// init adsense click tracking after docuement load...
attachOnloadEvent(adsenseTrackerInit);

// helper global variables
var adsenseTrackerActive = true;
var adsenseTrackerUnit = '';

// prefixes and suffixes language filter array
var lngFilter = Array('go to','View ads about','gehe zu','Afficher la page','Afficher des annonces sur','Anzeigen über',
'gaan na','|ma Ja','war-du','vs a','Jdi na','Zobrazit reklamy na téma','ewch i','g til','Se annoncer om','iru al','ir a',
'Ver anuncios sobre','liigu edasi aadressile','bisitatu','mene osoitteeseen','Tarkastele mainoksia aiheesta','far til',
'gean nei','tigh chuig','rach gu','Jeho ko\'pe:','idemo na','Ugrs:','vade a','fara','visita','Visualizza annunci su',
'Ayo menyang','ire ad','kumbama na','eiti','Dodieties uz','|- ilekku povuka','pergi ke','mur sa','ga naar',
'Bekijk advertenties over','g til','Se annonser om','anar a','|ku jAntu','przejd do','Pokarz reklamy o','ir para',
'Ver anúncios sobre','riy|man','va a','du-te la','posjeti','|yanna','prejdi na','Zobraziť reklamy s témou','pojdi na',
'endai ku','Aad','shko n','e ya ho','lebet ka','g till','Se annonser om','nenda','|a git','pumunta sa','\'alu ki he',
'|adresine git','Şu konuyla ilgili reklamları görüntüle:','ko','|ga boring','yiya kwi','lo si');

// filter phrase with lngFilter
function filterPhrase(phrase) {
    var suprefixes, filterhit;
    
    phrase = phrase.replace(/^\s+|\s+$/g, '');
    if (phrase != '') {
        for(var i=0; i<lngFilter.length; i++) {
            suprefixes = lngFilter[i].split('|');
            // check prefix
            if (suprefixes[0].length > 0 && phrase.substring(0, suprefixes[0].length) == suprefixes[0]) {
                phrase = phrase.substring(suprefixes[0].length);
                filterhit = true;
            }
            // check suffix
            if (suprefixes.length > 1 && suprefixes[1].length > 0 && phrase.substring(phrase.length - suprefixes[1].length) == suprefixes[1]) {
                phrase = phrase.substring(0, phrase.length - suprefixes[1].length);
                filterhit = true;
            }    
            if (filterhit) {
                phrase = phrase.replace(/^\s+|\s+$/g, '');
                break;
            }        
        }
    }
    return phrase;
}

// init tracker
function adsenseTrackerInit() {
	var pageHasAdsense = false;
	var el = document.getElementsByTagName("iframe");

	for (var i=0; i<el.length; i++) {
		if (el[i].src.indexOf('googlesyndication.com') > -1) {
			pageHasAdsense = true;
			el[i].onmouseover = adsenseTrackerActivate;
			el[i].onmouseout = adsenseTrackerDeActivate;
		}
	}

	if (pageHasAdsense) {
		if (typeof window.attachEvent != 'undefined') {
			// this works for IE
			window.attachEvent('onbeforeunload', adsenseTrackerCheckClick);
		} else if (typeof window.addEventListener != 'undefined') {
			// this works for firefox
			window.addEventListener('beforeunload', adsenseTrackerCheckClick, false);
		}
	}
}

// check if it's our click
function adsenseTrackerCheckClick() {
	if (adsenseTrackerActive) {
			var adsize="", url="";
		if (adsenseTrackerUnit != '')
			adsize=escape(adsenseTrackerUnit);

		// check for ad Url/AdLinks text (is disabled in Firefox by default)
		if (window.status) {
		    var adsenseClickedAd = filterPhrase(window.status);
			if (adsenseClickedAd != '') {
			    url=escape(adsenseClickedAd);
			}
		}

		logClick(url, adsenseTrackerUnit);
		
	}
}

function logClick(ad_target_url, adsize)
{
	ppcta_url_image = new Image();
	ppcta_url_image.src = 'http://www.worldadvice.co.uk/ppcta_adsense_click_logger.php?dbid=&ref=' +
			escape(document.location) + '&url=' + escape(ad_target_url)
			+ '&adsize=' + adsize
			+ '&site=';
}

// when moving mouse to adsense frame, activate click tracking for current ad unit...
function adsenseTrackerActivate() {
	adsenseTrackerUnit = '';

	if (this.parentNode) {
		// check for custom asc_ adsense element id
		if (this.parentNode.id.substring(0, 4) == 'asc_') {
			adsenseTrackerUnit = this.parentNode.id.substring(4);
		}
	}
	if (adsenseTrackerUnit == '') {
		// decode format parameter from adsense ads url
		var url = this.src;
		var startIndex = url.indexOf('format=');
		if (startIndex >= 0) {
			var lastIndex = url.indexOf('&', startIndex);
			adsenseTrackerUnit = lastIndex >= 0 ? url.substring(startIndex + 7, lastIndex) : url.substring(startIndex + 7);
		}
	}
	adsenseTrackerActive = true;
}

// when moving mouse out of adsense frame, deactivate click tracking...
function adsenseTrackerDeActivate() {
	adsenseTrackerUnit = '';
	adsenseTrackerActive = false;
}

// attach func function to window onload event (crossbrowser compatible)
function attachOnloadEvent(func) {
	if(typeof window.addEventListener != 'undefined') {
		// moz, saf1.2, ow5b6.1
		window.addEventListener('load', func, false);
	} else if (typeof document.addEventListener != 'undefined') {
		// MSN/OSX, op7.50, saf1.2, ow5b6.1
		document.addEventListener('load', func, false);
	} else if (typeof window.attachEvent != 'undefined') {
		// ie5.0w, ie5.5w, ie6w
		window.attachEvent('onload', func);
	} else {
		// all other browsers
		if (typeof window.onload == 'function') {
			var oldonload = onload;
			window.onload = function() {
				oldonload();
				func();
			};
		} else {
				window.onload = func;
		}
	}
}