source: extensions/FCKEditor/editor/_source/classes/fckkeystrokehandler.js @ 3295

/*
 * FCKeditor - The text editor for Internet - http://www.fckeditor.net
 * Copyright (C) 2003-2009 Frederico Caldeira Knabben
 *
 * == BEGIN LICENSE ==
 *
 * Licensed under the terms of any of the following licenses at your
 * choice:
 *
 *  - GNU General Public License Version 2 or later (the "GPL")
 *    http://www.gnu.org/licenses/gpl.html
 *
 *  - GNU Lesser General Public License Version 2.1 or later (the "LGPL")
 *    http://www.gnu.org/licenses/lgpl.html
 *
 *  - Mozilla Public License Version 1.1 or later (the "MPL")
 *    http://www.mozilla.org/MPL/MPL-1.1.html
 *
 * == END LICENSE ==
 *
 * Control keyboard keystroke combinations.
 */

var FCKKeystrokeHandler = function( cancelCtrlDefaults )
{
        this.Keystrokes = new Object() ;
        this.CancelCtrlDefaults = ( cancelCtrlDefaults !== false ) ;
}

/*
 * Listen to keystroke events in an element or DOM document object.
 *              @target: The element or document to listen to keystroke events.
 */
FCKKeystrokeHandler.prototype.AttachToElement = function( target )
{
        // For newer browsers, it is enough to listen to the keydown event only.
        // Some browsers instead, don't cancel key events in the keydown, but in the
        // keypress. So we must do a longer trip in those cases.
        FCKTools.AddEventListenerEx( target, 'keydown', _FCKKeystrokeHandler_OnKeyDown, this ) ;
        if ( FCKBrowserInfo.IsGecko10 || FCKBrowserInfo.IsOpera || ( FCKBrowserInfo.IsGecko && FCKBrowserInfo.IsMac ) )
                FCKTools.AddEventListenerEx( target, 'keypress', _FCKKeystrokeHandler_OnKeyPress, this ) ;
}

/*
 * Sets a list of keystrokes. It can receive either a single array or "n"
 * arguments, each one being an array of 1 or 2 elemenst. The first element
 * is the keystroke combination, and the second is the value to assign to it.
 * If the second element is missing, the keystroke definition is removed.
 */
FCKKeystrokeHandler.prototype.SetKeystrokes = function()
{
        // Look through the arguments.
        for ( var i = 0 ; i < arguments.length ; i++ )
        {
                var keyDef = arguments[i] ;

                // If the configuration for the keystrokes is missing some element or has any extra comma
                // this item won't be valid, so skip it and keep on processing.
                if ( !keyDef )
                        continue ;

                if ( typeof( keyDef[0] ) == 'object' )          // It is an array with arrays defining the keystrokes.
                        this.SetKeystrokes.apply( this, keyDef ) ;
                else
                {
                        if ( keyDef.length == 1 )               // If it has only one element, remove the keystroke.
                                delete this.Keystrokes[ keyDef[0] ] ;
                        else                                                    // Otherwise add it.
                                this.Keystrokes[ keyDef[0] ] = keyDef[1] === true ? true : keyDef ;
                }
        }
}

function _FCKKeystrokeHandler_OnKeyDown( ev, keystrokeHandler )
{
        // Get the key code.
        var keystroke = ev.keyCode || ev.which ;

        // Combine it with the CTRL, SHIFT and ALT states.
        var keyModifiers = 0 ;

        if ( ev.ctrlKey || ev.metaKey )
                keyModifiers += CTRL ;

        if ( ev.shiftKey )
                keyModifiers += SHIFT ;

        if ( ev.altKey )
                keyModifiers += ALT ;

        var keyCombination = keystroke + keyModifiers ;

        var cancelIt = keystrokeHandler._CancelIt = false ;

        // Look for its definition availability.
        var keystrokeValue = keystrokeHandler.Keystrokes[ keyCombination ] ;

//      FCKDebug.Output( 'KeyDown: ' + keyCombination + ' - Value: ' + keystrokeValue ) ;

        // If the keystroke is defined
        if ( keystrokeValue )
        {
                // If the keystroke has been explicitly set to "true" OR calling the
                // "OnKeystroke" event, it doesn't return "true", the default behavior
                // must be preserved.
                if ( keystrokeValue === true || !( keystrokeHandler.OnKeystroke && keystrokeHandler.OnKeystroke.apply( keystrokeHandler, keystrokeValue ) ) )
                        return true ;

                cancelIt = true ;
        }

        // By default, it will cancel all combinations with the CTRL key only (except positioning keys).
        if ( cancelIt || ( keystrokeHandler.CancelCtrlDefaults && keyModifiers == CTRL && ( keystroke < 33 || keystroke > 40 ) ) )
        {
                keystrokeHandler._CancelIt = true ;

                if ( ev.preventDefault )
                        return ev.preventDefault() ;

                ev.returnValue = false ;
                ev.cancelBubble = true ;
                return false ;
        }

        return true ;
}

function _FCKKeystrokeHandler_OnKeyPress( ev, keystrokeHandler )
{
        if ( keystrokeHandler._CancelIt )
        {
//              FCKDebug.Output( 'KeyPress Cancel', 'Red') ;

                if ( ev.preventDefault )
                        return ev.preventDefault() ;

                return false ;
        }

        return true ;
}