1/*
2 * FCKeditor - The text editor for Internet - http://www.fckeditor.net
3 * Copyright (C) 2003-2007 Frederico Caldeira Knabben
4 *
5 * == BEGIN LICENSE ==
6 *
7 * Licensed under the terms of any of the following licenses at your
8 * choice:
9 *
10 *  - GNU General Public License Version 2 or later (the "GPL")
11 *    http://www.gnu.org/licenses/gpl.html
12 *
13 *  - GNU Lesser General Public License Version 2.1 or later (the "LGPL")
14 *    http://www.gnu.org/licenses/lgpl.html
15 *
16 *  - Mozilla Public License Version 1.1 or later (the "MPL")
17 *    http://www.mozilla.org/MPL/MPL-1.1.html
18 *
19 * == END LICENSE ==
20 *
21 * Control keyboard keystroke combinations.
22 */
23
24var FCKKeystrokeHandler = function( cancelCtrlDefaults )
25{
26	this.Keystrokes = new Object() ;
27	this.CancelCtrlDefaults = ( cancelCtrlDefaults !== false ) ;
28}
29
30/*
31 * Listen to keystroke events in an element or DOM document object.
32 *		@target: The element or document to listen to keystroke events.
33 */
34FCKKeystrokeHandler.prototype.AttachToElement = function( target )
35{
36	// For newer browsers, it is enough to listen to the keydown event only.
37	// Some browsers instead, don't cancel key events in the keydown, but in the
38	// keypress. So we must do a longer trip in those cases.
39	FCKTools.AddEventListenerEx( target, 'keydown', _FCKKeystrokeHandler_OnKeyDown, this ) ;
40	if ( FCKBrowserInfo.IsGecko10 || FCKBrowserInfo.IsOpera || ( FCKBrowserInfo.IsGecko && FCKBrowserInfo.IsMac ) )
41		FCKTools.AddEventListenerEx( target, 'keypress', _FCKKeystrokeHandler_OnKeyPress, this ) ;
42}
43
44/*
45 * Sets a list of keystrokes. It can receive either a single array or "n"
46 * arguments, each one being an array of 1 or 2 elemenst. The first element
47 * is the keystroke combination, and the second is the value to assign to it.
48 * If the second element is missing, the keystroke definition is removed.
49 */
50FCKKeystrokeHandler.prototype.SetKeystrokes = function()
51{
52	// Look through the arguments.
53	for ( var i = 0 ; i < arguments.length ; i++ )
54	{
55		var keyDef = arguments[i] ;
56
57		// If the configuration for the keystrokes is missing some element or has any extra comma
58		// this item won't be valid, so skip it and keep on processing.
59		if ( !keyDef )
60			continue ;
61
62		if ( typeof( keyDef[0] ) == 'object' )		// It is an array with arrays defining the keystrokes.
63			this.SetKeystrokes.apply( this, keyDef ) ;
64		else
65		{
66			if ( keyDef.length == 1 )		// If it has only one element, remove the keystroke.
67				delete this.Keystrokes[ keyDef[0] ] ;
68			else							// Otherwise add it.
69				this.Keystrokes[ keyDef[0] ] = keyDef[1] === true ? true : keyDef ;
70		}
71	}
72}
73
74function _FCKKeystrokeHandler_OnKeyDown( ev, keystrokeHandler )
75{
76	// Get the key code.
77	var keystroke = ev.keyCode || ev.which ;
78
79	// Combine it with the CTRL, SHIFT and ALT states.
80	var keyModifiers = 0 ;
81
82	if ( ev.ctrlKey || ev.metaKey )
83		keyModifiers += CTRL ;
84
85	if ( ev.shiftKey )
86		keyModifiers += SHIFT ;
87
88	if ( ev.altKey )
89		keyModifiers += ALT ;
90
91	var keyCombination = keystroke + keyModifiers ;
92
93	var cancelIt = keystrokeHandler._CancelIt = false ;
94
95	// Look for its definition availability.
96	var keystrokeValue = keystrokeHandler.Keystrokes[ keyCombination ] ;
97
98//	FCKDebug.Output( 'KeyDown: ' + keyCombination + ' - Value: ' + keystrokeValue ) ;
99
100	// If the keystroke is defined
101	if ( keystrokeValue )
102	{
103		// If the keystroke has been explicitly set to "true" OR calling the
104		// "OnKeystroke" event, it doesn't return "true", the default behavior
105		// must be preserved.
106		if ( keystrokeValue === true || !( keystrokeHandler.OnKeystroke && keystrokeHandler.OnKeystroke.apply( keystrokeHandler, keystrokeValue ) ) )
107			return true ;
108
109		cancelIt = true ;
110	}
111
112	// By default, it will cancel all combinations with the CTRL key only (except positioning keys).
113	if ( cancelIt || ( keystrokeHandler.CancelCtrlDefaults && keyModifiers == CTRL && ( keystroke < 33 || keystroke > 40 ) ) )
114	{
115		keystrokeHandler._CancelIt = true ;
116
117		if ( ev.preventDefault )
118			return ev.preventDefault() ;
119
120		ev.returnValue = false ;
121		ev.cancelBubble = true ;
122		return false ;
123	}
124
125	return true ;
126}
127
128function _FCKKeystrokeHandler_OnKeyPress( ev, keystrokeHandler )
129{
130	if ( keystrokeHandler._CancelIt )
131	{
132//		FCKDebug.Output( 'KeyPress Cancel', 'Red') ;
133
134		if ( ev.preventDefault )
135			return ev.preventDefault() ;
136
137		return false ;
138	}
139
140	return true ;
141}
142