init method

Future<void> init()

Initializes the SQLite database asynchronously.

This method is called when the instance of DatabaseWrapper is created. Since constructors cannot have await expressions, the initialization is done here. It sets the database path, ensures Flutter binding is initialized, and creates the necessary tables (if they don't already exist).

In case of future database schema upgrades, this method also handles migration between versions.

Implementation

Future<void> init() async {
  // Ensure Flutter bindings are initialized.
  WidgetsFlutterBinding.ensureInitialized();

  // Open the database and store the reference.
  database = await openDatabase(
    path.join(await getDatabasesPath(), 'engaige_meal_tracker_demo.db'),
    onCreate: (db, version) async {
      // Create the users table
      await db.execute('''
        CREATE TABLE users (
          ID INTEGER PRIMARY KEY AUTOINCREMENT,
          name TEXT NOT NULL,
          hashedPassword TEXT NULL
        )
      ''');

      // Insert the demo user directly into the database
      await db.insert('users', {
        'name': 'DemoUser123',
        'hashedPassword': '3c110c5edaf304f6ac0a678bd9766709e8654f1713bd2f6fac94f95873bd77f9a591cb9349c4f9e944a44e1ab30812e66c3f6bf6e3c566fcd4055c65de9a1245'
      });

      // Create the days table
      await db.execute('''
        CREATE TABLE days (
          ID INTEGER PRIMARY KEY AUTOINCREMENT,
          year INT NOT NULL,
          month INT NOT NULL,
          day INT NOT NULL
        )
      ''');

      // Create the meal_types table
      await db.execute('''
        CREATE TABLE meal_types (
          ID INTEGER PRIMARY KEY AUTOINCREMENT,
          name TEXT NOT NULL
        )
      ''');

      // Insert predefined meal types (breakfast, lunch, dinner, snacks)
      await db.insert('meal_types', {'name': 'breakfast'});
      await db.insert('meal_types', {'name': 'lunch'});
      await db.insert('meal_types', {'name': 'dinner'});
      await db.insert('meal_types', {'name': 'snacks'});

      // Create the meals table
      await db.execute('''
        CREATE TABLE meals (
          ID INTEGER PRIMARY KEY AUTOINCREMENT,
          fat_level INT NOT NULL,
          sugar_level INT NOT NULL
        )
      ''');

      // Create the day_meals table with composite primary key
      await db.execute('''
        CREATE TABLE day_meals (
          fk_user_id INTEGER NOT NULL,
          fk_day_id INTEGER NOT NULL,
          fk_meal_type_id INTEGER NOT NULL,
          fk_meal_id INTEGER NOT NULL,
          PRIMARY KEY (fk_user_id, fk_day_id, fk_meal_type_id),
          FOREIGN KEY (fk_user_id) REFERENCES users(ID) ON DELETE CASCADE,
          FOREIGN KEY (fk_day_id) REFERENCES days(ID) ON DELETE CASCADE,
          FOREIGN KEY (fk_meal_type_id) REFERENCES meal_types(ID) ON DELETE CASCADE,
          FOREIGN KEY (fk_meal_id) REFERENCES meals(ID) ON DELETE CASCADE
        )
      ''');
    },
    version: 1,
  );

  // Mark the database as ready.
  dbIsReady = true;
}