mod version

src/main/java/com/kasetoatz/fastGhast/FastGhast.java

@@ -1,57 +1,14 @@
-package com.kasetoatz.fastGhast;
+package com.kasetoatz.fastghast;
 
-import org.bukkit.Bukkit;
-import org.bukkit.attribute.Attribute;
-import org.bukkit.attribute.AttributeInstance;
-import org.bukkit.entity.*;
-import org.bukkit.event.EventHandler;
-import org.bukkit.event.Listener;
-import org.bukkit.event.entity.EntityDismountEvent;
-import org.bukkit.event.entity.EntityMountEvent;
-import org.bukkit.plugin.java.JavaPlugin;
-import io.papermc.paper.entity.Leashable;
+import net.fabricmc.api.ModInitializer;
 
-public final class FastGhast extends JavaPlugin implements Listener
+import static com.kasetoatz.fastghast.config.Config.load;
+
+public class Fastghast implements ModInitializer
 {
-    private static final double DEFAULT = 0.05;
-    private double SPEED;
-
     @Override
-    public void onEnable()
+    public void onInitialize()
     {
-        saveDefaultConfig();
-        SPEED = getConfig().getDouble("speed");
-        getServer().getPluginManager().registerEvents(this, this);
-        Bukkit.getScheduler().runTaskTimer(this, () -> {
-            getServer().getWorlds().forEach(world -> world.getEntities().forEach(entity -> {
-                if (entity instanceof Leashable leashed && leashed.isLeashed() && leashed.getLeashHolder() instanceof HappyGhast ghast && leashed.getLocation().distance(ghast.getLocation()) > 8) {
-                    leashed.teleport(ghast.getLocation());
-                }
-            }));
-        }, 0, 1);
-    }
-
-    private void setSpeed(Entity entity, double speed)
-    {
-        if (entity instanceof HappyGhast ghast)
-        {
-            AttributeInstance attr = ghast.getAttribute(Attribute.FLYING_SPEED);
-            if (attr != null)
-            {
-                attr.setBaseValue(speed);
-            }
-        }
-    }
-
-    @EventHandler
-    public void onEntityMount(EntityMountEvent event)
-    {
-        setSpeed(event.getMount(), SPEED);
-    }
-
-    @EventHandler
-    public void onEntityDismount(EntityDismountEvent event)
-    {
-        setSpeed(event.getDismounted(), DEFAULT);
+        load();
     }
 }

src/main/java/com/kasetoatz/fastGhast/config/Config.java

@@ -0,0 +1,62 @@
+package com.kasetoatz.fastghast.config;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonObject;
+import net.fabricmc.loader.api.FabricLoader;
+import net.minecraft.util.crash.CrashException;
+import net.minecraft.util.crash.CrashReport;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+public class Config
+{
+    public static double UNMOUNTED_SPEED = 0.05;
+    public static double MOUNTED_SPEED = 0.15;
+
+    private static final Path FILE = FabricLoader.getInstance().getConfigDir().resolve("fastghast.json");
+    private static final Gson GSON = new GsonBuilder().setPrettyPrinting().create();
+
+    public static void load() {
+        if (!Files.exists(FILE))
+        {
+            save();
+            return;
+        }
+        try
+        {
+            String json = Files.readString(FILE);
+            JsonObject data = GSON.fromJson(json, JsonObject.class);
+            if (data.has("unmounted-speed"))
+            {
+                UNMOUNTED_SPEED = data.get("unmounted-speed").getAsDouble();
+            }
+            if (data.has("mounted-speed"))
+            {
+                MOUNTED_SPEED = data.get("mounted-speed").getAsDouble();
+            }
+            save();
+        }
+        catch (IOException exc)
+        {
+            throw new CrashException(CrashReport.create(exc, "Loading config file."));
+        }
+    }
+
+    private static void save()
+    {
+        try
+        {
+            JsonObject data = new JsonObject();
+            data.addProperty("unmounted-speed", UNMOUNTED_SPEED);
+            data.addProperty("mounted-speed", MOUNTED_SPEED);
+            Files.writeString(FILE, GSON.toJson(data));
+        }
+        catch (IOException exc)
+        {
+            throw new CrashException(CrashReport.create(exc, "Saving config file."));
+        }
+    }
+}

src/main/java/com/kasetoatz/fastGhast/mixin/HappyGhastMixin.java

@@ -0,0 +1,27 @@
+package com.kasetoatz.fastghast.mixin;
+
+import net.minecraft.entity.LivingEntity;
+import net.minecraft.entity.attribute.EntityAttribute;
+import net.minecraft.entity.passive.HappyGhastEntity;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.registry.entry.RegistryEntry;
+import org.jetbrains.annotations.Nullable;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Redirect;
+
+import static com.kasetoatz.fastghast.config.Config.MOUNTED_SPEED;
+import static com.kasetoatz.fastghast.config.Config.UNMOUNTED_SPEED;
+
+@Mixin(HappyGhastEntity.class)
+public abstract class HappyGhastMixin
+{
+    @Shadow @Nullable public abstract LivingEntity getControllingPassenger();
+
+    @Redirect(method="travel", at=@At(value="INVOKE", target="Lnet/minecraft/entity/passive/HappyGhastEntity;getAttributeValue(Lnet/minecraft/registry/entry/RegistryEntry;)D"))
+    public double speed(HappyGhastEntity instance, RegistryEntry<EntityAttribute> registryEntry)
+    {
+        return getControllingPassenger() instanceof PlayerEntity ? MOUNTED_SPEED : UNMOUNTED_SPEED;
+    }
+}