gecko/browser/components/tabview/modules/utils.jsm
2012-05-21 12:12:37 +01:00

824 lines
22 KiB
JavaScript

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
"use strict";
// **********
// Title: utils.js
let EXPORTED_SYMBOLS = ["Point", "Rect", "Range", "Subscribable", "Utils", "MRUList"];
// #########
const Ci = Components.interfaces;
const Cu = Components.utils;
Cu.import("resource://gre/modules/Services.jsm");
// ##########
// Class: Point
// A simple point.
//
// Constructor: Point
// If a is a Point, creates a copy of it. Otherwise, expects a to be x,
// and creates a Point with it along with y. If either a or y are omitted,
// 0 is used in their place.
function Point(a, y) {
if (Utils.isPoint(a)) {
this.x = a.x;
this.y = a.y;
} else {
this.x = (Utils.isNumber(a) ? a : 0);
this.y = (Utils.isNumber(y) ? y : 0);
}
};
Point.prototype = {
// ----------
// Function: toString
// Prints [Point (x,y)] for debug use
toString: function Point_toString() {
return "[Point (" + this.x + "," + this.y + ")]";
},
// ----------
// Function: distance
// Returns the distance from this point to the given <Point>.
distance: function Point_distance(point) {
var ax = this.x - point.x;
var ay = this.y - point.y;
return Math.sqrt((ax * ax) + (ay * ay));
}
};
// ##########
// Class: Rect
// A simple rectangle. Note that in addition to the left and width, it also has
// a right property; changing one affects the others appropriately. Same for the
// vertical properties.
//
// Constructor: Rect
// If a is a Rect, creates a copy of it. Otherwise, expects a to be left,
// and creates a Rect with it along with top, width, and height.
function Rect(a, top, width, height) {
// Note: perhaps 'a' should really be called 'rectOrLeft'
if (Utils.isRect(a)) {
this.left = a.left;
this.top = a.top;
this.width = a.width;
this.height = a.height;
} else {
this.left = a;
this.top = top;
this.width = width;
this.height = height;
}
};
Rect.prototype = {
// ----------
// Function: toString
// Prints [Rect (left,top,width,height)] for debug use
toString: function Rect_toString() {
return "[Rect (" + this.left + "," + this.top + "," +
this.width + "," + this.height + ")]";
},
get right() this.left + this.width,
set right(value) {
this.width = value - this.left;
},
get bottom() this.top + this.height,
set bottom(value) {
this.height = value - this.top;
},
// ----------
// Variable: xRange
// Gives you a new <Range> for the horizontal dimension.
get xRange() new Range(this.left, this.right),
// ----------
// Variable: yRange
// Gives you a new <Range> for the vertical dimension.
get yRange() new Range(this.top, this.bottom),
// ----------
// Function: intersects
// Returns true if this rectangle intersects the given <Rect>.
intersects: function Rect_intersects(rect) {
return (rect.right > this.left &&
rect.left < this.right &&
rect.bottom > this.top &&
rect.top < this.bottom);
},
// ----------
// Function: intersection
// Returns a new <Rect> with the intersection of this rectangle and the give <Rect>,
// or null if they don't intersect.
intersection: function Rect_intersection(rect) {
var box = new Rect(Math.max(rect.left, this.left), Math.max(rect.top, this.top), 0, 0);
box.right = Math.min(rect.right, this.right);
box.bottom = Math.min(rect.bottom, this.bottom);
if (box.width > 0 && box.height > 0)
return box;
return null;
},
// ----------
// Function: contains
// Returns a boolean denoting if the <Rect> or <Point> is contained inside
// this rectangle.
//
// Parameters
// - A <Rect> or a <Point>
contains: function Rect_contains(a) {
if (Utils.isPoint(a))
return (a.x > this.left &&
a.x < this.right &&
a.y > this.top &&
a.y < this.bottom);
return (a.left >= this.left &&
a.right <= this.right &&
a.top >= this.top &&
a.bottom <= this.bottom);
},
// ----------
// Function: center
// Returns a new <Point> with the center location of this rectangle.
center: function Rect_center() {
return new Point(this.left + (this.width / 2), this.top + (this.height / 2));
},
// ----------
// Function: size
// Returns a new <Point> with the dimensions of this rectangle.
size: function Rect_size() {
return new Point(this.width, this.height);
},
// ----------
// Function: position
// Returns a new <Point> with the top left of this rectangle.
position: function Rect_position() {
return new Point(this.left, this.top);
},
// ----------
// Function: area
// Returns the area of this rectangle.
area: function Rect_area() {
return this.width * this.height;
},
// ----------
// Function: inset
// Makes the rect smaller (if the arguments are positive) as if a margin is added all around
// the initial rect, with the margin widths (symmetric) being specified by the arguments.
//
// Paramaters
// - A <Point> or two arguments: x and y
inset: function Rect_inset(a, b) {
if (Utils.isPoint(a)) {
b = a.y;
a = a.x;
}
this.left += a;
this.width -= a * 2;
this.top += b;
this.height -= b * 2;
},
// ----------
// Function: offset
// Moves (translates) the rect by the given vector.
//
// Paramaters
// - A <Point> or two arguments: x and y
offset: function Rect_offset(a, b) {
if (Utils.isPoint(a)) {
this.left += a.x;
this.top += a.y;
} else {
this.left += a;
this.top += b;
}
},
// ----------
// Function: equals
// Returns true if this rectangle is identical to the given <Rect>.
equals: function Rect_equals(rect) {
return (rect.left == this.left &&
rect.top == this.top &&
rect.width == this.width &&
rect.height == this.height);
},
// ----------
// Function: union
// Returns a new <Rect> with the union of this rectangle and the given <Rect>.
union: function Rect_union(a) {
var newLeft = Math.min(a.left, this.left);
var newTop = Math.min(a.top, this.top);
var newWidth = Math.max(a.right, this.right) - newLeft;
var newHeight = Math.max(a.bottom, this.bottom) - newTop;
var newRect = new Rect(newLeft, newTop, newWidth, newHeight);
return newRect;
},
// ----------
// Function: copy
// Copies the values of the given <Rect> into this rectangle.
copy: function Rect_copy(a) {
this.left = a.left;
this.top = a.top;
this.width = a.width;
this.height = a.height;
}
};
// ##########
// Class: Range
// A physical interval, with a min and max.
//
// Constructor: Range
// Creates a Range with the given min and max
function Range(min, max) {
if (Utils.isRange(min) && !max) { // if the one variable given is a range, copy it.
this.min = min.min;
this.max = min.max;
} else {
this.min = min || 0;
this.max = max || 0;
}
};
Range.prototype = {
// ----------
// Function: toString
// Prints [Range (min,max)] for debug use
toString: function Range_toString() {
return "[Range (" + this.min + "," + this.max + ")]";
},
// Variable: extent
// Equivalent to max-min
get extent() {
return (this.max - this.min);
},
set extent(extent) {
this.max = extent - this.min;
},
// ----------
// Function: contains
// Whether the <Range> contains the given <Range> or value or not.
//
// Parameters
// - a number or <Range>
contains: function Range_contains(value) {
if (Utils.isNumber(value))
return value >= this.min && value <= this.max;
if (Utils.isRange(value))
return value.min >= this.min && value.max <= this.max;
return false;
},
// ----------
// Function: overlaps
// Whether the <Range> overlaps with the given <Range> value or not.
//
// Parameters
// - a number or <Range>
overlaps: function Range_overlaps(value) {
if (Utils.isNumber(value))
return this.contains(value);
if (Utils.isRange(value))
return !(value.max < this.min || this.max < value.min);
return false;
},
// ----------
// Function: proportion
// Maps the given value to the range [0,1], so that it returns 0 if the value is <= the min,
// returns 1 if the value >= the max, and returns an interpolated "proportion" in (min, max).
//
// Parameters
// - a number
// - (bool) smooth? If true, a smooth tanh-based function will be used instead of the linear.
proportion: function Range_proportion(value, smooth) {
if (value <= this.min)
return 0;
if (this.max <= value)
return 1;
var proportion = (value - this.min) / this.extent;
if (smooth) {
// The ease function ".5+.5*Math.tanh(4*x-2)" is a pretty
// little graph. It goes from near 0 at x=0 to near 1 at x=1
// smoothly and beautifully.
// http://www.wolframalpha.com/input/?i=.5+%2B+.5+*+tanh%28%284+*+x%29+-+2%29
let tanh = function tanh(x) {
var e = Math.exp(x);
return (e - 1/e) / (e + 1/e);
};
return .5 - .5 * tanh(2 - 4 * proportion);
}
return proportion;
},
// ----------
// Function: scale
// Takes the given value in [0,1] and maps it to the associated value on the Range.
//
// Parameters
// - a number in [0,1]
scale: function Range_scale(value) {
if (value > 1)
value = 1;
if (value < 0)
value = 0;
return this.min + this.extent * value;
}
};
// ##########
// Class: Subscribable
// A mix-in for allowing objects to collect subscribers for custom events.
function Subscribable() {
this.subscribers = null;
};
Subscribable.prototype = {
// ----------
// Function: addSubscriber
// The given callback will be called when the Subscribable fires the given event.
addSubscriber: function Subscribable_addSubscriber(eventName, callback) {
try {
Utils.assertThrow(typeof callback == "function", "callback must be a function");
Utils.assertThrow(eventName && typeof eventName == "string",
"eventName must be a non-empty string");
} catch(e) {
Utils.log(e);
return;
}
if (!this.subscribers)
this.subscribers = {};
if (!this.subscribers[eventName])
this.subscribers[eventName] = [];
let subscribers = this.subscribers[eventName];
if (subscribers.indexOf(callback) == -1)
subscribers.push(callback);
},
// ----------
// Function: removeSubscriber
// Removes the subscriber associated with the event for the given callback.
removeSubscriber: function Subscribable_removeSubscriber(eventName, callback) {
try {
Utils.assertThrow(typeof callback == "function", "callback must be a function");
Utils.assertThrow(eventName && typeof eventName == "string",
"eventName must be a non-empty string");
} catch(e) {
Utils.log(e);
return;
}
if (!this.subscribers || !this.subscribers[eventName])
return;
let subscribers = this.subscribers[eventName];
let index = subscribers.indexOf(callback);
if (index > -1)
subscribers.splice(index, 1);
},
// ----------
// Function: _sendToSubscribers
// Internal routine. Used by the Subscribable to fire events.
_sendToSubscribers: function Subscribable__sendToSubscribers(eventName, eventInfo) {
try {
Utils.assertThrow(eventName && typeof eventName == "string",
"eventName must be a non-empty string");
} catch(e) {
Utils.log(e);
return;
}
if (!this.subscribers || !this.subscribers[eventName])
return;
let subsCopy = this.subscribers[eventName].concat();
subsCopy.forEach(function (callback) {
try {
callback(this, eventInfo);
} catch(e) {
Utils.log(e);
}
}, this);
}
};
// ##########
// Class: Utils
// Singelton with common utility functions.
let Utils = {
// ----------
// Function: toString
// Prints [Utils] for debug use
toString: function Utils_toString() {
return "[Utils]";
},
// ___ Logging
useConsole: true, // as opposed to dump
showTime: false,
// ----------
// Function: log
// Prints the given arguments to the JavaScript error console as a message.
// Pass as many arguments as you want, it'll print them all.
log: function Utils_log() {
var text = this.expandArgumentsForLog(arguments);
var prefix = this.showTime ? Date.now() + ': ' : '';
if (this.useConsole)
Services.console.logStringMessage(prefix + text);
else
dump(prefix + text + '\n');
},
// ----------
// Function: error
// Prints the given arguments to the JavaScript error console as an error.
// Pass as many arguments as you want, it'll print them all.
error: function Utils_error() {
var text = this.expandArgumentsForLog(arguments);
var prefix = this.showTime ? Date.now() + ': ' : '';
if (this.useConsole)
Cu.reportError(prefix + "tabview error: " + text);
else
dump(prefix + "TABVIEW ERROR: " + text + '\n');
},
// ----------
// Function: trace
// Prints the given arguments to the JavaScript error console as a message,
// along with a full stack trace.
// Pass as many arguments as you want, it'll print them all.
trace: function Utils_trace() {
var text = this.expandArgumentsForLog(arguments);
// cut off the first line of the stack trace, because that's just this function.
let stack = Error().stack.split("\n").slice(1);
// if the caller was assert, cut out the line for the assert function as well.
if (stack[0].indexOf("Utils_assert(") == 0)
stack.splice(0, 1);
this.log('trace: ' + text + '\n' + stack.join("\n"));
},
// ----------
// Function: assert
// Prints a stack trace along with label (as a console message) if condition is false.
assert: function Utils_assert(condition, label) {
if (!condition) {
let text;
if (typeof label != 'string')
text = 'badly formed assert';
else
text = "tabview assert: " + label;
this.trace(text);
}
},
// ----------
// Function: assertThrow
// Throws label as an exception if condition is false.
assertThrow: function Utils_assertThrow(condition, label) {
if (!condition) {
let text;
if (typeof label != 'string')
text = 'badly formed assert';
else
text = "tabview assert: " + label;
// cut off the first line of the stack trace, because that's just this function.
let stack = Error().stack.split("\n").slice(1);
throw text + "\n" + stack.join("\n");
}
},
// ----------
// Function: expandObject
// Prints the given object to a string, including all of its properties.
expandObject: function Utils_expandObject(obj) {
var s = obj + ' = {';
for (let prop in obj) {
let value;
try {
value = obj[prop];
} catch(e) {
value = '[!!error retrieving property]';
}
s += prop + ': ';
if (typeof value == 'string')
s += '\'' + value + '\'';
else if (typeof value == 'function')
s += 'function';
else
s += value;
s += ', ';
}
return s + '}';
},
// ----------
// Function: expandArgumentsForLog
// Expands all of the given args (an array) into a single string.
expandArgumentsForLog: function Utils_expandArgumentsForLog(args) {
var that = this;
return Array.map(args, function(arg) {
return typeof arg == 'object' ? that.expandObject(arg) : arg;
}).join('; ');
},
// ___ Misc
// ----------
// Function: isLeftClick
// Given a DOM mouse event, returns true if it was for the left mouse button.
isLeftClick: function Utils_isLeftClick(event) {
return event.button == 0;
},
// ----------
// Function: isMiddleClick
// Given a DOM mouse event, returns true if it was for the middle mouse button.
isMiddleClick: function Utils_isMiddleClick(event) {
return event.button == 1;
},
// ----------
// Function: isRightClick
// Given a DOM mouse event, returns true if it was for the right mouse button.
isRightClick: function Utils_isRightClick(event) {
return event.button == 2;
},
// ----------
// Function: isDOMElement
// Returns true if the given object is a DOM element.
isDOMElement: function Utils_isDOMElement(object) {
return object instanceof Ci.nsIDOMElement;
},
// ----------
// Function: isValidXULTab
// A xulTab is valid if it has not been closed,
// and it has not been removed from the DOM
// Returns true if the tab is valid.
isValidXULTab: function Utils_isValidXULTab(xulTab) {
return !xulTab.closing && xulTab.parentNode;
},
// ----------
// Function: isNumber
// Returns true if the argument is a valid number.
isNumber: function Utils_isNumber(n) {
return typeof n == 'number' && !isNaN(n);
},
// ----------
// Function: isRect
// Returns true if the given object (r) looks like a <Rect>.
isRect: function Utils_isRect(r) {
return (r &&
this.isNumber(r.left) &&
this.isNumber(r.top) &&
this.isNumber(r.width) &&
this.isNumber(r.height));
},
// ----------
// Function: isRange
// Returns true if the given object (r) looks like a <Range>.
isRange: function Utils_isRange(r) {
return (r &&
this.isNumber(r.min) &&
this.isNumber(r.max));
},
// ----------
// Function: isPoint
// Returns true if the given object (p) looks like a <Point>.
isPoint: function Utils_isPoint(p) {
return (p && this.isNumber(p.x) && this.isNumber(p.y));
},
// ----------
// Function: isPlainObject
// Check to see if an object is a plain object (created using "{}" or "new Object").
isPlainObject: function Utils_isPlainObject(obj) {
// Must be an Object.
// Make sure that DOM nodes and window objects don't pass through, as well
if (!obj || Object.prototype.toString.call(obj) !== "[object Object]" ||
obj.nodeType || obj.setInterval) {
return false;
}
// Not own constructor property must be Object
const hasOwnProperty = Object.prototype.hasOwnProperty;
if (obj.constructor &&
!hasOwnProperty.call(obj, "constructor") &&
!hasOwnProperty.call(obj.constructor.prototype, "isPrototypeOf")) {
return false;
}
// Own properties are enumerated firstly, so to speed up,
// if last one is own, then all properties are own.
var key;
for (key in obj) {}
return key === undefined || hasOwnProperty.call(obj, key);
},
// ----------
// Function: isEmptyObject
// Returns true if the given object has no members.
isEmptyObject: function Utils_isEmptyObject(obj) {
for (let name in obj)
return false;
return true;
},
// ----------
// Function: copy
// Returns a copy of the argument. Note that this is a shallow copy; if the argument
// has properties that are themselves objects, those properties will be copied by reference.
copy: function Utils_copy(value) {
if (value && typeof value == 'object') {
if (Array.isArray(value))
return this.extend([], value);
return this.extend({}, value);
}
return value;
},
// ----------
// Function: merge
// Merge two array-like objects into the first and return it.
merge: function Utils_merge(first, second) {
Array.forEach(second, function(el) Array.push(first, el));
return first;
},
// ----------
// Function: extend
// Pass several objects in and it will combine them all into the first object and return it.
extend: function Utils_extend() {
// copy reference to target object
let target = arguments[0] || {};
// Deep copy is not supported
if (typeof target === "boolean") {
this.assert(false, "The first argument of extend cannot be a boolean." +
"Deep copy is not supported.");
return target;
}
// Back when this was in iQ + iQ.fn, so you could extend iQ objects with it.
// This is no longer supported.
let length = arguments.length;
if (length === 1) {
this.assert(false, "Extending the iQ prototype using extend is not supported.");
return target;
}
// Handle case when target is a string or something
if (typeof target != "object" && typeof target != "function") {
target = {};
}
for (let i = 1; i < length; i++) {
// Only deal with non-null/undefined values
let options = arguments[i];
if (options != null) {
// Extend the base object
for (let name in options) {
let copy = options[name];
// Prevent never-ending loop
if (target === copy)
continue;
if (copy !== undefined)
target[name] = copy;
}
}
}
// Return the modified object
return target;
},
// ----------
// Function: attempt
// Tries to execute a number of functions. Returns immediately the return
// value of the first non-failed function without executing successive
// functions, or null.
attempt: function Utils_attempt() {
let args = arguments;
for (let i = 0; i < args.length; i++) {
try {
return args[i]();
} catch (e) {}
}
return null;
}
};
// ##########
// Class: MRUList
// A most recently used list.
//
// Constructor: MRUList
// If a is an array of entries, creates a copy of it.
function MRUList(a) {
if (Array.isArray(a))
this._list = a.concat();
else
this._list = [];
};
MRUList.prototype = {
// ----------
// Function: toString
// Prints [List (entry1, entry2, ...)] for debug use
toString: function MRUList_toString() {
return "[List (" + this._list.join(", ") + ")]";
},
// ----------
// Function: update
// Updates/inserts the given entry as the most recently used one in the list.
update: function MRUList_update(entry) {
this.remove(entry);
this._list.unshift(entry);
},
// ----------
// Function: remove
// Removes the given entry from the list.
remove: function MRUList_remove(entry) {
let index = this._list.indexOf(entry);
if (index > -1)
this._list.splice(index, 1);
},
// ----------
// Function: peek
// Returns the most recently used entry. If a filter exists, gets the most
// recently used entry which matches the filter.
peek: function MRUList_peek(filter) {
let match = null;
if (filter && typeof filter == "function")
this._list.some(function MRUList_peek_getEntry(entry) {
if (filter(entry)) {
match = entry
return true;
}
return false;
});
else
match = this._list.length > 0 ? this._list[0] : null;
return match;
},
};