/* -*- Mode: IDL; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"

/**
 * An optional interface for embedding clients wishing to receive
 * notifications for when a tooltip should be displayed or removed.
 * The embedder implements this interface on the web browser chrome
 * object associated with the window that notifications are required
 * for.
 *
 * @see nsITooltipTextProvider
 */
[scriptable, uuid(44b78386-1dd2-11b2-9ad2-e4eee2ca1916)]
interface nsITooltipListener : nsISupports
{
    /**
     * Called when a tooltip should be displayed.
     *
     * @param aXCoords The tooltip left edge X coordinate.
     * @param aYCoords The tooltip top edge Y coordinate.
     * @param aTipText The text to display in the tooltip, typically obtained
     *        from the TITLE attribute of the node (or containing parent)
     *        over which the pointer has been positioned.
     * @param aTipDir  The direction (ltr or rtl) in which to display the text
     *
     * @note
     * Coordinates are specified in device pixels, relative to the top-left
     * corner of the browser area.
     *
     * @return <code>NS_OK</code> if the tooltip was displayed.
     */
    void onShowTooltip(in long aXCoords, in long aYCoords, in AString aTipText,
                       in AString aTipDir);

    /**
     * Called when the tooltip should be hidden, either because the pointer
     * has moved or the tooltip has timed out.
     */
    void onHideTooltip();
};