/* -*- Mode: C; tab-width: 8; indent-tabs-mode: 8; c-basic-offset: 8 -*- */

/*
 *  libcaja: A library for caja view implementations.
 *
 *  Copyright (C) 2001 Eazel, Inc.
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Library General Public
 *  License as published by the Free Software Foundation; either
 *  version 2 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Library General Public License for more details.
 *
 *  You should have received a copy of the GNU Library General Public
 *  License along with this library; if not, write to the Free
 *  Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *  Author: Darin Adler <darin@bentspoon.com>
 *
 */

#include <config.h>
#include "caja-idle-queue.h"

#include <gtk/gtk.h>

struct CajaIdleQueue
{
    GList *functions;
    guint idle_id;
    gboolean in_idle;
    gboolean destroy;
};

typedef struct
{
    GFunc callback;
    gpointer data;
    gpointer callback_data;
    GFreeFunc free_callback_data;
} QueuedFunction;

static gboolean
execute_queued_functions (gpointer callback_data)
{
    CajaIdleQueue *queue;
    GList *functions, *node;
    QueuedFunction *function;

    queue = callback_data;

    /* We could receive more incoming functions while dispatching
     * these, so keep going until the queue is empty.
     */
    queue->in_idle = TRUE;
    while (queue->functions != NULL)
    {
        functions = g_list_reverse (queue->functions);
        queue->functions = NULL;

        for (node = functions; node != NULL; node = node->next)
        {
            function = node->data;

            if (!queue->destroy)
            {
                (* function->callback) (function->data, function->callback_data);
            }
            if (function->free_callback_data != NULL)
            {
                (* function->free_callback_data) (function->callback_data);
            }

            g_free (function);
        }

        g_list_free (functions);
    }
    queue->in_idle = FALSE;

    queue->idle_id = 0;

    if (queue->destroy)
    {
        caja_idle_queue_destroy (queue);
    }

    return FALSE;
}

CajaIdleQueue *
caja_idle_queue_new (void)
{
    return g_new0 (CajaIdleQueue, 1);
}

void
caja_idle_queue_add (CajaIdleQueue *queue,
                     GFunc callback,
                     gpointer data,
                     gpointer callback_data,
                     GFreeFunc free_callback_data)
{
    QueuedFunction *function;

    function = g_new (QueuedFunction, 1);
    function->callback = callback;
    function->data = data;
    function->callback_data = callback_data;
    function->free_callback_data = free_callback_data;

    queue->functions = g_list_prepend (queue->functions, function);

    if (queue->idle_id == 0)
    {
        queue->idle_id = g_idle_add (execute_queued_functions, queue);
    }
}

void
caja_idle_queue_destroy (CajaIdleQueue *queue)
{
    GList *node;
    QueuedFunction *function;

    if (queue->in_idle)
    {
        queue->destroy = TRUE;
        return;
    }

    for (node = queue->functions; node != NULL; node = node->next)
    {
        function = node->data;

        if (function->free_callback_data != NULL)
        {
            (* function->free_callback_data) (function->callback_data);
        }

        g_free (function);
    }

    g_list_free (queue->functions);

    if (queue->idle_id != 0)
    {
        g_source_remove (queue->idle_id);
    }

    g_free (queue);
}
