import 'package:drift/drift.dart';
import '../app_database.dart';
import '../tables.dart';

part 'mood_dao.g.dart';

// Joined result — entry + its activities
class MoodEntryWithActivities {
  final MoodEntry entry;
  final List<Activity> activities;
  final List<Tag> tags;
  MoodEntryWithActivities({
    required this.entry,
    required this.activities,
    required this.tags,
  });
}

@DriftAccessor(
    tables: [MoodEntries, EntryActivities, Activities, EntryTags, Tags])
class MoodDao extends DatabaseAccessor<AppDatabase> with _$MoodDaoMixin {
  MoodDao(super.db);

  // ── Writes ──────────────────────────────────────────────────────────────────

  Future<int> insertEntry(MoodEntriesCompanion entry) =>
      into(moodEntries).insert(entry);

  Future<void> insertEntryWithActivities({
    required MoodEntriesCompanion entry,
    required List<int> activityIds,
    required List<int> tagIds,
  }) async {
    await transaction(() async {
      final entryId = await into(moodEntries).insert(entry);
      for (final actId in activityIds) {
        await into(entryActivities).insert(
          EntryActivitiesCompanion.insert(entryId: entryId, activityId: actId),
        );
      }
      for (final tagId in tagIds) {
        await into(entryTags).insert(
          EntryTagsCompanion.insert(entryId: entryId, tagId: tagId),
        );
      }
    });
  }

  Future<void> deleteEntry(int id) =>
      (delete(moodEntries)..where((t) => t.id.equals(id))).go();

  Future<void> updateEntry(MoodEntriesCompanion entry) =>
      (update(moodEntries)..where((t) => t.id.equals(entry.id.value)))
          .write(entry);

  // ── Reads ───────────────────────────────────────────────────────────────────

  Stream<List<MoodEntry>> watchAllEntries() =>
      (select(moodEntries)..orderBy([(t) => OrderingTerm.desc(t.timestamp)]))
          .watch();

  Stream<List<MoodEntry>> watchEntriesForDay(DateTime day) {
    final start = DateTime(day.year, day.month, day.day);
    final end = start.add(const Duration(days: 1));
    return (select(moodEntries)
          ..where((t) => t.timestamp.isBetweenValues(start, end))
          ..orderBy([(t) => OrderingTerm.desc(t.timestamp)]))
        .watch();
  }

  Future<List<MoodEntry>> getEntriesInRange(DateTime start, DateTime end) =>
      (select(moodEntries)
            ..where((t) => t.timestamp.isBetweenValues(start, end))
            ..orderBy([(t) => OrderingTerm.asc(t.timestamp)]))
          .get();

  // Average mood per day — used by calendar heatmap
  Future<Map<DateTime, double>> getDailyAverages(
      DateTime start, DateTime end) async {
    final entries = await getEntriesInRange(start, end);
    final Map<DateTime, List<int>> grouped = {};
    for (final e in entries) {
      final day =
          DateTime(e.timestamp.year, e.timestamp.month, e.timestamp.day);
      grouped.putIfAbsent(day, () => []).add(e.moodLevel);
    }
    return grouped.map(
      (day, levels) =>
          MapEntry(day, levels.reduce((a, b) => a + b) / levels.length),
    );
  }
}