feat(plugins): cache available plugin list

jadx-plugins-tools/src/main/java/jadx/plugins/tools/JadxPluginsList.java

@@ -3,18 +3,22 @@ package jadx.plugins.tools;
 import java.io.InputStreamReader;
 import java.io.Reader;
 import java.lang.reflect.Type;
+import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.function.Consumer;
 
 import org.jetbrains.annotations.Nullable;
-import org.jetbrains.annotations.TestOnly;
 
 import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
 import com.google.gson.reflect.TypeToken;
 
 import jadx.api.plugins.utils.ZipSecurity;
 import jadx.core.utils.files.FileUtils;
+import jadx.plugins.tools.data.JadxPluginListCache;
 import jadx.plugins.tools.data.JadxPluginMetadata;
 import jadx.plugins.tools.resolvers.github.GithubTools;
 import jadx.plugins.tools.resolvers.github.LocationInfo;
@@ -22,6 +26,8 @@ import jadx.plugins.tools.resolvers.github.data.Asset;
 import jadx.plugins.tools.resolvers.github.data.Release;
 import jadx.plugins.tools.utils.PluginUtils;
 
+import static jadx.plugins.tools.utils.PluginFiles.PLUGINS_LIST_CACHE;
+
 /**
  * TODO: implement list caching (on disk) with check for new release
  */
@@ -31,32 +37,96 @@ public class JadxPluginsList {
 	private static final Type LIST_TYPE = new TypeToken<List<JadxPluginMetadata>>() {
 	}.getType();
 
+	private static final Type CACHE_TYPE = new TypeToken<JadxPluginListCache>() {
+	}.getType();
+
 	public static JadxPluginsList getInstance() {
 		return INSTANCE;
 	}
 
-	private @Nullable List<JadxPluginMetadata> cache;
+	private @Nullable JadxPluginListCache loadedList;
 
 	private JadxPluginsList() {
 	}
 
-	public synchronized List<JadxPluginMetadata> fetch() {
-		if (cache != null) {
-			return cache;
+	/**
+	 * List provider with update callback.
+	 * Can be called one or two times:
+	 * <br>
+	 * - Apply cached data first
+	 * <br>
+	 * - If update is available, apply data after fetch
+	 * <br>
+	 * Method call is blocking.
+	 */
+	public synchronized void get(Consumer<List<JadxPluginMetadata>> consumer) {
+		if (loadedList != null) {
+			consumer.accept(loadedList.getList());
+			return;
 		}
+		JadxPluginListCache listCache = loadCache();
+		if (listCache != null) {
+			consumer.accept(listCache.getList());
+		}
+		Release release = fetchLatestRelease();
+		if (listCache == null || !listCache.getVersion().equals(release.getName())) {
+			JadxPluginListCache updatedList = fetchBundle(release);
+			saveCache(updatedList);
+			consumer.accept(updatedList.getList());
+		}
+	}
+
+	public List<JadxPluginMetadata> get() {
+		AtomicReference<List<JadxPluginMetadata>> holder = new AtomicReference<>();
+		get(holder::set);
+		return holder.get();
+	}
+
+	private @Nullable JadxPluginListCache loadCache() {
+		if (!Files.isRegularFile(PLUGINS_LIST_CACHE)) {
+			return null;
+		}
+		try {
+			String jsonStr = FileUtils.readFile(PLUGINS_LIST_CACHE);
+			return buildGson().fromJson(jsonStr, CACHE_TYPE);
+		} catch (Exception e) {
+			return null;
+		}
+	}
+
+	private void saveCache(JadxPluginListCache listCache) {
+		try {
+			String jsonStr = buildGson().toJson(listCache, CACHE_TYPE);
+			FileUtils.writeFile(PLUGINS_LIST_CACHE, jsonStr);
+		} catch (Exception e) {
+			throw new RuntimeException("Error saving file: " + PLUGINS_LIST_CACHE, e);
+		}
+		loadedList = listCache;
+	}
+
+	private static Gson buildGson() {
+		return new GsonBuilder().setPrettyPrinting().create();
+	}
+
+	private Release fetchLatestRelease() {
 		LocationInfo latest = new LocationInfo("jadx-decompiler", "jadx-plugins-list", "list", null);
 		Release release = GithubTools.fetchRelease(latest);
 		List<Asset> assets = release.getAssets();
 		if (assets.isEmpty()) {
 			throw new RuntimeException("Release don't have assets");
 		}
-		Asset listAsset = assets.get(0);
+		return release;
+	}
+
+	private JadxPluginListCache fetchBundle(Release release) {
+		Asset listAsset = release.getAssets().get(0);
 		Path tmpListFile = FileUtils.createTempFile("list.zip");
 		PluginUtils.downloadFile(listAsset.getDownloadUrl(), tmpListFile);
 
-		List<JadxPluginMetadata> entries = loadListBundle(tmpListFile);
-		cache = entries;
-		return entries;
+		JadxPluginListCache listCache = new JadxPluginListCache();
+		listCache.setVersion(release.getName());
+		listCache.setList(loadListBundle(tmpListFile));
+		return listCache;
 	}
 
 	private static List<JadxPluginMetadata> loadListBundle(Path tmpListFile) {
@@ -73,14 +143,4 @@ public class JadxPluginsList {
 		});
 		return entries;
 	}
-
-	@TestOnly
-	public synchronized List<JadxPluginMetadata> fetchFromLocalBundle(Path bundleFile) {
-		if (cache != null) {
-			return cache;
-		}
-		List<JadxPluginMetadata> entries = loadListBundle(bundleFile);
-		cache = entries;
-		return entries;
-	}
 }

jadx-plugins-tools/src/main/java/jadx/plugins/tools/data/JadxPluginListCache.java

@@ -0,0 +1,24 @@
+package jadx.plugins.tools.data;
+
+import java.util.List;
+
+public class JadxPluginListCache {
+	private String version;
+	private List<JadxPluginMetadata> list;
+
+	public String getVersion() {
+		return version;
+	}
+
+	public void setVersion(String version) {
+		this.version = version;
+	}
+
+	public List<JadxPluginMetadata> getList() {
+		return list;
+	}
+
+	public void setList(List<JadxPluginMetadata> list) {
+		this.list = list;
+	}
+}

jadx-plugins-tools/src/main/java/jadx/plugins/tools/utils/PluginFiles.java

@@ -10,12 +10,13 @@ import static jadx.core.utils.files.FileUtils.makeDirs;
 public class PluginFiles {
 	private static final ProjectDirectories DIRS = ProjectDirectories.from("io.github", "skylot", "jadx");
 
-	public static final Path PLUGINS_DIR = Paths.get(DIRS.configDir, "plugins");
+	private static final Path PLUGINS_DIR = Paths.get(DIRS.configDir, "plugins");
 	public static final Path PLUGINS_JSON = PLUGINS_DIR.resolve("plugins.json");
 	public static final Path INSTALLED_DIR = PLUGINS_DIR.resolve("installed");
 	public static final Path DROPINS_DIR = PLUGINS_DIR.resolve("dropins");
 
-	public static final Path CACHE_DIR = Paths.get(DIRS.cacheDir);
+	private static final Path CACHE_DIR = Paths.get(DIRS.cacheDir);
+	public static final Path PLUGINS_LIST_CACHE = CACHE_DIR.resolve("plugin-list.json");
 
 	static {
 		makeDirs(INSTALLED_DIR);