fix(gui): allow to select file on mapping export

jadx-gui/src/main/java/jadx/gui/settings/JadxProject.java

@@ -57,6 +57,18 @@ public JadxProject(MainWindow mainWindow) {
 		this.mainWindow = mainWindow;
 	}
 
+	public @Nullable Path getWorkingDir() {
+		if (projectPath != null) {
+			return projectPath.toAbsolutePath().getParent();
+		}
+		List<Path> files = data.getFiles();
+		if (!files.isEmpty()) {
+			Path path = files.get(0);
+			return path.toAbsolutePath().getParent();
+		}
+		return null;
+	}
+
 	@Nullable
 	public Path getProjectPath() {
 		return projectPath;
@@ -166,7 +178,7 @@ private Path buildCacheDir() {
 			Path path = files.get(0);
 			return path.resolveSibling(path.getFileName() + ".cache");
 		}
-		throw new JadxRuntimeException("Can't get working dir");
+		throw new JadxRuntimeException("Failed to build cache dir");
 	}
 
 	public boolean isEnableLiveReload() {

jadx-gui/src/main/java/jadx/gui/ui/MainWindow.java

@@ -44,6 +44,7 @@
 import javax.swing.Box;
 import javax.swing.ImageIcon;
 import javax.swing.JCheckBoxMenuItem;
+import javax.swing.JFileChooser;
 import javax.swing.JFrame;
 import javax.swing.JMenu;
 import javax.swing.JMenuBar;
@@ -85,7 +86,6 @@
 import jadx.api.ResourceFile;
 import jadx.api.plugins.utils.CommonFileUtils;
 import jadx.core.Jadx;
-import jadx.core.dex.nodes.RootNode;
 import jadx.core.utils.ListUtils;
 import jadx.core.utils.StringUtils;
 import jadx.core.utils.files.FileUtils;
@@ -362,17 +362,28 @@ private void saveProjectAs() {
 	}
 
 	private void exportMappings(MappingFormat mappingFormat) {
-		RootNode rootNode = wrapper.getDecompiler().getRoot();
-
-		Thread exportThread = new Thread(() -> {
-			new MappingExporter(rootNode).exportMappings(
-					Paths.get(project.getProjectPath().getParent().toString(),
-							"mappings" + (mappingFormat.hasSingleFile() ? "." + mappingFormat.fileExt : "")),
-					project.getCodeData(), mappingFormat);
-		});
-
-		backgroundExecutor.execute(NLS.str("progress.export_mappings"), exportThread);
-		update();
+		FileDialog fileDialog = new FileDialog(this, FileDialog.OpenMode.CUSTOM_SAVE);
+		fileDialog.setTitle(NLS.str("file.export_mappings_as"));
+		Path workingDir = project.getWorkingDir();
+		Path baseDir = workingDir != null ? workingDir : settings.getLastSaveFilePath();
+		if (mappingFormat.hasSingleFile()) {
+			fileDialog.setSelectedFile(baseDir.resolve("mappings." + mappingFormat.fileExt));
+			fileDialog.setFileExtList(Collections.singletonList(mappingFormat.fileExt));
+			fileDialog.setSelectionMode(JFileChooser.FILES_ONLY);
+		} else {
+			fileDialog.setCurrentDir(baseDir);
+			fileDialog.setSelectionMode(JFileChooser.DIRECTORIES_ONLY);
+		}
+		List<Path> paths = fileDialog.show();
+		if (paths.size() != 1) {
+			return;
+		}
+		Path savePath = paths.get(0);
+		LOG.info("Export mappings to: {}", savePath.toAbsolutePath());
+		backgroundExecutor.execute(NLS.str("progress.export_mappings"),
+				() -> new MappingExporter(wrapper.getDecompiler().getRoot())
+						.exportMappings(savePath, project.getCodeData(), mappingFormat),
+				s -> update());
 	}
 
 	void open(List<Path> paths) {

jadx-gui/src/main/java/jadx/gui/ui/dialog/FileDialog.java

@@ -27,7 +27,12 @@
 public class FileDialog {
 
 	public enum OpenMode {
-		OPEN, ADD, SAVE_PROJECT, EXPORT
+		OPEN,
+		ADD,
+		SAVE_PROJECT,
+		EXPORT,
+		CUSTOM_SAVE,
+		CUSTOM_OPEN
 	}
 
 	private final MainWindow mainWindow;
@@ -44,6 +49,26 @@ public FileDialog(MainWindow mainWindow, OpenMode mode) {
 		initForMode(mode);
 	}
 
+	public void setTitle(String title) {
+		this.title = title;
+	}
+
+	public void setFileExtList(List<String> fileExtList) {
+		this.fileExtList = fileExtList;
+	}
+
+	public void setSelectionMode(int selectionMode) {
+		this.selectionMode = selectionMode;
+	}
+
+	public void setSelectedFile(Path path) {
+		this.selectedFile = path;
+	}
+
+	public void setCurrentDir(Path currentDir) {
+		this.currentDir = currentDir;
+	}
+
 	public List<Path> show() {
 		FileChooser fileChooser = buildFileChooser();
 		int ret = isOpen ? fileChooser.showOpenDialog(mainWindow) : fileChooser.showSaveDialog(mainWindow);
@@ -66,10 +91,6 @@ public Path getCurrentDir() {
 		return currentDir;
 	}
 
-	public void setSelectedFile(Path path) {
-		this.selectedFile = path;
-	}
-
 	private void initForMode(OpenMode mode) {
 		switch (mode) {
 			case OPEN:
@@ -101,6 +122,14 @@ private void initForMode(OpenMode mode) {
 				currentDir = mainWindow.getSettings().getLastSaveFilePath();
 				isOpen = false;
 				break;
+
+			case CUSTOM_SAVE:
+				isOpen = false;
+				break;
+
+			case CUSTOM_OPEN:
+				isOpen = true;
+				break;
 		}
 	}
 
@@ -110,7 +139,7 @@ private FileChooser buildFileChooser() {
 		fileChooser.setFileSelectionMode(selectionMode);
 		fileChooser.setMultiSelectionEnabled(isOpen);
 		fileChooser.setAcceptAllFileFilterUsed(true);
-		if (!fileExtList.isEmpty()) {
+		if (Utils.notEmpty(fileExtList)) {
 			String description = NLS.str("file_dialog.supported_files") + ": (" + Utils.listToString(fileExtList) + ')';
 			fileChooser.setFileFilter(new FileNameExtensionFilter(description, fileExtList.toArray(new String[0])));
 		}