Support Legacy Fabric

Author: 3arthqu4ke

headlessmc-launcher/build.gradle

@@ -28,6 +28,7 @@ dependencies {
     jarLibs group: 'org.ow2.asm', name: 'asm-tree', version: '9.7'
     jarLibs group: 'com.google.code.gson', name: 'gson', version: '2.10.1'
     jarLibs group: 'dev.xdark', name: 'deencapsulation', version: '1.0'
+    jarLibs 'org.semver4j:semver4j:5.3.0'
     jarLibs project(':headlessmc-jline')
 
     includeJarInResources ('net.kunmc.lab:forgecli:1.2.0:all') {

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

@@ -2,7 +2,6 @@
 
 import lombok.CustomLog;
 import lombok.Getter;
-import lombok.val;
 import me.earth.headlessmc.api.command.CommandException;
 import me.earth.headlessmc.api.command.CommandUtil;
 import me.earth.headlessmc.api.command.ParseUtil;
@@ -13,6 +12,8 @@
 import me.earth.headlessmc.launcher.launch.SimpleInMemoryLauncher;
 import me.earth.headlessmc.launcher.launch.SystemPropertyHelper;
 import me.earth.headlessmc.launcher.version.Version;
+import me.earth.headlessmc.launcher.version.VersionUtil;
+import me.earth.headlessmc.launcher.version.family.FamilyUtil;
 
 import java.io.File;
 import java.io.IOException;
@@ -22,8 +23,8 @@
 @Getter
 @CustomLog
 public class FabricCommand extends AbstractVersionCommand {
-    private static final String URL = "https://maven.fabricmc.net/" +
-            "net/fabricmc/fabric-installer/0.11.0/fabric-installer-0.11.0.jar";
+    private static final String LEGACY = "https://maven.legacyfabric.net/net/legacyfabric/fabric-installer/1.0.0/fabric-installer-1.0.0.jar";
+    private static final String URL = "https://maven.fabricmc.net/net/fabricmc/fabric-installer/0.11.0/fabric-installer-0.11.0.jar";
 
     private final SimpleInMemoryLauncher inMemoryLauncher = new SimpleInMemoryLauncher();
 
@@ -41,8 +42,14 @@ public void execute(Version ver, String... args) throws CommandException {
         ctx.log("Installing Fabric for version " + ver.getName() + "...");
         FileManager tempFiles = ctx.getFileManager().createRelative(UUID.randomUUID().toString());
         File jar = tempFiles.create("fabric-installer.jar");
-        String url = ctx.getConfig().get(LauncherProperties.FABRIC_URL, URL);
+        Version vanilla = FamilyUtil.getOldestParent(ver);
+        String defaultUrl = URL;
+        if (VersionUtil.isOlderThanSafe(vanilla.getName(), "1.14") && !CommandUtil.hasFlag("-forcenew", args) || CommandUtil.hasFlag("-legacy", args)) {
+            ctx.log("Using Legacy Fabric...");
+            defaultUrl = LEGACY;
+        }
 
+        String url = ctx.getConfig().get(LauncherProperties.FABRIC_URL, defaultUrl);
         try {
             downloadInstaller(url, jar);
             install(ver, jar, args);

headlessmc-launcher/src/main/java/me/earth/headlessmc/launcher/version/VersionUtil.java

@@ -1,12 +1,15 @@
 package me.earth.headlessmc.launcher.version;
 
+import lombok.CustomLog;
 import lombok.experimental.UtilityClass;
 import me.earth.headlessmc.api.HasName;
 import me.earth.headlessmc.api.util.Table;
+import org.semver4j.Semver;
 
 import java.util.Collection;
 import java.util.stream.Collectors;
 
+@CustomLog
 @UtilityClass
 public final class VersionUtil {
     public static Collection<Version> releases(Collection<Version> versions) {
@@ -19,10 +22,30 @@ public static String makeTable(Collection<Version> versions) {
         return new Table<Version>()
             .withColumn("id", v -> String.valueOf(v.getId()))
             .withColumn("name", HasName::getName)
-            .withColumn("parent", v -> v.getParent() == null
-                ? "" : v.getParent().getName())
+            .withColumn("parent", v -> v.getParent() == null ? "" : v.getParent().getName())
             .addAll(versions)
             .build();
     }
 
+    public static boolean isOlderThanSafe(String versionToTest, String versionPotentiallyYounger) {
+        try {
+            return isOlderThan(versionToTest, versionPotentiallyYounger);
+        } catch (IllegalArgumentException e) {
+            log.error(e);
+            return false;
+        }
+    }
+
+    public static boolean isOlderThan(String versionToTest, String versionPotentiallyYounger) throws IllegalArgumentException {
+        try {
+            Semver semver1 = Semver.coerce(versionToTest);
+            Semver semver2 = Semver.coerce(versionPotentiallyYounger);
+            assert semver1 != null;
+            assert semver2 != null;
+            return semver1.compareTo(semver2) < 0;
+        } catch (Exception e) {
+            throw new IllegalArgumentException("Unable to parse semver '" + versionToTest + "' or '" + versionPotentiallyYounger + "'", e);
+        }
+    }
+
 }

headlessmc-launcher/src/test/java/me/earth/headlessmc/launcher/version/VersionUtilTest.java

@@ -0,0 +1,25 @@
+package me.earth.headlessmc.launcher.version;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class VersionUtilTest {
+    @Test
+    public void testIsOlderThan() {
+        assertTrue(VersionUtil.isOlderThan("1.12.2", "1.21.1"));
+        assertTrue(VersionUtil.isOlderThan("1.11", "2.0.0"));
+        assertTrue(VersionUtil.isOlderThanSafe("1.12.1", "1.12.2"));
+        assertFalse(VersionUtil.isOlderThan("1.2.1", "1.1.1"));
+        assertFalse(VersionUtil.isOlderThan("2.0.0", "1.1.1"));
+        assertFalse(VersionUtil.isOlderThanSafe("1.1.2", "1.1.1"));
+
+        assertFalse(VersionUtil.isOlderThanSafe("1.15", "1.15.0"));
+        assertFalse(VersionUtil.isOlderThanSafe("1.15.0", "1.15"));
+
+        assertFalse(VersionUtil.isOlderThanSafe("1.15", "1.14.4"));
+        assertTrue(VersionUtil.isOlderThanSafe("1.14.4", "1.15"));
+    }
+
+}