Added updater for GitHub downloads

lib/base.dart

@@ -1,25 +1,137 @@
+// ignore_for_file: use_build_context_synchronously
+
+import 'dart:io';
+
 import 'package:flutter/material.dart';
 import 'package:animations/animations.dart';
+import 'package:install_plugin_v2/install_plugin_v2.dart';
+import 'package:permission_handler/permission_handler.dart';
 import 'package:provider/provider.dart';
+import 'package:store_checker/store_checker.dart';
 import 'package:flutter/services.dart';
+import 'package:flutter_gen/gen_l10n/app_localizations.dart';
 
 import 'package:adguard_home_manager/widgets/bottom_nav_bar.dart';
+import 'package:adguard_home_manager/widgets/update_modal.dart';
+import 'package:adguard_home_manager/widgets/download_modal.dart';
 
 import 'package:adguard_home_manager/providers/app_config_provider.dart';
+import 'package:adguard_home_manager/models/github_release.dart';
+import 'package:adguard_home_manager/constants/package_name.dart';
+import 'package:adguard_home_manager/services/http_requests.dart';
+import 'package:adguard_home_manager/functions/snackbar.dart';
 import 'package:adguard_home_manager/models/app_screen.dart';
 import 'package:adguard_home_manager/config/app_screens.dart';
 import 'package:adguard_home_manager/providers/servers_provider.dart';
 
 class Base extends StatefulWidget {
-  const Base({Key? key}) : super(key: key);
+  final AppConfigProvider appConfigProvider;
+
+  const Base({
+    Key? key,
+    required this.appConfigProvider,
+  }) : super(key: key);
 
   @override
   State<Base> createState() => _BaseState();
 }
 
-class _BaseState extends State<Base> {
+class _BaseState extends State<Base> with WidgetsBindingObserver {
   int selectedScreen = 0;
 
+  Future<GitHubRelease?> checkInstallationSource() async {
+    Source installationSource = await StoreChecker.getSource;
+    if (installationSource != Source.IS_INSTALLED_FROM_PLAY_STORE) {
+      final result = await checkAppUpdatesGitHub();
+      if (result['result'] == 'success') {
+        if (result['body'].tagName != widget.appConfigProvider.getAppInfo!.version) {
+          return result['body'];
+        }
+      }
+    }
+    return null;
+  }
+
+  Future<bool> managePermission() async {
+    try {
+      if (await Permission.storage.isGranted) {
+        return true;
+      }
+      else {
+        final PermissionStatus status = await Permission.storage.request();
+        if (status.isGranted == false) {
+          return false;
+        }
+        else {
+          return true;
+        }
+      }
+    } catch (e) {
+      return false;
+    }
+  } 
+
+  void installApk(String path) async {
+    final granted = await managePermission();
+
+    if (granted == true) {
+      path = path.replaceFirst(r'file://', '');
+
+      final file = File(path);
+      final exists = await file.exists();   
+
+      if (exists) {
+        InstallPlugin.installApk(
+          path, PackageName.packageName
+        );
+      }
+    }
+  }
+
+  @override
+  void initState() {
+    WidgetsBinding.instance.addObserver(this);
+
+    super.initState();
+    
+    WidgetsBinding.instance.addPostFrameCallback((_) async {
+      void download(String link, String version) async {
+        final granted = await managePermission();
+        if (granted == true) {
+          showDialog(
+            context: context, 
+            builder: (context) => DownloadModal(
+              url: link,
+              version: version,
+              onFinish: installApk,
+            ),
+            barrierDismissible: false
+          );
+        }
+        else {
+          showSnacbkar(
+            context: context, 
+            appConfigProvider: widget.appConfigProvider, 
+            label: AppLocalizations.of(context)!.permissionNotGranted, 
+            color: Colors.red
+          );
+        }
+      }
+
+      final result = await checkInstallationSource();
+
+      if (result != null) {
+        await showDialog(
+          context: context, 
+          builder: (context) => UpdateModal(
+            gitHubRelease: result,
+            onDownload: download,
+          ),
+        );
+      }
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
     final serversProvider = Provider.of<ServersProvider>(context);