#include <azur/gint/render.h>
#include "mandelbrotshader.h"
#include <cstdlib>
#include <cstdio>

#include <gint/rtc.h>
#include <gint/usb.h>
#include <gint/usb-ff-bulk.h>

#include <num/num.h>



uint8_t AZRP_SHADER_MANDELBROT = -1;


__attribute__((constructor))
static void register_shader(void)
{
    extern azrp_shader_t azrp_shader_mandelbrot;
    AZRP_SHADER_MANDELBROT = azrp_register_shader(azrp_shader_mandelbrot);
}


void azrp_shader_mandelbrot_configure(void)
{
    azrp_set_uniforms(AZRP_SHADER_MANDELBROT, (void *)azrp_width);
}


void azrp_mandelbrot_USBDEBUG( void )
{
    char texttosend[1024];

    sprintf( texttosend, "data" );
    usb_fxlink_text(texttosend, 0);

}


void azrp_mandelbrot_init( )
{

}


void azrp_mandelbrot_close( void )
{

}


struct command {
    uint8_t shader_id;
    uint8_t current_frag;
    libnum::num xmin;
    libnum::num xmax;
    libnum::num ymin;
    libnum::num ymax;
    libnum::num xinc;
    libnum::num yinc;
};


void azrp_mandelbrot( void )
{
    prof_enter(azrp_perf_cmdgen);

    struct command cmd;

    cmd.shader_id = AZRP_SHADER_MANDELBROT;
    cmd.current_frag = 0;
    cmd.xmin = libnum::num(-1.98f);
    cmd.xmax = libnum::num(1.98f);
    cmd.ymin = libnum::num(-1.12f);
    cmd.ymax = libnum::num(1.12f);
    cmd.xinc = libnum::num((2*1.98f)/azrp_width);
    cmd.yinc = libnum::num((2*1.12f)/azrp_height);
    int fragmin = 0;
    int fragcount = (azrp_height >> 4) + 1;

    azrp_queue_command(&cmd, sizeof cmd, fragmin, fragcount);
    prof_leave(azrp_perf_cmdgen);
}


void azrp_shader_mandelbrot( void *uniforms, void *comnd, void *fragment )
{
    struct command *cmd = (struct command *) comnd;
    uint16_t *frag = (uint16_t *) fragment;

    int maxiter = 256;
    libnum::num cr = libnum::num(-0.480f);
    libnum::num ci = libnum::num(0.600f);


    for( int j=0; j<16; j++)
    {
        int offset = azrp_width * j;

        for( int i=0; i<azrp_width; i++ )
        {
           
            libnum::num zr = cmd->xmin + libnum::num(i)* cmd->xinc;       
            libnum::num zi = cmd->ymax - libnum::num(cmd->current_frag*16)*cmd->yinc - libnum::num(j)*cmd->yinc;

            libnum::num zr2 = zr * zr;
            libnum::num zi2 = zi * zi;

            int u=0;

            while((zr2+zi2)<4 && (u<maxiter))
            {
                libnum::num temp = zr;
                zr2 = zr * zr;
                zi2 = zi * zi;
                zr = zr2 - zi2 + cr;
                zi = 2*zi*temp + ci;
                u++;
            }

            if(u==maxiter)
            {
                frag[offset + i] = 0x0000;
            }
            else
            {
                int CR, CG, CB;

                if (u<maxiter/4)
                {
                    CR = 0;
                    CG = u*4;
                    CB = 255;
                }
                else if (u<2*maxiter/4)
                {
                    CR = 0;
                    CG = 255;
                    CB = 255-(u-maxiter)/4;
                }
                else if (u<3*maxiter/4)
                {
                    CR = (u-2*maxiter)/4;
                    CG = 255;
                    CB = 0;
                }
                else if (u<4*maxiter/4)
                {
                    CR = 255;
                    CG = 255-(u-3*maxiter)/4;
                    CB = 0;
                }

                frag[offset + i] = C_RGB(CR,CG,CB);
            }


        }
      
    }

    cmd->current_frag++;
}