#include <stdio.h>

#include "zexy.h"

#ifdef NT
#pragma warning( disable : 4244 )
#pragma warning( disable : 4305 )
#endif

/* ------------------------ dspobj~ ----------------------------- */

/* datendefinition */

static t_class *dfreq_class;

typedef struct _dfreq
{
  t_object x_obj;

  t_float freq;  /*freqenz variable */
  t_float alt;
  float sampcount;
  t_float sr;
} t_dfreq;


static t_int *dfreq_perform(t_int *w)
{
  t_float *in = (t_float *)(w[1]);
  t_float *out = (t_float *)(w[2]);
  int n = (int)(w[3]);
  t_dfreq *x = (t_dfreq *) w[4];

  t_float a = x->alt, c = x->sampcount;
  t_float freq = x->freq, sr=x->sr;

  t_float delta_inv;

  while (n--) {

    if( (a * *in) < 0 && (a < *in)){

	/* interpolate for real zerocross */
	  delta_inv = 1./(*in-a);
      if(c > 0.0)
		  freq = sr / ((t_float) c + a*delta_inv);
      else
		  freq = sr;

      c = *in*delta_inv; /*rest of time */
    };

    a = *in;
    in++;
    c += 1.0;
    *out++ = freq;
  }

  x->alt = a;  
  x->sampcount = c;
  x->freq=freq;

  return (w+5);
}

static void dfreq_dsp(t_dfreq *x, t_signal **sp)
{
    dsp_add(dfreq_perform, 4, sp[0]->s_vec, sp[1]->s_vec, sp[0]->s_n,x);
}



static void *dfreq_new()
{
  t_dfreq *x = (t_dfreq *)pd_new(dfreq_class);
  outlet_new(&x->x_obj, gensym("signal"));

  x->sr = sys_getsr();

  return (x);
}

static void helper(void)
{
	post("\n%c dfreq~\t :: pitch-detector that counts zero-crossings", HEARTSYMBOL);
	post("\noutputs a frequency estimate as a stream~ that will be updated every zero-X");
	post("\ncreation::\t'dfreq~': that's all");
}


void z_dfreq_setup(void)
{
    dfreq_class = class_new(gensym("dfreq~"), (t_newmethod)dfreq_new, 0,
    	sizeof(t_dfreq), 0, A_DEFFLOAT, 0);
    class_addmethod(dfreq_class, nullfn, gensym("signal"), 0);
    class_addmethod(dfreq_class, (t_method)dfreq_dsp, gensym("dsp"), 0);

	class_addmethod(dfreq_class, (t_method)helper, gensym("help"), 0);
	class_sethelpsymbol(dfreq_class, gensym("zexy/dfreq~"));
}