SlightlyVanilla/src/main/java/com/thebrokenrail/slightlyvanilla/mixin/MixinPlayerEntity.java

package com.thebrokenrail.slightlyvanilla.mixin;

import com.thebrokenrail.slightlyvanilla.SlightlyVanilla;
import net.minecraft.entity.damage.DamageSource;
import net.minecraft.entity.player.PlayerAbilities;
import net.minecraft.entity.player.PlayerEntity;
import org.objectweb.asm.Opcodes;
import org.spongepowered.asm.mixin.Mixin;
import org.spongepowered.asm.mixin.injection.At;
import org.spongepowered.asm.mixin.injection.ModifyArg;
import org.spongepowered.asm.mixin.injection.Redirect;

@SuppressWarnings("unused")
@Mixin(PlayerEntity.class)
public class MixinPlayerEntity {
    @ModifyArg(at = @At(value = "INVOKE", target = "Lnet/minecraft/entity/Entity;damage(Lnet/minecraft/entity/damage/DamageSource;F)Z"), method = "attack", index = 1)
    public float changeDamage(DamageSource source, float amount) {
        //noinspection ConstantConditions
        if (SlightlyVanilla.getConfig().instantKillInCreative && ((PlayerEntity) (Object) this).isCreative()) {
            return Float.MAX_VALUE;
        } else {
            return amount;
        }
    }

    @Redirect(at = @At(value = "FIELD", opcode = Opcodes.GETFIELD, target = "Lnet/minecraft/entity/player/PlayerAbilities;invulnerable:Z"), method = "getMaxNetherPortalTime")
    public boolean adjustMaxNetherPortalTime(PlayerAbilities playerAbilities) {
        if (SlightlyVanilla.getConfig().disableInstantNetherPortalInCreative) {
            return false;
        } else {
            return playerAbilities.invulnerable;
        }
    }
}