integrated with previous

lib/utils/db_helper.dart

@@ -0,0 +1,170 @@
+import 'package:flutter_map/flutter_map.dart';
+import 'package:rogapp/model/location_response.dart';
+import 'package:sqflite/sqflite.dart';
+import 'package:path/path.dart';
+import 'package:path_provider/path_provider.dart';
+import 'dart:io';
+import 'dart:convert'; // for jsonEncode
+
+class DatabaseHelper {
+  static const _databaseName = "FeatureDatabase.db";
+  static const _databaseVersion = 1;
+
+  // Singleton class
+  DatabaseHelper._();
+  static final DatabaseHelper instance = DatabaseHelper._();
+
+  Database? _database;
+  Future<Database> get database async {
+    if (_database != null) return _database!;
+    _database = await _initDatabase();
+    return _database!;
+  }
+
+  Future<Database> _initDatabase() async {
+    Directory documentsDirectory = await getApplicationDocumentsDirectory();
+    String path = join(documentsDirectory.path, _databaseName);
+    return await openDatabase(
+      path,
+      version: _databaseVersion,
+      onCreate: _onCreate,
+    );
+  }
+
+  Future<void> _onCreate(Database db, int version) async {
+    await db.execute('''
+      CREATE TABLE features (
+        id INTEGER PRIMARY KEY,
+        geometry TEXT NOT NULL,
+        properties TEXT NOT NULL,
+        type TEXT NOT NULL,
+        location_id,
+        latitude REAL NOT NULL,
+        longitude REAL NOT NULL
+      )
+      ''');
+  }
+  
+  // Database insert operation
+  Future<void> insertFeature(Map<String, dynamic> feature) async {
+    // Get a reference to the database.
+    final db = await database;
+
+    // Insert the feature into the correct table.
+    await db.insert(
+      'features',
+      feature,
+      conflictAlgorithm: ConflictAlgorithm.replace,
+    );
+  }
+  
+  // Database get operation
+  Future<List<Feature>> getFeatures() async {
+    Database db = await database;
+    final List<Map<String, dynamic>> maps = await db.query('features');
+
+    return List.generate(maps.length, (i) {
+      return Feature(
+        id: maps[i]['id'],
+        geometry: Geometry.fromMap(jsonDecode(maps[i]['geometry'])),
+        properties: Properties.fromMap(jsonDecode(maps[i]['properties'])),
+        type: maps[i]['type'],
+        location_id: Properties.fromMap(jsonDecode(maps[i]['properties'])).location_id,
+        latitude: Geometry.fromMap(jsonDecode(maps[i]['geometry'])).coordinates![0][1],
+        longitude: Geometry.fromMap(jsonDecode(maps[i]['geometry'])).coordinates![0][0]
+      );
+    });
+  }
+
+  // Database delete operation
+  Future<void> deleteFeature(int id) async {
+    Database db = await database;
+    await db.delete(
+      'features',
+      where: "id = ?",
+      whereArgs: [id],
+    );
+  }
+
+  Future<void> deleteAll() async {
+    // Get a reference to the database.
+    final db = await database;
+
+    // Delete all rows.
+    await db.rawDelete('DELETE FROM features');
+  }
+
+  // Database search by location_id
+  Future<List<Feature>> getFeatureByLocationId(int locationId) async {
+    Database db = await database;
+    final List<Map<String, dynamic>> maps = await db.query(
+      'features',
+      where: "location_id = ?",
+      whereArgs: [locationId],
+    );
+
+    return List.generate(maps.length, (i) {
+      return Feature(
+        id: maps[i]['id'],
+        geometry: Geometry.fromMap(jsonDecode(maps[i]['geometry'])),
+        properties: Properties.fromMap(jsonDecode(maps[i]['properties'])),
+        type: maps[i]['type'],
+        location_id: Properties.fromMap(jsonDecode(maps[i]['properties'])).location_id,
+        latitude: Geometry.fromMap(jsonDecode(maps[i]['geometry'])).coordinates![0][1],
+        longitude: Geometry.fromMap(jsonDecode(maps[i]['geometry'])).coordinates![0][0]
+      );
+    });
+  }
+
+  // Database search by latitude and longitude
+  Future<List<Feature>> getFeatureByLatLon(double latitude, double longitude) async {
+    Database db = await database;
+        final List<Map<String, dynamic>> maps = await db.query(
+      'features',
+      where: "latitude = ? AND longitude = ?",
+      whereArgs: [latitude, longitude],
+    );
+
+    return List.generate(maps.length, (i) {
+      return Feature(
+        id: maps[i]['id'],
+        geometry: Geometry.fromMap(jsonDecode(maps[i]['geometry'])),
+        properties: Properties.fromMap(jsonDecode(maps[i]['properties'])),
+        type: maps[i]['type'],
+        location_id: Properties.fromMap(jsonDecode(maps[i]['properties'])).location_id,
+        latitude: Geometry.fromMap(jsonDecode(maps[i]['geometry'])).coordinates![0][1],
+        longitude: Geometry.fromMap(jsonDecode(maps[i]['geometry'])).coordinates![0][0]
+      );
+    });
+  }
+
+  Future<List<Feature>> getFeaturesWithinBounds(LatLngBounds bounds) async {
+    final db = await database;
+
+    final List<Map<String, dynamic>> maps = await db.query(
+      'features',
+      where: 'latitude BETWEEN ? AND ? AND longitude BETWEEN ? AND ?',
+      whereArgs: [
+        bounds.southWest!.latitude,
+        bounds.northEast!.latitude,
+        bounds.southWest!.longitude,
+        bounds.northEast!.longitude,
+      ],
+    );
+
+    return List.generate(maps.length, (i) {
+      return Feature(
+        id: maps[i]['id'],
+        geometry: Geometry.fromMap(jsonDecode(maps[i]['geometry'])),
+        properties: Properties.fromMap(jsonDecode(maps[i]['properties'])),
+        type: maps[i]['type'],
+        location_id: Properties.fromMap(jsonDecode(maps[i]['properties'])).location_id,
+        latitude: Geometry.fromMap(jsonDecode(maps[i]['geometry'])).coordinates![0][1],
+        longitude: Geometry.fromMap(jsonDecode(maps[i]['geometry'])).coordinates![0][0]
+      );
+    });
+  }
+
+
+
+}