import 'package:drift/drift.dart';
import 'package:drift_postgres/drift_postgres.dart';
import 'package:postgres/postgres.dart' as pg;
import 'dart:io';

// Импорт конвертеров (нужен для генерации кода)
import 'converters.dart';

// Импорт всех таблиц
import 'tables/users.dart';
import 'tables/auth.dart';
import 'tables/packs.dart';
import 'tables/relations.dart';
import 'tables/subscriptions.dart';
import 'tables/payments.dart';
import 'tables/tests.dart';
import 'tables/tasks.dart';
import 'tables/promo_codes.dart';
import 'tables/discounts.dart';
import 'tables/statistics.dart';
import 'tables/telegram.dart';
import 'tables/achievements.dart';

// Импорт DAOs
import 'daos/user_dao.dart';
import 'daos/pack_dao.dart';
import 'daos/test_dao.dart';
import 'daos/payment_dao.dart';
import 'daos/subscription_dao.dart';
import 'daos/task_dao.dart';
import 'daos/promo_code_dao.dart';
import 'daos/discount_dao.dart';
import 'daos/statistics_dao.dart';
import 'daos/achievement_dao.dart';
import 'postgres_constants.dart';

// Сгенерированный код будет здесь
part 'database.g.dart';

@DriftDatabase(
  tables: [
    // User tables
    Users,
    UserDatas,
    
    // Auth tables
    Tokens,
    RefreshTokens,
    TelegramAuthCodes,
    
    // Pack tables
    CardPacks,
    GameCards,
    VoiceModels,
    
    // Relations
    UserPacks,
    PreviewCards,
    CardPackCards,
    CardVoices,
    
    // Subscription tables
    SubscriptionPlans,
    UserSubscriptions,
    
    // Payment tables
    Payments,
    
    // Test tables
    Tests,
    TestQuestions,
    TestPackRelations,
    TestStatistics,

    // Task tables
    Tasks,
    UserTasks,
    UserTaskProgresses,
    UserTaskResults,
    
    // Promo code tables
    PromoCodesCampaigns,
    PromoCodes,
    
    // Discount tables
    DiscountCampaigns,
    Discounts,
    DiscountUserDatas,
    
    // Statistics tables
    StudySessions,

    // Achievements tables
    UserAchievements,

    // Telegram tables
    ShareRequests,
  ],
  daos: [
    UserDao,
    PackDao,
    TestDao,
    PaymentDao,
    SubscriptionDao,
    TaskDao,
    PromoCodeDao,
    DiscountDao,
    StatisticsDao,
    AchievementDao,
  ],
)
class AppDatabase extends _$AppDatabase {
  AppDatabase(super.e);

  @override
  int get schemaVersion => 1;
  
  /// Factory для подключения к PostgreSQL
  static AppDatabase connect({
    required String host,
    required int port,
    required String database,
    required String username,
    required String password,
    bool useSsl = false,
  }) {
    final endpoint = pg.Endpoint(
      host: host,
      port: port,
      database: database,
      username: username,
      password: password,
    );
    
    final connection = PgDatabase(
      endpoint: endpoint,
      settings: pg.ConnectionSettings(
        sslMode: useSsl ? pg.SslMode.require : pg.SslMode.disable,
        connectTimeout: const Duration(seconds: 10),
      ),
    );
    
    return AppDatabase(connection);
  }
  
  /// Factory для подключения из environment variables
  static AppDatabase fromEnvironment() {
    return connect(
      host: Platform.environment['DB_HOST'] ?? 'localhost',
      port: int.parse(Platform.environment['DB_PORT'] ?? '5432'),
      database: Platform.environment['DB_NAME'] ?? 'mnemo_cards_dev',
      username: Platform.environment['DB_USER'] ?? 'mnemo_user',
      password: Platform.environment['DB_PASSWORD'] ?? '',
      useSsl: Platform.environment['DB_SSL_MODE'] == 'require',
    );
  }
  
  @override
  MigrationStrategy get migration => MigrationStrategy(
    onCreate: (Migrator m) async {
      print('Creating database schema...');
      await m.createAll();
      print('Database schema created successfully');
      
      // Создать индексы для оптимизации
      await _createIndexes();
    },
    onUpgrade: (Migrator m, int from, int to) async {
      print('Migrating database from version $from to $to');
      
      // Миграции при обновлении схемы
      // if (from < 2) {
      //   await m.addColumn(users, users.phoneNumber);
      // }
    },
    beforeOpen: (details) async {
      print('Opening database connection...');
      
      // Проверка подключения
      final result = await customSelect('SELECT 1 as test').getSingle();
      print('Database connection successful: ${result.data}');
      
      // Включить foreign key constraints
      await customStatement('SET CONSTRAINTS ALL IMMEDIATE');
    },
  );
  
  /// Создание индексов для оптимизации запросов
  Future<void> _createIndexes() async {
    print('Creating indexes...');
    
    // Users indexes
    await customStatement('CREATE INDEX IF NOT EXISTS idx_users_email ON users(email) WHERE email IS NOT NULL');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_users_admin ON users(admin) WHERE admin = true');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_users_not_deleted ON users(is_deleted) WHERE is_deleted = false');
    
    // UserDatas indexes
    await customStatement('CREATE INDEX IF NOT EXISTS idx_user_datas_user_id ON user_datas(user_id)');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_user_datas_last_online ON user_datas(last_time_online DESC)');
    
    // Auth indexes
    await customStatement('CREATE INDEX IF NOT EXISTS idx_tokens_user_id ON tokens(user_id)');
    // Индекс на expires без предиката (NOW() не может быть использована в предикате индекса)
    await customStatement('CREATE INDEX IF NOT EXISTS idx_tokens_expires ON tokens(expires)');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_refresh_tokens_user_id ON refresh_tokens(user_id)');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_refresh_tokens_jti ON refresh_tokens(jti)');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_refresh_tokens_not_blacklisted ON refresh_tokens(is_blacklisted) WHERE is_blacklisted = false');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_telegram_codes_code ON telegram_auth_codes(code)');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_telegram_codes_not_used ON telegram_auth_codes(is_used) WHERE is_used = false');
    
    // CardPacks indexes
    await customStatement('CREATE INDEX IF NOT EXISTS idx_packs_enabled ON card_packs(enabled) WHERE enabled = true');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_packs_order ON card_packs("order")');
    
    // GameCards indexes
    await customStatement('CREATE INDEX IF NOT EXISTS idx_cards_original ON game_cards(original)');
    
    // UserPacks indexes
    await customStatement('CREATE INDEX IF NOT EXISTS idx_user_packs_user_id ON user_packs(user_id)');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_user_packs_pack_id ON user_packs(pack_id)');
    
    // Payments indexes
    await customStatement('CREATE INDEX IF NOT EXISTS idx_payments_user_id ON payments(user_id)');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_payments_status ON payments(status)');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_payments_created ON payments(date DESC)');
    
    // Subscriptions indexes
    await customStatement('CREATE INDEX IF NOT EXISTS idx_subscriptions_user_id ON user_subscriptions(user_id)');
    // Индекс на finish без предиката (NOW() не может быть использована в предикате индекса)
    await customStatement('CREATE INDEX IF NOT EXISTS idx_subscriptions_finish ON user_subscriptions(finish)');
    
    // Tests indexes
    await customStatement('CREATE INDEX IF NOT EXISTS idx_test_questions_test_id ON test_questions(test_id)');
    
    // StudySessions indexes
    await customStatement('CREATE INDEX IF NOT EXISTS idx_sessions_user_id ON study_sessions(user_id)');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_sessions_started ON study_sessions(start_time DESC)');
    
    // PromoCodes indexes
    await customStatement('CREATE INDEX IF NOT EXISTS idx_promo_codes_code ON promo_codes(code)');
    await customStatement('CREATE INDEX IF NOT EXISTS idx_promo_codes_campaign_id ON promo_codes(campaign_id)');
    
    print('Indexes created successfully');
  }
}