/**
 * Actual function that does all the work. Returns an array with all the info.
 * This test will fail for the font set as the default serif font.
 * 
 * Usage: d = new Detector();
 *        d.test('font_name');
 */
var Detector = function(){
	var h = document.getElementsByTagName("HTML")[0];
	var d = document.createElement("DIV");
	var s = document.createElement("SPAN");
	d.appendChild(s);
	d.style.fontFamily = "sans";			//font for the parent element DIV.
	s.style.fontFamily = "sans";			//serif font used as a comparator.
	s.style.fontSize   = "72px";			//we test using 72px font size, we may use any size. I guess larger the better.
	s.innerHTML        = "mmmmmmmmmmlil";		//we use m or w because these two characters take up the maximum width. And we use a L so that the same matching fonts can get separated
	h.appendChild(d);
	var defaultWidth   = s.offsetWidth;		//now we have the defaultWidth
	var defaultHeight  = s.offsetHeight;	//and the defaultHeight, we compare other fonts with these.
	h.removeChild(d);
	/* test
	 * params:
	 * font - name of the font you wish to detect
	 * return: 
	 * f[0] - Input font name.
	 * f[1] - Computed width.
	 * f[2] - Computed height.
	 * f[3] - Detected? (true/false).
	 */
	function debug(font) {
		h.appendChild(d);
		var f = [];
		f[0] = s.style.fontFamily = font;	// Name of the font
		f[1] = s.offsetWidth;				// Width
		f[2] = s.offsetHeight;				// Height
		h.removeChild(d);
		font = font.toLowerCase();
		if (font == "serif") {
			f[3] = true;	// to set arial and sans-serif true
		} else {
			f[3] = (f[1] != defaultWidth || f[2] != defaultHeight);	// Detected?
		}
		return f;
	}
	function test(font){
		f = debug(font);
		return f[3];
	}
	this.detailedTest = debug;
	this.test = test;	
}

//Browser Detection
var BrowserDetect = {
	init: function () {
		this.browser = this.searchString(this.dataBrowser) || "An unknown browser";
		this.version = this.searchVersion(navigator.userAgent)
			|| this.searchVersion(navigator.appVersion)
			|| "an unknown version";
		this.OS = this.searchString(this.dataOS) || "an unknown OS";
	},
	searchString: function (data) {
		for (var i=0;i<data.length;i++)	{
			var dataString = data[i].string;
			var dataProp = data[i].prop;
			this.versionSearchString = data[i].versionSearch || data[i].identity;
			if (dataString) {
				if (dataString.indexOf(data[i].subString) != -1)
					return data[i].identity;
			}
			else if (dataProp)
				return data[i].identity;
		}
	},
	searchVersion: function (dataString) {
		var index = dataString.indexOf(this.versionSearchString);
		if (index == -1) return;
		return parseFloat(dataString.substring(index+this.versionSearchString.length+1));
	},
	dataBrowser: [
		{
			string: navigator.userAgent,
			subString: "Chrome",
			identity: "Chrome"
		},
		{ 	string: navigator.userAgent,
			subString: "OmniWeb",
			versionSearch: "OmniWeb/",
			identity: "OmniWeb"
		},
		{
			string: navigator.vendor,
			subString: "Apple",
			identity: "Safari",
			versionSearch: "Version"
		},
		{
			prop: window.opera,
			identity: "Opera"
		},
		{
			string: navigator.vendor,
			subString: "iCab",
			identity: "iCab"
		},
		{
			string: navigator.vendor,
			subString: "KDE",
			identity: "Konqueror"
		},
		{
			string: navigator.userAgent,
			subString: "Firefox",
			identity: "Firefox"
		},
		{
			string: navigator.vendor,
			subString: "Camino",
			identity: "Camino"
		},
		{		// for newer Netscapes (6+)
			string: navigator.userAgent,
			subString: "Netscape",
			identity: "Netscape"
		},
		{
			string: navigator.userAgent,
			subString: "MSIE",
			identity: "Explorer",
			versionSearch: "MSIE"
		},
		{
			string: navigator.userAgent,
			subString: "Gecko",
			identity: "Mozilla",
			versionSearch: "rv"
		},
		{ 		// for older Netscapes (4-)
			string: navigator.userAgent,
			subString: "Mozilla",
			identity: "Netscape",
			versionSearch: "Mozilla"
		}
	],
	dataOS : [
		{
			string: navigator.platform,
			subString: "Win",
			identity: "Windows"
		},
		{
			string: navigator.platform,
			subString: "Mac",
			identity: "Mac"
		},
		{
			   string: navigator.userAgent,
			   subString: "iPhone",
			   identity: "iPhone/iPod"
	    },
		{
			string: navigator.platform,
			subString: "Linux",
			identity: "Linux"
		}
	]

};
BrowserDetect.init();