Various bugfixes + refactors

lib/providers/apps_provider.dart

@@ -0,0 +1,267 @@
+// Manages state related to the list of Apps tracked by Obtainium,
+// Exposes related functions such as those used to add, remove, download, and install Apps.
+
+import 'dart:async';
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:flutter/material.dart';
+import 'package:obtainium/providers/notifications_provider.dart';
+import 'package:provider/provider.dart';
+import 'package:path_provider/path_provider.dart';
+import 'package:flutter_fgbg/flutter_fgbg.dart';
+import 'package:obtainium/providers/source_provider.dart';
+import 'package:http/http.dart';
+import 'package:install_plugin_v2/install_plugin_v2.dart';
+
+class AppInMemory {
+  late App app;
+  double? downloadProgress;
+
+  AppInMemory(this.app, this.downloadProgress);
+}
+
+class AppsProvider with ChangeNotifier {
+  // In memory App state (should always be kept in sync with local storage versions)
+  Map<String, AppInMemory> apps = {};
+  bool loadingApps = false;
+  bool gettingUpdates = false;
+
+  // Variables to keep track of the app foreground status (installs can't run in the background)
+  bool isForeground = true;
+  late Stream<FGBGType> foregroundStream;
+  late StreamSubscription<FGBGType> foregroundSubscription;
+
+  AppsProvider({bool bg = false}) {
+    // Subscribe to changes in the app foreground status
+    foregroundStream = FGBGEvents.stream.asBroadcastStream();
+    foregroundSubscription = foregroundStream.listen((event) async {
+      isForeground = event == FGBGType.foreground;
+      if (isForeground) await loadApps();
+    });
+    loadApps();
+  }
+
+  // Given an AppId, uses stored info about the app to download an APK (with user input if needed) and install it
+  // Installs can only be done in the foreground, so a notification is sent to get the user's attention if needed
+  // Returns upon successful download, regardless of installation result
+  Future<void> downloadAndInstallLatestApp(
+      String appId, BuildContext context) async {
+    var notificationsProvider = context.read<NotificationsProvider>();
+    if (apps[appId] == null) {
+      throw 'App not found';
+    }
+    String apkUrl = apps[appId]!.app.apkUrls.last;
+    if (apps[appId]!.app.apkUrls.length > 1) {
+      await showDialog(
+          context: context,
+          builder: (BuildContext ctx) {
+            return AlertDialog(
+              scrollable: true,
+              title: const Text('Pick an APK'),
+              content: Column(children: [
+                Text(
+                    '${apps[appId]!.app.name} has more than one package - pick one.'),
+                ...apps[appId]!.app.apkUrls.map((u) => ListTile(
+                    title: Text(Uri.parse(u).pathSegments.last),
+                    leading: Radio<String>(
+                        value: u,
+                        groupValue: apkUrl,
+                        onChanged: (String? val) {
+                          apkUrl = val!;
+                        })))
+              ]),
+              actions: [
+                TextButton(
+                    onPressed: () {
+                      Navigator.of(context).pop();
+                    },
+                    child: const Text('Continue'))
+              ],
+            );
+          });
+    }
+    StreamedResponse response =
+        await Client().send(Request('GET', Uri.parse(apkUrl)));
+    File downloadFile =
+        File('${(await getExternalStorageDirectory())!.path}/$appId.apk');
+    if (downloadFile.existsSync()) {
+      downloadFile.deleteSync();
+    }
+    var length = response.contentLength;
+    var received = 0;
+    var sink = downloadFile.openWrite();
+
+    await response.stream.map((s) {
+      received += s.length;
+      apps[appId]!.downloadProgress =
+          (length != null ? received / length * 100 : 30);
+      notifyListeners();
+      return s;
+    }).pipe(sink);
+
+    await sink.close();
+    apps[appId]!.downloadProgress = null;
+    notifyListeners();
+
+    if (response.statusCode != 200) {
+      downloadFile.deleteSync();
+      throw response.reasonPhrase ?? 'Unknown Error';
+    }
+
+    while (!isForeground) {
+      await notificationsProvider.notify(completeInstallationNotification,
+          cancelExisting: true);
+      if (await FGBGEvents.stream.first == FGBGType.foreground ||
+          isForeground) {
+        break;
+        // We need to wait for the App to come to the foreground to install it
+        // Can't try to call install plugin in a background isolate (may not have worked anyways) because of:
+        // https://github.com/flutter/flutter/issues/13937
+      }
+    }
+
+    // Unfortunately this 'await' does not actually wait for the APK to finish installing
+    // So we only know that the install prompt was shown, but the user could still cancel w/o us knowing
+    // This also does not use the 'session-based' installer API, so background/silent updates are impossible
+    await InstallPlugin.installApk(downloadFile.path, 'dev.imranr.obtainium');
+
+    apps[appId]!.app.installedVersion = apps[appId]!.app.latestVersion;
+    await saveApp(apps[appId]!.app);
+  }
+
+  Future<Directory> getAppsDir() async {
+    Directory appsDir = Directory(
+        '${(await getExternalStorageDirectory())?.path as String}/app_data');
+    if (!appsDir.existsSync()) {
+      appsDir.createSync();
+    }
+    return appsDir;
+  }
+
+  Future<void> deleteSavedAPKs() async {
+    (await getExternalStorageDirectory())
+        ?.listSync()
+        .where((element) => element.path.endsWith('.apk'))
+        .forEach((element) {
+      element.deleteSync();
+    });
+  }
+
+  Future<void> loadApps() async {
+    loadingApps = true;
+    notifyListeners();
+    List<FileSystemEntity> appFiles = (await getAppsDir())
+        .listSync()
+        .where((item) => item.path.toLowerCase().endsWith('.json'))
+        .toList();
+    apps.clear();
+    for (int i = 0; i < appFiles.length; i++) {
+      App app =
+          App.fromJson(jsonDecode(File(appFiles[i].path).readAsStringSync()));
+      apps.putIfAbsent(app.id, () => AppInMemory(app, null));
+    }
+    loadingApps = false;
+    notifyListeners();
+  }
+
+  Future<void> saveApp(App app) async {
+    File('${(await getAppsDir()).path}/${app.id}.json')
+        .writeAsStringSync(jsonEncode(app.toJson()));
+    apps.update(app.id, (value) => AppInMemory(app, value.downloadProgress),
+        ifAbsent: () => AppInMemory(app, null));
+    notifyListeners();
+  }
+
+  Future<void> removeApp(String appId) async {
+    File file = File('${(await getAppsDir()).path}/$appId.json');
+    if (file.existsSync()) {
+      file.deleteSync();
+    }
+    if (apps.containsKey(appId)) {
+      apps.remove(appId);
+    }
+    notifyListeners();
+  }
+
+  bool checkAppObjectForUpdate(App app) {
+    if (!apps.containsKey(app.id)) {
+      throw 'App not found';
+    }
+    return app.latestVersion != apps[app.id]?.app.installedVersion;
+  }
+
+  Future<App?> getUpdate(String appId) async {
+    App? currentApp = apps[appId]!.app;
+    App newApp = await sourceProvider().getApp(currentApp.url);
+    if (newApp.latestVersion != currentApp.latestVersion) {
+      newApp.installedVersion = currentApp.installedVersion;
+      await saveApp(newApp);
+      return newApp;
+    }
+    return null;
+  }
+
+  Future<List<App>> checkUpdates() async {
+    List<App> updates = [];
+    if (!gettingUpdates) {
+      gettingUpdates = true;
+
+      List<String> appIds = apps.keys.toList();
+      for (int i = 0; i < appIds.length; i++) {
+        App? newApp = await getUpdate(appIds[i]);
+        if (newApp != null) {
+          updates.add(newApp);
+        }
+      }
+      gettingUpdates = false;
+    }
+    return updates;
+  }
+
+  List<String> getExistingUpdates() {
+    List<String> updateAppIds = [];
+    List<String> appIds = apps.keys.toList();
+    for (int i = 0; i < appIds.length; i++) {
+      App? app = apps[appIds[i]]!.app;
+      if (app.installedVersion != app.latestVersion) {
+        updateAppIds.add(app.id);
+      }
+    }
+    return updateAppIds;
+  }
+
+  Future<String> exportApps() async {
+    Directory? exportDir = Directory('/storage/emulated/0/Download');
+    String path = 'Downloads';
+    if (!exportDir.existsSync()) {
+      exportDir = await getExternalStorageDirectory();
+      path = exportDir!.path;
+    }
+    File export = File(
+        '${exportDir.path}/obtainium-export-${DateTime.now().millisecondsSinceEpoch}.json');
+    export.writeAsStringSync(
+        jsonEncode(apps.values.map((e) => e.app.toJson()).toList()));
+    return path;
+  }
+
+  Future<int> importApps(String appsJSON) async {
+    // File picker does not work in android 13, so the user must paste the JSON directly into Obtainium to import Apps
+    List<App> importedApps = (jsonDecode(appsJSON) as List<dynamic>)
+        .map((e) => App.fromJson(e))
+        .toList();
+    for (App a in importedApps) {
+      a.installedVersion =
+          apps.containsKey(a.id) ? apps[a]?.app.installedVersion : null;
+      await saveApp(a);
+    }
+    notifyListeners();
+    return importedApps.length;
+  }
+
+  @override
+  void dispose() {
+    foregroundSubscription.cancel();
+    super.dispose();
+  }
+}