minecraft-kajetans-mod/src/main/java/me/km/utils/ReflectionUtils.java

package me.km.utils;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Map;
import java.util.Random;
import java.util.UUID;
import net.minecraft.block.Block;
import net.minecraft.block.material.Material;
import net.minecraft.entity.Entity;
import net.minecraft.entity.EntityLivingBase;
import net.minecraft.entity.item.EntityItem;
import net.minecraft.entity.passive.EntityVillager;
import net.minecraft.entity.player.EntityPlayerMP;
import net.minecraft.entity.player.PlayerCapabilities;
import net.minecraft.entity.projectile.EntityArrow;
import net.minecraft.server.management.PlayerList;
import net.minecraft.util.DamageSource;
import net.minecraft.util.FoodStats;
import net.minecraft.world.Explosion;
import net.minecraftforge.fml.relauncher.ReflectionHelper;

public class ReflectionUtils 
{    
    // -----------------------------------------------------------------------------------
    // helper stuff
    // -----------------------------------------------------------------------------------
    
    private static Method getMethod(Class c, String name, String obfusName, Class... pars)
    {
        try
        {
            return ReflectionHelper.findMethod(c, name, obfusName, pars);
        }
        catch(SecurityException | ReflectionHelper.UnableToFindMethodException ex)
        {
            System.out.println(name + ", "  + obfusName + " - " + ex);
        }
        return null;
    }
    
    private static Field getField(Class c, String... field)
    {
        try
        {
            return ReflectionHelper.findField(c, field);
        }
        catch(SecurityException | ReflectionHelper.UnableToFindFieldException ex)
        {
            System.out.println(String.join(", ", field) + " - " + ex);
        }
        return null;
    }
    
    private static <T> void setInt(T t, Field f, int i)
    {
        try
        {
            f.setInt(t, i);
        }
        catch(SecurityException | IllegalArgumentException | IllegalAccessException | NullPointerException ex)
        {
            System.out.println(f + " - " + ex);
        }
    }
    
    private static <T> int getInt(T t, Field f, int error)
    {
        try
        {
            return f.getInt(t);
        }
        catch(SecurityException | IllegalArgumentException | IllegalAccessException | NullPointerException ex)
        {
            System.out.println(f + " - " + ex);
            return error;
        }
    }
    
    private static <T> void setFloat(T t, Field f, float fl)
    {
        try
        {
            f.setFloat(t, fl);
        }
        catch(SecurityException | IllegalArgumentException | IllegalAccessException | NullPointerException ex)
        {
            System.out.println(f + " - " + ex);
        }
    }
    
    private static <T> float getFloat(T t, Field f, float error)
    {
        try
        {
            return f.getFloat(t);
        }
        catch(SecurityException | IllegalArgumentException | IllegalAccessException | NullPointerException ex)
        {
            System.out.println(f + " - " + ex);
            return error;
        }
    }
    
    private static <T> boolean getBoolean(T t, Field f, boolean error)
    {
        try
        {
            return f.getBoolean(t);
        }
        catch(SecurityException | IllegalArgumentException | IllegalAccessException | NullPointerException ex)
        {
            System.out.println(f + " - " + ex);
            return error;
        }
    }
    
    private static <T> T getFieldValue(Class<T> cast, Object o, Field f)
    {
        try
        {
            return (T) f.get(o);
        }
        catch(SecurityException | IllegalAccessException | IllegalArgumentException ex)
        {
            System.out.println(f + " - " + ex);
            return null;
        }
    }
    
    // -----------------------------------------------------------------------------------
    // villager stuff
    // -----------------------------------------------------------------------------------
    
    private final static Field CARRER_LEVEL = getField(EntityVillager.class, "field_175562_bw", "careerLevel");
    
    public static void setCareerLevel(EntityVillager v, int level)
    {
        setInt(v, CARRER_LEVEL, level);
    }
    
    // -----------------------------------------------------------------------------------
    // food stats
    // -----------------------------------------------------------------------------------
    
    private final static Field FOOD_EXHAUSTION_LEVEL = getField(FoodStats.class, "field_75126_c", "foodExhaustionLevel");
    
    public static void setExhaustion(FoodStats stats, float f)
    {
        setFloat(stats, FOOD_EXHAUSTION_LEVEL, f);
    }
    
    public static float getExhaustion(FoodStats stats)
    {
        return getFloat(stats, FOOD_EXHAUSTION_LEVEL, 0);
    }
    
    private final static Field FOOD_SATURATION_LEVEL = getField(FoodStats.class, "field_75125_b", "foodSaturationLevel");
    
    public static void setSaturation(FoodStats stats, float f)
    {
        setFloat(stats, FOOD_SATURATION_LEVEL, f);
    }
    
    public static float getSaturation(FoodStats stats)
    {
        return getFloat(stats, FOOD_SATURATION_LEVEL, 0);
    }
    
    // -----------------------------------------------------------------------------------
    // player stats
    // -----------------------------------------------------------------------------------
    
    private final static Field FLY_SPEED = getField(PlayerCapabilities.class, "field_75096_f", "flySpeed");
    
    public static void setFlySpeed(PlayerCapabilities cap, float f)
    {
        setFloat(cap, FLY_SPEED, f);
    }
    
    private final static Field WALK_SPEED = getField(PlayerCapabilities.class, "field_75097_g", "walkSpeed");
    
    public static void setWalkSpeed(PlayerCapabilities cap, float f)
    {
        setFloat(cap, WALK_SPEED, f);
    }
    
    // -----------------------------------------------------------------------------------
    // explosion stuff
    // -----------------------------------------------------------------------------------
    
    private final static Field IS_FLAMING = getField(Explosion.class, "field_77286_a", "causesFire");
    private final static Field IS_SMOKING = getField(Explosion.class, "field_82755_b", "damagesTerrain");
    private final static Field EXPLOSION_RNG = getField(Explosion.class, "field_77290_i", "random");
    private final static Field EXPLOSION_SIZE = getField(Explosion.class, "field_77280_f", "size");
    private final static Field EXPLODER = getField(Explosion.class, "field_77283_e", "exploder");
    
    public static boolean isFlaming(Explosion ex)
    {
        return getBoolean(ex, IS_FLAMING, false);
    }
    
    public static boolean isSmoking(Explosion ex)
    {
        return getBoolean(ex, IS_SMOKING, false);
    }
    
    public static Random getRandom(Explosion ex)
    {
        return getFieldValue(Random.class, ex, EXPLOSION_RNG);
    }
    
    public static float getSize(Explosion ex)
    {
        return getFloat(ex, EXPLOSION_SIZE, 1); // 1 for preventing zero dividing
    }
    
    public static void setSize(Explosion ex, float f)
    {
        setFloat(ex, EXPLOSION_SIZE, f);
    }
    
    public static Entity getExploder(Explosion ex)
    {
        return getFieldValue(Entity.class, ex, EXPLODER);
    }
    
    // -----------------------------------------------------------------------------------
    // random field gets
    // -----------------------------------------------------------------------------------
    
    private final static Field TIME_IN_GROUND = getField(EntityArrow.class, "field_184552_b", "timeInGround");
    
    public static int getArrowTimeInGround(EntityArrow arrow)
    {
        return getInt(arrow, TIME_IN_GROUND, 0);
    }
    
    private final static Field UUID_TO_PLAYER_MAP = getField(PlayerList.class, "field_177454_f", "uuidToPlayerMap");
    
    public static Map<UUID, EntityPlayerMP> getUuidToPlayerMap(PlayerList list)
    {
        return getFieldValue(Map.class, list, UUID_TO_PLAYER_MAP);
    }
    
    private final static Field ENTITY_ITEM_AGE = getField(EntityItem.class, "field_70292_b", "age");
    
    public static int getAge(EntityItem item)
    {
        return getInt(item, ENTITY_ITEM_AGE, 0);
    }
    
    public static void setAge(EntityItem item, int age)
    {
        setInt(item, ENTITY_ITEM_AGE, age);
    }
    
    private final static Field BLOCK_MATERIAL = getField(Block.class, "field_149764_J", "blockMaterial");
    
    public static Material getBlockMaterial(Block b)
    {
        return getFieldValue(Material.class, b, BLOCK_MATERIAL);
    }
    
    // -----------------------------------------------------------------------------------
    // EntityLivingBase stuff
    // -----------------------------------------------------------------------------------
    
    private final static Method APPLY_ARMOR_CALCULATIONS = getMethod(
            EntityLivingBase.class, 
            "applyArmorCalculations", 
            "func_70655_b", DamageSource.class, float.class);
    
    public static float applyArmorCalculations(EntityLivingBase liv, DamageSource ds, float damage)
    {
        try
        {
            return (float) APPLY_ARMOR_CALCULATIONS.invoke(liv, ds, damage);
        }
        catch(IllegalAccessException | IllegalArgumentException | InvocationTargetException ex)
        {
            return damage;
        }
    }
    
    private final static Method APPLY_POTION_DAMAGE_CALCULATIONS = getMethod(
            EntityLivingBase.class, 
            "applyPotionDamageCalculations", 
            "func_70672_c", DamageSource.class, float.class);
    
    public static float applyPotionDamageCalculations(EntityLivingBase liv, DamageSource ds, float damage)
    {
        try
        {
            return (float) APPLY_POTION_DAMAGE_CALCULATIONS.invoke(liv, ds, damage);
        }
        catch(IllegalAccessException | IllegalArgumentException | InvocationTargetException ex)
        {
            return damage;
        }
    }
    
    private final static Method DAMAGE_ARMOR = getMethod(
            EntityLivingBase.class, 
            "damageArmor", 
            "func_70675_k", float.class);
    
    public static void damageArmor(EntityLivingBase liv, float damage)
    {
        try
        {
            DAMAGE_ARMOR.invoke(liv, damage);
        }
        catch(IllegalAccessException | IllegalArgumentException | InvocationTargetException ex)
        {
        }
    }
}