/*
* Copyright (C) 2015 Glyptodon LLC
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
var Guacamole = Guacamole || {};
/**
* Dynamic on-screen keyboard. Given the layout object for an on-screen
* keyboard, this object will construct a clickable on-screen keyboard with its
* own key events.
*
* @constructor
* @param {Guacamole.OnScreenKeyboard.Layout} layout
* The layout of the on-screen keyboard to display.
*/
Guacamole.OnScreenKeyboard = function(layout) {
/**
* Reference to this Guacamole.OnScreenKeyboard.
*
* @private
* @type {Guacamole.OnScreenKeyboard}
*/
var osk = this;
/**
* Map of currently-set modifiers to the keysym associated with their
* original press. When the modifier is cleared, this keysym must be
* released.
*
* @private
* @type {Object.<String, Number>}
*/
var modifierKeysyms = {};
/**
* Map of all key names to their current pressed states. If a key is not
* pressed, it may not be in this map at all, but all pressed keys will
* have a corresponding mapping to true.
*
* @private
* @type {Object.<String, Boolean>}
*/
var pressed = {};
/**
* All scalable elements which are part of the on-screen keyboard. Each
* scalable element is carefully controlled to ensure the interface layout
* and sizing remains constant, even on browsers that would otherwise
* experience rounding error due to unit conversions.
*
* @private
* @type {ScaledElement[]}
*/
var scaledElements = [];
/**
* Adds a CSS class to an element.
*
* @private
* @function
* @param {Element} element
* The element to add a class to.
*
* @param {String} classname
* The name of the class to add.
*/
var addClass = function addClass(element, classname) {
// If classList supported, use that
if (element.classList)
element.classList.add(classname);
// Otherwise, simply append the class
else
element.className += " " + classname;
};
/**
* Removes a CSS class from an element.
*
* @private
* @function
* @param {Element} element
* The element to remove a class from.
*
* @param {String} classname
* The name of the class to remove.
*/
var removeClass = function removeClass(element, classname) {
// If classList supported, use that
if (element.classList)
element.classList.remove(classname);
// Otherwise, manually filter out classes with given name
else {
element.className = element.className.replace(/([^ ]+)[ ]*/g,
function removeMatchingClasses(match, testClassname) {
// If same class, remove
if (testClassname === classname)
return "";
// Otherwise, allow
return match;
}
);
}
};
/**
* Counter of mouse events to ignore. This decremented by mousemove, and
* while non-zero, mouse events will have no effect.
*
* @private
* @type {Number}
*/
var ignoreMouse = 0;
/**
* Ignores all pending mouse events when touch events are the apparent
* source. Mouse events are ignored until at least touchMouseThreshold
* mouse events occur without corresponding touch events.
*
* @private
*/
var ignorePendingMouseEvents = function ignorePendingMouseEvents() {
ignoreMouse = osk.touchMouseThreshold;
};
/**
* An element whose dimensions are maintained according to an arbitrary
* scale. The conversion factor for these arbitrary units to pixels is
* provided later via a call to scale().
*
* @private
* @constructor
* @param {Element} element
* The element whose scale should be maintained.
*
* @param {Number} width
* The width of the element, in arbitrary units, relative to other
* ScaledElements.
*
* @param {Number} height
* The height of the element, in arbitrary units, relative to other
* ScaledElements.
*
* @param {Boolean} [scaleFont=false]
* Whether the line height and font size should be scaled as well.
*/
var ScaledElement = function ScaledElement(element, width, height, scaleFont) {
/**
* The width of this ScaledElement, in arbitrary units, relative to
* other ScaledElements.
*
* @type {Number}
*/
this.width = width;
/**
* The height of this ScaledElement, in arbitrary units, relative to
* other ScaledElements.
*
* @type {Number}
*/
this.height = height;
/**
* Resizes the associated element, updating its dimensions according to
* the given pixels per unit.
*
* @param {Number} pixels
* The number of pixels to assign per arbitrary unit.
*/
this.scale = function(pixels) {
// Scale element width/height
element.style.width = (width * pixels) + "px";
element.style.height = (height * pixels) + "px";
// Scale font, if requested
if (scaleFont) {
element.style.lineHeight = (height * pixels) + "px";
element.style.fontSize = pixels + "px";
}
};
};
/**
* Returns whether all modifiers having the given names are currently
* active.
*
* @private
* @param {String[]} names
* The names of all modifiers to test.
*
* @returns {Boolean}
* true if all specified modifiers are pressed, false otherwise.
*/
var modifiersPressed = function modifiersPressed(names) {
// If any required modifiers are not pressed, return false
for (var i=0; i < names.length; i++) {
// Test whether current modifier is pressed
var name = names[i];
if (!(name in modifierKeysyms))
return false;
}
// Otherwise, all required modifiers are pressed
return true;
};
/**
* Returns the single matching Key object associated with the key of the
* given name, where that Key object's requirements (such as pressed
* modifiers) are all currently satisfied.
*
* @private
* @param {String} keyName
* The name of the key to retrieve.
*
* @returns {Guacamole.OnScreenKeyboard.Key}
* The Key object associated with the given name, where that object's
* requirements are all currently satisfied, or null if no such Key
* can be found.
*/
var getActiveKey = function getActiveKey(keyName) {
// Get key array for given name
var keys = osk.keys[keyName];
if (!keys)
return null;
// Find last matching key
for (var i = keys.length - 1; i >= 0; i--) {
// Get candidate key
var candidate = keys[i];
// If all required modifiers are pressed, use that key
if (modifiersPressed(candidate.requires))
return candidate;
}
// No valid key
return null;
};
/**
* Presses the key having the given name, updating the associated key
* element with the "guac-keyboard-pressed" CSS class. If the key is
* already pressed, this function has no effect.
*
* @private
* @param {String} keyName
* The name of the key to press.
*
* @param {String} keyElement
* The element associated with the given key.
*/
var press = function press(keyName, keyElement) {
// Press key if not yet pressed
if (!pressed[keyName]) {
addClass(keyElement, "guac-keyboard-pressed");
// Get current key based on modifier state
var key = getActiveKey(keyName);
// Update modifier state
if (key.modifier) {
// Construct classname for modifier
var modifierClass = "guac-keyboard-modifier-" + getCSSName(key.modifier);
// Retrieve originally-pressed keysym, if modifier was already pressed
var originalKeysym = modifierKeysyms[key.modifier];
// Activate modifier if not pressed
if (!originalKeysym) {
addClass(keyboard, modifierClass);
modifierKeysyms[key.modifier] = key.keysym;
// Send key event
if (osk.onkeydown)
osk.onkeydown(key.keysym);
}
// Deactivate if not pressed
else {
removeClass(keyboard, modifierClass);
delete modifierKeysyms[key.modifier];
// Send key event
if (osk.onkeyup)
osk.onkeyup(originalKeysym);
}
}
// If not modifier, send key event now
else if (osk.onkeydown)
osk.onkeydown(key.keysym);
// Mark key as pressed
pressed[keyName] = true;
}
};
/**
* Releases the key having the given name, removing the
* "guac-keyboard-pressed" CSS class from the associated element. If the
* key is already released, this function has no effect.
*
* @private
* @param {String} keyName
* The name of the key to release.
*
* @param {String} keyElement
* The element associated with the given key.
*/
var release = function release(keyName, keyElement) {
// Release key if currently pressed
if (pressed[keyName]) {
removeClass(keyElement, "guac-keyboard-pressed");
// Get current key based on modifier state
var key = getActiveKey(keyName);
// Send key event if not a modifier key
if (!key.modifier && osk.onkeyup)
osk.onkeyup(key.keysym);
// Mark key as released
pressed[keyName] = false;
}
};
// Create keyboard
var keyboard = document.createElement("div");
keyboard.className = "guac-keyboard";
// Do not allow selection or mouse movement to propagate/register.
keyboard.onselectstart =
keyboard.onmousemove =
keyboard.onmouseup =
keyboard.onmousedown = function handleMouseEvents(e) {
// If ignoring events, decrement counter
if (ignoreMouse)
ignoreMouse--;
e.stopPropagation();
return false;
};
/**
* The number of mousemove events to require before re-enabling mouse
* event handling after receiving a touch event.
*
* @type {Number}
*/
this.touchMouseThreshold = 3;
/**
* Fired whenever the user presses a key on this Guacamole.OnScreenKeyboard.
*
* @event
* @param {Number} keysym The keysym of the key being pressed.
*/
this.onkeydown = null;
/**
* Fired whenever the user releases a key on this Guacamole.OnScreenKeyboard.
*
* @event
* @param {Number} keysym The keysym of the key being released.
*/
this.onkeyup = null;
/**
* The keyboard layout provided at time of construction.
*
* @type {Guacamole.OnScreenKeyboard.Layout}
*/
this.layout = new Guacamole.OnScreenKeyboard.Layout(layout);
/**
* Returns the element containing the entire on-screen keyboard.
* @returns {Element} The element containing the entire on-screen keyboard.
*/
this.getElement = function() {
return keyboard;
};
/**
* Resizes all elements within this Guacamole.OnScreenKeyboard such that
* the width is close to but does not exceed the specified width. The
* height of the keyboard is determined based on the width.
*
* @param {Number} width The width to resize this Guacamole.OnScreenKeyboard
* to, in pixels.
*/
this.resize = function(width) {
// Get pixel size of a unit
var unit = Math.floor(width * 10 / osk.layout.width) / 10;
// Resize all scaled elements
for (var i=0; i<scaledElements.length; i++) {
var scaledElement = scaledElements[i];
scaledElement.scale(unit);
}
};
/**
* Given the name of a key and its corresponding definition, which may be
* an array of keys objects, a number (keysym), a string (key title), or a
* single key object, returns an array of key objects, deriving any missing
* properties as needed, and ensuring the key name is defined.
*
* @private
* @param {String} name
* The name of the key being coerced into an array of Key objects.
*
* @param {Number|String|Guacamole.OnScreenKeyboard.Key|Guacamole.OnScreenKeyboard.Key[]} object
* The object defining the behavior of the key having the given name,
* which may be the title of the key (a string), the keysym (a number),
* a single Key object, or an array of Key objects.
*
* @returns {Guacamole.OnScreenKeyboard.Key[]}
* An array of all keys associated with the given name.
*/
var asKeyArray = function asKeyArray(name, object) {
// If already an array, just coerce into a true Key[]
if (object instanceof Array) {
var keys = [];
for (var i=0; i < object.length; i++) {
keys.push(new Guacamole.OnScreenKeyboard.Key(object[i], name));
}
return keys;
}
// Derive key object from keysym if that's all we have
if (typeof object === 'number') {
return [new Guacamole.OnScreenKeyboard.Key({
name : name,
keysym : object
})];
}
// Derive key object from title if that's all we have
if (typeof object === 'string') {
return [new Guacamole.OnScreenKeyboard.Key({
name : name,
title : object
})];
}
// Otherwise, assume it's already a key object, just not an array
return [new Guacamole.OnScreenKeyboard.Key(object, name)];
};
/**
* Converts the rather forgiving key mapping allowed by
* Guacamole.OnScreenKeyboard.Layout into a rigorous mapping of key name
* to key definition, where the key definition is always an array of Key
* objects.
*
* @private
* @param {Object.<String, Number|String|Guacamole.OnScreenKeyboard.Key|Guacamole.OnScreenKeyboard.Key[]>} keys
* A mapping of key name to key definition, where the key definition is
* the title of the key (a string), the keysym (a number), a single
* Key object, or an array of Key objects.
*
* @returns {Object.<String, Guacamole.OnScreenKeyboard.Key[]>}
* A more-predictable mapping of key name to key definition, where the
* key definition is always simply an array of Key objects.
*/
var getKeys = function getKeys(keys) {
var keyArrays = {};
// Coerce all keys into individual key arrays
for (var name in layout.keys) {
keyArrays[name] = asKeyArray(name, keys[name]);
}
return keyArrays;
};
/**
* Map of all key names to their corresponding set of keys. Each key name
* may correspond to multiple keys due to the effect of modifiers.
*
* @type {Object.<String, Guacamole.OnScreenKeyboard.Key[]>}
*/
this.keys = getKeys(layout.keys);
/**
* Given an arbitrary string representing the name of some component of the
* on-screen keyboard, returns a string formatted for use as a CSS class
* name. The result will be lowercase. Word boundaries previously denoted
* by CamelCase will be replaced by individual hyphens, as will all
* contiguous non-alphanumeric characters.
*
* @private
* @param {String} name
* An arbitrary string representing the name of some component of the
* on-screen keyboard.
*
* @returns {String}
* A string formatted for use as a CSS class name.
*/
var getCSSName = function getCSSName(name) {
// Convert name from possibly-CamelCase to hyphenated lowercase
var cssName = name
.replace(/([a-z])([A-Z])/g, '$1-$2')
.replace(/[^A-Za-z0-9]+/g, '-')
.toLowerCase();
return cssName;
};
/**
* Appends DOM elements to the given element as dictated by the layout
* structure object provided. If a name is provided, an additional CSS
* class, prepended with "guac-keyboard-", will be added to the top-level
* element.
*
* If the layout structure object is an array, all elements within that
* array will be recursively appended as children of a group, and the
* top-level element will be given the CSS class "guac-keyboard-group".
*
* If the layout structure object is an object, all properties within that
* object will be recursively appended as children of a group, and the
* top-level element will be given the CSS class "guac-keyboard-group". The
* name of each property will be applied as the name of each child object
* for the sake of CSS. Each property will be added in sorted order.
*
* If the layout structure object is a string, the key having that name
* will be appended. The key will be given the CSS class
* "guac-keyboard-key" and "guac-keyboard-key-NAME", where NAME is the name
* of the key. If the name of the key is a single character, this will
* first be transformed into the C-style hexadecimal literal for the
* Unicode codepoint of that character. For example, the key "A" would
* become "guac-keyboard-key-0x41".
*
* If the layout structure object is a number, a gap of that size will be
* inserted. The gap will be given the CSS class "guac-keyboard-gap", and
* will be scaled according to the same size units as each key.
*
* @private
* @param {Element} element
* The element to append elements to.
*
* @param {Array|Object|String|Number} object
* The layout structure object to use when constructing the elements to
* append.
*
* @param {String} [name]
* The name of the top-level element being appended, if any.
*/
var appendElements = function appendElements(element, object, name) {
var i;
// Create div which will become the group or key
var div = document.createElement('div');
// Add class based on name, if name given
if (name)
addClass(div, 'guac-keyboard-' + getCSSName(name));
// If an array, append each element
if (object instanceof Array) {
// Add group class
addClass(div, 'guac-keyboard-group');
// Append all elements of array
for (i=0; i < object.length; i++)
appendElements(div, object[i]);
}
// If an object, append each property value
else if (object instanceof Object) {
// Add group class
addClass(div, 'guac-keyboard-group');
// Append all children, sorted by name
var names = Object.keys(object).sort();
for (i=0; i < names.length; i++) {
var name = names[i];
appendElements(div, object[name], name);
}
}
// If a number, create as a gap
else if (typeof object === 'number') {
// Add gap class
addClass(div, 'guac-keyboard-gap');
// Maintain scale
scaledElements.push(new ScaledElement(div, object, object));
}
// If a string, create as a key
else if (typeof object === 'string') {
// If key name is only one character, use codepoint for name
var keyName = object;
if (keyName.length === 1)
keyName = '0x' + keyName.charCodeAt(0).toString(16);
// Add key container class
addClass(div, 'guac-keyboard-key-container');
// Create key element which will contain all possible caps
var keyElement = document.createElement('div');
keyElement.className = 'guac-keyboard-key '
+ 'guac-keyboard-key-' + getCSSName(keyName);
// Add all associated keys as caps within DOM
var keys = osk.keys[object];
if (keys) {
for (i=0; i < keys.length; i++) {
// Get current key
var key = keys[i];
// Create cap element for key
var capElement = document.createElement('div');
capElement.className = 'guac-keyboard-cap';
capElement.textContent = key.title;
// Add classes for any requirements
for (var j=0; j < key.requires.length; j++) {
var requirement = key.requires[j];
addClass(capElement, 'guac-keyboard-requires-' + getCSSName(requirement));
addClass(keyElement, 'guac-keyboard-uses-' + getCSSName(requirement));
}
// Add cap to key within DOM
keyElement.appendChild(capElement);
}
}
// Add key to DOM, maintain scale
div.appendChild(keyElement);
scaledElements.push(new ScaledElement(div, osk.layout.keyWidths[object] || 1, 1, true));
/**
* Handles a touch event which results in the pressing of an OSK
* key. Touch events will result in mouse events being ignored for
* touchMouseThreshold events.
*
* @private
* @param {TouchEvent} e
* The touch event being handled.
*/
var touchPress = function touchPress(e) {
e.preventDefault();
ignoreMouse = osk.touchMouseThreshold;
press(object, keyElement);
};
/**
* Handles a touch event which results in the release of an OSK
* key. Touch events will result in mouse events being ignored for
* touchMouseThreshold events.
*
* @private
* @param {TouchEvent} e
* The touch event being handled.
*/
var touchRelease = function touchRelease(e) {
e.preventDefault();
ignoreMouse = osk.touchMouseThreshold;
release(object, keyElement);
};
/**
* Handles a mouse event which results in the pressing of an OSK
* key. If mouse events are currently being ignored, this handler
* does nothing.
*
* @private
* @param {MouseEvent} e
* The touch event being handled.
*/
var mousePress = function mousePress(e) {
e.preventDefault();
if (ignoreMouse === 0)
press(object, keyElement);
};
/**
* Handles a mouse event which results in the release of an OSK
* key. If mouse events are currently being ignored, this handler
* does nothing.
*
* @private
* @param {MouseEvent} e
* The touch event being handled.
*/
var mouseRelease = function mouseRelease(e) {
e.preventDefault();
if (ignoreMouse === 0)
release(object, keyElement);
};
// Handle touch events on key
keyElement.addEventListener("touchstart", touchPress, true);
keyElement.addEventListener("touchend", touchRelease, true);
// Handle mouse events on key
keyElement.addEventListener("mousedown", mousePress, true);
keyElement.addEventListener("mouseup", mouseRelease, true);
keyElement.addEventListener("mouseout", mouseRelease, true);
} // end if object is key name
// Add newly-created group/key
element.appendChild(div);
};
// Create keyboard layout in DOM
appendElements(keyboard, layout.layout);
};
/**
* Represents an entire on-screen keyboard layout, including all available
* keys, their behaviors, and their relative position and sizing.
*
* @constructor
* @param {Guacamole.OnScreenKeyboard.Layout|Object} template
* The object whose identically-named properties will be used to initialize
* the properties of this layout.
*/
Guacamole.OnScreenKeyboard.Layout = function(template) {
/**
* The language of keyboard layout, such as "en_US". This property is for
* informational purposes only, but it is recommend to conform to the
* [language code]_[country code] format.
*
* @type {String}
*/
this.language = template.language;
/**
* The type of keyboard layout, such as "qwerty". This property is for
* informational purposes only, and does not conform to any standard.
*
* @type {String}
*/
this.type = template.type;
/**
* Map of key name to corresponding keysym, title, or key object. If only
* the keysym or title is provided, the key object will be created
* implicitly. In all cases, the name property of the key object will be
* taken from the name given in the mapping.
*
* @type {Object.<String, Number|String|Guacamole.OnScreenKeyboard.Key|Guacamole.OnScreenKeyboard.Key[]>}
*/
this.keys = template.keys;
/**
* Arbitrarily nested, arbitrarily grouped key names. The contents of the
* layout will be traversed to produce an identically-nested grouping of
* keys in the DOM tree. All strings will be transformed into their
* corresponding sets of keys, while all objects and arrays will be
* transformed into named groups and anonymous groups respectively. Any
* numbers present will be transformed into gaps of that size, scaled
* according to the same units as each key.
*
* @type {Object}
*/
this.layout = template.layout;
/**
* The width of the entire keyboard, in arbitrary units. The width of each
* key is relative to this width, as both width values are assumed to be in
* the same units. The conversion factor between these units and pixels is
* derived later via a call to resize() on the Guacamole.OnScreenKeyboard.
*
* @type {Number}
*/
this.width = template.width;
/**
* The width of each key, in arbitrary units, relative to other keys in
* this layout. The true pixel size of each key will be determined by the
* overall size of the keyboard. If not defined here, the width of each
* key will default to 1.
*
* @type {Object.<String, Number>}
*/
this.keyWidths = template.keyWidths || {};
};
/**
* Represents a single key, or a single possible behavior of a key. Each key
* on the on-screen keyboard must have at least one associated
* Guacamole.OnScreenKeyboard.Key, whether that key is explicitly defined or
* implied, and may have multiple Guacamole.OnScreenKeyboard.Key if behavior
* depends on modifier states.
*
* @constructor
* @param {Guacamole.OnScreenKeyboard.Key|Object} template
* The object whose identically-named properties will be used to initialize
* the properties of this key.
*
* @param {String} [name]
* The name to use instead of any name provided within the template, if
* any. If omitted, the name within the template will be used, assuming the
* template contains a name.
*/
Guacamole.OnScreenKeyboard.Key = function(template, name) {
/**
* The unique name identifying this key within the keyboard layout.
*
* @type {String}
*/
this.name = name || template.name;
/**
* The human-readable title that will be displayed to the user within the
* key. If not provided, this will be derived from the key name.
*
* @type {String}
*/
this.title = template.title || this.name;
/**
* The keysym to be pressed/released when this key is pressed/released. If
* not provided, this will be derived from the title if the title is a
* single character.
*
* @type {Number}
*/
this.keysym = template.keysym || (function deriveKeysym(title) {
// Do not derive keysym if title is not exactly one character
if (!title || title.length !== 1)
return null;
// For characters between U+0000 and U+00FF, the keysym is the codepoint
var charCode = title.charCodeAt(0);
if (charCode >= 0x0000 && charCode <= 0x00FF)
return charCode;
// For characters between U+0100 and U+10FFFF, the keysym is the codepoint or'd with 0x01000000
if (charCode >= 0x0100 && charCode <= 0x10FFFF)
return 0x01000000 | charCode;
// Unable to derive keysym
return null;
})(this.title);
/**
* The name of the modifier set when the key is pressed and cleared when
* this key is released, if any. The names of modifiers are distinct from
* the names of keys; both the "RightShift" and "LeftShift" keys may set
* the "shift" modifier, for example. By default, the key will affect no
* modifiers.
*
* @type {String}
*/
this.modifier = template.modifier;
/**
* An array containing the names of each modifier required for this key to
* have an effect. For example, a lowercase letter may require nothing,
* while an uppercase letter would require "shift", assuming the Shift key
* is named "shift" within the layout. By default, the key will require
* no modifiers.
*
* @type {String[]}
*/
this.requires = template.requires || [];
};