Javascript
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544行
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20.28 KB
var kbdUtil = (function() {
"use strict";
function substituteCodepoint(cp) {
// Any Unicode code points which do not have corresponding keysym entries
// can be swapped out for another code point by adding them to this table
var substitutions = {
// {S,s} with comma below -> {S,s} with cedilla
0x218 : 0x15e,
0x219 : 0x15f,
// {T,t} with comma below -> {T,t} with cedilla
0x21a : 0x162,
0x21b : 0x163
};
var sub = substitutions[cp];
return sub ? sub : cp;
}
function isMac() {
return navigator && !!(/mac/i).exec(navigator.platform);
}
function isWindows() {
return navigator && !!(/win/i).exec(navigator.platform);
}
function isLinux() {
return navigator && !!(/linux/i).exec(navigator.platform);
}
// Return true if a modifier which is not the specified char modifier (and is not shift) is down
function hasShortcutModifier(charModifier, currentModifiers) {
var mods = {};
for (var key in currentModifiers) {
if (parseInt(key) !== 0xffe1) {
mods[key] = currentModifiers[key];
}
}
var sum = 0;
for (var k in currentModifiers) {
if (mods[k]) {
++sum;
}
}
if (hasCharModifier(charModifier, mods)) {
return sum > charModifier.length;
}
else {
return sum > 0;
}
}
// Return true if the specified char modifier is currently down
function hasCharModifier(charModifier, currentModifiers) {
if (charModifier.length === 0) { return false; }
for (var i = 0; i < charModifier.length; ++i) {
if (!currentModifiers[charModifier[i]]) {
return false;
}
}
return true;
}
// Helper object tracking modifier key state
// and generates fake key events to compensate if it gets out of sync
function ModifierSync(charModifier) {
var ctrl = 0xffe3;
var alt = 0xffe9;
var altGr = 0xfe03;
var shift = 0xffe1;
var meta = 0xffe7;
if (!charModifier) {
if (isMac()) {
// on Mac, Option (AKA Alt) is used as a char modifier
charModifier = [alt];
}
else if (isWindows()) {
// on Windows, Ctrl+Alt is used as a char modifier
charModifier = [alt, ctrl];
}
else if (isLinux()) {
// on Linux, AltGr is used as a char modifier
charModifier = [altGr];
}
else {
charModifier = [];
}
}
var state = {};
state[ctrl] = false;
state[alt] = false;
state[altGr] = false;
state[shift] = false;
state[meta] = false;
function sync(evt, keysym) {
var result = [];
function syncKey(keysym) {
return {keysym: keysyms.lookup(keysym), type: state[keysym] ? 'keydown' : 'keyup'};
}
if (evt.ctrlKey !== undefined && evt.ctrlKey !== state[ctrl] && keysym !== ctrl) {
state[ctrl] = evt.ctrlKey;
result.push(syncKey(ctrl));
}
if (evt.altKey !== undefined && evt.altKey !== state[alt] && keysym !== alt) {
state[alt] = evt.altKey;
result.push(syncKey(alt));
}
if (evt.altGraphKey !== undefined && evt.altGraphKey !== state[altGr] && keysym !== altGr) {
state[altGr] = evt.altGraphKey;
result.push(syncKey(altGr));
}
if (evt.shiftKey !== undefined && evt.shiftKey !== state[shift] && keysym !== shift) {
state[shift] = evt.shiftKey;
result.push(syncKey(shift));
}
if (evt.metaKey !== undefined && evt.metaKey !== state[meta] && keysym !== meta) {
state[meta] = evt.metaKey;
result.push(syncKey(meta));
}
return result;
}
function syncKeyEvent(evt, down) {
var obj = getKeysym(evt);
var keysym = obj ? obj.keysym : null;
// first, apply the event itself, if relevant
if (keysym !== null && state[keysym] !== undefined) {
state[keysym] = down;
}
return sync(evt, keysym);
}
return {
// sync on the appropriate keyboard event
keydown: function(evt) { return syncKeyEvent(evt, true);},
keyup: function(evt) { return syncKeyEvent(evt, false);},
// Call this with a non-keyboard event (such as mouse events) to use its modifier state to synchronize anyway
syncAny: function(evt) { return sync(evt);},
// is a shortcut modifier down?
hasShortcutModifier: function() { return hasShortcutModifier(charModifier, state); },
// if a char modifier is down, return the keys it consists of, otherwise return null
activeCharModifier: function() { return hasCharModifier(charModifier, state) ? charModifier : null; }
};
}
// Get a key ID from a keyboard event
// May be a string or an integer depending on the available properties
function getKey(evt){
if ('keyCode' in evt && 'key' in evt) {
return evt.key + ':' + evt.keyCode;
}
else if ('keyCode' in evt) {
return evt.keyCode;
}
else {
return evt.key;
}
}
// Get the most reliable keysym value we can get from a key event
// if char/charCode is available, prefer those, otherwise fall back to key/keyCode/which
function getKeysym(evt){
var codepoint;
if (evt.char && evt.char.length === 1) {
codepoint = evt.char.charCodeAt();
}
else if (evt.charCode) {
codepoint = evt.charCode;
}
else if (evt.keyCode && evt.type === 'keypress') {
// IE10 stores the char code as keyCode, and has no other useful properties
codepoint = evt.keyCode;
}
if (codepoint) {
var res = keysyms.fromUnicode(substituteCodepoint(codepoint));
if (res) {
return res;
}
}
// we could check evt.key here.
// Legal values are defined in http://www.w3.org/TR/DOM-Level-3-Events/#key-values-list,
// so we "just" need to map them to keysym, but AFAIK this is only available in IE10, which also provides evt.key
// so we don't *need* it yet
if (evt.keyCode) {
return keysyms.lookup(keysymFromKeyCode(evt.keyCode, evt.shiftKey));
}
if (evt.which) {
return keysyms.lookup(keysymFromKeyCode(evt.which, evt.shiftKey));
}
return null;
}
// Given a keycode, try to predict which keysym it might be.
// If the keycode is unknown, null is returned.
function keysymFromKeyCode(keycode, shiftPressed) {
if (typeof(keycode) !== 'number') {
return null;
}
// won't be accurate for azerty
if (keycode >= 0x30 && keycode <= 0x39) {
return keycode; // digit
}
if (keycode >= 0x41 && keycode <= 0x5a) {
// remap to lowercase unless shift is down
return shiftPressed ? keycode : keycode + 32; // A-Z
}
if (keycode >= 0x60 && keycode <= 0x69) {
return 0xffb0 + (keycode - 0x60); // numpad 0-9
}
switch(keycode) {
case 0x20: return 0x20; // space
case 0x6a: return 0xffaa; // multiply
case 0x6b: return 0xffab; // add
case 0x6c: return 0xffac; // separator
case 0x6d: return 0xffad; // subtract
case 0x6e: return 0xffae; // decimal
case 0x6f: return 0xffaf; // divide
case 0xbb: return 0x2b; // +
case 0xbc: return 0x2c; // ,
case 0xbd: return 0x2d; // -
case 0xbe: return 0x2e; // .
}
return nonCharacterKey({keyCode: keycode});
}
// if the key is a known non-character key (any key which doesn't generate character data)
// return its keysym value. Otherwise return null
function nonCharacterKey(evt) {
// evt.key not implemented yet
if (!evt.keyCode) { return null; }
var keycode = evt.keyCode;
if (keycode >= 0x70 && keycode <= 0x87) {
return 0xffbe + keycode - 0x70; // F1-F24
}
switch (keycode) {
case 8 : return 0xFF08; // BACKSPACE
case 13 : return 0xFF0D; // ENTER
case 9 : return 0xFF09; // TAB
case 27 : return 0xFF1B; // ESCAPE
case 46 : return 0xFFFF; // DELETE
case 36 : return 0xFF50; // HOME
case 35 : return 0xFF57; // END
case 33 : return 0xFF55; // PAGE_UP
case 34 : return 0xFF56; // PAGE_DOWN
case 45 : return 0xFF63; // INSERT
case 37 : return 0xFF51; // LEFT
case 38 : return 0xFF52; // UP
case 39 : return 0xFF53; // RIGHT
case 40 : return 0xFF54; // DOWN
case 16 : return 0xFFE1; // SHIFT
case 17 : return 0xFFE3; // CONTROL
case 18 : return 0xFFE9; // Left ALT (Mac Option)
case 224 : return 0xFE07; // Meta
case 225 : return 0xFE03; // AltGr
case 91 : return 0xFFEC; // Super_L (Win Key)
case 92 : return 0xFFED; // Super_R (Win Key)
case 93 : return 0xFF67; // Menu (Win Menu), Mac Command
default: return null;
}
}
return {
hasShortcutModifier : hasShortcutModifier,
hasCharModifier : hasCharModifier,
ModifierSync : ModifierSync,
getKey : getKey,
getKeysym : getKeysym,
keysymFromKeyCode : keysymFromKeyCode,
nonCharacterKey : nonCharacterKey,
substituteCodepoint : substituteCodepoint
};
})();
// Takes a DOM keyboard event and:
// - determines which keysym it represents
// - determines a keyId identifying the key that was pressed (corresponding to the key/keyCode properties on the DOM event)
// - synthesizes events to synchronize modifier key state between which modifiers are actually down, and which we thought were down
// - marks each event with an 'escape' property if a modifier was down which should be "escaped"
// - generates a "stall" event in cases where it might be necessary to wait and see if a keypress event follows a keydown
// This information is collected into an object which is passed to the next() function. (one call per event)
function KeyEventDecoder(modifierState, next) {
"use strict";
function sendAll(evts) {
for (var i = 0; i < evts.length; ++i) {
next(evts[i]);
}
}
function process(evt, type) {
var result = {type: type};
var keyId = kbdUtil.getKey(evt);
if (keyId) {
result.keyId = keyId;
}
var keysym = kbdUtil.getKeysym(evt);
var hasModifier = modifierState.hasShortcutModifier() || !!modifierState.activeCharModifier();
// Is this a case where we have to decide on the keysym right away, rather than waiting for the keypress?
// "special" keys like enter, tab or backspace don't send keypress events,
// and some browsers don't send keypresses at all if a modifier is down
if (keysym && (type !== 'keydown' || kbdUtil.nonCharacterKey(evt) || hasModifier)) {
result.keysym = keysym;
}
var isShift = evt.keyCode === 0x10 || evt.key === 'Shift';
// Should we prevent the browser from handling the event?
// Doing so on a keydown (in most browsers) prevents keypress from being generated
// so only do that if we have to.
var suppress = !isShift && (type !== 'keydown' || modifierState.hasShortcutModifier() || !!kbdUtil.nonCharacterKey(evt));
// If a char modifier is down on a keydown, we need to insert a stall,
// so VerifyCharModifier knows to wait and see if a keypress is comnig
var stall = type === 'keydown' && modifierState.activeCharModifier() && !kbdUtil.nonCharacterKey(evt);
// if a char modifier is pressed, get the keys it consists of (on Windows, AltGr is equivalent to Ctrl+Alt)
var active = modifierState.activeCharModifier();
// If we have a char modifier down, and we're able to determine a keysym reliably
// then (a) we know to treat the modifier as a char modifier,
// and (b) we'll have to "escape" the modifier to undo the modifier when sending the char.
if (active && keysym) {
var isCharModifier = false;
for (var i = 0; i < active.length; ++i) {
if (active[i] === keysym.keysym) {
isCharModifier = true;
}
}
if (type === 'keypress' && !isCharModifier) {
result.escape = modifierState.activeCharModifier();
}
}
if (stall) {
// insert a fake "stall" event
next({type: 'stall'});
}
next(result);
return suppress;
}
return {
keydown: function(evt) {
sendAll(modifierState.keydown(evt));
return process(evt, 'keydown');
},
keypress: function(evt) {
return process(evt, 'keypress');
},
keyup: function(evt) {
sendAll(modifierState.keyup(evt));
return process(evt, 'keyup');
},
syncModifiers: function(evt) {
sendAll(modifierState.syncAny(evt));
},
releaseAll: function() { next({type: 'releaseall'}); }
};
}
// Combines keydown and keypress events where necessary to handle char modifiers.
// On some OS'es, a char modifier is sometimes used as a shortcut modifier.
// For example, on Windows, AltGr is synonymous with Ctrl-Alt. On a Danish keyboard layout, AltGr-2 yields a @, but Ctrl-Alt-D does nothing
// so when used with the '2' key, Ctrl-Alt counts as a char modifier (and should be escaped), but when used with 'D', it does not.
// The only way we can distinguish these cases is to wait and see if a keypress event arrives
// When we receive a "stall" event, wait a few ms before processing the next keydown. If a keypress has also arrived, merge the two
function VerifyCharModifier(next) {
"use strict";
var queue = [];
var timer = null;
function process() {
if (timer) {
return;
}
var delayProcess = function () {
clearTimeout(timer);
timer = null;
process();
};
while (queue.length !== 0) {
var cur = queue[0];
queue = queue.splice(1);
switch (cur.type) {
case 'stall':
// insert a delay before processing available events.
/* jshint loopfunc: true */
timer = setTimeout(delayProcess, 5);
/* jshint loopfunc: false */
return;
case 'keydown':
// is the next element a keypress? Then we should merge the two
if (queue.length !== 0 && queue[0].type === 'keypress') {
// Firefox sends keypress even when no char is generated.
// so, if keypress keysym is the same as we'd have guessed from keydown,
// the modifier didn't have any effect, and should not be escaped
if (queue[0].escape && (!cur.keysym || cur.keysym.keysym !== queue[0].keysym.keysym)) {
cur.escape = queue[0].escape;
}
cur.keysym = queue[0].keysym;
queue = queue.splice(1);
}
break;
}
// swallow stall events, and pass all others to the next stage
if (cur.type !== 'stall') {
next(cur);
}
}
}
return function(evt) {
queue.push(evt);
process();
};
}
// Keeps track of which keys we (and the server) believe are down
// When a keyup is received, match it against this list, to determine the corresponding keysym(s)
// in some cases, a single key may produce multiple keysyms, so the corresponding keyup event must release all of these chars
// key repeat events should be merged into a single entry.
// Because we can't always identify which entry a keydown or keyup event corresponds to, we sometimes have to guess
function TrackKeyState(next) {
"use strict";
var state = [];
return function (evt) {
var last = state.length !== 0 ? state[state.length-1] : null;
switch (evt.type) {
case 'keydown':
// insert a new entry if last seen key was different.
if (!last || !evt.keyId || last.keyId !== evt.keyId) {
last = {keyId: evt.keyId, keysyms: {}};
state.push(last);
}
if (evt.keysym) {
// make sure last event contains this keysym (a single "logical" keyevent
// can cause multiple key events to be sent to the VNC server)
last.keysyms[evt.keysym.keysym] = evt.keysym;
last.ignoreKeyPress = true;
next(evt);
}
break;
case 'keypress':
if (!last) {
last = {keyId: evt.keyId, keysyms: {}};
state.push(last);
}
if (!evt.keysym) {
console.log('keypress with no keysym:', evt);
}
// If we didn't expect a keypress, and already sent a keydown to the VNC server
// based on the keydown, make sure to skip this event.
if (evt.keysym && !last.ignoreKeyPress) {
last.keysyms[evt.keysym.keysym] = evt.keysym;
evt.type = 'keydown';
next(evt);
}
break;
case 'keyup':
if (state.length === 0) {
return;
}
var idx = null;
// do we have a matching key tracked as being down?
for (var i = 0; i !== state.length; ++i) {
if (state[i].keyId === evt.keyId) {
idx = i;
break;
}
}
// if we couldn't find a match (it happens), assume it was the last key pressed
if (idx === null) {
idx = state.length - 1;
}
var item = state.splice(idx, 1)[0];
// for each keysym tracked by this key entry, clone the current event and override the keysym
var clone = (function(){
function Clone(){}
return function (obj) { Clone.prototype=obj; return new Clone(); };
}());
for (var key in item.keysyms) {
var out = clone(evt);
out.keysym = item.keysyms[key];
next(out);
}
break;
case 'releaseall':
/* jshint shadow: true */
for (var i = 0; i < state.length; ++i) {
for (var key in state[i].keysyms) {
var keysym = state[i].keysyms[key];
next({keyId: 0, keysym: keysym, type: 'keyup'});
}
}
/* jshint shadow: false */
state = [];
}
};
}
// Handles "escaping" of modifiers: if a char modifier is used to produce a keysym (such as AltGr-2 to generate an @),
// then the modifier must be "undone" before sending the @, and "redone" afterwards.
function EscapeModifiers(next) {
"use strict";
return function(evt) {
if (evt.type !== 'keydown' || evt.escape === undefined) {
next(evt);
return;
}
// undo modifiers
for (var i = 0; i < evt.escape.length; ++i) {
next({type: 'keyup', keyId: 0, keysym: keysyms.lookup(evt.escape[i])});
}
// send the character event
next(evt);
// redo modifiers
/* jshint shadow: true */
for (var i = 0; i < evt.escape.length; ++i) {
next({type: 'keydown', keyId: 0, keysym: keysyms.lookup(evt.escape[i])});
}
/* jshint shadow: false */
};
}