/*****************************************************************************
 * udp.c: raw UDP input module
 *****************************************************************************
 * Copyright (C) 2001-2005 the VideoLAN team
 * Copyright (C) 2007 Remi Denis-Courmont
 * $Id: b1032ec235a134729fa77e59e9681b868e03e41b $
 *
 * Authors: Christophe Massiot <massiot@via.ecp.fr>
 *          Tristan Leteurtre <tooney@via.ecp.fr>
 *          Laurent Aimar <fenrir@via.ecp.fr>
 *          Jean-Paul Saman <jpsaman #_at_# m2x dot nl>
 *          Remi Denis-Courmont
 *
 * Reviewed: 23 October 2003, Jean-Paul Saman <jpsaman _at_ videolan _dot_ 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 <vlc_common.h>
#include <vlc_plugin.h>
#include <vlc_access.h>
#include <vlc_network.h>

#define MTU 65535

/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
#define CACHING_TEXT N_("Caching value in ms")
#define CACHING_LONGTEXT N_( \
    "Caching value for UDP streams. This " \
    "value should be set in milliseconds." )

static int  Open ( vlc_object_t * );
static void Close( vlc_object_t * );

vlc_module_begin ()
    set_shortname( N_("UDP" ) )
    set_description( N_("UDP input") )
    set_category( CAT_INPUT )
    set_subcategory( SUBCAT_INPUT_ACCESS )

    add_integer( "udp-caching", DEFAULT_PTS_DELAY / 1000, NULL, CACHING_TEXT,
                 CACHING_LONGTEXT, true );
    add_obsolete_integer( "rtp-late" )
    add_obsolete_bool( "udp-auto-mtu" )

    set_capability( "access", 0 )
    add_shortcut( "udp" )
    add_shortcut( "udpstream" )
    add_shortcut( "udp4" )
    add_shortcut( "udp6" )

    set_callbacks( Open, Close )
vlc_module_end ()

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
#define RTP_HEADER_LEN 12

static block_t *BlockUDP( access_t * );
static int Control( access_t *, int, va_list );

/*****************************************************************************
 * Open: open the socket
 *****************************************************************************/
static int Open( vlc_object_t *p_this )
{
    access_t     *p_access = (access_t*)p_this;

    char *psz_name = strdup( p_access->psz_path );
    char *psz_parser;
    const char *psz_server_addr, *psz_bind_addr = "";
    int  i_bind_port, i_server_port = 0;
    int fam = AF_UNSPEC;
    int fd;

    /* Set up p_access */
    access_InitFields( p_access );
    ACCESS_SET_CALLBACKS( NULL, BlockUDP, Control, NULL );

    if (strlen (p_access->psz_access) > 0)
    {
        switch (p_access->psz_access[strlen (p_access->psz_access) - 1])
        {
            case '4':
                fam = AF_INET;
                break;

            case '6':
                fam = AF_INET6;
                break;
        }
    }

    i_bind_port = var_CreateGetInteger( p_access, "server-port" );

    /* Parse psz_name syntax :
     * [serveraddr[:serverport]][@[bindaddr]:[bindport]] */
    psz_parser = strchr( psz_name, '@' );
    if( psz_parser != NULL )
    {
        /* Found bind address and/or bind port */
        *psz_parser++ = '\0';
        psz_bind_addr = psz_parser;

        if( psz_bind_addr[0] == '[' )
            /* skips bracket'd IPv6 address */
            psz_parser = strchr( psz_parser, ']' );

        if( psz_parser != NULL )
        {
            psz_parser = strchr( psz_parser, ':' );
            if( psz_parser != NULL )
            {
                *psz_parser++ = '\0';
                i_bind_port = atoi( psz_parser );
            }
        }
    }

    psz_server_addr = psz_name;
    psz_parser = ( psz_server_addr[0] == '[' )
        ? strchr( psz_name, ']' ) /* skips bracket'd IPv6 address */
        : psz_name;

    if( psz_parser != NULL )
    {
        psz_parser = strchr( psz_parser, ':' );
        if( psz_parser != NULL )
        {
            *psz_parser++ = '\0';
            i_server_port = atoi( psz_parser );
        }
    }

    msg_Dbg( p_access, "opening server=%s:%d local=%s:%d",
             psz_server_addr, i_server_port, psz_bind_addr, i_bind_port );

    fd = net_OpenDgram( p_access, psz_bind_addr, i_bind_port,
                        psz_server_addr, i_server_port, fam, IPPROTO_UDP );
    free (psz_name);
    if( fd == -1 )
    {
        msg_Err( p_access, "cannot open socket" );
        return VLC_EGENERIC;
    }
    p_access->p_sys = (void *)(intptr_t)fd;

    /* Update default_pts to a suitable value for udp access */
    var_Create( p_access, "udp-caching", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
    return VLC_SUCCESS;
}

/*****************************************************************************
 * Close: free unused data structures
 *****************************************************************************/
static void Close( vlc_object_t *p_this )
{
    access_t     *p_access = (access_t*)p_this;

    net_Close( (intptr_t)p_access->p_sys );
}

/*****************************************************************************
 * Control:
 *****************************************************************************/
static int Control( access_t *p_access, int i_query, va_list args )
{
    bool   *pb_bool;
    int          *pi_int;
    int64_t      *pi_64;

    switch( i_query )
    {
        /* */
        case ACCESS_CAN_SEEK:
        case ACCESS_CAN_FASTSEEK:
        case ACCESS_CAN_PAUSE:
        case ACCESS_CAN_CONTROL_PACE:
            pb_bool = (bool*)va_arg( args, bool* );
            *pb_bool = false;
            break;
        /* */
        case ACCESS_GET_MTU:
            pi_int = (int*)va_arg( args, int * );
            *pi_int = MTU;
            break;

        case ACCESS_GET_PTS_DELAY:
            pi_64 = (int64_t*)va_arg( args, int64_t * );
            *pi_64 = var_GetInteger( p_access, "udp-caching" ) * 1000;
            break;

        /* */
        case ACCESS_SET_PAUSE_STATE:
        case ACCESS_GET_TITLE_INFO:
        case ACCESS_SET_TITLE:
        case ACCESS_SET_SEEKPOINT:
        case ACCESS_SET_PRIVATE_ID_STATE:
        case ACCESS_GET_CONTENT_TYPE:
            return VLC_EGENERIC;

        default:
            msg_Warn( p_access, "unimplemented query in control" );
            return VLC_EGENERIC;

    }
    return VLC_SUCCESS;
}

/*****************************************************************************
 * BlockUDP:
 *****************************************************************************/
static block_t *BlockUDP( access_t *p_access )
{
    access_sys_t *p_sys = p_access->p_sys;
    block_t      *p_block;
    ssize_t len;

    if( p_access->info.b_eof )
        return NULL;

    /* Read data */
    p_block = block_New( p_access, MTU );
    len = net_Read( p_access, (intptr_t)p_sys, NULL,
                    p_block->p_buffer, MTU, false );
    if( len < 0 )
    {
        block_Release( p_block );
        return NULL;
    }

    return block_Realloc( p_block, 0, len );
}
