/*****************************************************************************
 * stream_output.c : stream output module
 *****************************************************************************
 * Copyright (C) 2002-2007 the VideoLAN team
 * $Id: 103d69089916e0c2ca6b52449beb47719c12d9b3 $
 *
 * Authors: Christophe Massiot <massiot@via.ecp.fr>
 *          Laurent Aimar <fenrir@via.ecp.fr>
 *          Eric Petit <titer@videolan.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 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 General Public License for more details.
 *
 * You should have received a copy of the GNU 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 <assert.h>

#include <vlc_common.h>

#include <stdlib.h>                                                /* free() */
#include <stdio.h>                                              /* sprintf() */
#include <string.h>

#include <vlc_sout.h>

#include "stream_output.h"

#include <vlc_meta.h>
#include <vlc_block.h>
#include <vlc_codec.h>

#include "input/input_interface.h"

#define VLC_CODEC_NULL VLC_FOURCC( 'n', 'u', 'l', 'l' )

#undef DEBUG_BUFFER
/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
static char *sout_stream_url_to_chain( bool, const char * );

/*
 * Generic MRL parser
 *
 */

typedef struct
{
    char *psz_access;
    char *psz_way;
    char *psz_name;
} mrl_t;

/* mrl_Parse: parse psz_mrl and fill p_mrl */
static int  mrl_Parse( mrl_t *p_mrl, const char *psz_mrl );
/* mrl_Clean: clean p_mrl  after a call to mrl_Parse */
static void mrl_Clean( mrl_t *p_mrl );

/*****************************************************************************
 * sout_NewInstance: creates a new stream output instance
 *****************************************************************************/
sout_instance_t *__sout_NewInstance( vlc_object_t *p_parent, const char *psz_dest )
{
    static const char typename[] = "stream output";
    sout_instance_t *p_sout;

    char *psz_chain;
    if( psz_dest && psz_dest[0] == '#' )
    {
        psz_chain = strdup( &psz_dest[1] );
    }
    else
    {
        psz_chain = sout_stream_url_to_chain(
            var_InheritBool(p_parent, "sout-display"), psz_dest );
    }
    if(!psz_chain)
        return NULL;

    /* *** Allocate descriptor *** */
    p_sout = vlc_custom_create( p_parent, sizeof( *p_sout ),
                                VLC_OBJECT_GENERIC, typename );
    if( p_sout == NULL )
        return NULL;

    msg_Dbg( p_sout, "using sout chain=`%s'", psz_chain );

    /* *** init descriptor *** */
    p_sout->psz_sout    = strdup( psz_dest );
    p_sout->p_meta      = NULL;
    p_sout->i_out_pace_nocontrol = 0;
    p_sout->p_sys       = NULL;

    vlc_mutex_init( &p_sout->lock );
    p_sout->p_stream = NULL;

    /* attach it for inherit */
    vlc_object_attach( p_sout, p_parent );

    var_Create( p_sout, "sout-mux-caching", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );

    p_sout->p_stream = sout_StreamChainNew( p_sout, psz_chain, NULL, NULL );
    if( p_sout->p_stream )
    {
        free( psz_chain );
        return p_sout;
    }

    msg_Err( p_sout, "stream chain failed for `%s'", psz_chain );
    free( psz_chain );

    FREENULL( p_sout->psz_sout );

    vlc_object_release( p_sout );
    return NULL;
}

/*****************************************************************************
 * sout_DeleteInstance: delete a previously allocated instance
 *****************************************************************************/
void sout_DeleteInstance( sout_instance_t * p_sout )
{
    /* remove the stream out chain */
    sout_StreamChainDelete( p_sout->p_stream, NULL );

    /* *** free all string *** */
    FREENULL( p_sout->psz_sout );

    /* delete meta */
    if( p_sout->p_meta )
    {
        vlc_meta_Delete( p_sout->p_meta );
    }

    vlc_mutex_destroy( &p_sout->lock );

    /* *** free structure *** */
    vlc_object_release( p_sout );
}

/*****************************************************************************
 * 
 *****************************************************************************/
void sout_UpdateStatistic( sout_instance_t *p_sout, sout_statistic_t i_type, int i_delta )
{
    if( !libvlc_stats( p_sout ) )
        return;

    /* */
    input_thread_t *p_input = vlc_object_find( p_sout, VLC_OBJECT_INPUT, FIND_PARENT );
    if( !p_input )
        return;

    int i_input_type;
    switch( i_type )
    {
    case SOUT_STATISTIC_DECODED_VIDEO:
        i_input_type = SOUT_STATISTIC_DECODED_VIDEO;
        break;
    case SOUT_STATISTIC_DECODED_AUDIO:
        i_input_type = SOUT_STATISTIC_DECODED_AUDIO;
        break;
    case SOUT_STATISTIC_DECODED_SUBTITLE:
        i_input_type = SOUT_STATISTIC_DECODED_SUBTITLE;
        break;

    case SOUT_STATISTIC_SENT_PACKET:
        i_input_type = SOUT_STATISTIC_SENT_PACKET;
        break;

    case SOUT_STATISTIC_SENT_BYTE:
        i_input_type = SOUT_STATISTIC_SENT_BYTE;
        break;

    default:
        msg_Err( p_sout, "Not yet supported statistic type %d", i_type );
        vlc_object_release( p_input );
        return;
    }

    input_UpdateStatistic( p_input, i_input_type, i_delta );

    vlc_object_release( p_input );
}
/*****************************************************************************
 * Packetizer/Input
 *****************************************************************************/
sout_packetizer_input_t *sout_InputNew( sout_instance_t *p_sout,
                                        es_format_t *p_fmt )
{
    sout_packetizer_input_t *p_input;

    /* *** create a packetizer input *** */
    p_input         = malloc( sizeof( sout_packetizer_input_t ) );
    if( !p_input )  return NULL;
    p_input->p_sout = p_sout;
    p_input->p_fmt  = p_fmt;

    msg_Dbg( p_sout, "adding a new sout input (sout_input:%p)", p_input );

    if( p_fmt->i_codec == VLC_CODEC_NULL )
    {
        vlc_object_release( p_sout );
        return p_input;
    }

    /* *** add it to the stream chain */
    vlc_mutex_lock( &p_sout->lock );
    p_input->id = p_sout->p_stream->pf_add( p_sout->p_stream, p_fmt );
    vlc_mutex_unlock( &p_sout->lock );

    if( p_input->id == NULL )
    {
        free( p_input );
        return NULL;
    }

    return( p_input );
}

/*****************************************************************************
 *
 *****************************************************************************/
int sout_InputDelete( sout_packetizer_input_t *p_input )
{
    sout_instance_t     *p_sout = p_input->p_sout;

    msg_Dbg( p_sout, "removing a sout input (sout_input:%p)", p_input );

    if( p_input->p_fmt->i_codec != VLC_CODEC_NULL )
    {
        vlc_mutex_lock( &p_sout->lock );
        p_sout->p_stream->pf_del( p_sout->p_stream, p_input->id );
        vlc_mutex_unlock( &p_sout->lock );
    }

    free( p_input );

    return( VLC_SUCCESS);
}

/*****************************************************************************
 *
 *****************************************************************************/
int sout_InputSendBuffer( sout_packetizer_input_t *p_input,
                          block_t *p_buffer )
{
    sout_instance_t     *p_sout = p_input->p_sout;
    int                 i_ret;

    if( p_input->p_fmt->i_codec == VLC_CODEC_NULL )
    {
        block_Release( p_buffer );
        return VLC_SUCCESS;
    }

    if( p_buffer->i_dts <= VLC_TS_INVALID )
    {
        msg_Warn( p_sout, "trying to send non-dated packet to stream output!");
        block_Release( p_buffer );
        return VLC_SUCCESS;
    }

    vlc_mutex_lock( &p_sout->lock );
    i_ret = p_sout->p_stream->pf_send( p_sout->p_stream,
                                       p_input->id, p_buffer );
    vlc_mutex_unlock( &p_sout->lock );

    return i_ret;
}

#undef sout_AccessOutNew
/*****************************************************************************
 * sout_AccessOutNew: allocate a new access out
 *****************************************************************************/
sout_access_out_t *sout_AccessOutNew( vlc_object_t *p_sout,
                                      const char *psz_access, const char *psz_name )
{
    static const char typename[] = "access out";
    sout_access_out_t *p_access;
    char              *psz_next;

    p_access = vlc_custom_create( p_sout, sizeof( *p_access ),
                                  VLC_OBJECT_GENERIC, typename );
    if( !p_access )
        return NULL;

    psz_next = config_ChainCreate( &p_access->psz_access, &p_access->p_cfg,
                                   psz_access );
    free( psz_next );
    p_access->psz_path   = strdup( psz_name ? psz_name : "" );
    p_access->p_sys      = NULL;
    p_access->pf_seek    = NULL;
    p_access->pf_read    = NULL;
    p_access->pf_write   = NULL;
    p_access->pf_control = NULL;
    p_access->p_module   = NULL;

    p_access->i_writes = 0;
    p_access->i_sent_bytes = 0;

    vlc_object_attach( p_access, p_sout );

    p_access->p_module   =
        module_need( p_access, "sout access", p_access->psz_access, true );

    if( !p_access->p_module )
    {
        free( p_access->psz_access );
        free( p_access->psz_path );
        vlc_object_release( p_access );
        return( NULL );
    }

    return p_access;
}
/*****************************************************************************
 * sout_AccessDelete: delete an access out
 *****************************************************************************/
void sout_AccessOutDelete( sout_access_out_t *p_access )
{
    if( p_access->p_module )
    {
        module_unneed( p_access, p_access->p_module );
    }
    free( p_access->psz_access );

    config_ChainDestroy( p_access->p_cfg );

    free( p_access->psz_path );

    vlc_object_release( p_access );
}

/*****************************************************************************
 * sout_AccessSeek:
 *****************************************************************************/
int sout_AccessOutSeek( sout_access_out_t *p_access, off_t i_pos )
{
    return p_access->pf_seek( p_access, i_pos );
}

/*****************************************************************************
 * sout_AccessRead:
 *****************************************************************************/
ssize_t sout_AccessOutRead( sout_access_out_t *p_access, block_t *p_buffer )
{
    return( p_access->pf_read ?
            p_access->pf_read( p_access, p_buffer ) : VLC_EGENERIC );
}

/*****************************************************************************
 * sout_AccessWrite:
 *****************************************************************************/
ssize_t sout_AccessOutWrite( sout_access_out_t *p_access, block_t *p_buffer )
{
#if 0
    const unsigned i_packets_gather = 30;
    p_access->i_writes++;
    p_access->i_sent_bytes += p_buffer->i_buffer;
    if( (p_access->i_writes % i_packets_gather) == 0 )
    {
        sout_UpdateStatistic( p_access->p_sout, SOUT_STATISTIC_SENT_PACKET, i_packets_gather );
        sout_UpdateStatistic( p_access->p_sout, SOUT_STATISTIC_SENT_BYTE, p_access->i_sent_bytes );
        p_access->i_sent_bytes = 0;
    }
#endif
    return p_access->pf_write( p_access, p_buffer );
}

/**
 * sout_AccessOutControl
 */
int sout_AccessOutControl (sout_access_out_t *access, int query, ...)
{
    va_list ap;
    int ret;

    va_start (ap, query);
    if (access->pf_control)
        ret = access->pf_control (access, query, ap);
    else
        ret = VLC_EGENERIC;
    va_end (ap);
    return ret;
}

/*****************************************************************************
 * sout_MuxNew: create a new mux
 *****************************************************************************/
sout_mux_t * sout_MuxNew( sout_instance_t *p_sout, const char *psz_mux,
                          sout_access_out_t *p_access )
{
    static const char typename[] = "mux";
    sout_mux_t *p_mux;
    char       *psz_next;

    p_mux = vlc_custom_create( p_sout, sizeof( *p_mux ), VLC_OBJECT_GENERIC,
                               typename);
    if( p_mux == NULL )
        return NULL;

    p_mux->p_sout = p_sout;
    psz_next = config_ChainCreate( &p_mux->psz_mux, &p_mux->p_cfg, psz_mux );
    free( psz_next );

    p_mux->p_access     = p_access;
    p_mux->pf_control   = NULL;
    p_mux->pf_addstream = NULL;
    p_mux->pf_delstream = NULL;
    p_mux->pf_mux       = NULL;
    p_mux->i_nb_inputs  = 0;
    p_mux->pp_inputs    = NULL;

    p_mux->p_sys        = NULL;
    p_mux->p_module     = NULL;

    p_mux->b_add_stream_any_time = false;
    p_mux->b_waiting_stream = true;
    p_mux->i_add_stream_start = -1;

    vlc_object_attach( p_mux, p_sout );

    p_mux->p_module =
        module_need( p_mux, "sout mux", p_mux->psz_mux, true );

    if( p_mux->p_module == NULL )
    {
        FREENULL( p_mux->psz_mux );

        vlc_object_release( p_mux );
        return NULL;
    }

    /* *** probe mux capacity *** */
    if( p_mux->pf_control )
    {
        int b_answer = false;

        if( sout_MuxControl( p_mux, MUX_CAN_ADD_STREAM_WHILE_MUXING,
                             &b_answer ) )
        {
            b_answer = false;
        }

        if( b_answer )
        {
            msg_Dbg( p_sout, "muxer support adding stream at any time" );
            p_mux->b_add_stream_any_time = true;
            p_mux->b_waiting_stream = false;

            /* If we control the output pace then it's better to wait before
             * starting muxing (generates better streams/files). */
            if( !p_sout->i_out_pace_nocontrol )
            {
                b_answer = true;
            }
            else if( sout_MuxControl( p_mux, MUX_GET_ADD_STREAM_WAIT,
                                      &b_answer ) )
            {
                b_answer = false;
            }

            if( b_answer )
            {
                msg_Dbg( p_sout, "muxer prefers to wait for all ES before "
                         "starting to mux" );
                p_mux->b_waiting_stream = true;
            }
        }
    }

    return p_mux;
}

/*****************************************************************************
 * sout_MuxDelete:
 *****************************************************************************/
void sout_MuxDelete( sout_mux_t *p_mux )
{
    if( p_mux->p_module )
    {
        module_unneed( p_mux, p_mux->p_module );
    }
    free( p_mux->psz_mux );

    config_ChainDestroy( p_mux->p_cfg );

    vlc_object_release( p_mux );
}

/*****************************************************************************
 * sout_MuxAddStream:
 *****************************************************************************/
sout_input_t *sout_MuxAddStream( sout_mux_t *p_mux, es_format_t *p_fmt )
{
    sout_input_t *p_input;

    if( !p_mux->b_add_stream_any_time && !p_mux->b_waiting_stream )
    {
        msg_Err( p_mux, "cannot add a new stream (unsupported while muxing "
                        "to this format). You can try increasing sout-mux-caching value" );
        return NULL;
    }

    msg_Dbg( p_mux, "adding a new input" );

    /* create a new sout input */
    p_input = malloc( sizeof( sout_input_t ) );
    if( !p_input )
        return NULL;
    p_input->p_sout = p_mux->p_sout;
    p_input->p_fmt  = p_fmt;
    p_input->p_fifo = block_FifoNew();
    p_input->p_sys  = NULL;

    TAB_APPEND( p_mux->i_nb_inputs, p_mux->pp_inputs, p_input );
    if( p_mux->pf_addstream( p_mux, p_input ) < 0 )
    {
        msg_Err( p_mux, "cannot add this stream" );
        TAB_REMOVE( p_mux->i_nb_inputs, p_mux->pp_inputs, p_input );
        block_FifoRelease( p_input->p_fifo );
        free( p_input );
        return NULL;
    }

    return p_input;
}

/*****************************************************************************
 * sout_MuxDeleteStream:
 *****************************************************************************/
void sout_MuxDeleteStream( sout_mux_t *p_mux, sout_input_t *p_input )
{
    int i_index;

    if( p_mux->b_waiting_stream
     && block_FifoCount( p_input->p_fifo ) > 0 )
    {
        /* We stop waiting, and call the muxer for taking care of the data
         * before we remove this es */
        p_mux->b_waiting_stream = false;
        p_mux->pf_mux( p_mux );
    }

    TAB_FIND( p_mux->i_nb_inputs, p_mux->pp_inputs, p_input, i_index );
    if( i_index >= 0 )
    {
        if( p_mux->pf_delstream( p_mux, p_input ) < 0 )
        {
            msg_Err( p_mux, "cannot delete this stream from mux" );
        }

        /* remove the entry */
        TAB_REMOVE( p_mux->i_nb_inputs, p_mux->pp_inputs, p_input );

        if( p_mux->i_nb_inputs == 0 )
        {
            msg_Warn( p_mux, "no more input streams for this mux" );
        }

        block_FifoRelease( p_input->p_fifo );
        free( p_input );
    }
}

/*****************************************************************************
 * sout_MuxSendBuffer:
 *****************************************************************************/
void sout_MuxSendBuffer( sout_mux_t *p_mux, sout_input_t *p_input,
                         block_t *p_buffer )
{
    block_FifoPut( p_input->p_fifo, p_buffer );

    if( p_mux->p_sout->i_out_pace_nocontrol )
    {
        mtime_t current_date = mdate();
        if ( current_date > p_buffer->i_dts )
            msg_Warn( p_mux, "late buffer for mux input (%"PRId64")",
                      current_date - p_buffer->i_dts );
    }

    if( p_mux->b_waiting_stream )
    {
        const int64_t i_caching = var_GetInteger( p_mux->p_sout, "sout-mux-caching" ) * INT64_C(1000);

        if( p_mux->i_add_stream_start < 0 )
            p_mux->i_add_stream_start = p_buffer->i_dts;

        /* Wait until we have enought data before muxing */
        if( p_mux->i_add_stream_start < 0 ||
            p_buffer->i_dts < p_mux->i_add_stream_start + i_caching )
            return;
        p_mux->b_waiting_stream = false;
    }
    p_mux->pf_mux( p_mux );
}


/*****************************************************************************
 * sout_MuxGetStream: find stream to be muxed
 *****************************************************************************/
int sout_MuxGetStream( sout_mux_t *p_mux, int i_blocks, mtime_t *pi_dts )
{
    mtime_t i_dts = 0;
    int     i_stream = -1;

    for( int i = 0; i < p_mux->i_nb_inputs; i++ )
    {
        sout_input_t *p_input = p_mux->pp_inputs[i];
        block_t *p_data;

        if( block_FifoCount( p_input->p_fifo ) < i_blocks )
        {
            if( p_input->p_fmt->i_cat != SPU_ES )
            {
                return -1;
            }
            /* FIXME: SPU muxing */
            continue;
        }

        p_data = block_FifoShow( p_input->p_fifo );
        if( i_stream < 0 || p_data->i_dts < i_dts )
        {
            i_stream = i;
            i_dts    = p_data->i_dts;
        }
    }

    if( pi_dts ) *pi_dts = i_dts;

    return i_stream;
}


/*****************************************************************************
 *
 *****************************************************************************/
static int mrl_Parse( mrl_t *p_mrl, const char *psz_mrl )
{
    char * psz_dup = strdup( psz_mrl );
    char * psz_parser = psz_dup;
    const char * psz_access;
    const char * psz_way;
    char * psz_name;

    /* *** first parse psz_dest */
    while( *psz_parser && *psz_parser != ':' )
    {
        if( *psz_parser == '{' )
        {
            while( *psz_parser && *psz_parser != '}' )
            {
                psz_parser++;
            }
            if( *psz_parser )
            {
                psz_parser++;
            }
        }
        else
        {
            psz_parser++;
        }
    }
#if defined( WIN32 ) || defined( UNDER_CE )
    if( psz_parser - psz_dup == 1 )
    {
        /* msg_Warn( p_sout, "drive letter %c: found in source string",
                          *psz_dup ) ; */
        psz_parser = "";
    }
#endif

    if( !*psz_parser )
    {
        psz_access = psz_way = "";
        psz_name = psz_dup;
    }
    else
    {
        *psz_parser++ = '\0';

        /* let's skip '//' */
        if( psz_parser[0] == '/' && psz_parser[1] == '/' )
        {
            psz_parser += 2 ;
        }

        psz_name = psz_parser ;

        /* Come back to parse the access and mux plug-ins */
        psz_parser = psz_dup;

        if( !*psz_parser )
        {
            /* No access */
            psz_access = "";
        }
        else if( *psz_parser == '/' )
        {
            /* No access */
            psz_access = "";
            psz_parser++;
        }
        else
        {
            psz_access = psz_parser;

            while( *psz_parser && *psz_parser != '/' )
            {
                if( *psz_parser == '{' )
                {
                    while( *psz_parser && *psz_parser != '}' )
                    {
                        psz_parser++;
                    }
                    if( *psz_parser )
                    {
                        psz_parser++;
                    }
                }
                else
                {
                    psz_parser++;
                }
            }

            if( *psz_parser == '/' )
            {
                *psz_parser++ = '\0';
            }
        }

        if( !*psz_parser )
        {
            /* No mux */
            psz_way = "";
        }
        else
        {
            psz_way = psz_parser;
        }
    }

    p_mrl->psz_access = strdup( psz_access );
    p_mrl->psz_way    = strdup( psz_way );
    p_mrl->psz_name   = strdup( psz_name );

    free( psz_dup );
    return( VLC_SUCCESS );
}


/* mrl_Clean: clean p_mrl  after a call to mrl_Parse */
static void mrl_Clean( mrl_t *p_mrl )
{
    FREENULL( p_mrl->psz_access );
    FREENULL( p_mrl->psz_way );
    FREENULL( p_mrl->psz_name );
}


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

/* Destroy a "stream_out" module */
static void sout_StreamDelete( sout_stream_t *p_stream )
{
    msg_Dbg( p_stream, "destroying chain... (name=%s)", p_stream->psz_name );

    if( p_stream->p_module ) module_unneed( p_stream, p_stream->p_module );

    FREENULL( p_stream->psz_name );

    config_ChainDestroy( p_stream->p_cfg );

    msg_Dbg( p_stream, "destroying chain done" );
    vlc_object_release( p_stream );
}

/* Destroy a "stream_out" modules chain
 *
 * p_first is the first module to be destroyed in the chain
 * p_last is the last module to be destroyed
 *  if NULL, all modules are destroyed
 *  if not NULL, modules following it must be destroyed separately
 */
void sout_StreamChainDelete(sout_stream_t *p_first, sout_stream_t *p_last)
{
    while(p_first != NULL)
    {
        sout_stream_t *p_next = p_first->p_next;

        sout_StreamDelete(p_first);
        if(p_first == p_last)
           break;
        p_first = p_next;
    }
}

/* Create a "stream_out" module, which may forward its ES to p_next module */
/*
 * XXX name and p_cfg are used (-> do NOT free them)
 */
static sout_stream_t *sout_StreamNew( sout_instance_t *p_sout, char *psz_name,
                               config_chain_t *p_cfg, sout_stream_t *p_next)
{
    static const char typename[] = "stream out";
    sout_stream_t *p_stream;

    assert(psz_name);

    p_stream = vlc_custom_create( p_sout, sizeof( *p_stream ),
                                  VLC_OBJECT_GENERIC, typename );
    if( !p_stream )
        return NULL;

    p_stream->p_sout   = p_sout;
    p_stream->p_sys    = NULL;
    p_stream->psz_name = psz_name;
    p_stream->p_cfg    = p_cfg;
    p_stream->p_next   = p_next;

    msg_Dbg( p_sout, "stream=`%s'", p_stream->psz_name );

    vlc_object_attach( p_stream, p_sout );

    p_stream->p_module =
        module_need( p_stream, "sout stream", p_stream->psz_name, true );

    if( !p_stream->p_module )
    {
        /* those must be freed by the caller if creation failed */
        p_stream->psz_name = NULL;
        p_stream->p_cfg = NULL;

        sout_StreamDelete( p_stream );
        return NULL;
    }

    return p_stream;
}

/* Creates a complete "stream_out" modules chain
 *
 *  chain format: module1{option=*:option=*}[:module2{option=*:...}]
 *
 *  The modules are created starting from the last one and linked together
 *  A pointer to the last module created is stored if pp_last isn't NULL, to
 *  make sure sout_StreamChainDelete doesn't delete modules created in another
 *  place.
 *
 *  Returns a pointer to the first module.
 */
sout_stream_t *sout_StreamChainNew(sout_instance_t *p_sout, char *psz_chain,
                                sout_stream_t *p_next, sout_stream_t **pp_last)
{
    if(!psz_chain || !*psz_chain)
    {
        if(pp_last) *pp_last = NULL;
        return p_next;
    }

    char *psz_parser = strdup(psz_chain);
    if(!psz_parser)
        return NULL;

    vlc_array_t cfg, name;
    vlc_array_init(&cfg);
    vlc_array_init(&name);

    /* parse chain */
    while(psz_parser)
    {
        config_chain_t *p_cfg;
        char *psz_name;
        psz_chain = config_ChainCreate( &psz_name, &p_cfg, psz_parser );
        free( psz_parser );
        psz_parser = psz_chain;

        vlc_array_append(&cfg, p_cfg);
        vlc_array_append(&name, psz_name);
    }

    int i = vlc_array_count(&name);
    vlc_array_t module;
    vlc_array_init(&module);
    while(i--)
    {
        p_next = sout_StreamNew( p_sout, vlc_array_item_at_index(&name, i),
            vlc_array_item_at_index(&cfg, i), p_next);

        if(!p_next)
            goto error;

        if(i == vlc_array_count(&name) - 1 && pp_last)
            *pp_last = p_next;   /* last module created in the chain */

        vlc_array_append(&module, p_next);
    }

    vlc_array_clear(&name);
    vlc_array_clear(&cfg);
    vlc_array_clear(&module);

    return p_next;

error:

    i++;    /* last module couldn't be created */

    /* destroy all modules created, starting with the last one */
    int modules = vlc_array_count(&module);
    while(modules--)
        sout_StreamDelete(vlc_array_item_at_index(&module, modules));
    vlc_array_clear(&module);

    /* then destroy all names and config which weren't destroyed by
     * sout_StreamDelete */
    while(i--)
    {
        free(vlc_array_item_at_index(&name, i));
        config_ChainDestroy(vlc_array_item_at_index(&cfg, i));
    }
    vlc_array_clear(&name);
    vlc_array_clear(&cfg);

    return NULL;
}

static char *sout_stream_url_to_chain( bool b_sout_display,
                                       const char *psz_url )
{
    mrl_t       mrl;
    char        *psz_chain;

    mrl_Parse( &mrl, psz_url );

    /* Check if the URLs goes to #rtp - otherwise we'll use #standard */
    static const char rtplist[] = "dccp\0sctp\0tcp\0udplite\0";
    for (const char *a = rtplist; *a; a += strlen (a) + 1)
        if (strcmp (a, mrl.psz_access) == 0)
            goto rtp;

    if (strcmp (mrl.psz_access, "rtp") == 0)
    {
        char *port;
        /* For historical reasons, rtp:// means RTP over UDP */
        strcpy (mrl.psz_access, "udp");
rtp:
        if (mrl.psz_name[0] == '[')
        {
            port = strstr (mrl.psz_name, "]:");
            if (port != NULL)
                port++;
        }
        else
            port = strchr (mrl.psz_name, ':');
        if (port != NULL)
            *port++ = '\0'; /* erase ':' */

        if (asprintf (&psz_chain,
                      "rtp{mux=\"%s\",proto=\"%s\",dst=\"%s%s%s\"}",
                      mrl.psz_way, mrl.psz_access, mrl.psz_name,
                      port ? "\",port=\"" : "", port ? port : "") == -1)
            psz_chain = NULL;
    }
    else
    {
        /* Convert the URL to a basic standard sout chain */
        if (asprintf (&psz_chain,
                      "standard{mux=\"%s\",access=\"%s\",dst=\"%s\"}",
                      mrl.psz_way, mrl.psz_access, mrl.psz_name) == -1)
            psz_chain = NULL;
    }

    /* Duplicate and wrap if sout-display is on */
    if (psz_chain && b_sout_display)
    {
        char *tmp;
        if (asprintf (&tmp, "duplicate{dst=display,dst=%s}", psz_chain) == -1)
            tmp = NULL;
        free (psz_chain);
        psz_chain = tmp;
    }

    mrl_Clean( &mrl );
    return psz_chain;
}

#undef sout_EncoderCreate
encoder_t *sout_EncoderCreate( vlc_object_t *p_this )
{
    static const char type[] = "encoder";
    return vlc_custom_create( p_this, sizeof( encoder_t ), VLC_OBJECT_GENERIC,
                              type );
}
