plupload/src/moxie/build/utils.js

Plupload is a JavaScript API for dealing with file uploads it supports features like multiple file selection, file type filtering, request chunking, client side image scaling and it uses different runtimes to achieve this such as HTML 5, Silverlight and F

var util = require('util');

/**
Executes the callback function for each item in array/object. If you return false in the
callback it will break the loop.

@author Moxiecode
@method each
@param {Object} obj Object to iterate.
@param {function} callback Callback function to execute for each item.
 */
var each = function(obj, callback) {
	var length, key, i;

	if (obj) {
		length = obj.length;

		if (length === undefined) {
			// Loop object items
			for (key in obj) {
				if (obj.hasOwnProperty(key)) {
					if (callback(obj[key], key) === false) {
						return;
					}
				}
			}
		} else {
			// Loop array items
			for (i = 0; i < length; i++) {
				if (callback(obj[i], i) === false) {
					return;
				}
			}
		}
	}
};

/**
Extends the specified object with another object.

@author Moxiecode
@method extend
@param {Object} target Object to extend.
@param {Object} [obj]* Multiple objects to extend with.
@return {Object} Same as target, the extended object.
*/
var extend = function(target) {
	var undef;

	each(arguments, function(arg, i) {
		if (i > 0) {
			each(arg, function(value, key) {
				if (value !== undef) {
					if (typeof(target[key]) === typeof(value) && (typeof(value) === 'object' || util.isArray(value))) {
						extend(target[key], value);
					} else {
						target[key] = value;
					}
				}
			});
		}
	});
	return target;
};

/**
Generates an unique ID. This is 99.99% unique since it takes the current time and 5 random numbers.
The only way a user would be able to get the same ID is if the two persons at the same exact milisecond manages
to get 5 the same random numbers between 0-65535 it also uses a counter so each call will be guaranteed to be page unique.
It's more probable for the earth to be hit with an ansteriod. Y

@author Moxiecode
@method guid
@param {String} prefix to prepend (by default 'o' will be prepended).
@method guid
@return {String} Virtually unique id.
 */
var guid = (function() { 
	var counter = 0;
	
	return function(prefix) {
		var guid = new Date().getTime().toString(32), i;

		for (i = 0; i < 5; i++) {
			guid += Math.floor(Math.random() * 65535).toString(32);
		}
		
		return (prefix || '') + guid + (counter++).toString(32);
	};
}());


var inSeries = function(queue, cb) {
	var i = 0, length = queue.length;

	if (typeof(cb) !== 'function') {
		cb = function() {};
	}

	function callNext(i) {
		if (typeof(queue[i]) === 'function') {
			queue[i](function(error) {
				++i < length && !error ? callNext(i) : cb(error);
			});
		}
	}
	callNext(i);
};


function asFlags(arr) {
	var obj = {};
	each(arr, function(flag) {
		obj[flag] = true;
	});
	return obj;
}


extend(util, {
	  guid: guid
	, each: each
	, extend: extend
	, inSeries: inSeries
	, asFlags: asFlags
});

module.exports = util;