/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2002 Björn Stenberg
 *
 * All files in this archive are subject to the GNU General Public License.
 * See the file COPYING in the source tree root for full license agreement.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/
#include "kernel.h"
#include "codecs.h"

#include "Tremor/ivorbisfile.h"
#include "playback.h"
#include "lib/codeclib.h"

static struct codec_api* rb;

/* Some standard functions and variables needed by Tremor */

int errno;

size_t strlen(const char *s)
{
    return(rb->strlen(s));
}

char *strcpy(char *dest, const char *src)
{
    return(rb->strcpy(dest,src));
}

char *strcat(char *dest, const char *src)
{
    return(rb->strcat(dest,src));
}

size_t read_handler(void *ptr, size_t size, size_t nmemb, void *datasource)
{
    (void)datasource;
    return rb->read_filebuf(ptr, nmemb*size);
}

int seek_handler(void *datasource, ogg_int64_t offset, int whence)
{
    /* We are not seekable at the moment */
    (void)datasource;
    (void)offset;
    (void)whence;
    return -1;
}

int close_handler(void *datasource)
{
    (void)datasource;
    return 0;
}

long tell_handler(void *datasource)
{
    (void)datasource;
    return rb->curpos;
}

#ifdef USE_IRAM
extern char iramcopy[];
extern char iramstart[];
extern char iramend[];
#endif


/* reserve the PCM buffer in the IRAM area */
static char pcmbuf[4096] IDATA_ATTR;

/* this is the codec entry point */
enum codec_status codec_start(struct codec_api* api)
{
    ov_callbacks callbacks;
    OggVorbis_File vf;
    vorbis_info* vi;

    int error;
    long n;
    int current_section;
    int eof;
#if BYTE_ORDER == BIG_ENDIAN
    int i;
    char x;
#endif

    TEST_CODEC_API(api);

    /* if you are using a global api pointer, don't forget to copy it!
       otherwise you will get lovely "I04: IllInstr" errors... :-) */
    rb = api;

#ifdef USE_IRAM
    rb->memcpy(iramstart, iramcopy, iramend-iramstart);
#endif
    
    rb->configure(CODEC_SET_FILEBUF_LIMIT, (int *)(1024*1024*2));
    rb->configure(CODEC_SET_FILEBUF_CHUNKSIZE, (int *)(1024*64));
    
    /* We need to flush reserver memory every track load. */
  next_track:
    if (codec_init(rb)) {
        return CODEC_ERROR;
    }


    /* Create a decoder instance */

    callbacks.read_func=read_handler;
    callbacks.seek_func=seek_handler;
    callbacks.tell_func=tell_handler;
    callbacks.close_func=close_handler;

    error=ov_open_callbacks(rb,&vf,NULL,0,callbacks);
    
    vi=ov_info(&vf,-1);

    if (vi==NULL) {
        // rb->splash(HZ*2, true, "Vorbis Error");
        return CODEC_ERROR;
    }
  
    eof=0;
    while (!eof) {
        /* Read host-endian signed 16 bit PCM samples */
        n=ov_read(&vf,pcmbuf,sizeof(pcmbuf),&current_section);

        if (n==0) {
            eof=1;
        }
        else if (n < 0) {
            DEBUGF("Error decoding frame\n");
        } else {
            rb->yield();
            if (rb->stop_codec || rb->reload_codec)
                break ;
        
            rb->yield();
            while (!rb->audiobuffer_insert(pcmbuf, n))
                rb->yield();

            rb->set_elapsed(ov_time_tell(&vf));

#if BYTE_ORDER == BIG_ENDIAN
            for (i=0;i<n;i+=2) { 
                x=pcmbuf[i]; pcmbuf[i]=pcmbuf[i+1]; pcmbuf[i+1]=x;
            }
#endif
        }
    }
  
    if (rb->request_next_track())
        goto next_track;
    
    return CODEC_OK;
}