LWJGL3 repacker

Since the Java module system doesn't allow multiple JARs to declare the same module, it has to be packed into one in order for Forge 1.17+ to work.
By this way, Forge started working but there's no input for some reasons.

app_pojavlauncher/src/main/assets/components/lwjgl3/version

@@ -1 +1 @@
-1647645869468
+1652063179136

app_pojavlauncher/src/main/java/net/kdt/pojavlaunch/PojavLoginActivity.java

@@ -58,16 +58,22 @@ import net.kdt.pojavlaunch.value.PerVersionConfig;
 import net.kdt.pojavlaunch.value.launcherprofiles.LauncherProfiles;
 import net.kdt.pojavlaunch.value.launcherprofiles.MinecraftProfile;
 
+import org.apache.commons.compress.utils.IOUtils;
 import org.apache.commons.io.FileUtils;
 
 import java.io.BufferedReader;
 import java.io.File;
 import java.io.FileInputStream;
+import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.util.Arrays;
 import java.util.Locale;
+import java.util.jar.Attributes;
+import java.util.jar.JarEntry;
+import java.util.jar.JarInputStream;
+import java.util.jar.JarOutputStream;
 
 public class PojavLoginActivity extends BaseActivity {
     private final Object mLockStoragePerm = new Object();
@@ -261,8 +267,41 @@ public class PojavLoginActivity extends BaseActivity {
         PojavProfile.setCurrentProfile(this, null);
     }
 
+    private void repackLWJGL3(boolean ignoreExistence) throws IOException {
+        File outFile = new File(Tools.DIR_GAME_HOME + "/lwjgl3/lwjgl-fat.jar");
+        File outTmpFile = new File(Tools.DIR_GAME_HOME + "/lwjgl3/lwjgl-fat.jar.tmp");
+        File[] innerFiles = outTmpFile.getParentFile().listFiles();
 
-    private void unpackComponent(AssetManager am, String component) throws IOException {
+        if (outFile.exists() && !ignoreExistence) {
+            return;
+        }
+        outFile.delete();
+        outTmpFile.delete();
+
+        java.util.jar.Manifest manifest = new java.util.jar.Manifest();
+        manifest.getMainAttributes().put(Attributes.Name.MANIFEST_VERSION, "1.0");
+        JarOutputStream outJar = new JarOutputStream(new FileOutputStream(outTmpFile), manifest);
+        outJar.setLevel(9);
+
+        for (File file : innerFiles) {
+            if (!file.getName().endsWith(".jar")) continue;
+            JarInputStream inJar = new JarInputStream(new FileInputStream(file));
+            JarEntry entry;
+            while ((entry = inJar.getNextJarEntry()) != null) {
+                // avoid some duplicated entries
+                if (entry.getSize() == 0 || entry.getName().equals("META-INF/INDEX.LIST") || entry.getName().startsWith("META-INF/versions")) continue;
+                outJar.putNextEntry(new JarEntry(entry.getName()));
+                IOUtils.copy(inJar, outJar);
+            }
+            inJar.close();
+            file.delete();
+        }
+
+        outJar.close();
+        outTmpFile.renameTo(outFile);
+    }
+
+    private boolean unpackComponent(AssetManager am, String component) throws IOException {
         File versionFile = new File(Tools.DIR_GAME_HOME + "/" + component + "/version");
         InputStream is = am.open("components/" + component + "/version");
         if(!versionFile.exists()) {
@@ -292,8 +331,10 @@ public class PojavLoginActivity extends BaseActivity {
                 }
             } else {
                 Log.i("UnpackPrep", component + ": Pack is up-to-date with the launcher, continuing...");
+                return false;
             }
         }
+        return true;
     }
     public static void disableSplash(String dir) {
         mkdirs(dir + "/config");
@@ -340,7 +381,11 @@ public class PojavLoginActivity extends BaseActivity {
             AssetManager am = this.getAssets();
             
             unpackComponent(am, "caciocavallo");
-            unpackComponent(am, "lwjgl3");
+
+            // Since the Java module system doesn't allow multiple JARs to declare the same module,
+            // we repack them to a single file here
+            repackLWJGL3(unpackComponent(am, "lwjgl3"));
+
             if(!installRuntimeAutomatically(am,MultiRTUtils.getRuntimes().size() > 0)) {
                MultiRTConfigDialog.openRuntimeSelector(this, MultiRTConfigDialog.MULTIRT_PICK_RUNTIME_STARTUP);
                 synchronized (mLockSelectJRE) {