package ftbsc.bscv.patches;

import ftbsc.lll.processor.annotations.Injector;
import ftbsc.lll.processor.annotations.Patch;
import ftbsc.lll.processor.annotations.Target;
import ftbsc.lll.tools.InsnSequence;
import ftbsc.lll.tools.PatternMatcher;
import net.minecraft.client.entity.player.ClientPlayerEntity;
import net.minecraftforge.common.MinecraftForge;
import net.minecraftforge.eventbus.api.Cancelable;
import net.minecraftforge.eventbus.api.Event;

import org.objectweb.asm.Opcodes;
import org.objectweb.asm.tree.*;

public class NoSlowPatch {

	@Cancelable
	public static class PlayerSlowDownEvent extends Event {	}

	public static boolean shouldSlowPlayer() {
		return MinecraftForge.EVENT_BUS.post(new PlayerSlowDownEvent());
	}

	@Patch(value = ClientPlayerEntity.class, reason = "add hook to cancel slowing down effect of using items")
	public abstract static class SlowDownOverride implements Opcodes {
		@Target
		abstract void aiStep();

		@Injector
		public void inject(ClassNode clazz, MethodNode main) {
			AbstractInsnNode found = PatternMatcher.builder()
				.opcodes(ALOAD, INVOKEVIRTUAL, IFEQ, ALOAD, INVOKEVIRTUAL, IFNE)
				.ignoreFrames()
				.ignoreLabels()
				.ignoreLineNumbers()
				.build()
				.find(main)
				.getLast();

			AbstractInsnNode after = PatternMatcher.builder()
				.opcodes(ALOAD, ICONST_0, PUTFIELD)
				.ignoreFrames()
				.ignoreLabels()
				.ignoreLineNumbers()
				.build()
				.find(main)
				.getLast();

			LabelNode skip = new LabelNode(); // TODO can we get the label that the original IF is jumping to without adding one ourselves?
			InsnSequence is = new InsnSequence();
			is.add(new MethodInsnNode(
				INVOKESTATIC,
				"ftbsc/bscv/patches/NoSlowPatch",
				"shouldSlowPlayer",
				"()Z"
			));
			is.add(new JumpInsnNode(IFNE, skip));

			main.instructions.insert(found, is);
			main.instructions.insert(after, skip);
		}
	}
}