import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:intl/intl.dart';

import '../../../l10n/generated/app_localizations.dart';
import '../../household/data/household_providers.dart';
import '../../household/domain/household.dart';
import '../data/plant_diagnosis_service.dart';
import '../data/plants_provider.dart';
import 'diagnosis_sheet.dart';

/// Untersuchungs-Seite einer Pflanze: alle gespeicherten Diagnosen
/// (neueste zuerst); Antippen öffnet das volle Ergebnis, volle Mitglieder
/// können Einträge löschen.
class PlantDiagnosesScreen extends ConsumerWidget {
  const PlantDiagnosesScreen({super.key, required this.plantId});

  final String plantId;

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final l10n = AppLocalizations.of(context);
    final theme = Theme.of(context);
    final plant = ref.watch(plantByIdProvider(plantId));

    if (plant == null) {
      // Pflanze wurde gelöscht, während der Screen offen war.
      return Scaffold(appBar: AppBar(), body: const SizedBox.shrink());
    }

    final entries = ref.watch(plantDiagnosesProvider(plantId)).value ?? [];
    final canEdit = ref.watch(myRoleProvider) == HouseholdRole.member;
    final locale = Localizations.localeOf(context).toString();
    final dateFormat = DateFormat('d. MMMM y, HH:mm', locale);
    final healthyColor = theme.brightness == Brightness.dark
        ? Colors.green.shade300
        : Colors.green.shade700;

    return Scaffold(
      appBar: AppBar(
        title: Text('${l10n.diagnosisHistoryTitle} · ${plant.nickname}'),
      ),
      body: entries.isEmpty
          // Kommt nur vor, wenn hier der letzte Eintrag gelöscht wurde —
          // der Button im Detail ist bei leerer Historie deaktiviert.
          ? Center(
              child: Padding(
                padding: const EdgeInsets.all(24),
                child: Text(
                  l10n.diagnosisHistoryEmpty,
                  style: theme.textTheme.bodyLarge,
                  textAlign: TextAlign.center,
                ),
              ),
            )
          : ListView.builder(
              padding: const EdgeInsets.all(16),
              itemCount: entries.length,
              itemBuilder: (context, index) {
                final entry = entries[index];
                return ListTile(
                  leading: Icon(
                    entry.result.healthy
                        ? Icons.check_circle
                        : Icons.warning_amber_rounded,
                    color: entry.result.healthy
                        ? healthyColor
                        : theme.colorScheme.error,
                  ),
                  title: Text(
                    entry.result.summary,
                    maxLines: 2,
                    overflow: TextOverflow.ellipsis,
                  ),
                  subtitle: entry.createdAt != null
                      ? Text(dateFormat.format(entry.createdAt!))
                      : null,
                  trailing: canEdit
                      ? IconButton(
                          icon: const Icon(Icons.delete_outline),
                          tooltip: l10n.delete,
                          onPressed: () => _confirmDelete(context, ref, entry),
                        )
                      : null,
                  onTap: () => showDiagnosisSheet(
                    context,
                    result: entry.result,
                    plantNickname: plant.nickname,
                    createdAt: entry.createdAt,
                  ),
                );
              },
            ),
    );
  }

  Future<void> _confirmDelete(
    BuildContext context,
    WidgetRef ref,
    PlantDiagnosisEntry entry,
  ) async {
    final l10n = AppLocalizations.of(context);
    final locale = Localizations.localeOf(context).toString();
    final dateText = entry.createdAt != null
        ? DateFormat('d. MMMM y', locale).format(entry.createdAt!)
        : '';
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (dialogContext) => AlertDialog(
        title: Text(l10n.deleteDiagnosisQuestion(dateText)),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(dialogContext, false),
            child: Text(l10n.cancel),
          ),
          FilledButton(
            onPressed: () => Navigator.pop(dialogContext, true),
            child: Text(l10n.delete),
          ),
        ],
      ),
    );
    if (confirmed == true) {
      await ref
          .read(plantDiagnosisServiceProvider)
          .deleteDiagnosis(plantId, entry.id);
    }
  }
}