import 'package:clock/clock.dart';
import 'package:flutter/material.dart';
import 'package:intl/intl.dart';
import 'package:provider/provider.dart';

import '../../design/page_header.dart';
import '../../design/zen_nav_bar.dart';
import '../../design/zen_style.dart';
import '../../localization/app_localizations.dart';
import '../../player/views/summary_view.dart';
import '../../settings/settings_controller.dart';
import '../../streak/day.dart';
import '../session_repository.dart';

/// The current Mode's finished Sessions by day, the latest first; each opens
/// its summary again.
class HistoryView extends StatelessWidget {
  const HistoryView({super.key});

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    final mode = context.watch<SettingsController>().mode;
    return StreamBuilder(
      stream: context.read<SessionRepository>().watchSessions(mode),
      builder: (context, snapshot) {
        final sessions = snapshot.data ?? const [];
        if (sessions.isEmpty) {
          return ListView(
            children: [
              PageHeader(title: l10n.historyTitle),
              const SizedBox(height: 24),
              EmptyState(icon: Icons.history_rounded, title: l10n.historyEmptyTitle, body: l10n.historyEmptyBody),
            ],
          );
        }
        final today = Day.of(clock.now());
        final rows = <Widget>[PageHeader(title: l10n.historyTitle)];
        Day? shown;
        for (final session in sessions) {
          final day = Day.of(session.endedAt);
          if (day != shown) {
            shown = day;
            rows.add(_DayHeader(label: _dayLabel(l10n, day, today)));
          }
          rows.add(
            Padding(
              padding: const EdgeInsets.fromLTRB(16, 0, 16, 10),
              child: _SessionTile(session: session),
            ),
          );
        }
        return ListView(
          padding: EdgeInsets.only(bottom: ZenNavBar.height + 32 + MediaQuery.paddingOf(context).bottom),
          children: rows,
        );
      },
    );
  }

  static String _dayLabel(AppLocalizations l10n, Day day, Day today) {
    if (day == today) return l10n.historyToday;
    if (day == today.add(-1)) return l10n.historyYesterday;
    final date = day.at(0, 0);
    return day.year == today.year ? DateFormat.MMMEd().format(date) : DateFormat.yMMMEd().format(date);
  }
}

class _DayHeader extends StatelessWidget {
  const _DayHeader({required this.label});

  final String label;

  @override
  Widget build(BuildContext context) => Padding(
    padding: const EdgeInsets.fromLTRB(20, 8, 20, 8),
    child: Text(label, style: Theme.of(context).textTheme.titleSmall?.copyWith(color: ZenStyle.of(context).inkMuted)),
  );
}

class _SessionTile extends StatelessWidget {
  const _SessionTile({required this.session});

  final Session session;

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    final s = ZenStyle.of(context);
    final text = Theme.of(context).textTheme;
    final line = l10n.historySessionLine(
      DateFormat.Hm().format(session.endedAt),
      l10n.durationMinutes((session.duration.inSeconds / 60).round()),
    );
    return Card(
      child: InkWell(
        onTap: () => Navigator.of(context).pushNamed(SummaryView.routeName, arguments: session.id),
        child: Padding(
          padding: const EdgeInsets.fromLTRB(16, 14, 12, 14),
          child: Row(
            children: [
              Icon(
                session.complete ? Icons.check_circle_rounded : Icons.flag_rounded,
                color: session.complete ? s.accent : s.inkMuted,
              ),
              const SizedBox(width: 14),
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(session.planName, style: text.titleMedium, maxLines: 1, overflow: TextOverflow.ellipsis),
                    const SizedBox(height: 2),
                    Text(line, style: text.bodySmall?.copyWith(color: s.inkMuted)),
                  ],
                ),
              ),
              if (!session.complete)
                Container(
                  padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 4),
                  decoration: BoxDecoration(
                    color: s.surfaceSoft,
                    borderRadius: BorderRadius.circular(s.controlRadius.clamp(0, 12)),
                  ),
                  child: Text(l10n.historyEndedEarly, style: text.labelSmall?.copyWith(color: s.inkMuted)),
                ),
            ],
          ),
        ),
      ),
    );
  }
}