/* Icecast
 *
 *  This program is distributed under the GNU General Public License,
 *  version 2. A copy of this license is included with this source.
 *  At your option, this specific source file can also be distributed
 *  under the GNU GPL version 3.
 *
 * Copyright 2012,      David Richards, Mozilla Foundation,
 *                      and others (see AUTHORS for details).
 */


/* Ogg codec handler for opus streams */

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

#include <stdlib.h>
#include <string.h>
#include <ogg/ogg.h>

typedef struct source_tag source_t;

#include "format_opus.h"
#include "refbuf.h"
#include "client.h"

#define CATMODULE "format-opus"
#include "logging.h"

static void opus_codec_free (ogg_state_t *ogg_info, ogg_codec_t *codec)
{
    ogg_stream_clear (&codec->os);
    free (codec);
}


static refbuf_t *process_opus_page (ogg_state_t *ogg_info,
        ogg_codec_t *codec, ogg_page *page)
{
    refbuf_t *refbuf;

    if (codec->headers < 2)
    {
        ogg_packet packet;

        ogg_stream_pagein (&codec->os, page);
        while (ogg_stream_packetout (&codec->os, &packet) > 0)
        {
           /* first time around (normal case) yields comments */
           codec->headers++;
        }
        /* add header page to associated list */
        format_ogg_attach_header (ogg_info, page);
        return NULL;
    }
    refbuf = make_refbuf_with_page (page);
    return refbuf;
}


ogg_codec_t *initial_opus_page (format_plugin_t *plugin, ogg_page *page)
{
    ogg_state_t *ogg_info = plugin->_state;
    ogg_codec_t *codec = calloc (1, sizeof (ogg_codec_t));
    ogg_packet packet;

    ogg_stream_init (&codec->os, ogg_page_serialno (page));
    ogg_stream_pagein (&codec->os, page);

    ogg_stream_packetout (&codec->os, &packet);

    ICECAST_LOG_DEBUG("checking for opus codec");
    if (strncmp((char *)packet.packet, "OpusHead", 8) != 0)
    {
        ogg_stream_clear (&codec->os);
        free (codec);
        return NULL;
    }
    ICECAST_LOG_INFO("seen initial opus header");
    codec->process_page = process_opus_page;
    codec->codec_free = opus_codec_free;
    codec->headers = 1;
    format_ogg_attach_header (ogg_info, page);
    return codec;
}