Services: Bringup hive database service.

Signed-off-by: Manjot Sidhu <manjot.techie@gmail.com>

lib/locator.dart

@@ -9,6 +9,7 @@ import 'package:mobile_app/services/API/ib_api.dart';
 import 'package:mobile_app/services/API/projects_api.dart';
 import 'package:mobile_app/services/API/users_api.dart';
 import 'package:mobile_app/services/API/country_institute_api.dart';
+import 'package:mobile_app/services/database_service.dart';
 import 'package:mobile_app/services/dialog_service.dart';
 import 'package:mobile_app/services/API/contributors_api.dart';
 import 'package:mobile_app/services/ib_engine_service.dart';
@@ -41,10 +42,16 @@ import 'package:mobile_app/viewmodels/about/about_viewmodel.dart';
 GetIt locator = GetIt.instance;
 
 Future<void> setupLocator() async {
+  // Dialog Service
   locator.registerLazySingleton(() => DialogService());
+
+  // Local Storage Service
   var localStorageService = await LocalStorageService.getInstance();
   locator.registerSingleton<LocalStorageService>(localStorageService);
 
+  // Database Service
+  locator.registerLazySingleton<DatabaseService>(() => DatabaseServiceImpl());
+
   // API Services
   locator.registerLazySingleton<ContributorsApi>(() => HttpContributorsApi());
   locator.registerLazySingleton<UsersApi>(() => HttpUsersApi());

lib/services/database_service.dart

@@ -0,0 +1,51 @@
+import 'package:flutter/foundation.dart';
+import 'package:hive/hive.dart';
+import 'package:hive_flutter/hive_flutter.dart';
+
+enum DatabaseBox {
+  IB,
+}
+
+extension DatabaseBoxExt on DatabaseBox {
+  String get inString => describeEnum(this);
+}
+
+abstract class DatabaseService {
+  Future<void> init();
+
+  Future<T> getData<T>(DatabaseBox box, String key, {T defaultValue});
+  Future<void> setData<T>(DatabaseBox box, String key, T value);
+}
+
+class DatabaseServiceImpl implements DatabaseService {
+  @override
+  Future<void> init() async {
+    // Hive DB setup
+    await Hive.initFlutter();
+
+    // Register Adapters for Hive
+    // (TODO)
+  }
+
+  Future<Box> _openBox(DatabaseBox box) async {
+    if (Hive.isBoxOpen(box.inString)) {
+      return Hive.box(box.inString);
+    }
+
+    return await Hive.openBox(box.inString);
+  }
+
+  @override
+  Future<T> getData<T>(DatabaseBox box, String key, {T defaultValue}) async {
+    var openedBox = await _openBox(box);
+
+    return openedBox.get(key, defaultValue: defaultValue);
+  }
+
+  @override
+  Future<void> setData<T>(DatabaseBox box, String key, T value) async {
+    var openedBox = await _openBox(box);
+
+    return await openedBox.put(key, value);
+  }
+}