[item.collection.id],
                        builder: (context, itemCount) => _ItemView(
                          account: context.bloc.account,
                          item: item,
                          collectionItemCountOverride: itemCount,
                        ),
                      );
                    },
                    staggeredTileBuilder: (_, __) =>
                        const StaggeredTile.count(1, 1),
                    selectedItems: state.selectedItems,
                    onSelectionChange: (_, selected) {
                      context
                          .addEvent(_SetSelectedItems(items: selected.cast()));
                    },
                    onItemTap: (context, _, item) {
                      Navigator.of(context).pushNamed(
                        CollectionBrowser.routeName,
                        arguments: CollectionBrowserArguments(item.collection),
                      );
                    },
                  ),
                ),
              ),
              SliverToBoxAdapter(
                child: SizedBox(
                  height: AppDimension.of(context).homeBottomAppBarHeight,
                ),
              ),
            ],
          ),
        ),
        Align(
          alignment: Alignment.bottomCenter,
          child: NavigationBarBlurFilter(
            height: AppDimension.of(context).homeBottomAppBarHeight,
          ),
        ),
      ],
    );
  }
}

typedef _BlocBuilder = BlocBuilder<_Bloc, _State>;
typedef _BlocListener = BlocListener<_Bloc, _State>;
// typedef _BlocListenerT<T> = BlocListenerT<_Bloc, _State, T>;
typedef _BlocSelector<T> = BlocSelector<_Bloc, _State, T>;
typedef _Emitter = Emitter<_State>;

extension on BuildContext {
  _Bloc get bloc => read<_Bloc>();
  _State get state => bloc.state;
  void addEvent(_Event event) => bloc.add(event);
}