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gst-plugins-rs/net/webrtc/gstwebrtc-api/third-party/Keyboard.js

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webrtc: Add gstwebrtc-api subproject in net/webrtc plugin This subproject adds a high-level web API compatible with GStreamer webrtcsrc and webrtcsink elements and the corresponding signaling server. It allows a perfect bidirectional communication between HTML5 WebRTC API and native GStreamer. Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/946>
2022-10-18 16:46:35 +00:00
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
const Guacamole = {};
export { Guacamole as default };
/**
* Provides cross-browser and cross-keyboard keyboard for a specific element.
* Browser and keyboard layout variation is abstracted away, providing events
* which represent keys as their corresponding X11 keysym.
*
* @constructor
* @param {Element|Document} [element]
* The Element to use to provide keyboard events. If omitted, at least one
* Element must be manually provided through the listenTo() function for
* the Guacamole.Keyboard instance to have any effect.
*/
Guacamole.Keyboard = function Keyboard(element) {
/**
* Reference to this Guacamole.Keyboard.
*
* @private
* @type {!Guacamole.Keyboard}
*/
var guac_keyboard = this;
/**
* An integer value which uniquely identifies this Guacamole.Keyboard
* instance with respect to other Guacamole.Keyboard instances.
*
* @private
* @type {!number}
*/
var guacKeyboardID = Guacamole.Keyboard._nextID++;
/**
* The name of the property which is added to event objects via markEvent()
* to note that they have already been handled by this Guacamole.Keyboard.
*
* @private
* @constant
* @type {!string}
*/
var EVENT_MARKER = '_GUAC_KEYBOARD_HANDLED_BY_' + guacKeyboardID;
/**
* Fired whenever the user presses a key with the element associated
* with this Guacamole.Keyboard in focus.
*
* @event
* @param {!number} keysym
* The keysym of the key being pressed.
*
* @return {!boolean}
* true if the key event should be allowed through to the browser,
* false otherwise.
*/
this.onkeydown = null;
/**
* Fired whenever the user releases a key with the element associated
* with this Guacamole.Keyboard in focus.
*
* @event
* @param {!number} keysym
* The keysym of the key being released.
*/
this.onkeyup = null;
/**
* Set of known platform-specific or browser-specific quirks which must be
* accounted for to properly interpret key events, even if the only way to
* reliably detect that quirk is to platform/browser-sniff.
*
* @private
* @type {!Object.<string, boolean>}
*/
var quirks = {
/**
* Whether keyup events are universally unreliable.
*
* @type {!boolean}
*/
keyupUnreliable: false,
/**
* Whether the Alt key is actually a modifier for typable keys and is
* thus never used for keyboard shortcuts.
*
* @type {!boolean}
*/
altIsTypableOnly: false,
/**
* Whether we can rely on receiving a keyup event for the Caps Lock
* key.
*
* @type {!boolean}
*/
capsLockKeyupUnreliable: false
};
// Set quirk flags depending on platform/browser, if such information is
// available
if (navigator && navigator.platform) {
// All keyup events are unreliable on iOS (sadly)
if (navigator.platform.match(/ipad|iphone|ipod/i))
quirks.keyupUnreliable = true;
// The Alt key on Mac is never used for keyboard shortcuts, and the
// Caps Lock key never dispatches keyup events
else if (navigator.platform.match(/^mac/i)) {
quirks.altIsTypableOnly = true;
quirks.capsLockKeyupUnreliable = true;
}
}
/**
* A key event having a corresponding timestamp. This event is non-specific.
* Its subclasses should be used instead when recording specific key
* events.
*
* @private
* @constructor
* @param {KeyboardEvent} [orig]
* The relevant DOM keyboard event.
*/
var KeyEvent = function KeyEvent(orig) {
/**
* Reference to this key event.
*
* @private
* @type {!KeyEvent}
*/
var key_event = this;
/**
* The JavaScript key code of the key pressed. For most events (keydown
* and keyup), this is a scancode-like value related to the position of
* the key on the US English "Qwerty" keyboard. For keypress events,
* this is the Unicode codepoint of the character that would be typed
* by the key pressed.
*
* @type {!number}
*/
this.keyCode = orig ? (orig.which || orig.keyCode) : 0;
/**
* The legacy DOM3 "keyIdentifier" of the key pressed, as defined at:
* http://www.w3.org/TR/2009/WD-DOM-Level-3-Events-20090908/#events-Events-KeyboardEvent
*
* @type {!string}
*/
this.keyIdentifier = orig && orig.keyIdentifier;
/**
* The standard name of the key pressed, as defined at:
* http://www.w3.org/TR/DOM-Level-3-Events/#events-KeyboardEvent
*
* @type {!string}
*/
this.key = orig && orig.key;
/**
* The location on the keyboard corresponding to the key pressed, as
* defined at:
* http://www.w3.org/TR/DOM-Level-3-Events/#events-KeyboardEvent
*
* @type {!number}
*/
this.location = orig ? getEventLocation(orig) : 0;
/**
* The state of all local keyboard modifiers at the time this event was
* received.
*
* @type {!Guacamole.Keyboard.ModifierState}
*/
this.modifiers = orig ? Guacamole.Keyboard.ModifierState.fromKeyboardEvent(orig) : new Guacamole.Keyboard.ModifierState();
/**
* An arbitrary timestamp in milliseconds, indicating this event's
* position in time relative to other events.
*
* @type {!number}
*/
this.timestamp = new Date().getTime();
/**
* Whether the default action of this key event should be prevented.
*
* @type {!boolean}
*/
this.defaultPrevented = false;
/**
* The keysym of the key associated with this key event, as determined
* by a best-effort guess using available event properties and keyboard
* state.
*
* @type {number}
*/
this.keysym = null;
/**
* Whether the keysym value of this key event is known to be reliable.
* If false, the keysym may still be valid, but it's only a best guess,
* and future key events may be a better source of information.
*
* @type {!boolean}
*/
this.reliable = false;
/**
* Returns the number of milliseconds elapsed since this event was
* received.
*
* @return {!number}
* The number of milliseconds elapsed since this event was
* received.
*/
this.getAge = function() {
return new Date().getTime() - key_event.timestamp;
};
};
/**
* Information related to the pressing of a key, which need not be a key
* associated with a printable character. The presence or absence of any
* information within this object is browser-dependent.
*
* @private
* @constructor
* @augments Guacamole.Keyboard.KeyEvent
* @param {!KeyboardEvent} orig
* The relevant DOM "keydown" event.
*/
var KeydownEvent = function KeydownEvent(orig) {
// We extend KeyEvent
KeyEvent.call(this, orig);
// If key is known from keyCode or DOM3 alone, use that
this.keysym = keysym_from_key_identifier(this.key, this.location)
|| keysym_from_keycode(this.keyCode, this.location);
/**
* Whether the keyup following this keydown event is known to be
* reliable. If false, we cannot rely on the keyup event to occur.
*
* @type {!boolean}
*/
this.keyupReliable = !quirks.keyupUnreliable;
// DOM3 and keyCode are reliable sources if the corresponding key is
// not a printable key
if (this.keysym && !isPrintable(this.keysym))
this.reliable = true;
// Use legacy keyIdentifier as a last resort, if it looks sane
if (!this.keysym && key_identifier_sane(this.keyCode, this.keyIdentifier))
this.keysym = keysym_from_key_identifier(this.keyIdentifier, this.location, this.modifiers.shift);
// If a key is pressed while meta is held down, the keyup will
// never be sent in Chrome (bug #108404)
if (this.modifiers.meta && this.keysym !== 0xFFE7 && this.keysym !== 0xFFE8)
this.keyupReliable = false;
// We cannot rely on receiving keyup for Caps Lock on certain platforms
else if (this.keysym === 0xFFE5 && quirks.capsLockKeyupUnreliable)
this.keyupReliable = false;
// Determine whether default action for Alt+combinations must be prevented
var prevent_alt = !this.modifiers.ctrl && !quirks.altIsTypableOnly;
// Determine whether default action for Ctrl+combinations must be prevented
var prevent_ctrl = !this.modifiers.alt;
// We must rely on the (potentially buggy) keyIdentifier if preventing
// the default action is important
if ((prevent_ctrl && this.modifiers.ctrl)
|| (prevent_alt && this.modifiers.alt)
|| this.modifiers.meta
|| this.modifiers.hyper)
this.reliable = true;
// Record most recently known keysym by associated key code
recentKeysym[this.keyCode] = this.keysym;
};
KeydownEvent.prototype = new KeyEvent();
/**
* Information related to the pressing of a key, which MUST be
* associated with a printable character. The presence or absence of any
* information within this object is browser-dependent.
*
* @private
* @constructor
* @augments Guacamole.Keyboard.KeyEvent
* @param {!KeyboardEvent} orig
* The relevant DOM "keypress" event.
*/
var KeypressEvent = function KeypressEvent(orig) {
// We extend KeyEvent
KeyEvent.call(this, orig);
// Pull keysym from char code
this.keysym = keysym_from_charcode(this.keyCode);
// Keypress is always reliable
this.reliable = true;
};
KeypressEvent.prototype = new KeyEvent();
/**
* Information related to the releasing of a key, which need not be a key
* associated with a printable character. The presence or absence of any
* information within this object is browser-dependent.
*
* @private
* @constructor
* @augments Guacamole.Keyboard.KeyEvent
* @param {!KeyboardEvent} orig
* The relevant DOM "keyup" event.
*/
var KeyupEvent = function KeyupEvent(orig) {
// We extend KeyEvent
KeyEvent.call(this, orig);
// If key is known from keyCode or DOM3 alone, use that (keyCode is
// still more reliable for keyup when dead keys are in use)
this.keysym = keysym_from_keycode(this.keyCode, this.location)
|| keysym_from_key_identifier(this.key, this.location);
// Fall back to the most recently pressed keysym associated with the
// keyCode if the inferred key doesn't seem to actually be pressed
if (!guac_keyboard.pressed[this.keysym])
this.keysym = recentKeysym[this.keyCode] || this.keysym;
// Keyup is as reliable as it will ever be
this.reliable = true;
};
KeyupEvent.prototype = new KeyEvent();
/**
* An array of recorded events, which can be instances of the private
* KeydownEvent, KeypressEvent, and KeyupEvent classes.
*
* @private
* @type {!KeyEvent[]}
*/
var eventLog = [];
/**
* Map of known JavaScript keycodes which do not map to typable characters
* to their X11 keysym equivalents.
*
* @private
* @type {!Object.<number, number[]>}
*/
var keycodeKeysyms = {
8: [0xFF08], // backspace
9: [0xFF09], // tab
12: [0xFF0B, 0xFF0B, 0xFF0B, 0xFFB5], // clear / KP 5
13: [0xFF0D], // enter
16: [0xFFE1, 0xFFE1, 0xFFE2], // shift
17: [0xFFE3, 0xFFE3, 0xFFE4], // ctrl
18: [0xFFE9, 0xFFE9, 0xFE03], // alt
19: [0xFF13], // pause/break
20: [0xFFE5], // caps lock
27: [0xFF1B], // escape
32: [0x0020], // space
33: [0xFF55, 0xFF55, 0xFF55, 0xFFB9], // page up / KP 9
34: [0xFF56, 0xFF56, 0xFF56, 0xFFB3], // page down / KP 3
35: [0xFF57, 0xFF57, 0xFF57, 0xFFB1], // end / KP 1
36: [0xFF50, 0xFF50, 0xFF50, 0xFFB7], // home / KP 7
37: [0xFF51, 0xFF51, 0xFF51, 0xFFB4], // left arrow / KP 4
38: [0xFF52, 0xFF52, 0xFF52, 0xFFB8], // up arrow / KP 8
39: [0xFF53, 0xFF53, 0xFF53, 0xFFB6], // right arrow / KP 6
40: [0xFF54, 0xFF54, 0xFF54, 0xFFB2], // down arrow / KP 2
45: [0xFF63, 0xFF63, 0xFF63, 0xFFB0], // insert / KP 0
46: [0xFFFF, 0xFFFF, 0xFFFF, 0xFFAE], // delete / KP decimal
91: [0xFFE7], // left windows/command key (meta_l)
92: [0xFFE8], // right window/command key (meta_r)
93: [0xFF67], // menu key
96: [0xFFB0], // KP 0
97: [0xFFB1], // KP 1
98: [0xFFB2], // KP 2
99: [0xFFB3], // KP 3
100: [0xFFB4], // KP 4
101: [0xFFB5], // KP 5
102: [0xFFB6], // KP 6
103: [0xFFB7], // KP 7
104: [0xFFB8], // KP 8
105: [0xFFB9], // KP 9
106: [0xFFAA], // KP multiply
107: [0xFFAB], // KP add
109: [0xFFAD], // KP subtract
110: [0xFFAE], // KP decimal
111: [0xFFAF], // KP divide
112: [0xFFBE], // f1
113: [0xFFBF], // f2
114: [0xFFC0], // f3
115: [0xFFC1], // f4
116: [0xFFC2], // f5
117: [0xFFC3], // f6
118: [0xFFC4], // f7
119: [0xFFC5], // f8
120: [0xFFC6], // f9
121: [0xFFC7], // f10
122: [0xFFC8], // f11
123: [0xFFC9], // f12
144: [0xFF7F], // num lock
145: [0xFF14], // scroll lock
225: [0xFE03] // altgraph (iso_level3_shift)
};
/**
* Map of known JavaScript keyidentifiers which do not map to typable
* characters to their unshifted X11 keysym equivalents.
*
* @private
* @type {!Object.<string, number[]>}
*/
var keyidentifier_keysym = {
"Again": [0xFF66],
"AllCandidates": [0xFF3D],
"Alphanumeric": [0xFF30],
"Alt": [0xFFE9, 0xFFE9, 0xFE03],
"Attn": [0xFD0E],
"AltGraph": [0xFE03],
"ArrowDown": [0xFF54],
"ArrowLeft": [0xFF51],
"ArrowRight": [0xFF53],
"ArrowUp": [0xFF52],
"Backspace": [0xFF08],
"CapsLock": [0xFFE5],
"Cancel": [0xFF69],
"Clear": [0xFF0B],
"Convert": [0xFF21],
"Copy": [0xFD15],
"Crsel": [0xFD1C],
"CrSel": [0xFD1C],
"CodeInput": [0xFF37],
"Compose": [0xFF20],
"Control": [0xFFE3, 0xFFE3, 0xFFE4],
"ContextMenu": [0xFF67],
"Delete": [0xFFFF],
"Down": [0xFF54],
"End": [0xFF57],
"Enter": [0xFF0D],
"EraseEof": [0xFD06],
"Escape": [0xFF1B],
"Execute": [0xFF62],
"Exsel": [0xFD1D],
"ExSel": [0xFD1D],
"F1": [0xFFBE],
"F2": [0xFFBF],
"F3": [0xFFC0],
"F4": [0xFFC1],
"F5": [0xFFC2],
"F6": [0xFFC3],
"F7": [0xFFC4],
"F8": [0xFFC5],
"F9": [0xFFC6],
"F10": [0xFFC7],
"F11": [0xFFC8],
"F12": [0xFFC9],
"F13": [0xFFCA],
"F14": [0xFFCB],
"F15": [0xFFCC],
"F16": [0xFFCD],
"F17": [0xFFCE],
"F18": [0xFFCF],
"F19": [0xFFD0],
"F20": [0xFFD1],
"F21": [0xFFD2],
"F22": [0xFFD3],
"F23": [0xFFD4],
"F24": [0xFFD5],
"Find": [0xFF68],
"GroupFirst": [0xFE0C],
"GroupLast": [0xFE0E],
"GroupNext": [0xFE08],
"GroupPrevious": [0xFE0A],
"FullWidth": null,
"HalfWidth": null,
"HangulMode": [0xFF31],
"Hankaku": [0xFF29],
"HanjaMode": [0xFF34],
"Help": [0xFF6A],
"Hiragana": [0xFF25],
"HiraganaKatakana": [0xFF27],
"Home": [0xFF50],
"Hyper": [0xFFED, 0xFFED, 0xFFEE],
"Insert": [0xFF63],
"JapaneseHiragana": [0xFF25],
"JapaneseKatakana": [0xFF26],
"JapaneseRomaji": [0xFF24],
"JunjaMode": [0xFF38],
"KanaMode": [0xFF2D],
"KanjiMode": [0xFF21],
"Katakana": [0xFF26],
"Left": [0xFF51],
"Meta": [0xFFE7, 0xFFE7, 0xFFE8],
"ModeChange": [0xFF7E],
"NumLock": [0xFF7F],
"PageDown": [0xFF56],
"PageUp": [0xFF55],
"Pause": [0xFF13],
"Play": [0xFD16],
"PreviousCandidate": [0xFF3E],
"PrintScreen": [0xFF61],
"Redo": [0xFF66],
"Right": [0xFF53],
"RomanCharacters": null,
"Scroll": [0xFF14],
"Select": [0xFF60],
"Separator": [0xFFAC],
"Shift": [0xFFE1, 0xFFE1, 0xFFE2],
"SingleCandidate": [0xFF3C],
"Super": [0xFFEB, 0xFFEB, 0xFFEC],
"Tab": [0xFF09],
"UIKeyInputDownArrow": [0xFF54],
"UIKeyInputEscape": [0xFF1B],
"UIKeyInputLeftArrow": [0xFF51],
"UIKeyInputRightArrow": [0xFF53],
"UIKeyInputUpArrow": [0xFF52],
"Up": [0xFF52],
"Undo": [0xFF65],
"Win": [0xFFE7, 0xFFE7, 0xFFE8],
"Zenkaku": [0xFF28],
"ZenkakuHankaku": [0xFF2A]
};
/**
* All keysyms which should not repeat when held down.
*
* @private
* @type {!Object.<number, boolean>}
*/
var no_repeat = {
0xFE03: true, // ISO Level 3 Shift (AltGr)
0xFFE1: true, // Left shift
0xFFE2: true, // Right shift
0xFFE3: true, // Left ctrl
0xFFE4: true, // Right ctrl
0xFFE5: true, // Caps Lock
0xFFE7: true, // Left meta
0xFFE8: true, // Right meta
0xFFE9: true, // Left alt
0xFFEA: true, // Right alt
0xFFEB: true, // Left super/hyper
0xFFEC: true // Right super/hyper
};
/**
* All modifiers and their states.
*
* @type {!Guacamole.Keyboard.ModifierState}
*/
this.modifiers = new Guacamole.Keyboard.ModifierState();
/**
* The state of every key, indexed by keysym. If a particular key is
* pressed, the value of pressed for that keysym will be true. If a key
* is not currently pressed, it will not be defined.
*
* @type {!Object.<number, boolean>}
*/
this.pressed = {};
/**
* The state of every key, indexed by keysym, for strictly those keys whose
* status has been indirectly determined thorugh observation of other key
* events. If a particular key is implicitly pressed, the value of
* implicitlyPressed for that keysym will be true. If a key
* is not currently implicitly pressed (the key is not pressed OR the state
* of the key is explicitly known), it will not be defined.
*
* @private
* @type {!Object.<number, boolean>}
*/
var implicitlyPressed = {};
/**
* The last result of calling the onkeydown handler for each key, indexed
* by keysym. This is used to prevent/allow default actions for key events,
* even when the onkeydown handler cannot be called again because the key
* is (theoretically) still pressed.
*
* @private
* @type {!Object.<number, boolean>}
*/
var last_keydown_result = {};
/**
* The keysym most recently associated with a given keycode when keydown
* fired. This object maps keycodes to keysyms.
*
* @private
* @type {!Object.<number, number>}
*/
var recentKeysym = {};
/**
* Timeout before key repeat starts.
*
* @private
* @type {number}
*/
var key_repeat_timeout = null;
/**
* Interval which presses and releases the last key pressed while that
* key is still being held down.
*
* @private
* @type {number}
*/
var key_repeat_interval = null;
/**
* Given an array of keysyms indexed by location, returns the keysym
* for the given location, or the keysym for the standard location if
* undefined.
*
* @private
* @param {number[]} keysyms
* An array of keysyms, where the index of the keysym in the array is
* the location value.
*
* @param {!number} location
* The location on the keyboard corresponding to the key pressed, as
* defined at: http://www.w3.org/TR/DOM-Level-3-Events/#events-KeyboardEvent
*/
var get_keysym = function get_keysym(keysyms, location) {
if (!keysyms)
return null;
return keysyms[location] || keysyms[0];
};
/**
* Returns true if the given keysym corresponds to a printable character,
* false otherwise.
*
* @param {!number} keysym
* The keysym to check.
*
* @returns {!boolean}
* true if the given keysym corresponds to a printable character,
* false otherwise.
*/
var isPrintable = function isPrintable(keysym) {
// Keysyms with Unicode equivalents are printable
return (keysym >= 0x00 && keysym <= 0xFF)
|| (keysym & 0xFFFF0000) === 0x01000000;
};
function keysym_from_key_identifier(identifier, location, shifted) {
if (!identifier)
return null;
var typedCharacter;
// If identifier is U+xxxx, decode Unicode character
var unicodePrefixLocation = identifier.indexOf("U+");
if (unicodePrefixLocation >= 0) {
var hex = identifier.substring(unicodePrefixLocation+2);
typedCharacter = String.fromCharCode(parseInt(hex, 16));
}
// If single character and not keypad, use that as typed character
else if (identifier.length === 1 && location !== 3)
typedCharacter = identifier;
// Otherwise, look up corresponding keysym
else
return get_keysym(keyidentifier_keysym[identifier], location);
// Alter case if necessary
if (shifted === true)
typedCharacter = typedCharacter.toUpperCase();
else if (shifted === false)
typedCharacter = typedCharacter.toLowerCase();
// Get codepoint
var codepoint = typedCharacter.charCodeAt(0);
return keysym_from_charcode(codepoint);
}
function isControlCharacter(codepoint) {
return codepoint <= 0x1F || (codepoint >= 0x7F && codepoint <= 0x9F);
}
function keysym_from_charcode(codepoint) {
// Keysyms for control characters
if (isControlCharacter(codepoint)) return 0xFF00 | codepoint;
// Keysyms for ASCII chars
if (codepoint >= 0x0000 && codepoint <= 0x00FF)
return codepoint;
// Keysyms for Unicode
if (codepoint >= 0x0100 && codepoint <= 0x10FFFF)
return 0x01000000 | codepoint;
return null;
}
function keysym_from_keycode(keyCode, location) {
return get_keysym(keycodeKeysyms[keyCode], location);
}
/**
* Heuristically detects if the legacy keyIdentifier property of
* a keydown/keyup event looks incorrectly derived. Chrome, and
* presumably others, will produce the keyIdentifier by assuming
* the keyCode is the Unicode codepoint for that key. This is not
* correct in all cases.
*
* @private
* @param {!number} keyCode
* The keyCode from a browser keydown/keyup event.
*
* @param {string} keyIdentifier
* The legacy keyIdentifier from a browser keydown/keyup event.
*
* @returns {!boolean}
* true if the keyIdentifier looks sane, false if the keyIdentifier
* appears incorrectly derived or is missing entirely.
*/
var key_identifier_sane = function key_identifier_sane(keyCode, keyIdentifier) {
// Missing identifier is not sane
if (!keyIdentifier)
return false;
// Assume non-Unicode keyIdentifier values are sane
var unicodePrefixLocation = keyIdentifier.indexOf("U+");
if (unicodePrefixLocation === -1)
return true;
// If the Unicode codepoint isn't identical to the keyCode,
// then the identifier is likely correct
var codepoint = parseInt(keyIdentifier.substring(unicodePrefixLocation+2), 16);
if (keyCode !== codepoint)
return true;
// The keyCodes for A-Z and 0-9 are actually identical to their
// Unicode codepoints
if ((keyCode >= 65 && keyCode <= 90) || (keyCode >= 48 && keyCode <= 57))
return true;
// The keyIdentifier does NOT appear sane
return false;
};
/**
* Marks a key as pressed, firing the keydown event if registered. Key
* repeat for the pressed key will start after a delay if that key is
* not a modifier. The return value of this function depends on the
* return value of the keydown event handler, if any.
*
* @param {number} keysym
* The keysym of the key to press.
*
* @return {boolean}
* true if event should NOT be canceled, false otherwise.
*/
this.press = function(keysym) {
// Don't bother with pressing the key if the key is unknown
if (keysym === null) return;
// Only press if released
if (!guac_keyboard.pressed[keysym]) {
// Mark key as pressed
guac_keyboard.pressed[keysym] = true;
// Send key event
if (guac_keyboard.onkeydown) {
var result = guac_keyboard.onkeydown(keysym);
last_keydown_result[keysym] = result;
// Stop any current repeat
window.clearTimeout(key_repeat_timeout);
window.clearInterval(key_repeat_interval);
// Repeat after a delay as long as pressed
if (!no_repeat[keysym])
key_repeat_timeout = window.setTimeout(function() {
key_repeat_interval = window.setInterval(function() {
guac_keyboard.onkeyup(keysym);
guac_keyboard.onkeydown(keysym);
}, 50);
}, 500);
return result;
}
}
// Return the last keydown result by default, resort to false if unknown
return last_keydown_result[keysym] || false;
};
/**
* Marks a key as released, firing the keyup event if registered.
*
* @param {number} keysym
* The keysym of the key to release.
*/
this.release = function(keysym) {
// Only release if pressed
if (guac_keyboard.pressed[keysym]) {
// Mark key as released
delete guac_keyboard.pressed[keysym];
delete implicitlyPressed[keysym];
// Stop repeat
window.clearTimeout(key_repeat_timeout);
window.clearInterval(key_repeat_interval);
// Send key event
if (keysym !== null && guac_keyboard.onkeyup)
guac_keyboard.onkeyup(keysym);
}
};
/**
* Presses and releases the keys necessary to type the given string of
* text.
*
* @param {!string} str
* The string to type.
*/
this.type = function type(str) {
// Press/release the key corresponding to each character in the string
for (var i = 0; i < str.length; i++) {
// Determine keysym of current character
var codepoint = str.codePointAt ? str.codePointAt(i) : str.charCodeAt(i);
var keysym = keysym_from_charcode(codepoint);
// Press and release key for current character
guac_keyboard.press(keysym);
guac_keyboard.release(keysym);
}
};
/**
* Resets the state of this keyboard, releasing all keys, and firing keyup
* events for each released key.
*/
this.reset = function() {
// Release all pressed keys
for (var keysym in guac_keyboard.pressed)
guac_keyboard.release(parseInt(keysym));
// Clear event log
eventLog = [];
};
/**
* Resynchronizes the remote state of the given modifier with its
* corresponding local modifier state, as dictated by
* {@link KeyEvent#modifiers} within the given key event, by pressing or
* releasing keysyms.
*
* @private
* @param {!string} modifier
* The name of the {@link Guacamole.Keyboard.ModifierState} property
* being updated.
*
* @param {!number[]} keysyms
* The keysyms which represent the modifier being updated.
*
* @param {!KeyEvent} keyEvent
* Guacamole's current best interpretation of the key event being
* processed.
*/
var updateModifierState = function updateModifierState(modifier,
keysyms, keyEvent) {
var localState = keyEvent.modifiers[modifier];
var remoteState = guac_keyboard.modifiers[modifier];
var i;
// Do not trust changes in modifier state for events directly involving
// that modifier: (1) the flag may erroneously be cleared despite
// another version of the same key still being held and (2) the change
// in flag may be due to the current event being processed, thus
// updating things here is at best redundant and at worst incorrect
if (keysyms.indexOf(keyEvent.keysym) !== -1)
return;
// Release all related keys if modifier is implicitly released
if (remoteState && localState === false) {
for (i = 0; i < keysyms.length; i++) {
guac_keyboard.release(keysyms[i]);
}
}
// Press if modifier is implicitly pressed
else if (!remoteState && localState) {
// Verify that modifier flag isn't already pressed or already set
// due to another version of the same key being held down
for (i = 0; i < keysyms.length; i++) {
if (guac_keyboard.pressed[keysyms[i]])
return;
}
// Mark as implicitly pressed only if there is other information
// within the key event relating to a different key. Some
// platforms, such as iOS, will send essentially empty key events
// for modifier keys, using only the modifier flags to signal the
// identity of the key.
var keysym = keysyms[0];
if (keyEvent.keysym)
implicitlyPressed[keysym] = true;
guac_keyboard.press(keysym);
}
};
/**
* Given a keyboard event, updates the remote key state to match the local
* modifier state and remote based on the modifier flags within the event.
* This function pays no attention to keycodes.
*
* @private
* @param {!KeyEvent} keyEvent
* Guacamole's current best interpretation of the key event being
* processed.
*/
var syncModifierStates = function syncModifierStates(keyEvent) {
// Resync state of alt
updateModifierState('alt', [
0xFFE9, // Left alt
0xFFEA, // Right alt
0xFE03 // AltGr
], keyEvent);
// Resync state of shift
updateModifierState('shift', [
0xFFE1, // Left shift
0xFFE2 // Right shift
], keyEvent);
// Resync state of ctrl
updateModifierState('ctrl', [
0xFFE3, // Left ctrl
0xFFE4 // Right ctrl
], keyEvent);
// Resync state of meta
updateModifierState('meta', [
0xFFE7, // Left meta
0xFFE8 // Right meta
], keyEvent);
// Resync state of hyper
updateModifierState('hyper', [
0xFFEB, // Left super/hyper
0xFFEC // Right super/hyper
], keyEvent);
// Update state
guac_keyboard.modifiers = keyEvent.modifiers;
};
/**
* Returns whether all currently pressed keys were implicitly pressed. A
* key is implicitly pressed if its status was inferred indirectly from
* inspection of other key events.
*
* @private
* @returns {!boolean}
* true if all currently pressed keys were implicitly pressed, false
* otherwise.
*/
var isStateImplicit = function isStateImplicit() {
for (var keysym in guac_keyboard.pressed) {
if (!implicitlyPressed[keysym])
return false;
}
return true;
};
/**
* Reads through the event log, removing events from the head of the log
* when the corresponding true key presses are known (or as known as they
* can be).
*
* @private
* @return {boolean}
* Whether the default action of the latest event should be prevented.
*/
function interpret_events() {
// Do not prevent default if no event could be interpreted
var handled_event = interpret_event();
if (!handled_event)
return false;
// Interpret as much as possible
var last_event;
do {
last_event = handled_event;
handled_event = interpret_event();
} while (handled_event !== null);
// Reset keyboard state if we cannot expect to receive any further
// keyup events
if (isStateImplicit())
guac_keyboard.reset();
return last_event.defaultPrevented;
}
/**
* Releases Ctrl+Alt, if both are currently pressed and the given keysym
* looks like a key that may require AltGr.
*
* @private
* @param {!number} keysym
* The key that was just pressed.
*/
var release_simulated_altgr = function release_simulated_altgr(keysym) {
// Both Ctrl+Alt must be pressed if simulated AltGr is in use
if (!guac_keyboard.modifiers.ctrl || !guac_keyboard.modifiers.alt)
return;
// Assume [A-Z] never require AltGr
if (keysym >= 0x0041 && keysym <= 0x005A)
return;
// Assume [a-z] never require AltGr
if (keysym >= 0x0061 && keysym <= 0x007A)
return;
// Release Ctrl+Alt if the keysym is printable
if (keysym <= 0xFF || (keysym & 0xFF000000) === 0x01000000) {
guac_keyboard.release(0xFFE3); // Left ctrl
guac_keyboard.release(0xFFE4); // Right ctrl
guac_keyboard.release(0xFFE9); // Left alt
guac_keyboard.release(0xFFEA); // Right alt
}
};
/**
* Reads through the event log, interpreting the first event, if possible,
* and returning that event. If no events can be interpreted, due to a
* total lack of events or the need for more events, null is returned. Any
* interpreted events are automatically removed from the log.
*
* @private
* @return {KeyEvent}
* The first key event in the log, if it can be interpreted, or null
* otherwise.
*/
var interpret_event = function interpret_event() {
// Peek at first event in log
var first = eventLog[0];
if (!first)
return null;
// Keydown event
if (first instanceof KeydownEvent) {
var keysym = null;
var accepted_events = [];
// Defer handling of Meta until it is known to be functioning as a
// modifier (it may otherwise actually be an alternative method for
// pressing a single key, such as Meta+Left for Home on ChromeOS)
if (first.keysym === 0xFFE7 || first.keysym === 0xFFE8) {
// Defer handling until further events exist to provide context
if (eventLog.length === 1)
return null;
// Drop keydown if it turns out Meta does not actually apply
if (eventLog[1].keysym !== first.keysym) {
if (!eventLog[1].modifiers.meta)
return eventLog.shift();
}
// Drop duplicate keydown events while waiting to determine
// whether to acknowledge Meta (browser may repeat keydown
// while the key is held)
else if (eventLog[1] instanceof KeydownEvent)
return eventLog.shift();
}
// If event itself is reliable, no need to wait for other events
if (first.reliable) {
keysym = first.keysym;
accepted_events = eventLog.splice(0, 1);
}
// If keydown is immediately followed by a keypress, use the indicated character
else if (eventLog[1] instanceof KeypressEvent) {
keysym = eventLog[1].keysym;
accepted_events = eventLog.splice(0, 2);
}
// If keydown is immediately followed by anything else, then no
// keypress can possibly occur to clarify this event, and we must
// handle it now
else if (eventLog[1]) {
keysym = first.keysym;
accepted_events = eventLog.splice(0, 1);
}
// Fire a key press if valid events were found
if (accepted_events.length > 0) {
syncModifierStates(first);
if (keysym) {
// Fire event
release_simulated_altgr(keysym);
var defaultPrevented = !guac_keyboard.press(keysym);
recentKeysym[first.keyCode] = keysym;
// Release the key now if we cannot rely on the associated
// keyup event
if (!first.keyupReliable)
guac_keyboard.release(keysym);
// Record whether default was prevented
for (var i=0; i<accepted_events.length; i++)
accepted_events[i].defaultPrevented = defaultPrevented;
}
return first;
}
} // end if keydown
// Keyup event
else if (first instanceof KeyupEvent && !quirks.keyupUnreliable) {
// Release specific key if known
var keysym = first.keysym;
if (keysym) {
guac_keyboard.release(keysym);
delete recentKeysym[first.keyCode];
first.defaultPrevented = true;
}
// Otherwise, fall back to releasing all keys
else {
guac_keyboard.reset();
return first;
}
syncModifierStates(first);
return eventLog.shift();
} // end if keyup
// Ignore any other type of event (keypress by itself is invalid, and
// unreliable keyup events should simply be dumped)
else
return eventLog.shift();
// No event interpreted
return null;
};
/**
* Returns the keyboard location of the key associated with the given
* keyboard event. The location differentiates key events which otherwise
* have the same keycode, such as left shift vs. right shift.
*
* @private
* @param {!KeyboardEvent} e
* A JavaScript keyboard event, as received through the DOM via a
* "keydown", "keyup", or "keypress" handler.
*
* @returns {!number}
* The location of the key event on the keyboard, as defined at:
* http://www.w3.org/TR/DOM-Level-3-Events/#events-KeyboardEvent
*/
var getEventLocation = function getEventLocation(e) {
// Use standard location, if possible
if ('location' in e)
return e.location;
// Failing that, attempt to use deprecated keyLocation
if ('keyLocation' in e)
return e.keyLocation;
// If no location is available, assume left side
return 0;
};
/**
* Attempts to mark the given Event as having been handled by this
* Guacamole.Keyboard. If the Event has already been marked as handled,
* false is returned.
*
* @param {!Event} e
* The Event to mark.
*
* @returns {!boolean}
* true if the given Event was successfully marked, false if the given
* Event was already marked.
*/
var markEvent = function markEvent(e) {
// Fail if event is already marked
if (e[EVENT_MARKER])
return false;
// Mark event otherwise
e[EVENT_MARKER] = true;
return true;
};
/**
* Attaches event listeners to the given Element, automatically translating
* received key, input, and composition events into simple keydown/keyup
* events signalled through this Guacamole.Keyboard's onkeydown and
* onkeyup handlers.
*
* @param {!(Element|Document)} element
* The Element to attach event listeners to for the sake of handling
* key or input events.
*/
this.listenTo = function listenTo(element) {
// When key pressed
element.addEventListener("keydown", function(e) {
// Only intercept if handler set
if (!guac_keyboard.onkeydown) return;
// Ignore events which have already been handled
if (!markEvent(e)) return;
var keydownEvent = new KeydownEvent(e);
// Ignore (but do not prevent) the "composition" keycode sent by some
// browsers when an IME is in use (see: http://lists.w3.org/Archives/Public/www-dom/2010JulSep/att-0182/keyCode-spec.html)
if (keydownEvent.keyCode === 229)
return;
// Log event
eventLog.push(keydownEvent);
// Interpret as many events as possible, prevent default if indicated
if (interpret_events())
e.preventDefault();
}, true);
// When key pressed
element.addEventListener("keypress", function(e) {
// Only intercept if handler set
if (!guac_keyboard.onkeydown && !guac_keyboard.onkeyup) return;
// Ignore events which have already been handled
if (!markEvent(e)) return;
// Log event
eventLog.push(new KeypressEvent(e));
// Interpret as many events as possible, prevent default if indicated
if (interpret_events())
e.preventDefault();
}, true);
// When key released
element.addEventListener("keyup", function(e) {
// Only intercept if handler set
if (!guac_keyboard.onkeyup) return;
// Ignore events which have already been handled
if (!markEvent(e)) return;
e.preventDefault();
// Log event, call for interpretation
eventLog.push(new KeyupEvent(e));
interpret_events();
}, true);
/**
* Handles the given "input" event, typing the data within the input text.
* If the event is complete (text is provided), handling of "compositionend"
* events is suspended, as such events may conflict with input events.
*
* @private
* @param {!InputEvent} e
* The "input" event to handle.
*/
var handleInput = function handleInput(e) {
// Only intercept if handler set
if (!guac_keyboard.onkeydown && !guac_keyboard.onkeyup) return;
// Ignore events which have already been handled
if (!markEvent(e)) return;
// Type all content written
if (e.data && !e.isComposing) {
element.removeEventListener("compositionend", handleComposition, false);
guac_keyboard.type(e.data);
}
};
/**
* Handles the given "compositionend" event, typing the data within the
* composed text. If the event is complete (composed text is provided),
* handling of "input" events is suspended, as such events may conflict
* with composition events.
*
* @private
* @param {!CompositionEvent} e
* The "compositionend" event to handle.
*/
var handleComposition = function handleComposition(e) {
// Only intercept if handler set
if (!guac_keyboard.onkeydown && !guac_keyboard.onkeyup) return;
// Ignore events which have already been handled
if (!markEvent(e)) return;
// Type all content written
if (e.data) {
element.removeEventListener("input", handleInput, false);
guac_keyboard.type(e.data);
}
};
// Automatically type text entered into the wrapped field
element.addEventListener("input", handleInput, false);
element.addEventListener("compositionend", handleComposition, false);
};
// Listen to given element, if any
if (element)
guac_keyboard.listenTo(element);
};
/**
* The unique numerical identifier to assign to the next Guacamole.Keyboard
* instance.
*
* @private
* @type {!number}
*/
Guacamole.Keyboard._nextID = 0;
/**
* The state of all supported keyboard modifiers.
* @constructor
*/
Guacamole.Keyboard.ModifierState = function() {
/**
* Whether shift is currently pressed.
*
* @type {!boolean}
*/
this.shift = false;
/**
* Whether ctrl is currently pressed.
*
* @type {!boolean}
*/
this.ctrl = false;
/**
* Whether alt is currently pressed.
*
* @type {!boolean}
*/
this.alt = false;
/**
* Whether meta (apple key) is currently pressed.
*
* @type {!boolean}
*/
this.meta = false;
/**
* Whether hyper (windows key) is currently pressed.
*
* @type {!boolean}
*/
this.hyper = false;
};
/**
* Returns the modifier state applicable to the keyboard event given.
*
* @param {!KeyboardEvent} e
* The keyboard event to read.
*
* @returns {!Guacamole.Keyboard.ModifierState}
* The current state of keyboard modifiers.
*/
Guacamole.Keyboard.ModifierState.fromKeyboardEvent = function(e) {
var state = new Guacamole.Keyboard.ModifierState();
// Assign states from old flags
state.shift = e.shiftKey;
state.ctrl = e.ctrlKey;
state.alt = e.altKey;
state.meta = e.metaKey;
// Use DOM3 getModifierState() for others
if (e.getModifierState) {
state.hyper = e.getModifierState("OS")
|| e.getModifierState("Super")
|| e.getModifierState("Hyper")
|| e.getModifierState("Win");
}
return state;
};
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