#include <portaudio.h> /*    -*- c -*- */
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
#include <memory.h>
#include "ppport.h"
#include <string.h>

typedef struct {
  SV *isv;
  SV *cbfn;
  PerlInterpreter *pi;
} mybundle;

static PortAudioStream *pa_stream;
static mybundle bundle;

static int pa_callback (void *in, void *out, unsigned long nsamps,
			PaTimestamp outTime, void *user) {
  
  unsigned char *fromperl;

  mybundle *intbundle = (mybundle *) user;

  PERL_SET_CONTEXT (intbundle->pi);
 
  if (intbundle->cbfn == NULL)
    croak ("Soundzero: PA callback called, but not set to point to "
	   "any perl function.\n");
  
  { 
    dSP;
    int count;

    ENTER;
    SAVETMPS;

    PUSHMARK(sp);
    XPUSHs (sv_2mortal(newSVpvn((unsigned char *) in, nsamps)));
    PUTBACK;

    count = perl_call_sv (intbundle->cbfn, G_SCALAR);

    SPAGAIN;
    
    if (count != 1)
      croak ("Soundzero: PA callback function did not return a scalar.\n");
    
    fromperl = (unsigned char *) POPp;
    memcpy (out, fromperl, nsamps);

    PUTBACK;
    FREETMPS;
    LEAVE;
  }

  return 0;

}

MODULE = Soundzero		PACKAGE = Soundzero		

void 
pa_init (samplerate, buflen)
     double samplerate
     int buflen
     CODE:
     bundle.isv = newSVpvn (NULL, buflen);     
     bundle.pi = Perl_get_context ();
     bundle.cbfn = (SV *) NULL;
     Pa_Initialize ();
     Pa_OpenDefaultStream (&pa_stream, 1, 1, paUInt8, 
			   samplerate, buflen, 0, pa_callback, &bundle);

void 
pa_sleep (mili)
     int mili
     CODE:
     Pa_Sleep (mili);

void
pa_stop ()
     CODE:
     Pa_StopStream (pa_stream);

void
pa_start ()
     CODE:
     Pa_StartStream (pa_stream);

void
pa_close ()
    CODE:
    Pa_CloseStream (pa_stream);
    Pa_Terminate ();

void
registercb (cbname)
     SV * cbname
     CODE:
     if (bundle.cbfn == (SV *) NULL) {
       bundle.cbfn = newSVsv (cbname);
     } else {
       SvSetSV (bundle.cbfn, cbname);
     }