"use strict";

var utils = {
	getGUID: function() {
		function s4() {
			return Math.floor((1 + Math.random()) * 0x10000)
				.toString(16)
				.substring(1);
		}

		return s4() + s4() + '-' + s4() + '-' + s4() + '-' +
		s4() + '-' + s4() + s4() + s4();
	},
	indexOf: function(array, searchElement, fromIndex) {
		if (Array.prototype.indexOf) {
			return array.indexOf(searchElement, fromIndex);
		} else {
			var k;
			var O = Object(array);

			// 2. Let lenValue be the result of calling the Get
			//    internal method of O with the argument "length".
			// 3. Let len be ToUint32(lenValue).
			var len = O.length >>> 0;

			// 4. If len is 0, return -1.
			if (len === 0) {
				return -1;
			}

			// 5. If argument fromIndex was passed let n be
			//    ToInteger(fromIndex); else let n be 0.
			var n = +fromIndex || 0;

			if (Math.abs(n) === Infinity) {
				n = 0;
			}

			// 6. If n >= len, return -1.
			if (n >= len) {
				return -1;
			}

			// 7. If n >= 0, then Let k be n.
			// 8. Else, n<0, Let k be len - abs(n).
			//    If k is less than 0, then let k be 0.
			k = Math.max(n >= 0 ? n : len - Math.abs(n), 0);

			// 9. Repeat, while k < len
			while (k < len) {
				var kValue;
				// a. Let Pk be ToString(k).
				//   This is implicit for LHS operands of the in operator
				// b. Let kPresent be the result of calling the
				//    HasProperty internal method of O with argument Pk.
				//   This step can be combined with c
				// c. If kPresent is true, then
				//    i.  Let elementK be the result of calling the Get
				//        internal method of O with the argument ToString(k).
				//   ii.  Let same be the result of applying the
				//        Strict Equality Comparison Algorithm to
				//        searchElement and elementK.
				//  iii.  If same is true, return k.
				if (k in O && O[k] === searchElement) {
					return k;
				}
				k++;
			}
			return -1;
		}
	},

	// from http://ejohn.org/projects/flexible-javascript-events/
	addEvent: function( obj, type, fn ) {
		if ( obj.attachEvent ) {
			obj['e'+type+fn] = fn;
			obj[type+fn] = function(){obj['e'+type+fn]( window.event );}
			obj.attachEvent( 'on'+type, obj[type+fn] );
		} else
			obj.addEventListener( type, fn, false );
	},

	// from http://ejohn.org/projects/flexible-javascript-events/
	removeEvent: function( obj, type, fn ) {
		if ( obj.detachEvent ) {
			obj.detachEvent( 'on'+type, obj[type+fn] );
			obj[type+fn] = null;
		} else
			obj.removeEventListener( type, fn, false );
	}

};