import 'package:flutter/material.dart';
import 'package:jiffy/jiffy.dart';

import '../../../state/app/infrastructure/loadableState/loadable_state.dart';
import '../../../state/app/infrastructure/loadableState/view/loadable_state_consumer.dart';
import '../../../state/app/infrastructure/utilityWidgets/bloc_module.dart';
import '../../../state/app/modules/marianumDates/bloc/marianum_dates_bloc.dart';
import '../../../state/app/modules/marianumDates/bloc/marianum_dates_event.dart';
import '../../../state/app/modules/marianumDates/bloc/marianum_dates_state.dart';
import '../../../widget/animated_time.dart';
import '../../../widget/centered_leading.dart';
import '../../../widget/debug/debug_tile.dart';
import '../../../widget/list_view_util.dart';
import '../timetable/custom_events/custom_event_edit_dialog.dart';

class MarianumDatesView extends StatelessWidget {
  const MarianumDatesView({super.key});

  @override
  Widget build(BuildContext context) => BlocModule<MarianumDatesBloc, LoadableState<MarianumDatesState>>(
    create: (context) => MarianumDatesBloc(),
    autoRebuild: true,
    child: (context, bloc, state) => Scaffold(
      appBar: AppBar(
        title: const Text('Marianum Termine'),
        actions: [
          PopupMenuButton<bool>(
            initialValue: bloc.showPastEvents(),
            icon: const Icon(Icons.history),
            itemBuilder: (context) => [true, false].map((e) => PopupMenuItem<bool>(
              value: e,
              enabled: e != bloc.showPastEvents(),
              child: Row(
                children: [
                  Icon(e ? Icons.history_outlined : Icons.history_toggle_off_outlined, color: Theme.of(context).colorScheme.onSurface),
                  const SizedBox(width: 15),
                  Text(e ? 'Alle anzeigen' : 'Nur zukünftige anzeigen'),
                ],
              ),
            )).toList(),
            onSelected: (e) => bloc.add(SetPastEventsVisible(e)),
          ),
        ],
      ),
      body: LoadableStateConsumer<MarianumDatesBloc, MarianumDatesState>(
        child: (state, loading) => ListViewUtil.fromList<MarianumDate>(bloc.getEvents(), (event) => _MarianumDateTile(event: event)),
      ),
    ),
  );
}

class _MarianumDateTile extends StatelessWidget {
  final MarianumDate event;
  const _MarianumDateTile({required this.event});

  String _formatSubtitle() {
    final start = Jiffy.parseFromDateTime(event.start);
    final end = Jiffy.parseFromDateTime(event.end);

    if (event.isAllDay) {
      // iCal end is exclusive for multi-day all-day events. The feed sets
      // DTSTART == DTEND for single-day all-day events, so only subtract a
      // day when end actually advances past start.
      final inclusiveEnd = event.end.isAfter(event.start) ? end.subtract(days: 1) : end;
      final sameAllDay = start.format(pattern: 'yyyy-MM-dd') == inclusiveEnd.format(pattern: 'yyyy-MM-dd');
      return sameAllDay
          ? '${start.format(pattern: 'dd.MM.yyyy')} · Ganztägig'
          : '${start.format(pattern: 'dd.MM.yyyy')} – ${inclusiveEnd.format(pattern: 'dd.MM.yyyy')} · Ganztägig';
    }

    final sameDay = start.format(pattern: 'yyyy-MM-dd') == end.format(pattern: 'yyyy-MM-dd');
    if (sameDay) {
      if (event.start == event.end) {
        return '${start.format(pattern: 'dd.MM.yyyy')} · ${start.format(pattern: 'HH:mm')}';
      }
      return '${start.format(pattern: 'dd.MM.yyyy')} · ${start.format(pattern: 'HH:mm')} – ${end.format(pattern: 'HH:mm')}';
    }
    return '${start.format(pattern: 'dd.MM.yyyy HH:mm')} – ${end.format(pattern: 'dd.MM.yyyy HH:mm')}';
  }

  @override
  Widget build(BuildContext context) => ListTile(
    leading: const CenteredLeading(Icon(Icons.event)),
    title: Text(event.title.isEmpty ? '(ohne Titel)' : event.title),
    subtitle: Text(_formatSubtitle()),
    onTap: () => _showDetails(context),
    trailing: IconButton(
      icon: const Icon(Icons.add_circle_outline),
      tooltip: 'In Stundenplan übernehmen',
      onPressed: () => showDialog(
        context: context,
        builder: (_) => CustomEventEditDialog(
          initialTitle: event.title,
          initialDescription: event.description,
          initialStart: event.start,
          initialEnd: event.end,
        ),
        barrierDismissible: false,
      ),
    ),
  );

  void _showDetails(BuildContext context) {
    showDialog(
      context: context,
      builder: (context) => SimpleDialog(
        title: Text(event.title.isEmpty ? '(ohne Titel)' : event.title),
        children: [
          ListTile(
            leading: const CenteredLeading(Icon(Icons.date_range_outlined)),
            title: Text(_formatSubtitle()),
          ),
          if (event.description != null && event.description!.trim().isNotEmpty)
            ListTile(
              leading: const CenteredLeading(Icon(Icons.notes_outlined)),
              title: Text(event.description!.trim()),
            ),
          Visibility(
            visible: !event.start.difference(DateTime.now()).isNegative,
            replacement: ListTile(
              leading: const CenteredLeading(Icon(Icons.content_paste_search_outlined)),
              title: Text(Jiffy.parseFromDateTime(event.start).fromNow()),
            ),
            child: ListTile(
              leading: const CenteredLeading(Icon(Icons.timer_outlined)),
              title: AnimatedTime(callback: () => event.start.difference(DateTime.now())),
              subtitle: Text(Jiffy.parseFromDateTime(event.start).fromNow()),
            ),
          ),
          DebugTile(context).jsonData(event.toJson()),
        ],
      ),
    );
  }
}