/*
  dsp_dtmf.c
  David Rowe Sep 5 2006

  This file provides an interface between Steve Underwood's DTMF test software and
  the Asterisk DSP code.  Allows sophisicated unit testing of Asterisk dsp.c signal 
  processing functions.  
*/

/*
  Copyright (C) 2006 David Rowe
 
  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.
  
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
  
  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 
*/
   
#include <sys/types.h>
#include <asterisk/frame.h>
#include <asterisk/channel.h>
#include <asterisk/logger.h>
#include <asterisk/dsp.h> /* Asterisk DTMF detector functions */
#include <tone_detect.h>  /* spandsp DTMF detector interface  */

/* dummy variables and stubs to enable dsp.c to link OK */

unsigned char __ast_lin2a[8192];
short __ast_alaw[256];
unsigned char __ast_lin2mu[16384];
short __ast_mulaw[256];
void ast_log(int level, const char *file, int line, 
	     const char *function, const char *fmt, ...)
{

}
int ast_queue_frame(struct ast_channel *chan, struct ast_frame *f)
{
  return 0;
}
void ast_frfree(struct ast_frame *fr)
{
}

char *ast_getformatname(int format)
{
  return "dummy";
}
void ast_register_file_version(const char *file, const char *version)
{
}
void ast_unregister_file_version(const char *file)
{
}
 
static struct ast_dsp   *dsp;
static int               digits;
static char              digbuf[128];

dtmf_rx_state_t *dtmf_rx_init(
  dtmf_rx_state_t  *s,
  void            (*callback)(void *user_data, const char *digits, int len),
  void            *user_data
)
{
  dsp = ast_dsp_new();
  ast_dsp_set_features(dsp,  DSP_FEATURE_DTMF_DETECT);
  digits = 0;
  *digbuf = 0;
}

void dtmf_rx_parms(dtmf_rx_state_t *s, int filter_dialtone, int twist, int reverse_twist)
{
}

int dtmf_rx(dtmf_rx_state_t *s, const int16_t *amp, int samples)
{
  struct ast_frame   af_in;
  struct ast_frame  *af_out;
  int               n;

  af_in.subclass = AST_FORMAT_SLINEAR;
  af_in.frametype = AST_FRAME_VOICE;
  af_in.data = (char*)amp;
  af_in.datalen = samples*2;

  af_out = ast_dsp_process(NULL, dsp, &af_in);
  if (af_out->frametype == AST_FRAME_DTMF) {
    digbuf[digits++] =  af_out->subclass;
  }

}

int dtmf_get(dtmf_rx_state_t *s, char *buf, int max)
{
  int dig = digits;
  
  memcpy(buf, digbuf, digits);
  digits = 0;
  *digbuf = 0;

  return dig;
}