/* create_filesink_tail function to create a new multisink element
 * end link it to the pipeline
 * */
static void create_filesink_tail()
{
    GstPad *srcpad;
    GstPad *sinkpad;
    
   //Create the new multisink element
   multisink = NULL;
   multisink = gst_element_factory_make ("filesink", NULL);

    if(!multisink)
    {
        g_print("failed to create new sink element! \n");
        return;
    }

    //add it to the bin
    gst_bin_add(GST_BIN (pipeline), multisink);
    
        //switch the filename
    sprintf(name_buf, "image%05d.jpg", counter++);
    g_print ("File Switching %s\n", name_buf);
    g_object_set( G_OBJECT( multisink ), "location", name_buf, NULL );
    
    //get and link the pads
    gst_element_link(multi_queue, multisink);
    srcpad = gst_element_get_static_pad( multi_queue, "src" );
    sinkpad = gst_element_get_static_pad( multisink, "sink" );
    
    gst_element_link_pads (multi_queue, "src", multisink, "sink");
    
    
    gst_element_set_state (multisink, GST_STATE_PLAYING);
}

/*
 *  destroy_bin_cb function to remove the multisink element from the pipeline
 *  */
static gboolean destroy_bin_cb (gpointer user_data)
{
    //oldbin is multisink element easy way to destroy it by using pipeline remove
    GstElement *oldbin = (GstElement *) user_data;

    g_print("Destroying old bin.\n");
    if (pipeline)
    {
        //move it to the NULL state and remove it from the pipeline
        gst_element_set_state (oldbin, GST_STATE_NULL);
        gst_bin_remove (GST_BIN(pipeline), oldbin);
    }
    return FALSE;
}


/* replace_filesink_blocked_cb  Callback function to block the block, unlink pads
 * */

static void replace_filesink_blocked_cb (GstPad *pad, gboolean blocked, gpointer user_data)
{
    int ret;
    
    if (blocked)
    {
        GstElement *oldbin;
        GstPad *sinkpad;

       
        g_print("Blocked filesink queue.\n");
        g_static_rec_mutex_lock(&mutex);
        g_print("Locked.\n");
        oldbin = multisink;
        sinkpad = gst_element_get_static_pad(multisink, "sink");
        if (!sinkpad)
        {
            g_print("replace_filesink_blocked_cb: oldbin doesn't have sink pad.\n");
            goto fail;
        }
        
        //Unlink pads
        gst_pad_unlink(multi_queue_srcpad, sinkpad);
        g_print("Unlinked.\n");

        //send EOS to the multisink sinkpad
        gst_pad_send_event(sinkpad, gst_event_new_eos());
        g_print("Sent event.\n");

        g_print("Checked sinks.\n");
        
   
    
        g_print("Destroying old bin.\n");
        if (pipeline)
        {
        //move it to the NULL state and remove it from the pipeline
        gst_element_set_state (oldbin, GST_STATE_NULL);
        gst_bin_remove (GST_BIN(pipeline), oldbin);
        }
             
    
       
       
        //call the tail to create the new multisink element
        create_filesink_tail();
        
        
        
        g_print("Created filesink.\n");
        g_static_rec_mutex_unlock(&mutex);
        g_print("Unlocked mutex.\n");

        /* And unblock again. */
        ret = gst_pad_set_blocked_async(multi_queue_srcpad, gboolean (FALSE), replace_filesink_blocked_cb, NULL);
        g_print("gst_pad_set_unblocked_async ret : %d \n", ret );

        g_print("Done replacing filesink.\n");
    }
    else
    {
        g_print("Unblocked filesink queue.\n");
    }
    return;

fail:
    g_print("FAIL!!!\n");
}

/*replace_filesink function to replace the multisink element
 * */
static void replace_filesink()
{
    int ret;
    
    if (multi_queue_srcpad == NULL)
        g_print("replace_filesink while no multi_queue_srcpad yet, waiting for it to appear.\n");
    else
    {
       ret =  gst_pad_set_blocked_async(multi_queue_srcpad, TRUE, replace_filesink_blocked_cb, NULL);
       g_print("gst_pad_set_blocked_async ret : %d \n", ret );
    }
}