src/shared/js/cr.js - platform/external/chromium-trace - Git at Google

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 /**
  * The global object.
  * @type {!Object}
  * @const
  */
 var global = this;

 /** Platform, package, object property, and Event support. **/
 this.cr = (function() {
   'use strict';

   /**
    * Tags the html element with an attribute that allows touch-specific css
    * rules.
    * TODO(rbyers): make Chrome always touch-optimized. http://crbug.com/105380
    */
   function enableTouchOptimizedCss() {
     if (cr.isTouchOptimized)
       doc.documentElement.setAttribute('touch-optimized', '');
   }

   /**
    * Builds an object structure for the provided namespace path,
    * ensuring that names that already exist are not overwritten. For
    * example:
    * "a.b.c" -> a = {};a.b={};a.b.c={};
    * @param {string} name Name of the object that this file defines.
    * @param {*=} opt_object The object to expose at the end of the path.
    * @param {Object=} opt_objectToExportTo The object to add the path to;
    *     default is {@code global}.
    * @private
    */
   function exportPath(name, opt_object, opt_objectToExportTo) {
     var parts = name.split('.');
     var cur = opt_objectToExportTo || global;

     for (var part; parts.length && (part = parts.shift());) {
       if (!parts.length && opt_object !== undefined) {
         // last part and we have an object; use it
         cur[part] = opt_object;
       } else if (part in cur) {
         cur = cur[part];
       } else {
         cur = cur[part] = {};
       }
     }
     return cur;
   };

   /**
    * Fires a property change event on the target.
    * @param {EventTarget} target The target to dispatch the event on.
    * @param {string} propertyName The name of the property that changed.
    * @param {*} newValue The new value for the property.
    * @param {*} oldValue The old value for the property.
    */
   function dispatchPropertyChange(target, propertyName, newValue, oldValue) {
     var e = new cr.Event(propertyName + 'Change');
     e.propertyName = propertyName;
     e.newValue = newValue;
     e.oldValue = oldValue;
     target.dispatchEvent(e);
   }

   /**
    * Converts a camelCase javascript property name to a hyphenated-lower-case
    * attribute name.
    * @param {string} jsName The javascript camelCase property name.
    * @return {string} The equivalent hyphenated-lower-case attribute name.
    */
   function getAttributeName(jsName) {
     return jsName.replace(/([A-Z])/g, '-$1').toLowerCase();
   }

   /**
    * The kind of property to define in {@code defineProperty}.
    * @enum {number}
    * @const
    */
   var PropertyKind = {
     /**
      * Plain old JS property where the backing data is stored as a "private"
      * field on the object.
      */
     JS: 'js',

     /**
      * The property backing data is stored as an attribute on an element.
      */
     ATTR: 'attr',

     /**
      * The property backing data is stored as an attribute on an element. If the
      * element has the attribute then the value is true.
      */
     BOOL_ATTR: 'boolAttr'
   };

   /**
    * Helper function for defineProperty that returns the getter to use for the
    * property.
    * @param {string} name The name of the property.
    * @param {cr.PropertyKind} kind The kind of the property.
    * @return {function():*} The getter for the property.
    */
   function getGetter(name, kind) {
     switch (kind) {
       case PropertyKind.JS:
         var privateName = name + '_';
         return function() {
           return this[privateName];
         };
       case PropertyKind.ATTR:
         var attributeName = getAttributeName(name);
         return function() {
           return this.getAttribute(attributeName);
         };
       case PropertyKind.BOOL_ATTR:
         var attributeName = getAttributeName(name);
         return function() {
           return this.hasAttribute(attributeName);
         };
     }
   }

   /**
    * Helper function for defineProperty that returns the setter of the right
    * kind.
    * @param {string} name The name of the property we are defining the setter
    *     for.
    * @param {cr.PropertyKind} kind The kind of property we are getting the
    *     setter for.
    * @param {function(*):void} opt_setHook A function to run after the property
    *     is set, but before the propertyChange event is fired.
    * @return {function(*):void} The function to use as a setter.
    */
   function getSetter(name, kind, opt_setHook) {
     switch (kind) {
       case PropertyKind.JS:
         var privateName = name + '_';
         return function(value) {
           var oldValue = this[privateName];
           if (value !== oldValue) {
             this[privateName] = value;
             if (opt_setHook)
               opt_setHook.call(this, value, oldValue);
             dispatchPropertyChange(this, name, value, oldValue);
           }
         };

       case PropertyKind.ATTR:
         var attributeName = getAttributeName(name);
         return function(value) {
           var oldValue = this[attributeName];
           if (value !== oldValue) {
             if (value == undefined)
               this.removeAttribute(attributeName);
             else
               this.setAttribute(attributeName, value);
             if (opt_setHook)
               opt_setHook.call(this, value, oldValue);
             dispatchPropertyChange(this, name, value, oldValue);
           }
         };

       case PropertyKind.BOOL_ATTR:
         var attributeName = getAttributeName(name);
         return function(value) {
           var oldValue = this[attributeName];
           if (value !== oldValue) {
             if (value)
               this.setAttribute(attributeName, name);
             else
               this.removeAttribute(attributeName);
             if (opt_setHook)
               opt_setHook.call(this, value, oldValue);
             dispatchPropertyChange(this, name, value, oldValue);
           }
         };
     }
   }

   /**
    * Defines a property on an object. When the setter changes the value a
    * property change event with the type {@code name + 'Change'} is fired.
    * @param {!Object} obj The object to define the property for.
    * @param {string} name The name of the property.
    * @param {cr.PropertyKind=} opt_kind What kind of underlying storage to use.
    * @param {function(*):void} opt_setHook A function to run after the
    *     property is set, but before the propertyChange event is fired.
    */
   function defineProperty(obj, name, opt_kind, opt_setHook) {
     if (typeof obj == 'function')
       obj = obj.prototype;

     var kind = opt_kind || PropertyKind.JS;

     if (!obj.__lookupGetter__(name))
       obj.__defineGetter__(name, getGetter(name, kind));

     if (!obj.__lookupSetter__(name))
       obj.__defineSetter__(name, getSetter(name, kind, opt_setHook));
   }

   /**
    * Counter for use with createUid
    */
   var uidCounter = 1;

   /**
    * @return {number} A new unique ID.
    */
   function createUid() {
     return uidCounter++;
   }

   /**
    * Returns a unique ID for the item. This mutates the item so it needs to be
    * an object
    * @param {!Object} item The item to get the unique ID for.
    * @return {number} The unique ID for the item.
    */
   function getUid(item) {
     if (item.hasOwnProperty('uid'))
       return item.uid;
     return item.uid = createUid();
   }

   /**
    * Dispatches a simple event on an event target.
    * @param {!EventTarget} target The event target to dispatch the event on.
    * @param {string} type The type of the event.
    * @param {boolean=} opt_bubbles Whether the event bubbles or not.
    * @param {boolean=} opt_cancelable Whether the default action of the event
    *     can be prevented.
    * @return {boolean} If any of the listeners called {@code preventDefault}
    *     during the dispatch this will return false.
    */
   function dispatchSimpleEvent(target, type, opt_bubbles, opt_cancelable) {
     var e = new cr.Event(type, opt_bubbles, opt_cancelable);
     return target.dispatchEvent(e);
   }

   /**
    * Calls |fun| and adds all the fields of the returned object to the object
    * named by |name|. For example, cr.define('cr.ui', function() {
    *   function List() {
    *     ...
    *   }
    *   function ListItem() {
    *     ...
    *   }
    *   return {
    *     List: List,
    *     ListItem: ListItem,
    *   };
    * });
    * defines the functions cr.ui.List and cr.ui.ListItem.
    * @param {string} name The name of the object that we are adding fields to.
    * @param {!Function} fun The function that will return an object containing
    *     the names and values of the new fields.
    */
   function define(name, fun) {
     var obj = exportPath(name);
     var exports = fun();
     for (var propertyName in exports) {
       // Maybe we should check the prototype chain here? The current usage
       // pattern is always using an object literal so we only care about own
       // properties.
       var propertyDescriptor = Object.getOwnPropertyDescriptor(exports,
                                                                propertyName);
       if (propertyDescriptor)
         Object.defineProperty(obj, propertyName, propertyDescriptor);
     }
   }

   /**
    * Adds a {@code getInstance} static method that always return the same
    * instance object.
    * @param {!Function} ctor The constructor for the class to add the static
    *     method to.
    */
   function addSingletonGetter(ctor) {
     ctor.getInstance = function() {
       return ctor.instance_ || (ctor.instance_ = new ctor());
     };
   }

   /**
    * Creates a new event to be used with cr.EventTarget or DOM EventTarget
    * objects.
    * @param {string} type The name of the event.
    * @param {boolean=} opt_bubbles Whether the event bubbles.
    *     Default is false.
    * @param {boolean=} opt_preventable Whether the default action of the event
    *     can be prevented.
    * @constructor
    * @extends {Event}
    */
   function Event(type, opt_bubbles, opt_preventable) {
     var e = cr.doc.createEvent('Event');
     e.initEvent(type, !!opt_bubbles, !!opt_preventable);
     e.__proto__ = global.Event.prototype;
     return e;
   };

   /**
    * Initialization which must be deferred until run-time.
    */
   function initialize() {
     // If 'document' isn't defined, then we must be being pre-compiled,
     // so set a trap so that we're initialized on first access at run-time.
     if (!global.document) {
       var originalCr = cr;

       Object.defineProperty(global, 'cr', {
         get: function() {
           Object.defineProperty(global, 'cr', {value: originalCr});
           originalCr.initialize();
           return originalCr;
         },
         configurable: true
       });

       return;
     }

     Event.prototype = {__proto__: global.Event.prototype};

     /**
      * Whether we are using a Mac or not.
      */
     cr.isMac = /Mac/.test(navigator.platform);

     /**
      * Whether this is on the Windows platform or not.
      */
     cr.isWindows = /Win/.test(navigator.platform);

     /**
      * Whether this is on chromeOS or not.
      */
     cr.isChromeOS = /CrOS/.test(navigator.userAgent);

     /**
      * Whether this is on vanilla Linux (not chromeOS).
      */
     cr.isLinux = /Linux/.test(navigator.userAgent);

     /**
      * Whether this uses GTK or not.
      */
     cr.isGTK = /GTK/.test(chrome.toolkit);

     /**
      * Whether this uses the views toolkit or not.
      */
     cr.isViews = /views/.test(chrome.toolkit);

     /**
      * Whether this window is optimized for touch-based input.
      */
     cr.isTouchOptimized = !!chrome.touchOptimized;

     enableTouchOptimizedCss();
   }

   return {
     addSingletonGetter: addSingletonGetter,
     createUid: createUid,
     define: define,
     defineProperty: defineProperty,
     dispatchPropertyChange: dispatchPropertyChange,
     dispatchSimpleEvent: dispatchSimpleEvent,
     Event: Event,
     getUid: getUid,
     initialize: initialize,
     PropertyKind: PropertyKind,

     /**
      * The document that we are currently using.
      * @type {!Document}
      */
     get doc() {
       return document;
     }
   };
 })();


 /**
  * TODO(kgr): Move this to another file which is to be loaded last.
  * This will be done as part of future work to make this code pre-compilable.
  */
 cr.initialize();
	// Copyright (c) 2012 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	/**
	* The global object.
	* @type {!Object}
	* @const
	*/
	var global = this;

	/ Platform, package, object property, and Event support. /
	this.cr = (function() {
	'use strict';

	/**
	* Tags the html element with an attribute that allows touch-specific css
	* rules.
	* TODO(rbyers): make Chrome always touch-optimized. http://crbug.com/105380
	*/
	function enableTouchOptimizedCss() {
	if (cr.isTouchOptimized)
	doc.documentElement.setAttribute('touch-optimized', '');
	}

	/**
	* Builds an object structure for the provided namespace path,
	* ensuring that names that already exist are not overwritten. For
	* example:
	* "a.b.c" -> a = {};a.b={};a.b.c={};
	* @param {string} name Name of the object that this file defines.
	* @param {*=} opt_object The object to expose at the end of the path.
	* @param {Object=} opt_objectToExportTo The object to add the path to;
	* default is {@code global}.
	* @private
	*/
	function exportPath(name, opt_object, opt_objectToExportTo) {
	var parts = name.split('.');
	var cur = opt_objectToExportTo \|\| global;

	for (var part; parts.length && (part = parts.shift());) {
	if (!parts.length && opt_object !== undefined) {
	// last part and we have an object; use it
	cur[part] = opt_object;
	} else if (part in cur) {
	cur = cur[part];
	} else {
	cur = cur[part] = {};
	}
	}
	return cur;
	};

	/**
	* Fires a property change event on the target.
	* @param {EventTarget} target The target to dispatch the event on.
	* @param {string} propertyName The name of the property that changed.
	* @param {*} newValue The new value for the property.
	* @param {*} oldValue The old value for the property.
	*/
	function dispatchPropertyChange(target, propertyName, newValue, oldValue) {
	var e = new cr.Event(propertyName + 'Change');
	e.propertyName = propertyName;
	e.newValue = newValue;
	e.oldValue = oldValue;
	target.dispatchEvent(e);
	}

	/**
	* Converts a camelCase javascript property name to a hyphenated-lower-case
	* attribute name.
	* @param {string} jsName The javascript camelCase property name.
	* @return {string} The equivalent hyphenated-lower-case attribute name.
	*/
	function getAttributeName(jsName) {
	return jsName.replace(/([A-Z])/g, '-$1').toLowerCase();
	}

	/**
	* The kind of property to define in {@code defineProperty}.
	* @enum {number}
	* @const
	*/
	var PropertyKind = {
	/**
	* Plain old JS property where the backing data is stored as a "private"
	* field on the object.
	*/
	JS: 'js',

	/**
	* The property backing data is stored as an attribute on an element.
	*/
	ATTR: 'attr',

	/**
	* The property backing data is stored as an attribute on an element. If the
	* element has the attribute then the value is true.
	*/
	BOOL_ATTR: 'boolAttr'
	};

	/**
	* Helper function for defineProperty that returns the getter to use for the
	* property.
	* @param {string} name The name of the property.
	* @param {cr.PropertyKind} kind The kind of the property.
	* @return {function():*} The getter for the property.
	*/
	function getGetter(name, kind) {
	switch (kind) {
	case PropertyKind.JS:
	var privateName = name + '_';
	return function() {
	return this[privateName];
	};
	case PropertyKind.ATTR:
	var attributeName = getAttributeName(name);
	return function() {
	return this.getAttribute(attributeName);
	};
	case PropertyKind.BOOL_ATTR:
	var attributeName = getAttributeName(name);
	return function() {
	return this.hasAttribute(attributeName);
	};
	}
	}

	/**
	* Helper function for defineProperty that returns the setter of the right
	* kind.
	* @param {string} name The name of the property we are defining the setter
	* for.
	* @param {cr.PropertyKind} kind The kind of property we are getting the
	* setter for.
	* @param {function(*):void} opt_setHook A function to run after the property
	* is set, but before the propertyChange event is fired.
	* @return {function(*):void} The function to use as a setter.
	*/
	function getSetter(name, kind, opt_setHook) {
	switch (kind) {
	case PropertyKind.JS:
	var privateName = name + '_';
	return function(value) {
	var oldValue = this[privateName];
	if (value !== oldValue) {
	this[privateName] = value;
	if (opt_setHook)
	opt_setHook.call(this, value, oldValue);
	dispatchPropertyChange(this, name, value, oldValue);
	}
	};

	case PropertyKind.ATTR:
	var attributeName = getAttributeName(name);
	return function(value) {
	var oldValue = this[attributeName];
	if (value !== oldValue) {
	if (value == undefined)
	this.removeAttribute(attributeName);
	else
	this.setAttribute(attributeName, value);
	if (opt_setHook)
	opt_setHook.call(this, value, oldValue);
	dispatchPropertyChange(this, name, value, oldValue);
	}
	};

	case PropertyKind.BOOL_ATTR:
	var attributeName = getAttributeName(name);
	return function(value) {
	var oldValue = this[attributeName];
	if (value !== oldValue) {
	if (value)
	this.setAttribute(attributeName, name);
	else
	this.removeAttribute(attributeName);
	if (opt_setHook)
	opt_setHook.call(this, value, oldValue);
	dispatchPropertyChange(this, name, value, oldValue);
	}
	};
	}
	}

	/**
	* Defines a property on an object. When the setter changes the value a
	* property change event with the type {@code name + 'Change'} is fired.
	* @param {!Object} obj The object to define the property for.
	* @param {string} name The name of the property.
	* @param {cr.PropertyKind=} opt_kind What kind of underlying storage to use.
	* @param {function(*):void} opt_setHook A function to run after the
	* property is set, but before the propertyChange event is fired.
	*/
	function defineProperty(obj, name, opt_kind, opt_setHook) {
	if (typeof obj == 'function')
	obj = obj.prototype;

	var kind = opt_kind \|\| PropertyKind.JS;

	if (!obj.__lookupGetter__(name))
	obj.__defineGetter__(name, getGetter(name, kind));

	if (!obj.__lookupSetter__(name))
	obj.__defineSetter__(name, getSetter(name, kind, opt_setHook));
	}

	/**
	* Counter for use with createUid
	*/
	var uidCounter = 1;

	/**
	* @return {number} A new unique ID.
	*/
	function createUid() {
	return uidCounter++;
	}

	/**
	* Returns a unique ID for the item. This mutates the item so it needs to be
	* an object
	* @param {!Object} item The item to get the unique ID for.
	* @return {number} The unique ID for the item.
	*/
	function getUid(item) {
	if (item.hasOwnProperty('uid'))
	return item.uid;
	return item.uid = createUid();
	}

	/**
	* Dispatches a simple event on an event target.
	* @param {!EventTarget} target The event target to dispatch the event on.
	* @param {string} type The type of the event.
	* @param {boolean=} opt_bubbles Whether the event bubbles or not.
	* @param {boolean=} opt_cancelable Whether the default action of the event
	* can be prevented.
	* @return {boolean} If any of the listeners called {@code preventDefault}
	* during the dispatch this will return false.
	*/
	function dispatchSimpleEvent(target, type, opt_bubbles, opt_cancelable) {
	var e = new cr.Event(type, opt_bubbles, opt_cancelable);
	return target.dispatchEvent(e);
	}

	/**
	* Calls \|fun\| and adds all the fields of the returned object to the object
	* named by \|name\|. For example, cr.define('cr.ui', function() {
	* function List() {
	* ...
	* }
	* function ListItem() {
	* ...
	* }
	* return {
	* List: List,
	* ListItem: ListItem,
	* };
	* });
	* defines the functions cr.ui.List and cr.ui.ListItem.
	* @param {string} name The name of the object that we are adding fields to.
	* @param {!Function} fun The function that will return an object containing
	* the names and values of the new fields.
	*/
	function define(name, fun) {
	var obj = exportPath(name);
	var exports = fun();
	for (var propertyName in exports) {
	// Maybe we should check the prototype chain here? The current usage
	// pattern is always using an object literal so we only care about own
	// properties.
	var propertyDescriptor = Object.getOwnPropertyDescriptor(exports,
	propertyName);
	if (propertyDescriptor)
	Object.defineProperty(obj, propertyName, propertyDescriptor);
	}
	}

	/**
	* Adds a {@code getInstance} static method that always return the same
	* instance object.
	* @param {!Function} ctor The constructor for the class to add the static
	* method to.
	*/
	function addSingletonGetter(ctor) {
	ctor.getInstance = function() {
	return ctor.instance_ \|\| (ctor.instance_ = new ctor());
	};
	}

	/**
	* Creates a new event to be used with cr.EventTarget or DOM EventTarget
	* objects.
	* @param {string} type The name of the event.
	* @param {boolean=} opt_bubbles Whether the event bubbles.
	* Default is false.
	* @param {boolean=} opt_preventable Whether the default action of the event
	* can be prevented.
	* @constructor
	* @extends {Event}
	*/
	function Event(type, opt_bubbles, opt_preventable) {
	var e = cr.doc.createEvent('Event');
	e.initEvent(type, !!opt_bubbles, !!opt_preventable);
	e.__proto__ = global.Event.prototype;
	return e;
	};

	/**
	* Initialization which must be deferred until run-time.
	*/
	function initialize() {
	// If 'document' isn't defined, then we must be being pre-compiled,
	// so set a trap so that we're initialized on first access at run-time.
	if (!global.document) {
	var originalCr = cr;

	Object.defineProperty(global, 'cr', {
	get: function() {
	Object.defineProperty(global, 'cr', {value: originalCr});
	originalCr.initialize();
	return originalCr;
	},
	configurable: true
	});

	return;
	}

	Event.prototype = {__proto__: global.Event.prototype};

	/**
	* Whether we are using a Mac or not.
	*/
	cr.isMac = /Mac/.test(navigator.platform);

	/**
	* Whether this is on the Windows platform or not.
	*/
	cr.isWindows = /Win/.test(navigator.platform);

	/**
	* Whether this is on chromeOS or not.
	*/
	cr.isChromeOS = /CrOS/.test(navigator.userAgent);

	/**
	* Whether this is on vanilla Linux (not chromeOS).
	*/
	cr.isLinux = /Linux/.test(navigator.userAgent);

	/**
	* Whether this uses GTK or not.
	*/
	cr.isGTK = /GTK/.test(chrome.toolkit);

	/**
	* Whether this uses the views toolkit or not.
	*/
	cr.isViews = /views/.test(chrome.toolkit);

	/**
	* Whether this window is optimized for touch-based input.
	*/
	cr.isTouchOptimized = !!chrome.touchOptimized;

	enableTouchOptimizedCss();
	}

	return {
	addSingletonGetter: addSingletonGetter,
	createUid: createUid,
	define: define,
	defineProperty: defineProperty,
	dispatchPropertyChange: dispatchPropertyChange,
	dispatchSimpleEvent: dispatchSimpleEvent,
	Event: Event,
	getUid: getUid,
	initialize: initialize,
	PropertyKind: PropertyKind,

	/**
	* The document that we are currently using.
	* @type {!Document}
	*/
	get doc() {
	return document;
	}
	};
	})();


	/**
	* TODO(kgr): Move this to another file which is to be loaded last.
	* This will be done as part of future work to make this code pre-compilable.
	*/
	cr.initialize();