feat: offline user name config

headlessmc-api/src/main/java/me/earth/headlessmc/api/config/Config.java

@@ -18,4 +18,9 @@ default <T> T get(Property<T> property, T defaultValue) {
         return getValue(property, () -> defaultValue);
     }
 
+    // Implement a setter function for config properties, this allows for overwriting
+    // the values of them from the cli which enables per invocation configuration.
+    <T> T setValue(Property<T> property, Supplier<T> value);
+
+    default <T> T set(Property<T> property, T value) { return setValue(property, () -> value); }
 }

headlessmc-commons/src/main/java/me/earth/headlessmc/config/ConfigImpl.java

@@ -34,4 +34,9 @@ public <T> T getValue(Property<T> property, Supplier<T> defaultValue) {
         return result == null ? defaultValue.get() : result;
     }
 
+    @Override
+    public <T> T setValue(Property<T> property, Supplier<T> value) {
+        return (T)properties.setProperty(property.getName(), value.get().toString());
+    }
+
 }

headlessmc-launcher/src/main/java/me/earth/headlessmc/launcher/LauncherProperties.java

@@ -50,6 +50,8 @@ public interface LauncherProperties extends HmcProperties {
 
     Property<String> FABRIC_URL = string("hmc.fabric.url");
     Property<Boolean> OFFLINE = bool("hmc.offline");
+    Property<String> OFFLINE_USERNAME = string("hmc.offline.username");
+    Property<String> OFFLINE_UUID = string("hmc.offline.uuid");
     Property<Boolean> RE_THROW_LAUNCH_EXCEPTIONS = bool("hmc.rethrow.launch.exceptions");
 
     // TODO: also check hashes for the libraries?

headlessmc-launcher/src/main/java/me/earth/headlessmc/launcher/auth/AccountManager.java

@@ -44,7 +44,9 @@ public Account login(Config config) throws AuthException {
         }
 
         if (offlineChecker.isOffline()) {
-            return new Account("Offline", OFFLINE_UUID, "", "", "", "");
+            val username = config.get(LauncherProperties.OFFLINE_USERNAME, "Offline");
+            val uuid = config.get(LauncherProperties.OFFLINE_UUID, OFFLINE_UUID);
+            return new Account(username, uuid, "", "", "", "");
         }
 
         log.warning("No valid account found!");

headlessmc-launcher/src/main/java/me/earth/headlessmc/launcher/command/LaunchCommand.java

@@ -39,6 +39,7 @@ public LaunchCommand(Launcher launcher) {
         // TODO: is this really necessary?
         args.put("-noout", "Doesn't print Minecrafts output to the console.");
         args.put("-quit", "Quit HeadlessMc after launching the game.");
+        args.put("-username", "Set the username in offline mode");
         args.put("--jvm", "Jvm args to use.");
     }
 

headlessmc-launcher/src/main/java/me/earth/headlessmc/launcher/files/SystemPropertiesConfig.java

@@ -16,4 +16,8 @@ public <T> T getValue(Property<T> property, Supplier<T> defaultValue) {
         return result == null ? defaultValue.get() : result;
     }
 
+    @Override
+    public <T> T setValue(Property<T> property, Supplier<T> value) {
+        return property.parse(System.setProperty(property.getName(), value.get().toString()));
+    }
 }

headlessmc-launcher/src/main/java/me/earth/headlessmc/launcher/launch/LaunchOptions.java

@@ -33,14 +33,15 @@ public class LaunchOptions {
     private final boolean noOut;
     private final boolean noIn;
     private final boolean inMemory;
+    private final String username;
 
     public static class LaunchOptionsBuilder {
         private LaunchOptionsBuilder() {
             this.additionalJvmArgs = Collections.emptyList();
         }
 
         public LaunchOptionsBuilder parseFlags(
-            Launcher ctx, boolean quit, String... args) {
+                Launcher ctx, boolean quit, String... args) {
             boolean lwjgl = flag(ctx, "-lwjgl", INVERT_LWJGL_FLAG, args);
             // if offline only allow launching with the lwjgl flag!
             if (!lwjgl && launcher.getAccountManager().getOfflineChecker().isOffline()) {
@@ -57,23 +58,24 @@ public LaunchOptionsBuilder parseFlags(
                 .paulscode(flag(ctx, "-paulscode", INVERT_PAULS_FLAG, args))
                 .noOut(quit || CommandUtil.hasFlag("-noout", args))
                 .parseJvmArgs(args)
-                .noIn(quit);
+                .noIn(quit)
+                .username(CommandUtil.getOption("-username", args));
         }
 
         public LaunchOptionsBuilder parseJvmArgs(String... args) {
             String jvmArgs = CommandUtil.getOption("--jvm", args);
             if (jvmArgs != null) {
                 this.additionalJvmArgs = new ArrayList<>(
-                    Arrays.asList(CommandUtil.split(jvmArgs)));
+                        Arrays.asList(CommandUtil.split(jvmArgs)));
             }
 
             return this;
         }
 
         private boolean flag(
-            HasConfig ctx, String flg, Property<Boolean> inv, String... args) {
+                HasConfig ctx, String flg, Property<Boolean> inv, String... args) {
             return CommandUtil.hasFlag(flg, args)
-                ^ ctx.getConfig().get(inv, false);
+                    ^ ctx.getConfig().get(inv, false);
         }
     }
 

headlessmc-launcher/src/main/java/me/earth/headlessmc/launcher/launch/ProcessFactory.java

@@ -19,10 +19,7 @@
 
 import java.io.File;
 import java.io.IOException;
-import java.util.ArrayList;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Set;
+import java.util.*;
 import java.util.zip.ZipFile;
 
 @CustomLog
@@ -40,7 +37,14 @@ public Process run(LaunchOptions options)
 
     public Process run(LaunchOptions options, Instrumentation instrumentation)
         throws IOException, LaunchException, AuthException {
+
         val launcher = options.getLauncher();
+
+        if (options.getUsername() != null) {
+            launcher.getConfig().set(LauncherProperties.OFFLINE_USERNAME, options.getUsername());
+            launcher.getConfig().set(LauncherProperties.OFFLINE_UUID, UUID.randomUUID().toString());
+        }
+
         if (launcher.getAccountManager().getLastAccount() == null) {
             launcher.getAccountManager().login(launcher.getConfig());
         }