Remap transformer string literals during reobfuscation

gui/src/main/java/org/mcphackers/mcp/gui/MenuBar.java

@@ -186,7 +186,17 @@ public void reloadSide() {
 
 	public void reloadOptions() {
 		for (Map.Entry<TaskParameter, JMenuItem> entry : optionItems.entrySet()) {
-			entry.getValue().setSelected(mcp.options.getBooleanParameter(entry.getKey()));
+			TaskParameter param = entry.getKey();
+			JMenuItem item = entry.getValue();
+			if (param.type == String[].class) {
+				// "Active" for an array-valued option = at least one entry. Lets
+				// us render it as a toggle in the menu while still keeping the
+				// underlying value a comma-separated list.
+				String[] arr = mcp.options.getStringArrayParameter(param);
+				item.setSelected(arr != null && arr.length > 0);
+			} else if (param.type == Boolean.class) {
+				item.setSelected(mcp.options.getBooleanParameter(param));
+			}
 		}
 	}
 
@@ -222,6 +232,32 @@ private void initOptions() {
 						mcp.options.setParameter(param, b.isSelected());
 						mcp.options.save();
 					});
+				} else if (param.type == String[].class) {
+					// Array-valued option rendered as a checkbox: enabling it
+					// pops up the value editor; an empty/cancelled value reverts
+					// to disabled. Disabling clears the array. Lets the user
+					// toggle expensive opt-in features (like string-literal
+					// remapping for ASM/transformer code) without leaving the
+					// menu.
+					b = new JRadioButtonMenuItem();
+					translatableComponents.put(b, "task.param." + param.name);
+					optionItems.put(param, b);
+					final JRadioButtonMenuItem checkbox = (JRadioButtonMenuItem) b;
+					b.addActionListener(e -> {
+						if (checkbox.isSelected()) {
+							mcp.inputOptionsValue(param);
+							String[] result = mcp.options.getStringArrayParameter(param);
+							if (result == null || result.length == 0) {
+								// User cancelled or supplied an empty value —
+								// revert the checkbox so its visible state stays
+								// in sync with the underlying option.
+								checkbox.setSelected(false);
+							}
+						} else {
+							mcp.options.setParameter(param, new String[0]);
+							mcp.options.save();
+						}
+					});
 				} else {
 					b = new JMenuItem(param.getDesc());
 					b.addActionListener(u -> mcp.inputOptionsValue(param));

gui/src/main/java/org/mcphackers/mcp/main/MainGUI.java

@@ -46,7 +46,7 @@ public class MainGUI extends MCP {
 	public static final String[] TABS = {"task.decompile", "task.recompile", "task.reobfuscate", "task.build", "options.running"};
 	public static final TaskParameter[][] TAB_PARAMETERS = {
 			{TaskParameter.PATCHES, TaskParameter.FERNFLOWER_OPTIONS, TaskParameter.IGNORED_PACKAGES, TaskParameter.OUTPUT_SRC, TaskParameter.DECOMPILE_RESOURCES, TaskParameter.GUESS_GENERICS, TaskParameter.STRIP_GENERICS},
-			{TaskParameter.SOURCE_VERSION, TaskParameter.TARGET_VERSION, TaskParameter.JAVA_HOME, TaskParameter.JAVAC_ARGS}, {TaskParameter.OBFUSCATION, TaskParameter.SRG_OBFUSCATION, TaskParameter.EXCLUDED_CLASSES, TaskParameter.STRIP_SOURCE_FILE},
+			{TaskParameter.SOURCE_VERSION, TaskParameter.TARGET_VERSION, TaskParameter.JAVA_HOME, TaskParameter.JAVAC_ARGS}, {TaskParameter.OBFUSCATION, TaskParameter.SRG_OBFUSCATION, TaskParameter.EXCLUDED_CLASSES, TaskParameter.STRIP_SOURCE_FILE, TaskParameter.STRING_REMAP_PACKAGES},
 			{TaskParameter.FULL_BUILD}, {TaskParameter.RUN_BUILD, TaskParameter.RUN_ARGS, TaskParameter.GAME_ARGS}
 	};
 	public Theme theme = Theme.THEMES_MAP.get(UIManager.getCrossPlatformLookAndFeelClassName());
@@ -293,10 +293,26 @@ public void changeWorkingDirectory() {
 
 	public void inputOptionsValue(TaskParameter param) {
 		String s = MCP.TRANSLATOR.translateKey("options.enterValue");
+		Object initialValue;
 		if (param.type == String[].class) {
 			s = MCP.TRANSLATOR.translateKey("options.enterValues") + "\n" + MCP.TRANSLATOR.translateKey("options.enterValues.info");
+			// Default JOptionPane initial value for an array uses Object.toString
+			// which prints "[Ljava.lang.String;@<hash>" — meaningless to users
+			// and worse than an empty box. Render as the same comma-separated
+			// form the parser accepts so it round-trips cleanly.
+			String[] current = options.getStringArrayParameter(param);
+			StringBuilder b = new StringBuilder();
+			if (current != null) {
+				for (int i = 0; i < current.length; i++) {
+					if (i > 0) b.append(",");
+					b.append(Util.convertToEscapedString(current[i]));
+				}
+			}
+			initialValue = b.toString();
+		} else {
+			initialValue = Util.convertToEscapedString(String.valueOf(options.getParameter(param)));
 		}
-		String value = (String) JOptionPane.showInputDialog(frame, s, param.getDesc(), JOptionPane.PLAIN_MESSAGE, null, null, Util.convertToEscapedString(String.valueOf(options.getParameter(param))));
+		String value = (String) JOptionPane.showInputDialog(frame, s, param.getDesc(), JOptionPane.PLAIN_MESSAGE, null, null, initialValue);
 		safeSetParameter(param, value);
 		options.save();
 	}

src/main/java/org/mcphackers/mcp/tasks/TaskReobfuscate.java

@@ -18,6 +18,7 @@
 import org.mcphackers.mcp.tasks.mode.TaskParameter;
 import org.mcphackers.mcp.tools.FileUtil;
 import org.mcphackers.mcp.tools.injector.SourceFileTransformer;
+import org.mcphackers.mcp.tools.injector.StringLiteralRemapper;
 import org.mcphackers.mcp.tools.mappings.MappingUtil;
 import org.mcphackers.rdi.injector.data.ClassStorage;
 import org.mcphackers.rdi.injector.data.Mappings;
@@ -80,6 +81,16 @@ private void reobfuscate() throws IOException {
 			RDInjector injector = new RDInjector(reobfBin);
 			Mappings mappings = getMappings(injector.getStorage(), localSide);
 			if (mappings != null) {
+				// Rewrite string literals naming vanilla MCP symbols inside the
+				// configured user packages. Must run BEFORE applyMappings so we
+				// can still read deobf class names from Type LDCs and look up
+				// field/method descriptors from the (still-deobf) ClassStorage
+				// for reflection-pattern context. No-op when the parameter is
+				// empty, so standard MCP workflows are unaffected.
+				String[] stringRemapPackages = mcp.getOptions().getStringArrayParameter(TaskParameter.STRING_REMAP_PACKAGES);
+				if (stringRemapPackages != null && stringRemapPackages.length > 0) {
+					new StringLiteralRemapper(mappings, stringRemapPackages).transform(injector.getStorage());
+				}
 				injector.applyMappings(mappings);
 			}
 			if (stripSourceFile) {

src/main/java/org/mcphackers/mcp/tasks/mode/TaskParameter.java

@@ -36,7 +36,23 @@ public enum TaskParameter {
 	GUESS_GENERICS("generics", Boolean.class, false),
 	STRIP_GENERICS("stripgenerics", Boolean.class, false),
 	OUTPUT_SRC("outputsrc", Boolean.class, true),
-	STRIP_SOURCE_FILE("stripsourcefile", Boolean.class, true);
+	STRIP_SOURCE_FILE("stripsourcefile", Boolean.class, true),
+	/**
+	 * Internal package prefixes (slash form, e.g. {@code me/M41G/nclient/}) whose
+	 * compiled classes should have their string-literal references to vanilla
+	 * MCP names rewritten to the obfuscated equivalents during reobfuscation.
+	 * <p>
+	 * Required for any code that relies on string-keyed access to vanilla
+	 * symbols — ASM transformers (LDC owner/name/desc strings inside
+	 * {@code FieldInsnNode}/{@code MethodInsnNode} construction) and
+	 * reflection ({@code Class.getDeclaredField("name")},
+	 * {@code Class.getDeclaredMethod("name", ...)}). Without this rewrite
+	 * those strings still point at deobf names that no longer exist after
+	 * reobfuscation, and the code becomes a silent no-op at runtime.
+	 * <p>
+	 * Empty by default; standard MCP workflows are unaffected.
+	 */
+	STRING_REMAP_PACKAGES("stringremap", String[].class, new String[0]);
 
 	public static final TaskParameter[] VALUES = TaskParameter.values();