package shapes;

import java.util.ArrayList;

import javax.media.opengl.GL;

import processing.core.PApplet;
import mekstension.Mekstension;

public class ShapeRenderer
{
    Mekstension p;
    
    public nvArray GLblendL = new nvArray();
    public nvArray GLblendR = new nvArray();
    private boolean blnDisableZTest = true;
    public boolean enableBlend = false;
    
    /**
     * Constructor
     * @param p_ {@link Mekstension} parent, extended from {@link PApplet}
     * @see PApplet
     */
    public ShapeRenderer(Mekstension p_)
    {
        p = p_;
        
        GLblendL.add("GL_ONE",GL.GL_ONE);
        GLblendL.add("GL_SRC_COLOR",GL.GL_SRC_COLOR); 
        GLblendL.add("GL_ONE_MINUS_SRC_COLOR",GL.GL_ONE_MINUS_SRC_COLOR); 
        GLblendL.add("GL_DST_COLOR",GL.GL_DST_COLOR); 
        GLblendL.add("GL_ONE_MINUS_DST_COLOR",GL.GL_ONE_MINUS_DST_COLOR);     
        GLblendL.add("GL_SRC_ALPHA",GL.GL_SRC_ALPHA); 
        GLblendL.add("GL_ONE_MINUS_SRC_ALPHA",GL.GL_ONE_MINUS_SRC_ALPHA);     
        GLblendL.add("GL_DST_ALPHA",GL.GL_DST_ALPHA); 
        GLblendL.add("GL_ONE_MINUS_DST_ALPHA",GL.GL_ONE_MINUS_DST_ALPHA);     
        GLblendL.add("GL_SRC_ALPHA_SATURATE",GL.GL_SRC_ALPHA_SATURATE);   
        GLblendL.add("GL_CONSTANT_COLOR",GL.GL_CONSTANT_COLOR ); 
        GLblendL.add("GL_ONE_MINUS_CONSTANT_COLOR",GL.GL_ONE_MINUS_CONSTANT_COLOR); 
        GLblendL.add("GL_CONSTANT_ALPHA",GL.GL_CONSTANT_ALPHA ); 
        GLblendL.add("GL_ONE_MINUS_CONSTANT_ALPHA",GL.GL_ONE_MINUS_CONSTANT_ALPHA);
        GLblendL.add("GL_ZERO",GL.GL_ZERO);
           
        GLblendR.add("GL_ONE",GL.GL_ONE);     
        GLblendR.add("GL_SRC_COLOR",GL.GL_SRC_COLOR); 
        GLblendR.add("GL_ONE_MINUS_SRC_COLOR",GL.GL_ONE_MINUS_SRC_COLOR); 
        GLblendR.add("GL_DST_COLOR",GL.GL_DST_COLOR); 
        GLblendR.add("GL_ONE_MINUS_DST_COLOR",GL.GL_ONE_MINUS_DST_COLOR);     
        GLblendR.add("GL_SRC_ALPHA",GL.GL_SRC_ALPHA); 
        GLblendR.add("GL_ONE_MINUS_SRC_ALPHA",GL.GL_ONE_MINUS_SRC_ALPHA);     
        GLblendR.add("GL_DST_ALPHA",GL.GL_DST_ALPHA); 
        GLblendR.add("GL_ONE_MINUS_DST_ALPHA",GL.GL_ONE_MINUS_DST_ALPHA);
        GLblendR.add("GL_CONSTANT_COLOR",GL.GL_CONSTANT_COLOR ); 
        GLblendR.add("GL_ONE_MINUS_CONSTANT_COLOR",GL.GL_ONE_MINUS_CONSTANT_COLOR); 
        GLblendR.add("GL_CONSTANT_ALPHA",GL.GL_CONSTANT_ALPHA ); 
        GLblendR.add("GL_ONE_MINUS_CONSTANT_ALPHA",GL.GL_ONE_MINUS_CONSTANT_ALPHA);
        GLblendR.add("GL_ZERO",GL.GL_ZERO);
    }
    
    
    /**
     * draw loop
     */
    public void draw(ShapeList shapelist)
    {
        if ( enableBlend ) {
            if( blnDisableZTest )
                p.gl.glDisable(GL.GL_DEPTH_TEST);
            p.gl.glEnable(GL.GL_BLEND);
            p.gl.glBlendFunc( GLblendL.getCurrent(), GLblendR.getCurrent() );
        }
        
        for(int i = 0; i < shapelist.size(); i++) {
            shapelist.get(i).update();
            shapelist.get(i).draw();  
        }
        
        if( enableBlend ) {
            p.gl.glBlendFunc( GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA );   
        }        
    }
    
    
    public void nextBlendModeR()
    {
        GLblendR.next();
    }
    
    
    public void nextBlendModeL()
    {
        GLblendL.next();
    }
    
    
    public void toggleDepthTest()
    {
        blnDisableZTest = blnDisableZTest ? false : true;         
    }
    
    
    public void toggleBlend()
    {
        enableBlend = enableBlend ? false : true;
    }
    
    
    
    
    /**
     * name/value pair array
     * @author Ira Greenberg
     */
    public class nvArray 
    {
        ArrayList<String> name = new ArrayList <String> ();
        ArrayList<Integer> val = new ArrayList <Integer> ();
        
        int length;
        int pos;

        
        nvArray()
        {
          length = 0;
          pos = 0;
        }

        
        void add(String l_name, int l_val)
        {
          length++;
          name.add( l_name );
          val.add( new Integer(l_val) ); 
        }

        
        void next()
        {
          pos = (pos+1 == length)? 0 : pos+1;
        }

        
        void prev()
        {
          pos = (pos-1 <0)? length-1 : pos-1;
        }

        
        public int getCurrent()
        {
          return ( (Integer) val.get( pos ) ).intValue();
        }

        
        public String getCurrentName()
        {
          return( (String) name.get( pos ) );
        }
    }
}