Update: lib/services/database_helper.dart

lib/services/database_helper.dart

@@ -3,56 +3,122 @@ import 'package:path/path.dart';
 import '../models/product.dart';
 
 class DatabaseHelper {
-  static final DatabaseHelper _instance = DatabaseHelper._internal();
   static Database? _database;
-
-  factory DatabaseHelper() {
-    return _instance;
-  }
-
-  DatabaseHelper._internal();
+  static const String tableName = 'products';
+  static const int _databaseVersion = 2; // Increased database version for schema migration
 
   Future<Database> get database async {
-    if (_database != null) {
-      return _database!;
-    }
+    if (_database != null) return _database!;
     _database = await _initDatabase();
     return _database!;
   }
 
   Future<Database> _initDatabase() async {
-    String documentsDirectory = await getDatabasesPath();
-    String path = join(documentsDirectory, 'product_database.db');
+    sqfliteFfiInit();
+    var databaseFactory = databaseFactoryFfi;
 
-    return await openDatabase(path, version: 1, onCreate: _onCreate);
+    String databasesPath = await databaseFactory.getDatabasesPath();
+    String path = join(databasesPath, 'product_database.db');
+
+    return await databaseFactory.openDatabase(
+      path,
+      options: OpenDatabaseOptions(
+        version: _databaseVersion,
+        onCreate: _onCreate,
+        onUpgrade: _onUpgrade, // Add onUpgrade for schema migration
+      ),
+    );
   }
 
   Future<void> _onCreate(Database db, int version) async {
     await db.execute('''
-      CREATE TABLE products(
+      CREATE TABLE $tableName(
         id INTEGER PRIMARY KEY AUTOINCREMENT,
         name TEXT NOT NULL,
         code TEXT NOT NULL,
-        quantity INTEGER NOT NULL,
+        description TEXT,
+        imageUrl TEXT,
+        serialNumber TEXT,
+        model TEXT,
+        tags TEXT,
         price REAL NOT NULL,
-        description TEXT
+        costPrice REAL,
+        taxRate REAL,
+        discount REAL,
+        profitMargin REAL,
+        quantity INTEGER NOT NULL,
+        unitOfMeasure TEXT,
+        location TEXT,
+        minimumStock INTEGER,
+        supplier TEXT,
+        entryDate TEXT,
+        manufactureDate TEXT,
+        expirationDate TEXT,
+        status TEXT,
+        category TEXT,
+        brand TEXT,
+        createdBy TEXT,
+        createdAt TEXT,
+        lastModifiedBy TEXT,
+        lastModifiedAt TEXT
       )
     ''');
   }
 
+  // Handle database schema upgrades
+  Future<void> _onUpgrade(Database db, int oldVersion, int newVersion) async {
+    if (oldVersion < 2) {
+      // Add new columns if upgrading from version 1 to 2
+      // This is a simplified migration. For real apps, check if columns exist before adding.
+      await db.execute('ALTER TABLE $tableName ADD COLUMN description TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN imageUrl TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN serialNumber TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN model TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN tags TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN costPrice REAL;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN taxRate REAL;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN discount REAL;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN profitMargin REAL;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN unitOfMeasure TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN location TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN minimumStock INTEGER;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN supplier TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN entryDate TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN manufactureDate TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN expirationDate TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN status TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN category TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN brand TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN createdBy TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN createdAt TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN lastModifiedBy TEXT;');
+      await db.execute('ALTER TABLE $tableName ADD COLUMN lastModifiedAt TEXT;');
+    }
+    // Add more upgrade paths for future versions if needed
+  }
+
+
   Future<int> insertProduct(Product product) async {
     final db = await database;
+    final now = DateTime.now().toIso8601String();
+    // Ensure createdAt and lastModifiedAt are set for new products
+    final productMap = product.toMap();
+    productMap['createdAt'] = now;
+    productMap['lastModifiedAt'] = now;
+    // You might want to get createdBy from a user session
+    // productMap['createdBy'] = 'current_user_id';
+    // productMap['lastModifiedBy'] = 'current_user_id';
+
     return await db.insert(
-      'products',
-      product.toMap(),
+      tableName,
+      productMap,
       conflictAlgorithm: ConflictAlgorithm.replace,
     );
   }
 
   Future<List<Product>> getProducts() async {
     final db = await database;
-    final List<Map<String, dynamic>> maps = await db.query('products');
-
+    final List<Map<String, dynamic>> maps = await db.query(tableName);
     return List.generate(maps.length, (i) {
       return Product.fromMap(maps[i]);
     });
@@ -60,9 +126,15 @@ class DatabaseHelper {
 
   Future<int> updateProduct(Product product) async {
     final db = await database;
+    final now = DateTime.now().toIso8601String();
+    final productMap = product.toMap();
+    productMap['lastModifiedAt'] = now;
+    // You might want to get lastModifiedBy from a user session
+    // productMap['lastModifiedBy'] = 'current_user_id';
+
     return await db.update(
-      'products',
-      product.toMap(),
+      tableName,
+      productMap,
       where: 'id = ?',
       whereArgs: [product.id],
     );
@@ -70,6 +142,10 @@ class DatabaseHelper {
 
   Future<int> deleteProduct(int id) async {
     final db = await database;
-    return await db.delete('products', where: 'id = ?', whereArgs: [id]);
+    return await db.delete(
+      tableName,
+      where: 'id = ?',
+      whereArgs: [id],
+    );
   }
 }