ImageGrid/ui/lib/keyboard.js
Alex A. Naanou 9cda74ef12 added more generic libs, and some minor changes...
Signed-off-by: Alex A. Naanou <alex.nanou@gmail.com>
2013-04-26 23:07:07 +04:00

327 lines
8.5 KiB
JavaScript
Executable File

/**********************************************************************
*
*
*
**********************************************************************/
//var DEBUG = DEBUG != null ? DEBUG : true
/*********************************************************************/
// Neither _SPECIAL_KEYS nor _KEY_CODES are meant for direct access, use
// toKeyName(<code>) and toKeyCode(<name>) for a more uniform access.
//
// NOTE: these are un-shifted ASCII key names rather than actual key
// code translations.
// NOTE: ASCII letters (capital) are not present because they actually
// match their key codes and are accessible via:
// String.fromCharCode(<code>) or <letter>.charCodeAt(0)
// NOTE: the lower case letters are accessible by adding 32 to the
// capital key code.
// NOTE: don't understand why am I the one who has to write this...
var _SPECIAL_KEYS = {
// Special Keys...
9: 'Tab', 33: 'PgUp', 45: 'Ins',
13: 'Enter', 34: 'PgDown', 46: 'Del',
16: 'Shift', 35: 'End', 80: 'Backspace',
17: 'Ctrl', 36: 'Home', 91: 'Win',
18: 'Alt', 37: 'Left', 93: 'Menu',
20: 'Caps Lock',38: 'Up',
27: 'Esc', 39: 'Right',
32: 'Space', 40: 'Down',
// Function Keys...
112: 'F1', 116: 'F5', 120: 'F9',
113: 'F2', 117: 'F6', 121: 'F10',
114: 'F3', 118: 'F7', 122: 'F11',
115: 'F4', 119: 'F8', 123: 'F12',
// Number row..
49: '1', 50: '2', 51: '3', 52: '4', 53: '5',
54: '6', 55: '7', 56: '8', 57: '9', 48: '0',
// Punctuation...
// top row...
192: '`', /* Numbers */ 189: '-', 187: '=',
// right side of keyboard...
219: '[', 221: ']', 220: '\\',
186: ';', 222: '\'',
188: ',', 190: '.', 191: '/',
}
var _KEY_CODES = {}
for(var k in _SPECIAL_KEYS){
_KEY_CODES[_SPECIAL_KEYS[k]] = k
}
// XXX some keys look really wrong...
function toKeyName(code){
// check for special keys...
var k = _SPECIAL_KEYS[code]
if(k != null){
return k
}
// chars...
k = String.fromCharCode(code)
if(k != ''){
//return k.toLowerCase()
return k
}
return null
}
function toKeyCode(c){
if(c in _KEY_CODES){
return _KEY_CODES[c]
}
return c.charCodeAt(0)
}
// if set to false the event handlers will always return false...
var KEYBOARD_HANDLER_PROPAGATE = true
/* Basic key binding format:
*
* {
* <css-selector>: {
* // meta-data used to generate user docs/help/config
* title: <text>,
* doc: <text>,
*
* // this defines the list of keys to ignore by the handler.
* // NOTE: use "*" to ignore all keys other than explicitly
* // defined in the current section.
* ignore: <ignored-keys>
*
* <key-def> : <callback>,
*
* <key-def> : {
* 'default': <callback>,
* // a modifier can be any single modifier, like shift or a
* // combination of modifers like 'ctrl+shift', given in order
* // of priority.
* // supported modifiers are (in order of priority):
* // - ctrl
* // - alt
* // - shift
* <modifer>: [...],
* ...
* },
*
* <key-def> : [
* // this can be any type of handler except for an alias...
* <handler>,
* <doc>
* ],
*
* // alias...
* <key-def-a> : <key-def-b>,
*
* ...
* },
*
* ...
* }
*
*
* <key-def> can be:
* - explicit key code, e.g. 65
* - key name, if present in _SPECIAL_KEYS, e.g. Enter
* - key char (uppercase), as is returned by String.fromCharCode(...) e.g. A
*
*
* NOTE: to rest what to use as <key-def> use toKeyCode(..) / toKeyName(..).
* NOTE: all fields are optional.
* NOTE: if a handler explicitly returns false then that will break the
* event propagation chain and exit the handler.
* i.e. no other matching handlers will be called.
* NOTE: a <css-selector> is used as a predicate to select a section to
* use. if multiple selectors match something then multiple sections
* will be resolved in order of occurrence.
*
* XXX might need to add meta information to generate sensible help...
*/
function makeKeyboardHandler(keybindings, unhandled){
if(unhandled == null){
//unhandled = function(){return false}
unhandled = function(){return KEYBOARD_HANDLER_PROPAGATE}
}
return function(evt){
var did_handling = false
var res = null
for(var mode in keybindings){
if($(mode).length > 0){
var bindings = keybindings[mode]
var key = evt.keyCode
var chr = toKeyName(evt.keyCode)
// normalize the modifiers...
var modifers = evt.ctrlKey ? 'ctrl' : ''
modifers += evt.altKey ? (modifers != '' ? '+alt' : 'alt') : ''
modifers += evt.shiftKey ? (modifers != '' ? '+shift' : 'shift') : ''
if(chr in bindings){
var handler = bindings[chr]
} else {
var handler = bindings[key]
}
// alias...
while (typeof(handler) == typeof(123) || typeof(handler) == typeof('str')) {
if(handler in bindings){
// XXX need to take care of that we can always be a number or a string...
handler = bindings[handler]
} else if(typeof(h) == typeof(1)) {
handler = bindings[toKeyName(handler)]
} else {
handler = bindings[toKeyCode(handler)]
}
}
// no handler...
if(handler == null){
// if something is ignored then just breakout and stop handling...
if(bindings.ignore == '*'
|| bindings.ignore != null && bindings.ignore.indexOf(key) != -1){
res = res == null ? true : res
did_handling = true
// ignoring a key will stop processing it...
break
}
continue
}
// Array, lisp style with docs...
// XXX for some odd reason typeof([]) == typeof({})!!!
if(typeof(handler) == typeof([]) && handler.constructor.name == 'Array'){
// we do not care about docs here, so just get the handler...
handler = handler[0]
}
// complex handler...
if(typeof(handler) == typeof({})){
var callback = handler[modifers]
if(callback == null){
callback = handler['default']
}
if(callback != null){
res = callback()
did_handling = true
continue
}
} else {
// simple callback...
//res = handler(evt)
res = handler()
// if the handler explicitly returned false break out...
if(res === false){
// XXX is this corrent???
// XXX should we just break here instead of return...
return KEYBOARD_HANDLER_PROPAGATE ? res : null
}
did_handling = true
continue
}
}
}
if(!did_handling){
// key is unhandled by any modes...
return unhandled(key)
} else {
// XXX should we handle multiple hits???
return KEYBOARD_HANDLER_PROPAGATE&&res?true:false
}
}
}
// helper...
function doc(text, func){
func.doc = text
return func
}
/* Build structure ready for conversion to HTML help.
* Structure:
* {
* <section-title>: {
* doc: ...
*
* <handler-doc>: <keys-spec>
* ...
* }
* }
*
* <keys-spec> - list of key names.
*
*/
function getKeyHandler(key, keybindings){
}
function buildKeyindingsHelp(keybindings){
var res = {}
for(var selector in keybindings){
var section = keybindings[selector]
var title = section.title == null ? selector : section.title
var res_sec = {
doc: section.doc,
}
res.title = res_sec
for(var k in section){
// handler...
var h = section[k]
var doc
var key = typeof(k) == typeof(1) ? toKeyName(k) : k
// an alias...
while(typeof(h) == typeof(1) || typeof(h) == typeof('s')){
if(h in section){
// XXX need to take care of that we can always be a number or a string...
h = section[h]
} else if(typeof(h) == typeof(1)) {
h = section[toKeyName(h)]
} else {
h = section[toKeyCode(h)]
}
}
// no handler...
if(h == null){
doc = 'Nothing'
// a handler with doc (array)...
} else if(typeof(h) == typeof([]) && handler.constructor.name == 'Array'){
doc = h[1]
// complex handler (object)...
} else if(typeof(h) == typeof({})){
// XXX
// simple handler (function)...
} else {
doc = h.doc != null ? h.doc : h
}
// push the actual data...
if(doc in res_sec){
res_sec[doc].push(key)
} else {
res_sec[doc] = [key]
}
}
}
return res
}
/**********************************************************************
* vim:set ts=4 sw=4 : */