Add mob drop viewer to item list

1 files changed, 78 insertions, 0 deletions

diff --git a/src/main/java/moe/nea/firmament/init/EarlyRiser.java b/src/main/java/moe/nea/firmament/init/EarlyRiser.java
new file mode 100644
index 0000000..268e3f3
--- /dev/null
+++ b/src/main/java/moe/nea/firmament/init/EarlyRiser.java
@@ -0,0 +1,78 @@
+/*
+ * SPDX-FileCopyrightText: 2024 Linnea Gräf <nea@nea.moe>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+package moe.nea.firmament.init;
+
+import me.shedaniel.mm.api.ClassTinkerers;
+import net.fabricmc.loader.api.FabricLoader;
+import net.fabricmc.loader.api.MappingResolver;
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.Type;
+import org.objectweb.asm.tree.*;
+
+import java.lang.reflect.Modifier;
+import java.util.Objects;
+
+public class EarlyRiser implements Runnable {
+    MappingResolver remapper = FabricLoader.getInstance().getMappingResolver();
+    String PlayerEntity = remapper.mapClassName("intermediary", "net.minecraft.class_1657");
+    String World = remapper.mapClassName("intermediary", "net.minecraft.class_1937");
+    String GameProfile = "com.mojang.authlib.GameProfile";
+    String BlockPos = remapper.mapClassName("intermediary", "net.minecraft.class_2338");
+    String AbstractClientPlayerEntity = remapper.mapClassName("intermediary", "net.minecraft.class_742");
+    String GuiPlayer = "moe.nea.firmament.gui.entity.GuiPlayer";
+    // World world, BlockPos pos, float yaw, GameProfile gameProfile
+    Type constructorDescriptor = Type.getMethodType(Type.VOID_TYPE, getTypeForClassName(World), getTypeForClassName(BlockPos), Type.FLOAT_TYPE, getTypeForClassName(GameProfile));
+
+    @Override
+    public void run() {
+        ClassTinkerers.addTransformation(AbstractClientPlayerEntity, it -> mapClassNode(it, getTypeForClassName(PlayerEntity)));
+        ClassTinkerers.addTransformation(GuiPlayer, it -> mapClassNode(it, getTypeForClassName(AbstractClientPlayerEntity)));
+    }
+
+    private void mapClassNode(ClassNode classNode, Type superClass) {
+        for (MethodNode method : classNode.methods) {
+            if (Objects.equals(method.name, "<init>") && Type.getMethodType(method.desc).equals(constructorDescriptor)) {
+                modifyConstructor(method, superClass);
+                return;
+            }
+        }
+        var node = new MethodNode(Opcodes.ASM9, "<init>", constructorDescriptor.getDescriptor(), null, null);
+        classNode.methods.add(node);
+        modifyConstructor(node, superClass);
+    }
+
+    private Type getTypeForClassName(String className) {
+        return Type.getObjectType(className.replace('.', '/'));
+    }
+
+    private void modifyConstructor(MethodNode method, Type superClass) {
+        method.access = (method.access | Modifier.PUBLIC) & ~Modifier.PRIVATE & ~Modifier.PROTECTED;
+        if (method.instructions.size() != 0) return; // Some other mod has already made a constructor here
+
+        // World world, BlockPos pos, float yaw, GameProfile gameProfile
+        // ALOAD this
+        method.instructions.add(new VarInsnNode(Opcodes.ALOAD, 0));
+
+        // ALOAD World
+        method.instructions.add(new VarInsnNode(Opcodes.ALOAD, 1));
+
+        // ALOAD BlockPos
+        method.instructions.add(new VarInsnNode(Opcodes.ALOAD, 2));
+
+        // ALOAD yaw
+        method.instructions.add(new VarInsnNode(Opcodes.FLOAD, 3));
+
+        // ALOAD gameProfile
+        method.instructions.add(new VarInsnNode(Opcodes.ALOAD, 4));
+
+        // Call super
+        method.instructions.add(new MethodInsnNode(Opcodes.INVOKESPECIAL, superClass.getInternalName(), "<init>", constructorDescriptor.getDescriptor(), false));
+
+        // Return
+        method.instructions.add(new InsnNode(Opcodes.RETURN));
+    }
+}