/*****************************************************************************
 * interface.c: interface access for other threads
 * This library provides basic functions for threads to interact with user
 * interface, such as command line.
 *****************************************************************************
 * Copyright (C) 1998-2001 VideoLAN
 * $Id: interface.c,v 1.97 2002/07/31 20:56:52 sam Exp $
 *
 * Authors: Vincent Seguin <seguin@via.ecp.fr>
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/
#include <errno.h>                                                 /* ENOMEM */
#include <stdlib.h>                                      /* free(), strtol() */
#include <stdio.h>                                                   /* FILE */
#include <string.h>                                            /* strerror() */
#include <sys/types.h>                                              /* off_t */

#include <vlc/vlc.h>

#include "stream_control.h"
#include "input_ext-intf.h"

#include "audio_output.h"

#include "interface.h"

#include "video.h"
#include "video_output.h"

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
static void Manager( intf_thread_t *p_intf );

/*****************************************************************************
 * intf_Create: prepare interface before main loop
 *****************************************************************************
 * This function opens output devices and creates specific interfaces. It sends
 * its own error messages.
 *****************************************************************************/
intf_thread_t* __intf_Create( vlc_object_t *p_this )
{
    intf_thread_t * p_intf;
    char *psz_name;

    /* Allocate structure */
    p_intf = vlc_object_create( p_this, VLC_OBJECT_INTF );
    if( !p_intf )
    {
        msg_Err( p_this, "out of memory" );
        return NULL;
    }

    /* Choose the best module */
    psz_name = config_GetPsz( p_intf, "intf" );
    p_intf->p_module = module_Need( p_intf, "interface", psz_name );

    if( psz_name ) free( psz_name );
    if( p_intf->p_module == NULL )
    {
        msg_Err( p_intf, "no suitable intf module" );
        vlc_object_destroy( p_intf );
        return NULL;
    }

    /* Initialize structure */
    p_intf->b_menu        = 0;
    p_intf->b_menu_change = 0;

    /* Initialize mutexes */
    vlc_mutex_init( p_intf, &p_intf->change_lock );

    msg_Dbg( p_intf, "interface initialized" );

    /* Attach interface to its parent object */
    vlc_object_attach( p_intf, p_this );

    return p_intf;
}

/*****************************************************************************
 * intf_RunThread: launch the interface thread
 *****************************************************************************
 * This function either creates a new thread and runs the interface in it,
 * or runs the interface in the current thread, depending on b_block.
 *****************************************************************************/
vlc_error_t intf_RunThread( intf_thread_t *p_intf )
{
    if( p_intf->b_block )
    {
        /* Run a manager thread, launch the interface, kill the manager */
        if( vlc_thread_create( p_intf, "manager", Manager, 0 ) )
        {
            msg_Err( p_intf, "cannot spawn manager thread" );
            return VLC_EGENERIC;
        }

        p_intf->pf_run( p_intf );

        p_intf->b_die = 1;

        /* Do not join the thread... intf_StopThread will do it for us */
    }
    else
    {
        /* Run the interface in a separate thread */
        if( vlc_thread_create( p_intf, "interface", p_intf->pf_run, 0 ) )
        {
            msg_Err( p_intf, "cannot spawn interface thread" );
            return VLC_EGENERIC;
        }
    }

    return VLC_SUCCESS;
}

/*****************************************************************************
 * intf_StopThread: end the interface thread
 *****************************************************************************
 * This function asks the interface thread to stop.
 *****************************************************************************/
void intf_StopThread( intf_thread_t *p_intf )
{
    /* Tell the interface to die */
    if( !p_intf->b_block )
    {
        p_intf->b_die = 1;
    }

    /* Wait for the thread to exit */
    vlc_thread_join( p_intf );
}

/*****************************************************************************
 * intf_Destroy: clean interface after main loop
 *****************************************************************************
 * This function destroys specific interfaces and close output devices.
 *****************************************************************************/
void intf_Destroy( intf_thread_t *p_intf )
{
    /* Unlock module */
    module_Unneed( p_intf, p_intf->p_module );

    vlc_mutex_destroy( &p_intf->change_lock );

    /* Free structure */
    vlc_object_destroy( p_intf );
}

/* Following functions are local */

/*****************************************************************************
 * Manager: helper thread for blocking interfaces
 *****************************************************************************
 * If the interface is launched in the main thread, it will not listen to
 * p_vlc->b_die events because it is only supposed to listen to p_intf->b_die.
 * This thread takes care of the matter.
 *****************************************************************************/
static void Manager( intf_thread_t *p_intf )
{
    while( !p_intf->b_die )
    {
        msleep( INTF_IDLE_SLEEP );

        if( p_intf->p_vlc->b_die )
        {
            p_intf->b_die = 1;
            return;
        }
    }
}