/*****************************************************************************

 * ogg_granule.c : ogg granule functions

 *****************************************************************************

 * Copyright (C) 2008 - 2018 VideoLAN Authors and VideoLabs

 *

 * This program is free software; you can redistribute it and/or modify it

 * under the terms of the GNU Lesser General Public License as published by

 * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with this program; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.

 *****************************************************************************/

#ifdef HAVE_CONFIG_H

# include "config.h"

#endif

#ifdef HAVE_LIBVORBIS

  #include <vorbis/codec.h>

#endif

#include <ogg/ogg.h>

#include <vlc_common.h>

#include <vlc_codecs.h>

#include <vlc_es.h>

#include "ogg.h"

#include "ogg_granule.h"

/* Theora spec 7.1 */

#define THEORA_FTYPE_NOTDATA       0x80

#define THEORA_FTYPE_INTERFRAME    0x40

/* Checks if current packet matches codec keyframe */

bool Ogg_IsKeyFrame( const logical_stream_t *p_stream, const ogg_packet *p_packet )

{

    if ( p_stream->b_oggds )

    {

        return ( p_packet->bytes > 0 && p_packet->packet[0] & PACKET_IS_SYNCPOINT );

    }

    else switch ( p_stream->fmt.i_codec )

    {

        case VLC_CODEC_THEORA:

        case VLC_CODEC_DAALA: /* Same convention used in daala */

            if ( p_packet->bytes <= 0 || p_packet->packet[0] & THEORA_FTYPE_NOTDATA )

                return false;

            else

                return !( p_packet->packet[0] & THEORA_FTYPE_INTERFRAME );

        case VLC_CODEC_VP8:

            return ( ( ( p_packet->granulepos >> 3 ) & 0x07FFFFFF ) == 0 );

        case VLC_CODEC_DIRAC:

            if( p_stream->special.dirac.b_old )

                return (p_packet->granulepos & 0x3FFFFFFF) == 0;

            else

                return (p_packet->granulepos & 0xFF8000FF) == 0;

        default:

            return true;

    }

}

int64_t Ogg_GetKeyframeGranule( const logical_stream_t *p_stream, int64_t i_granule )

{

    if ( p_stream->b_oggds )

    {

           return -1; /* We have no way to know */

    }

    else switch( p_stream->fmt.i_codec )

    {

        case VLC_CODEC_THEORA:

        case VLC_CODEC_DAALA:

            return ( i_granule >> p_stream->i_granule_shift ) << p_stream->i_granule_shift;

        case VLC_CODEC_DIRAC:

            if( p_stream->special.dirac.b_old )

                return ( i_granule >> 30 ) << 30;

            else

                return ( i_granule >> 31 ) << 31;

        default:

            /* No change, that's keyframe */

            return i_granule;

    }

}

static int64_t Ogg_GranuleToSampleDelta( const logical_stream_t *p_stream, int64_t i_granule )

{

    if( p_stream->fmt.i_codec == VLC_CODEC_DIRAC && !p_stream->special.dirac.b_old )

        return (i_granule >> 9) & 0x1fff;

    else

        return -1;

}

static int64_t Ogg_GranuleToSample( const logical_stream_t *p_stream, int64_t i_granule )

{

    switch( p_stream->fmt.i_codec )

    {

        case VLC_CODEC_THEORA:

            if( p_stream->i_first_frame_index == 0 && !p_stream->b_oggds )

                i_granule++;

            /* fallthrough */

        case VLC_CODEC_DAALA:

        case VLC_CODEC_KATE:

        {

            ogg_int64_t iframe = i_granule >> p_stream->i_granule_shift;

            ogg_int64_t pframe = i_granule - ( iframe << p_stream->i_granule_shift );

            return iframe + pframe;

        }

        case VLC_CODEC_VP8:

        case VLC_CODEC_OGGSPOTS:

            return i_granule >> p_stream->i_granule_shift;

        case VLC_CODEC_DIRAC:

            if( p_stream->special.dirac.b_old )

                return (i_granule >> 30) + (i_granule & 0x3FFFFFFF);

            else

                return (i_granule >> 31);

        case VLC_CODEC_OPUS:

        case VLC_CODEC_VORBIS:

        case VLC_CODEC_SPEEX:

        case VLC_CODEC_FLAC:

            return i_granule/* - p_stream->i_pre_skip*/;

        default:

            return i_granule;

    }

}

static int64_t Ogg_ShiftPacketSample( const logical_stream_t *p_stream,

                                      int64_t i_sample, bool b_start )

{

    /* /!\ Packet Granule as sample value ! */

    /* granule always point to end time of packet

       Except with OggDS where it is reversed */

    int64_t i_endtostartoffset = 0; /* in interval # */

    if( p_stream->b_oggds )

        i_endtostartoffset = (b_start ? 0 : 1);

    else

        i_endtostartoffset = (b_start ? -1 : 0);

    if( p_stream->fmt.i_cat == VIDEO_ES )

    {

        if( p_stream->fmt.i_codec == VLC_CODEC_DIRAC ) /* points to start */

            i_sample += (p_stream->special.dirac.b_interlaced ? 1 : 2) * (i_endtostartoffset + 1);

        else

            i_sample += i_endtostartoffset * 1;

    }

    else if( p_stream->fmt.i_cat == AUDIO_ES )

    {

        if( p_stream->fmt.i_codec == VLC_CODEC_SPEEX )

        {

            i_sample += i_endtostartoffset *

                        p_stream->special.speex.i_framesize *

                        p_stream->special.speex.i_framesperpacket;

        }

        else /* we can't tell */

        {

            if( i_endtostartoffset != 0 )

                return -1;

        }

    }

    return i_sample;

}

vlc_tick_t Ogg_SampleToTime( const logical_stream_t *p_stream, int64_t i_sample, bool b_start )

{

    i_sample = Ogg_ShiftPacketSample( p_stream, i_sample, b_start );

    if( i_sample < 0 )

        return VLC_TICK_INVALID;

    date_t d = p_stream->dts;

    date_Set(&d, VLC_TICK_0);

    return date_Increment( &d, i_sample );

}

bool Ogg_GranuleIsValid( const logical_stream_t *p_stream, int64_t i_granule )

{

    /* First frame in ogm is 0 (0[header] 0[frame] -1 2 3 -1 5 ...) */

    return !( i_granule < p_stream->i_first_frame_index - !!p_stream->b_oggds );

}

vlc_tick_t Ogg_GranuleToTime( const logical_stream_t *p_stream, int64_t i_granule,

                           bool b_start, bool b_pts )

{

    if( !Ogg_GranuleIsValid( p_stream, i_granule ) )

        return VLC_TICK_INVALID;

    int64_t i_sample = Ogg_GranuleToSample( p_stream, i_granule );

    if( b_pts )

    {

        int64_t i_delta = Ogg_GranuleToSampleDelta( p_stream, i_granule );

        if( i_delta != -1 )

            i_sample += i_delta;

    }

    return Ogg_SampleToTime( p_stream, i_sample, b_start );

}