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

 * rawdv.c : raw DV input module for vlc

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

 * Copyright (C) 2001-2007 VLC authors and VideoLAN

 *

 * Authors: Gildas Bazin <gbazin@netcourrier.com>

 *          Paul Corke <paul dot corke at datatote dot co dot uk>

 *

 * 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.

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

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

 * Preamble

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

#ifdef HAVE_CONFIG_H

# include "config.h"

#endif

#include <vlc_common.h>

#include <vlc_plugin.h>

#include <vlc_demux.h>

#include "rawdv.h"

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

 * Module descriptor

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

#define HURRYUP_TEXT N_( "Hurry up" )

#define HURRYUP_LONGTEXT N_( "The demuxer will advance timestamps if the " \

                "input can't keep up with the rate." )

static int  Open ( vlc_object_t * );

static void Close( vlc_object_t * );

vlc_module_begin ()

    set_shortname( "DV" )

    set_description( N_("DV (Digital Video) demuxer") )

    set_capability( "demux", 0 )

    set_subcategory( SUBCAT_INPUT_DEMUX )

    add_bool( "rawdv-hurry-up", false, HURRYUP_TEXT, HURRYUP_LONGTEXT )

    set_callbacks( Open, Close )

    /* It isn't easy to recognize a raw DV stream. The chances that we'll

     * mistake a stream from another type for a raw DV stream are too high, so

     * we'll rely on the file extension to trigger this demux. Alternatively,

     * it is possible to force this demux. */

    add_shortcut( "rawdv" )

    add_file_extension("dv")

vlc_module_end ()

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

 A little bit of background information (copied over from libdv glossary).

 - DIF block: A block of 80 bytes. This is the basic data framing unit of the

       DVC tape format, analogous to sectors of hard disc.

 - Video Section: Each DIF sequence contains a video section, consisting of

       135 DIF blocks, which are further subdivided into Video Segments.

 - Video Segment: A video segment consists of 5 DIF blocks, each corresponding

       to a single compressed macroblock.

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

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

 * Definitions of structures used by this plugin

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

typedef struct {

    int8_t sct;      /* Section type (header,subcode,aux,audio,video) */

    int8_t dsn;      /* DIF sequence number (0-12) */

    int    fsc;      /* First (0)/Second channel (1) */

    int8_t dbn;      /* DIF block number (0-134) */

} dv_id_t;

typedef struct {

    int    dsf;      /* DIF sequence flag: 525/60 (0) or 625,50 (1) */

    int8_t apt;

    int    tf1;

    int8_t ap1;

    int    tf2;

    int8_t ap2;

    int    tf3;

    int8_t ap3;

} dv_header_t;

typedef struct

{

    int    frame_size;

    es_out_id_t *p_es_video;

    es_format_t  fmt_video;

    es_out_id_t *p_es_audio;

    es_format_t  fmt_audio;

    int    i_dsf;

    double f_rate;

    int    i_bitrate;

    /* program clock reference (in units of 90kHz) */

    vlc_tick_t i_pcr;

    bool b_hurry_up;

} demux_sys_t;

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

 * Local prototypes

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

static int Demux( demux_t * );

static int Control( demux_t *, int i_query, va_list args );

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

 * Open: initializes raw DV demux structures

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

static int Open( vlc_object_t * p_this )

{

    demux_t     *p_demux = (demux_t*)p_this;

    demux_sys_t *p_sys;

    const uint8_t *p_peek, *p_peek_backup;

    uint32_t    i_dword;

    dv_header_t dv_header;

    dv_id_t     dv_id;

    if( vlc_stream_Peek( p_demux->s, &p_peek, DV_PAL_FRAME_SIZE ) <

        DV_NTSC_FRAME_SIZE )

        return VLC_EGENERIC;

    p_peek_backup = p_peek;

    /* fill in the dv_id_t structure */

    i_dword = GetDWBE( p_peek ); p_peek += 4;

    dv_id.sct = i_dword >> (32 - 3);

    i_dword <<= 8;

    dv_id.dsn = i_dword >> (32 - 4);

    i_dword <<= 4;

    dv_id.fsc = i_dword >> (32 - 1);

    i_dword <<= 4;

    dv_id.dbn = i_dword >> (32 - 8);

    i_dword <<= 8;

    if( dv_id.sct != 0 )

    {

        msg_Warn( p_demux, "not a raw DV stream header" );

        return VLC_EGENERIC;

    }

    /* fill in the dv_header_t structure */

    dv_header.dsf = i_dword >> (32 - 1);

    i_dword <<= 1;

    if( i_dword >> (32 - 1) ) /* incorrect bit */

    {

        msg_Warn( p_demux, "incorrect bit" );

        return VLC_EGENERIC;

    }

    i_dword = GetDWBE( p_peek ); p_peek += 4;

    i_dword <<= 5;

    dv_header.apt = i_dword >> (32 - 3);

    i_dword <<= 3;

    dv_header.tf1 = i_dword >> (32 - 1);

    i_dword <<= 5;

    dv_header.ap1 = i_dword >> (32 - 3);

    i_dword <<= 3;

    dv_header.tf2 = i_dword >> (32 - 1);

    i_dword <<= 5;

    dv_header.ap2 = i_dword >> (32 - 3);

    i_dword <<= 3;

    dv_header.tf3 = i_dword >> (32 - 1);

    i_dword <<= 5;

    dv_header.ap3 = i_dword >> (32 - 3);

    p_peek += 72;                                  /* skip rest of DIF block */

    p_demux->p_sys      = p_sys = malloc( sizeof( demux_sys_t ) );

    if( !p_sys )

        return VLC_ENOMEM;

    p_sys->b_hurry_up = var_CreateGetBool( p_demux, "rawdv-hurry-up" );

    msg_Dbg( p_demux, "Realtime DV Source: %s", (p_sys->b_hurry_up)?"Yes":"No" );

    p_sys->i_dsf = dv_header.dsf;

    p_sys->frame_size = dv_header.dsf ? DV_PAL_FRAME_SIZE

                                      : DV_NTSC_FRAME_SIZE;

    p_sys->f_rate = dv_header.dsf ? 25 : 29.97;

    p_sys->i_pcr = 0;

    p_sys->p_es_video = NULL;

    p_sys->p_es_audio = NULL;

    p_sys->i_bitrate = 0;

    es_format_Init( &p_sys->fmt_video, VIDEO_ES, VLC_CODEC_DV );

    p_sys->fmt_video.video.i_width = 720;

    p_sys->fmt_video.video.i_height= dv_header.dsf ? 576 : 480;

    p_sys->fmt_video.video.i_visible_width = p_sys->fmt_video.video.i_width;

    p_sys->fmt_video.video.i_visible_height = p_sys->fmt_video.video.i_height;

    p_sys->p_es_video = es_out_Add( p_demux->out, &p_sys->fmt_video );

    /* Audio stuff */

    p_peek = p_peek_backup + 80*6+80*16*3 + 3; /* beginning of AAUX pack */

    if( *p_peek == 0x50 )

    {

        dv_get_audio_format( &p_sys->fmt_audio, &p_peek[1] );

        p_sys->p_es_audio = es_out_Add( p_demux->out, &p_sys->fmt_audio );

    }

    p_demux->pf_demux   = Demux;

    p_demux->pf_control = Control;

    return VLC_SUCCESS;

}

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

 * Close: frees unused data

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

static void Close( vlc_object_t *p_this )

{

    demux_t     *p_demux = (demux_t*)p_this;

    demux_sys_t *p_sys  = p_demux->p_sys;

    var_Destroy( p_demux, "rawdv-hurry-up");

    free( p_sys );

}

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

 * Demux: reads and demuxes data packets

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

 * Returns -1 in case of error, 0 in case of EOF, 1 otherwise

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

static int Demux( demux_t *p_demux )

{

    demux_sys_t *p_sys  = p_demux->p_sys;

    block_t     *p_block;

    if( p_sys->b_hurry_up )

    {

         /* 3 frames */

        p_sys->i_pcr = vlc_tick_now() + (p_sys->i_dsf ? VLC_TICK_FROM_MS(120) : VLC_TICK_FROM_MS(90));

    }

    /* Call the pace control */

    es_out_SetPCR( p_demux->out, VLC_TICK_0 + p_sys->i_pcr );

    p_block = vlc_stream_Block( p_demux->s, p_sys->frame_size );

    if( p_block == NULL )

        return VLC_DEMUXER_EOF;

    p_block->i_dts =

    p_block->i_pts = VLC_TICK_0 + p_sys->i_pcr;

    if( likely(p_sys->p_es_audio) )

    {

        bool b_audio = false;

        es_out_Control( p_demux->out, ES_OUT_GET_ES_STATE,

                        p_sys->p_es_audio, &b_audio );

        if( b_audio )

        {

            block_t *p_audio_block = dv_extract_audio( p_block );

            if( p_audio_block )

                es_out_Send( p_demux->out, p_sys->p_es_audio, p_audio_block );

        }

    }

    if( likely(p_sys->p_es_video) )

        es_out_Send( p_demux->out, p_sys->p_es_video, p_block );

    else

        block_Release( p_block );

    if( !p_sys->b_hurry_up )

    {

        p_sys->i_pcr += vlc_tick_rate_duration( p_sys->f_rate );

    }

    return VLC_DEMUXER_SUCCESS;

}

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

 * Control:

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

static int Control( demux_t *p_demux, int i_query, va_list args )

{

    demux_sys_t *p_sys  = p_demux->p_sys;

    /* XXX: DEMUX_SET_TIME is precise here */

    return demux_vaControlHelper( p_demux->s,

                                   0, -1,

                                   p_sys->frame_size * p_sys->f_rate * 8,

                                   p_sys->frame_size, i_query, args );

}