feat: add Patcher API.

lib/models/patch.dart

@@ -0,0 +1,13 @@
+class Patch {
+  final String name;
+  final String simpleName;
+  final String version;
+  final String description;
+
+  Patch({
+    required this.name,
+    required this.simpleName,
+    required this.version,
+    required this.description,
+  });
+}

lib/services/github_api.dart

@@ -8,7 +8,13 @@ class GithubAPI {
   Future<String?> latestRelease(String org, repoName) async {
     var latestRelease = await github.repositories
         .getLatestRelease(RepositorySlug(org, repoName));
-    var dlurl = latestRelease.assets?.first.browserDownloadUrl;
+    var dlurl = latestRelease.assets
+        ?.firstWhere((asset) =>
+            asset.name != null &&
+            asset.name!.endsWith('.dex') &&
+            !asset.name!.contains('-sources') &&
+            !asset.name!.contains('-javadoc'))
+        .browserDownloadUrl;
     return dlurl;
   }
 

lib/services/patcher_api.dart

@@ -0,0 +1,100 @@
+import 'dart:io';
+import 'package:flutter/services.dart';
+import 'package:flutter_cache_manager/flutter_cache_manager.dart';
+import 'package:installed_apps/app_info.dart';
+import 'package:installed_apps/installed_apps.dart';
+import 'package:revanced_manager_flutter/models/patch.dart';
+import 'package:revanced_manager_flutter/services/github_api.dart';
+import 'package:revanced_manager_flutter/utils/string.dart';
+
+class PatcherService {
+  File? _patchBundleFile;
+  final List<AppInfo> _filteredPackages = [];
+  final Map<String, List<Patch>> _filteredPatches = <String, List<Patch>>{};
+  final GithubAPI githubAPI = GithubAPI();
+  static const platform = MethodChannel('app.revanced/patcher');
+  static final PatcherService _instance = PatcherService.internal();
+  factory PatcherService() => _instance;
+  PatcherService.internal();
+
+  Future<void> loadPatches() async {
+    if (_patchBundleFile == null) {
+      String? dexFileUrl =
+          await githubAPI.latestRelease('revanced', 'revanced-patches');
+      if (dexFileUrl != null) {
+        _patchBundleFile =
+            await DefaultCacheManager().getSingleFile(dexFileUrl);
+        try {
+          await platform.invokeMethod(
+            'loadPatches',
+            {
+              'pathBundlesPaths': <String>[_patchBundleFile!.absolute.path],
+            },
+          );
+        } on PlatformException {
+          _patchBundleFile = null;
+        }
+      }
+    }
+  }
+
+  Future<List<AppInfo>> getFilteredInstalledApps() async {
+    if (_patchBundleFile != null && _filteredPackages.isEmpty) {
+      List<AppInfo> all = await InstalledApps.getInstalledApps(false, true);
+      try {
+        List<String>? patchesPackages =
+            await platform.invokeListMethod<String>('getCompatiblePackages');
+        if (patchesPackages != null) {
+          for (AppInfo app in all) {
+            if (patchesPackages.contains(app.packageName)) {
+              _filteredPackages.add(app);
+            }
+          }
+        }
+      } on Exception {
+        return List.empty();
+      }
+    }
+    return _filteredPackages;
+  }
+
+  Future<List<Patch>?> getFilteredPatches(AppInfo? targetApp) async {
+    if (_patchBundleFile != null && targetApp != null) {
+      if (_filteredPatches[targetApp.packageName] == null ||
+          _filteredPatches[targetApp.packageName]!.isEmpty) {
+        _filteredPatches[targetApp.packageName!] = [];
+        try {
+          var patches = await platform.invokeListMethod<Map<dynamic, dynamic>>(
+            'getFilteredPatches',
+            {
+              'targetPackage': targetApp.packageName,
+              'targetVersion': targetApp.versionName,
+              'ignoreVersion': true,
+            },
+          );
+          if (patches != null) {
+            for (var patch in patches) {
+              _filteredPatches[targetApp.packageName]!.add(
+                Patch(
+                  name: patch['name'],
+                  simpleName: (patch['name'] as String)
+                      .replaceAll('-', ' ')
+                      .split('-')
+                      .join(' ')
+                      .toTitleCase(),
+                  version: patch['version'] ?? 'unknown',
+                  description: patch['description'] ?? 'unknown',
+                ),
+              );
+            }
+          }
+        } on Exception {
+          return List.empty();
+        }
+      }
+    } else {
+      return List.empty();
+    }
+    return _filteredPatches[targetApp.packageName];
+  }
+}

lib/utils/string.dart

@@ -0,0 +1,8 @@
+extension StringCasingExtension on String {
+  String toCapitalized() =>
+      length > 0 ? '${this[0].toUpperCase()}${substring(1).toLowerCase()}' : '';
+  String toTitleCase() => replaceAll(RegExp(' +'), ' ')
+      .split(' ')
+      .map((str) => str.toCapitalized())
+      .join(' ');
+}