minecraft-kajetans-text-core-mod/src/main/java/me/ktcm/events/Hooks.java

package me.ktcm.events;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import net.minecraft.client.Minecraft;
import net.minecraftforge.fml.relauncher.ReflectionHelper;
import net.minecraft.client.gui.FontRenderer;

public class Hooks 
{
    public static int onColorCodeChosen(char c, boolean shadow)
    {
        switch(c)
        {
            case '0': return 0;
            case '1': return 1;
            case '2': return 2;
            case '3': return 3;
            case '4': return 4;
            case '5': return 5;
            case '6': return 6;
            case '7': return 7;
            case '8': return 8;
            case '9': return 9;
            case 'a': return 10;
            case 'b': return 11;
            case 'c': return 12;
            case 'd': return 13;
            case 'e': return 14;
            case 'f': return 15;
            case 'k': return 16;
            case 'l': return 17;
            case 'm': return 18;
            case 'n': return 19;
            case 'o': return 20;
            case 'r': return 21;
            case 'A': return 10;
            case 'B': return 11;
            case 'C': return 12;
            case 'D': return 13;
            case 'E': return 14;
            case 'F': return 15;
            case 'K': return 16;
            case 'L': return 17;
            case 'M': return 18;
            case 'N': return 19;
            case 'O': return 20;
            case 'R': return 21;
            
            // brown
            case 'g': 
            case 'G': setColor(shadow, 0.4f, 0.2f, 0.0f, 0.1f, 0.05f, 0.0f); return 22;
            case 'h': 
            case 'H': setColor(shadow, 0.6f, 0.4f, 0.2f, 0.15f, 0.1f, 0.05f); return 22;
            
            // blue
            case 'i': 
            case 'I': setColor(shadow, 0.0f, 0.2f, 0.4f, 0.0f, 0.05f, 0.1f); return 22;
            case 'j': 
            case 'J': setColor(shadow, 0.0f, 0.4f, 0.6f, 0.0f, 0.1f, 0.15f); return 22;
            
            // green
            case 'p': 
            case 'P': setColor(shadow, 0.4f, 0.6f, 0.0f, 0.1f, 0.15f, 0.0f); return 22;
            case 'q': 
            case 'Q': setColor(shadow, 0.6f, 0.8f, 0.0f, 0.15f, 0.2f, 0.0f); return 22;
            
            // cyan
            case 's': 
            case 'S': setColor(shadow, 0.0f, 0.6f, 1.0f, 0.0f, 0.15f, 0.25f); return 22;
            case 't': 
            case 'T': setColor(shadow, 0.4f, 0.8f, 1.0f, 0.1f, 0.2f, 0.25f); return 22;
            
            // red
            case 'u': 
            case 'U': setColor(shadow, 0.6f, 0.2f, 0.0f, 0.15f, 0.05f, 0.0f); return 22;
            case 'v': 
            case 'V': setColor(shadow, 0.8f, 0.4f, 0.0f, 0.2f, 0.1f, 0.0f); return 22;
            
            
            // violet
            case 'w': 
            case 'W': setColor(shadow, 0.4f, 0.0f, 0.4f, 0.1f, 0.0f, 0.1f); return 22;
            case 'x': 
            case 'X': setColor(shadow, 0.6f, 0.0f, 0.8f, 0.15f, 0.0f, 0.2f); return 22;
            
            // yellow
            case 'y': 
            case 'Y': setColor(shadow, 0.8f, 0.6f, 0.0f, 0.2f, 0.15f, 0.0f); return 22;
            case 'z': 
            case 'Z': setColor(shadow, 1.0f, 0.8f, 0.0f, 0.25f, 0.2f, 0.0f); return 22;
        }
        return -1;
    }
    
    private static void setColor(boolean shadow, float r, float g, float b, float dr, float dg, float db)
    {
        if(shadow)
        {
            setColor(dr, dg, db);
        }
        else
        {
            setColor(r, g, b);
        }
    }
    
    private static Method getMethod(Class c, String name, String oName, Class... classes)
    {
        try
        {
            return ReflectionHelper.findMethod(c, name, oName, classes);
        }
        catch(SecurityException | ReflectionHelper.UnableToFindFieldException ex)
        {
            System.out.println(name + " - " + oName + " - " + 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 final static FontRenderer FONT = Minecraft.getMinecraft().fontRenderer;
    // /home/kajetan/.gradle/caches/minecraft/de/oceanlabs/mcp/mcp_snapshot/20171003/1.12.2/srgs/mcp-srg.srg
    // FD: net/minecraft/client/gui/FontRenderer/alpha net/minecraft/client/gui/FontRenderer/field_78305_q
    private final static Field ALPHA = getField(FontRenderer.class, "field_78305_q", "alpha");
    
    public static float getAlpha()
    {
        try
        {
            return ALPHA.getFloat(FONT);
        }
        catch(SecurityException | IllegalAccessException | IllegalArgumentException ex)
        {
            return 1;
        }
    }
    
    private final static Method SET_COLOR = getMethod(FontRenderer.class, "setColor", null, float.class, float.class, float.class, float.class);
    
    public static void setColor(float r, float g, float b)
    {
        try
        {
            SET_COLOR.invoke(FONT, r, g, b, getAlpha());
        }
        catch(IllegalAccessException | IllegalArgumentException | InvocationTargetException ex)
        {
            ex.printStackTrace();
        }
    }
}