source: trunk/admin/inc/FCKeditor/editor/_source/internals/fckundo_ie.js@ 2

/*
 * FCKeditor - The text editor for internet
 * Copyright (C) 2003-2006 Frederico Caldeira Knabben
 * 
 * Licensed under the terms of the GNU Lesser General Public License:
 *              http://www.opensource.org/licenses/lgpl-license.php
 * 
 * For further information visit:
 *              http://www.fckeditor.net/
 * 
 * "Support Open Source software. What about a donation today?"
 * 
 * File Name: fckundo_ie.js
 *      IE specific implementation for the Undo/Redo system.
 * 
 * File Authors:
 *              Frederico Caldeira Knabben (fredck@fckeditor.net)
 */

var FCKUndo = new Object() ;

FCKUndo.SavedData = new Array() ;
FCKUndo.CurrentIndex = -1 ;
FCKUndo.TypesCount = FCKUndo.MaxTypes = 25 ;
FCKUndo.Typing = false ;

FCKUndo.SaveUndoStep = function()
{
        if ( FCK.EditMode != FCK_EDITMODE_WYSIWYG )
                return ;

        // Shrink the array to the current level.
        FCKUndo.SavedData = FCKUndo.SavedData.slice( 0, FCKUndo.CurrentIndex + 1 ) ;

        // Get the Actual HTML.
        var sHtml = FCK.EditorDocument.body.innerHTML ;

        // Cancel operation if the new step is identical to the previous one.
        if ( FCKUndo.CurrentIndex >= 0 && sHtml == FCKUndo.SavedData[ FCKUndo.CurrentIndex ][0] )
                return ;

        // If we reach the Maximun number of undo levels, we must remove the first
        // entry of the list shifting all elements.
        if ( FCKUndo.CurrentIndex + 1 >= FCKConfig.MaxUndoLevels )
                FCKUndo.SavedData.shift() ;
        else
                FCKUndo.CurrentIndex++ ;

        // Get the actual selection.
        var sBookmark ;
        if ( FCK.EditorDocument.selection.type == 'Text' )
                sBookmark = FCK.EditorDocument.selection.createRange().getBookmark() ;

        // Save the new level in front of the actual position.
        FCKUndo.SavedData[ FCKUndo.CurrentIndex ] = [ sHtml, sBookmark ] ;

        FCK.Events.FireEvent( "OnSelectionChange" ) ;
}

FCKUndo.CheckUndoState = function()
{
        return ( FCKUndo.Typing || FCKUndo.CurrentIndex > 0 ) ;
}

FCKUndo.CheckRedoState = function()
{
        return ( !FCKUndo.Typing && FCKUndo.CurrentIndex < ( FCKUndo.SavedData.length - 1 ) ) ;
}

FCKUndo.Undo = function()
{
        if ( FCKUndo.CheckUndoState() )
        {
                // If it is the first step.
                if ( FCKUndo.CurrentIndex == ( FCKUndo.SavedData.length - 1 ) )
                {
                        // Save the actual state for a possible "Redo" call.
                        FCKUndo.SaveUndoStep() ;
                }

                // Go a step back.
                FCKUndo._ApplyUndoLevel( --FCKUndo.CurrentIndex ) ;

                FCK.Events.FireEvent( "OnSelectionChange" ) ;
        }
}

FCKUndo.Redo = function()
{
        if ( FCKUndo.CheckRedoState() )
        {
                // Go a step forward.
                FCKUndo._ApplyUndoLevel( ++FCKUndo.CurrentIndex ) ;

                FCK.Events.FireEvent( "OnSelectionChange" ) ;
        }
}

FCKUndo._ApplyUndoLevel = function(level)
{
        var oData = FCKUndo.SavedData[ level ] ;
        
        if ( !oData )
                return ;

        // Update the editor contents with that step data.
        FCK.SetInnerHtml( oData[0] ) ;
//      FCK.EditorDocument.body.innerHTML = oData[0] ;

        if ( oData[1] ) 
        {
                var oRange = FCK.EditorDocument.selection.createRange() ;
                oRange.moveToBookmark( oData[1] ) ;
                oRange.select() ;
        }
        
        FCKUndo.TypesCount = 0 ; 
        FCKUndo.Typing = false ;
}