/* -*- c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* ====================================================================
* Copyright (c) 2013 Carnegie Mellon University.  All rights 
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer. 
*
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in
*    the documentation and/or other materials provided with the
*    distribution.
*
* This work was supported in part by funding from the Defense Advanced 
* Research Projects Agency and the National Science Foundation of the 
* United States of America, and the CMU Sphinx Speech Consortium.
*
* THIS SOFTWARE IS PROVIDED BY CARNEGIE MELLON UNIVERSITY ``AS IS'' AND 
* ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY
* NOR ITS EMPLOYEES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* ====================================================================
*
*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <string.h>
#include <assert.h>

#include "sphinxbase/ckd_alloc.h"
#include "sphinxbase/err.h"

#include "fe_prespch_buf.h"

struct prespch_buf_s {
    /* saved mfcc frames */
    mfcc_t **cep_buf;
    /* saved pcm audio */
    int16 *pcm_buf;
    /* flag for pcm buffer initialization */
    int16 cep_write_ptr;
    /* read pointer for cep buffer */
    int16 cep_read_ptr;
    /* write pointer for pcm buffer */
    int16 pcm_write_ptr;
    /* frames amount in cep buffer */
    int16 num_frames_cep;
    /* frames amount in pcm buffer */
    int16 num_frames_pcm;
    /* filters amount */
    int16 num_cepstra;
    /* amount of fresh samples in frame */
    int16 num_samples;
};

prespch_buf_t *
fe_prespch_init(int num_frames, int num_cepstra, int num_samples)
{
    prespch_buf_t *prespch_buf;

    prespch_buf = (prespch_buf_t *) ckd_calloc(1, sizeof(prespch_buf_t));

    prespch_buf->num_cepstra = num_cepstra;
    prespch_buf->num_frames_cep = num_frames;
    prespch_buf->num_samples = num_samples;
    prespch_buf->num_frames_pcm = 0;
    prespch_buf->cep_write_ptr = 0;
    prespch_buf->cep_read_ptr = 0;
    prespch_buf->pcm_write_ptr = 0;

    prespch_buf->cep_buf = (mfcc_t **)
        ckd_calloc_2d(num_frames, num_cepstra,
                      sizeof(**prespch_buf->cep_buf));

    return prespch_buf;
}

void 
fe_prespch_extend_pcm(prespch_buf_t* prespch_buf, int num_frames_pcm)
{
    num_frames_pcm += prespch_buf->num_frames_cep + 1;
    if (num_frames_pcm > prespch_buf->num_frames_pcm) {
        prespch_buf->num_frames_pcm = num_frames_pcm;
        prespch_buf->pcm_buf = (int16 *) ckd_realloc(prespch_buf->pcm_buf, prespch_buf->num_frames_pcm * prespch_buf->num_samples * sizeof(int16));
    }
}

int
fe_prespch_read_cep(prespch_buf_t * prespch_buf, mfcc_t * fea)
{
    if (prespch_buf->cep_read_ptr >= prespch_buf->num_frames_cep)
        return 0;
    if (prespch_buf->cep_read_ptr >= prespch_buf->cep_write_ptr)
        return 0;
    memcpy(fea, prespch_buf->cep_buf[prespch_buf->cep_read_ptr],
           sizeof(mfcc_t) * prespch_buf->num_cepstra);
    prespch_buf->cep_read_ptr++;
    return 1;
}

void
fe_prespch_write_cep(prespch_buf_t * prespch_buf, mfcc_t * fea)
{
    assert(prespch_buf->cep_write_ptr < prespch_buf->num_frames_cep);
    memcpy(prespch_buf->cep_buf[prespch_buf->cep_write_ptr], fea,
           sizeof(mfcc_t) * prespch_buf->num_cepstra);
    prespch_buf->cep_write_ptr++;
}

void
fe_prespch_read_pcm(prespch_buf_t * prespch_buf, int16 ** samples,
                    int32 * samples_num)
{
    if (!prespch_buf->pcm_buf) {
        /* pcm prespch buffer isn't initialized yet */
        samples = NULL;
        *samples_num = 0;
        return;
    }
    *samples = prespch_buf->pcm_buf;
    *samples_num = prespch_buf->pcm_write_ptr * prespch_buf->num_samples;
    prespch_buf->pcm_write_ptr = 0;
}

void
fe_prespch_write_pcm(prespch_buf_t * prespch_buf, int16 * samples)
{
    int32 sample_ptr;

    assert(prespch_buf->pcm_write_ptr < prespch_buf->num_frames_pcm);
    sample_ptr = prespch_buf->pcm_write_ptr * prespch_buf->num_samples;
    memcpy(&prespch_buf->pcm_buf[sample_ptr], samples,
           prespch_buf->num_samples * sizeof(int16));
    prespch_buf->pcm_write_ptr++;
}

void
fe_prespch_reset_cep(prespch_buf_t * prespch_buf)
{
    prespch_buf->cep_read_ptr = 0;
    prespch_buf->cep_write_ptr = 0;
}

void
fe_prespch_reset_pcm(prespch_buf_t * prespch_buf)
{
    prespch_buf->pcm_write_ptr = 0;
}

void
fe_prespch_free(prespch_buf_t * prespch_buf)
{
    if (!prespch_buf)
	return;
    if (prespch_buf->cep_buf)
        ckd_free_2d((void **) prespch_buf->cep_buf);
    if (prespch_buf->pcm_buf)
        ckd_free(prespch_buf->pcm_buf);
    ckd_free(prespch_buf);
}

int32 
fe_prespch_ncep(prespch_buf_t * prespch_buf)
{
    return prespch_buf->cep_write_ptr - prespch_buf->cep_read_ptr;
}