fix: legacy Forge not launching

CHANGELOG.md

@@ -10,5 +10,6 @@ This changelog only contains the changes that are unreleased. For changes for in
 - Do launch checking on old Forge FML libraries and cache downloads
 
 ### Fixes
+- Legacy Forge not launching
 
 ### Misc

legacy-launch/build.gradle

@@ -0,0 +1,14 @@
+plugins {
+    id 'java'
+    id 'application'
+}
+
+sourceCompatibility = '1.8'
+targetCompatibility = '1.8'
+
+group = 'com.atlauncher'
+version = rootProject.file('src/main/resources/version').text.trim().replace('.Beta', '')
+
+application {
+    mainClass = 'com.atlauncher.mclauncher.legacy.LegacyMCLauncher'
+}

legacy-launch/src/main/java/com/atlauncher/mclauncher/legacy/LegacyMCLauncher.java

@@ -24,14 +24,12 @@ import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Modifier;
 
-import com.atlauncher.constants.Constants;
-
 public class LegacyMCLauncher {
     public static void main(String[] args) {
         String workingDirectory = args[0];
         String username = args[1];
         String session = args[2];
-        String instanceName = args[3];
+        String frameTitle = args[3];
         int screenWidth = Integer.parseInt(args[4]);
         int screenHeight = Integer.parseInt(args[5]);
         boolean maximize = Boolean.parseBoolean(args[6]);
@@ -74,7 +72,7 @@ public class LegacyMCLauncher {
             try {
                 Class<?> MCAppletClass = cl.loadClass("net.minecraft.client.MinecraftApplet");
                 Applet mcappl = (Applet) MCAppletClass.newInstance();
-                MCFrame mcWindow = new MCFrame(Constants.LAUNCHER_NAME + " - " + instanceName);
+                MCFrame mcWindow = new MCFrame(frameTitle);
                 mcWindow.start(mcappl, username, session, winSize, maximize);
             } catch (InstantiationException e) {
                 System.out.println("Applet wrapper failed! Falling back " + "to compatibility mode.");

settings.gradle

@@ -6,3 +6,4 @@
  */
 rootProject.name = name
 include('app')
+include('legacy-launch')

src/main/java/com/atlauncher/FileSystem.java

@@ -84,6 +84,21 @@ public final class FileSystem {
         renameDirectories();
 
         createDirectories();
+
+        copyResourcesOutJar();
+    }
+
+    public static void copyResourcesOutJar() throws IOException {
+        Path legacyLaunchLibrariesJar = FileSystem.LIBRARIES.resolve("launcher/legacy-launch.jar");
+
+        if (!Files.exists(legacyLaunchLibrariesJar) || Files.size(legacyLaunchLibrariesJar) != 8368l) {
+            if (!Files.isDirectory(FileSystem.LIBRARIES.resolve("launcher"))) {
+                Files.createDirectory(FileSystem.LIBRARIES.resolve("launcher"));
+            }
+
+            Files.copy(FileSystem.class.getResourceAsStream("/legacy-launch-jar"),
+                    legacyLaunchLibrariesJar, StandardCopyOption.REPLACE_EXISTING);
+        }
     }
 
     private static void deleteOldThings() throws IOException {

src/main/java/com/atlauncher/mclauncher/MCLauncher.java

@@ -19,8 +19,6 @@ package com.atlauncher.mclauncher;
 
 import java.io.File;
 import java.io.IOException;
-import java.io.UnsupportedEncodingException;
-import java.net.URLDecoder;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -44,7 +42,6 @@ import com.atlauncher.data.minecraft.LoggingClient;
 import com.atlauncher.data.minecraft.PropertyMapSerializer;
 import com.atlauncher.managers.LWJGLManager;
 import com.atlauncher.managers.LogManager;
-import com.atlauncher.mclauncher.legacy.LegacyMCLauncher;
 import com.atlauncher.network.ErrorReporting;
 import com.atlauncher.utils.Java;
 import com.atlauncher.utils.OS;
@@ -249,21 +246,18 @@ public class MCLauncher {
         }
 
         if (instance.usesLegacyLaunch()) {
-            cpb.append(File.pathSeparator);
+            Path legacyLaunchJarPath = FileSystem.LIBRARIES.resolve("launcher/legacy-launch.jar");
 
-            File thisFile = new File(MCLauncher.class.getProtectionDomain().getCodeSource().getLocation().getPath());
-            String pathh = null;
             try {
-                pathh = thisFile.getCanonicalPath();
-                pathh = URLDecoder.decode(pathh, "UTF-8");
-            } catch (UnsupportedEncodingException e) {
-                pathh = System.getProperty("java.class.path");
-                LogManager.logStackTrace(e);
+                if (!Files.exists(legacyLaunchJarPath) || Files.size(legacyLaunchJarPath) != 8368l) {
+                    FileSystem.copyResourcesOutJar();
+                }
             } catch (IOException e) {
-                pathh = System.getProperty("java.class.path");
-                LogManager.logStackTrace(e);
+                LogManager.logStackTrace("Failed to copy legacy-launch.jar to libraries folder", e);
             }
-            cpb.append(pathh);
+
+            cpb.append(File.pathSeparator);
+            cpb.append(legacyLaunchJarPath.toAbsolutePath().toString());
         }
 
         List<String> arguments = new ArrayList<>();
@@ -384,12 +378,12 @@ public class MCLauncher {
         }
 
         if (instance.usesLegacyLaunch()) {
-            arguments.add(LegacyMCLauncher.class.getCanonicalName());
+            arguments.add("com.atlauncher.mclauncher.legacy.LegacyMCLauncher");
             // Start or passed in arguments
             arguments.add(instance.getRootDirectory().getAbsolutePath()); // Path
             arguments.add(username); // Username
             arguments.add(account.getSessionToken()); // Session
-            arguments.add(instance.getName()); // Instance Name
+            arguments.add(Constants.LAUNCHER_NAME + " - " + instance.getName()); // Frame title
             arguments.add(App.settings.windowWidth + ""); // Window Width
             arguments.add(App.settings.windowHeight + ""); // Window Height
             if (App.settings.maximiseMinecraft) {