/* (C) Guenter Geiger <geiger@epy.co.at> */


#include "math.h"
#include <m_pd.h>

/* ----------------------------- moog ----------------------------- */
static t_class *moog_class;


typedef struct _moog
{
     t_object x_obj;
  t_pd   in2;
     t_sample x_1,x_2,x_3,x_4;
     t_sample y_1,y_2,y_3,y_4;
} t_moog;

static void moog_reset(t_moog *x)
{
	x->x_1 = x->x_2 = x->x_3 = x->x_4 = 0;
	x->y_1 = x->y_2 = x->y_3 = x->y_4 = 0;

}



static void *moog_new(t_symbol *s, int argc, t_atom *argv)
{
    if (argc > 1) post("moog~: extra arguments ignored");
    {
	t_moog *x = (t_moog *)pd_new(moog_class);
	outlet_new(&x->x_obj, &s_signal);
	inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_signal, &s_signal);
	inlet_new(&x->x_obj, &x->in2, &s_signal, &s_signal);
	moog_reset(x);
	return (x);
    }


}



static t_sample calc_k(t_sample f,t_sample k) {
  if (k>itofix(4)) k = itofix(4);
  if (k < 0) k = 0;
  if (f <= itofix(3800)) return k;
  k = k - mult(0.5,(f-idiv(itofix(3800),itofix(4300))));
  return k;
}

t_int *moog_perform(t_int *w)
{
    t_moog* x = (t_moog*) (w[1]); 
    t_sample *in1 = (t_sample *)(w[2]);
    t_sample *p = (t_sample *)(w[3]);
    t_sample *k = (t_sample *)(w[4]);

    t_sample *out = (t_sample *)(w[5]);
    int n = (int)(w[6]);
    t_sample in;
    t_sample pt,pt1;
    
    t_sample x1 = x->x_1;
    t_sample x2 = x->x_2;
    t_sample x3 = x->x_3;
    t_sample x4 = x->x_4;
    t_sample ys1 = x->y_1;
    t_sample ys2 = x->y_2;
    t_sample ys3 = x->y_3;
    t_sample ys4 = x->y_4;


   while (n--) {
     if (*p > itofix(8140)) *p = itofix(8140);
     *k = calc_k(*p,*k);
     pt =*p;
     pt1=mult((pt+1),ftofix(0.76923077));
     in = *in1++ - mult(*k,ys4);
     ys1 = mult(pt1,in) + mult(0.3,x1) - mult(pt,ys1);
     x1 = in;
     ys2 = mult(pt1,ys1) + mult(0.3,x2) - mult(pt,ys2);
     x2 = ys1;
     ys3 = mult(pt1,ys2) + mult(0.3,x3) - mult(pt,ys3);
     x3 = ys2;
     ys4 = mult(pt1,ys3) + mult(0.3,x4) - mult(pt,ys4);
     x4 = ys3;
     *out++ = ys4;
   }

   
    x->y_1 = ys1;
    x->y_2 = ys2;
    x->y_3 = ys3;
    x->y_4 = ys4;
    x->x_1 = x1;
    x->x_2 = x2;
    x->x_3 = x3;
    x->x_4 = x4;

    return (w+7);
}


#define CLIP(x)  x = ((x) > 1.0 ? (1.0) : (x))

t_int *moog_perf8(t_int *w)
{
    t_moog* x = (t_moog*) (w[1]); 
    t_sample *in1 = (t_sample *)(w[2]);
    t_sample *p = (t_sample *)(w[3]);
    t_sample *k = (t_sample *)(w[4]);
    t_sample *out = (t_sample *)(w[5]);
    int n = (int)(w[6]);

    t_sample x1 = x->x_1;
    t_sample x2 = x->x_2;
    t_sample x3 = x->x_3;
    t_sample x4 = x->x_4;
    t_sample ys1 = x->y_1;
    t_sample ys2 = x->y_2;
    t_sample ys3 = x->y_3;
    t_sample ys4 = x->y_4;
				    
    t_sample temp,temp2;
    t_sample pt,pt1;
    t_sample in;

    while (n--) {
      if (*p > itofix(8140)) *p = itofix(8140);
      *k = calc_k(*p,*k);

     pt =mult(*p, ftofix(0.01*0.0140845)) - ftofix(0.9999999f);
     pt1=mult((pt+itofix(1)),ftofix(0.76923077));
     in = *in1++ - mult(*k,ys4);
     ys1 = mult(pt1,(in + mult(ftofix(0.3),x1))) - mult(pt,ys1);
     x1 = in;
     ys2 = mult(pt1,(ys1 + mult(0.3,x2))) - mult(pt,ys2);
     x2 = ys1;
     ys3 = mult(pt1,(ys2 + mult(0.3,x3))) - mult(pt,ys3);
     x3 = ys2;
     ys4 = mult(pt1,(ys3 + mult(0.3,x4))) - mult(pt,ys4);
     x4 = ys3;
     *out++ = ys4;

      p++;k++;
    }

    x->y_1 = ys1;
    x->y_2 = ys2;
    x->y_3 = ys3;
    x->y_4 = ys4;
    x->x_1 = x1;
    x->x_2 = x2;
    x->x_3 = x3;
    x->x_4 = x4;
    
    return (w+7);
}

void dsp_add_moog(t_moog *x, t_sample *in1, t_sample *in2, t_sample *in3, t_sample *out, int n)
{
    if (n&7)
    	dsp_add(moog_perform, 6,(t_int)x, in1,in2,in3, out, n);
    else	
    	dsp_add(moog_perf8, 6,(t_int) x, in1, in2, in3, out, n);
}

static void moog_dsp(t_moog *x, t_signal **sp)
{
    dsp_add_moog(x,sp[0]->s_vec, sp[1]->s_vec, sp[2]->s_vec, sp[3]->s_vec,sp[0]->s_n);
}


void moog_tilde_setup(void)
{
    moog_class = class_new(gensym("moog~"), (t_newmethod)moog_new, 0,
    	sizeof(t_moog), 0, A_GIMME, 0);
    class_addmethod(moog_class, nullfn, gensym("signal"), 0);
    class_addmethod(moog_class, (t_method)moog_reset, gensym("reset"), 0);
    class_addmethod(moog_class, (t_method)moog_dsp, gensym("dsp"), A_NULL);
}