import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../../../core/firebase/firebase_providers.dart';
import '../../household/data/household_providers.dart';
import '../../today/domain/due_task.dart';
import '../domain/plant.dart';

/// Firestore-Anbindung der Pflanzen:
/// households/{householdId}/plants/{plantId}

Plant _plantFromDoc(String id, Map<String, dynamic> data) {
  return Plant(
    id: id,
    nickname: data['nickname'] as String? ?? '',
    species: data['species'] as String? ?? '',
    locationId: data['locationId'] as String?,
    description: data['description'] as String? ?? '',
    careNotes: data['careNotes'] as String? ?? '',
    photoUrl: data['photoUrl'] as String?,
    wateringIntervalDays: (data['wateringIntervalDays'] as num?)?.toInt() ?? 7,
    fertilizingIntervalDays:
        (data['fertilizingIntervalDays'] as num?)?.toInt() ?? 28,
    lastWatered: (data['lastWatered'] as Timestamp?)?.toDate(),
    lastFertilized: (data['lastFertilized'] as Timestamp?)?.toDate(),
    lastWateredBy: data['lastWateredBy'] as String?,
    lastFertilizedBy: data['lastFertilizedBy'] as String?,
    repottingIntervalMonths:
        (data['repottingIntervalMonths'] as num?)?.toInt(),
    lastRepotted: (data['lastRepotted'] as Timestamp?)?.toDate(),
    lastRepottedBy: data['lastRepottedBy'] as String?,
    fitStars: (data['fitStars'] as num?)?.toInt(),
    fitReasoning: data['fitReasoning'] as String?,
    fitLocationId: data['fitLocationId'] as String?,
    fitAssessedAt: (data['fitAssessedAt'] as Timestamp?)?.toDate(),
  );
}

Map<String, dynamic> _plantToMap(Plant plant) {
  return {
    'nickname': plant.nickname,
    'species': plant.species,
    'locationId': plant.locationId,
    'description': plant.description,
    'careNotes': plant.careNotes,
    'photoUrl': plant.photoUrl,
    'wateringIntervalDays': plant.wateringIntervalDays,
    'fertilizingIntervalDays': plant.fertilizingIntervalDays,
    'lastWatered':
        plant.lastWatered != null ? Timestamp.fromDate(plant.lastWatered!) : null,
    'lastFertilized': plant.lastFertilized != null
        ? Timestamp.fromDate(plant.lastFertilized!)
        : null,
    'lastWateredBy': plant.lastWateredBy,
    'lastFertilizedBy': plant.lastFertilizedBy,
    'repottingIntervalMonths': plant.repottingIntervalMonths,
    'lastRepotted': plant.lastRepotted != null
        ? Timestamp.fromDate(plant.lastRepotted!)
        : null,
    'lastRepottedBy': plant.lastRepottedBy,
  };
}

/// Alle Pflanzen eines bestimmten Haushalts, live aus Firestore.
/// Die Tages-Checkliste nutzt das für jeden Haushalt des Nutzers.
final householdPlantsProvider =
    StreamProvider.family<List<Plant>, String>((ref, householdId) {
  return ref
      .watch(firestoreProvider)
      .collection('households')
      .doc(householdId)
      .collection('plants')
      .orderBy('nickname')
      .snapshots()
      .map((snapshot) => [
            for (final doc in snapshot.docs) _plantFromDoc(doc.id, doc.data()),
          ]);
});

/// Die Pflanzen des gerade aktiven Haushalts.
/// Leere Liste, solange kein Haushalt geladen ist (z. B. direkt nach Login).
final plantsProvider = Provider<AsyncValue<List<Plant>>>((ref) {
  final householdId = ref.watch(householdIdProvider).value;
  if (householdId == null) return const AsyncValue.data([]);
  return ref.watch(householdPlantsProvider(householdId));
});

final plantByIdProvider = Provider.family<Plant?, String>((ref, id) {
  final plants = ref.watch(plantsProvider).value ?? const [];
  for (final plant in plants) {
    if (plant.id == id) return plant;
  }
  return null;
});

class PlantRepository {
  PlantRepository(this._firestore, this._householdIdGetter, this._userLabelGetter);

  final FirebaseFirestore _firestore;
  final String? Function() _householdIdGetter;

  /// Anzeigename des angemeldeten Nutzers für "bestätigt von".
  final String? Function() _userLabelGetter;

  CollectionReference<Map<String, dynamic>> get _plants {
    final householdId = _householdIdGetter();
    if (householdId == null) {
      throw StateError('Kein Haushalt geladen – Aktion nicht möglich.');
    }
    return _firestore
        .collection('households')
        .doc(householdId)
        .collection('plants');
  }

  Future<void> addPlant(Plant plant) => _plants.add(_plantToMap(plant));

  Future<void> updatePlant(Plant plant) =>
      _plants.doc(plant.id).update(_plantToMap(plant));

  Future<void> removePlant(String plantId) => _plants.doc(plantId).delete();

  /// Bestätigt eine Aufgabe: setzt das Erledigungsdatum, wodurch sich die
  /// nächste Fälligkeit automatisch neu berechnet (Intervall-Modell).
  /// [householdId] kommt aus der Aufgabe – die Checkliste zeigt Aufgaben
  /// aus allen Haushalten, nicht nur dem aktiven.
  Future<void> confirmTask(
      String householdId, String plantId, CareTaskType type) {
    final field = switch (type) {
      CareTaskType.watering => 'lastWatered',
      CareTaskType.fertilizing => 'lastFertilized',
      CareTaskType.repotting => 'lastRepotted',
    };
    return _firestore
        .collection('households')
        .doc(householdId)
        .collection('plants')
        .doc(plantId)
        .update({
      field: Timestamp.now(),
      '${field}By': _userLabelGetter(),
    });
  }

  /// Speichert das Ergebnis einer Eignungs-Bewertung (V3, auf Abruf) für
  /// den aktuell zugeordneten Stellplatz.
  Future<void> saveFitAssessment(
    String plantId, {
    required int stars,
    required String reasoning,
    required String locationId,
  }) {
    return _plants.doc(plantId).update({
      'fitStars': stars,
      'fitReasoning': reasoning,
      'fitLocationId': locationId,
      'fitAssessedAt': Timestamp.now(),
    });
  }
}

final plantRepositoryProvider = Provider<PlantRepository>((ref) {
  return PlantRepository(
    ref.watch(firestoreProvider),
    () => ref.read(householdIdProvider).value,
    () {
      final email = ref.read(firebaseAuthProvider).currentUser?.email;
      // "chris@example.com" → "chris" als Anzeigename.
      return email?.split('@').first;
    },
  );
});