source: trunk/third/gtkhtml/src/htmlengine-edit-selection-updater.c @ 16767

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*  This file is part of the GtkHTML library.

    Copyright (C) 2000 Helix Code, 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; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
    Boston, MA 02111-1307, USA.
*/

/* WARNING / FIXME : All of this code assumes that the only kind of
   selectable object that does not accept the cursor is
   `HTMLClueFlow'.  */


#include <config.h>
#include <gtk/gtkmain.h>
#include "htmlengine-edit-selection-updater.h"
#include "htmlinterval.h"
#include "htmlselection.h"

struct _HTMLEngineEditSelectionUpdater {
        HTMLEngine *engine;
        gint idle_id;
};


/**
 * html_engine_edit_selection_updater_new:
 * @engine: A GtkHTML engine object.
 * 
 * Create a new updater associated with @engine.
 * 
 * Return value: A pointer to the new updater object.
 **/
HTMLEngineEditSelectionUpdater *
html_engine_edit_selection_updater_new (HTMLEngine *engine)
{
        HTMLEngineEditSelectionUpdater *new;

        g_return_val_if_fail (engine != NULL, NULL);
        g_return_val_if_fail (HTML_IS_ENGINE (engine), NULL);

        new = g_new (HTMLEngineEditSelectionUpdater, 1);

        new->engine  = engine;
        new->idle_id = 0;

        return new;
}

/**
 * html_engine_edit_selection_updater_destroy:
 * @updater: An HTMLEngineEditSelectionUpdater object.
 * 
 * Destroy @updater.
 **/
void
html_engine_edit_selection_updater_destroy (HTMLEngineEditSelectionUpdater *updater)
{
        g_return_if_fail (updater != NULL);

        if (updater->idle_id != 0)
                gtk_idle_remove (updater->idle_id);

        g_free (updater);
}


static gint
updater_idle_callback (gpointer data)
{
        HTMLEngineEditSelectionUpdater *updater;
        HTMLEngine *engine;

        updater = (HTMLEngineEditSelectionUpdater *) data;
        engine = updater->engine;

        if (engine->mark && html_cursor_get_position (engine->mark) != html_cursor_get_position (engine->cursor))
                html_engine_select_interval (engine, html_interval_new_from_cursor (engine->mark, engine->cursor));
        else {
                gboolean selection_mode = engine->selection_mode;

                html_engine_disable_selection (engine);
                engine->selection_mode = selection_mode;
        }

        updater->idle_id = 0;
        return FALSE;
}

/**
 * html_engine_edit_selection_updater_schedule:
 * @updater: An HTMLEngineEditSelectionUpdater object.
 * 
 * Schedule an update for the keyboard-selected region on @updater.
 **/
void
html_engine_edit_selection_updater_schedule (HTMLEngineEditSelectionUpdater *updater)
{
        g_return_if_fail (updater != NULL);

        if (updater->idle_id != 0)
                return;

        updater->idle_id = gtk_idle_add (updater_idle_callback, updater);
}

/**
 * html_engine_edit_selection_updater_reset:
 * @updater: An HTMLEngineEditSelectionUpdater object.
 * 
 * Reset @updater so after no selection is active anymore.
 **/
void
html_engine_edit_selection_updater_reset (HTMLEngineEditSelectionUpdater *updater)
{
        g_return_if_fail (updater != NULL);

        if (updater->idle_id != 0) {
                gtk_idle_remove (updater->idle_id);
                updater->idle_id = 0;
        }
}

/**
 * html_engine_edit_selection_updater_update_now:
 * @updater: An HTMLEngineEditSelectionUpdater object.
 * 
 * Remove @updater idle callback and run's update callback immediately.
 **/
void
html_engine_edit_selection_updater_update_now (HTMLEngineEditSelectionUpdater *updater)
{
        /* remove scheduled idle cb */
        if (updater->idle_id != 0) {
                gtk_idle_remove (updater->idle_id);
                updater->idle_id = 0;
        }

        /* run it now */
        updater_idle_callback (updater);
}

void
html_engine_edit_selection_updater_do_idle (HTMLEngineEditSelectionUpdater *updater)
{
        /* remove scheduled idle cb */
        if (updater->idle_id != 0) {
                gtk_idle_remove (updater->idle_id);
                updater->idle_id = 0;

                /* run it now */
                updater_idle_callback (updater);
        }
}