function createXMLHttpRequest() {
	var ua;
	if(window.XMLHttpRequest) {
		try {
			ua = new XMLHttpRequest();
		} catch(e) {
			ua = false;
		}
	} else if(window.ActiveXObject) {
		try {
			ua = new ActiveXObject("Microsoft.XMLHTTP");
		} catch(e) {
            ua = false;
		}
	}
	return ua;
}

var req = createXMLHttpRequest();
var myts = 0;

function showForm() {
	if(document.getElementById('empfehlen').style.display == 'none') {
		document.getElementById('inhalt').style.display = '';
		document.getElementById('showconf').style.display = 'none';
		document.getElementById('checkimg').style.display = 'none';
		document.getElementById('empfehlen').style.display = '';
		document.getElementById('empfehlen_hide').style.display = 'none';
	} else {
		document.getElementById('inhalt').style.display = 'none';
		document.getElementById('showconf').style.display = 'none';
		document.getElementById('checkimg').style.display = 'none';
		document.getElementById('empfehlen').style.display = 'none';
		document.getElementById('empfehlen_hide').style.display = '';
	}
}

  
function checkImage() {
	myts = Math.floor(new Date().getTime()/1000);
	document.getElementById('checkimg').style.display = '';
	document.getElementById('inhalt').style.display = 'none';
	document.getElementById('showconf').style.display = 'none';
	document.getElementById('checkimg').innerHTML = 'Bitte geben Sie die Zeichen als Best&auml;tigung ein:<img style="margin-top:5px;" src="http://entwickler.de/zonen/ext_scripts/newsbeitraege/randomstring.php?ts='+myts+'"><br/><input type="text" name="checkstring" id="checkstring"><br/><input type="submit" value="absenden" onclick="sendRequest()" class="submit" />';
}
 
function sendRequest() {
	var parameters = "to=" + encodeURI( document.getElementById("to").value ) + "&from=" + encodeURI( document.getElementById("from").value ) + "&location=" + encodeURI(self.location) + "&checkstring=" + encodeURI(document.getElementById("checkstring").value) + "&ts=" + encodeURI(myts);
	req.onreadystatechange = handleResponse;
//	req.open('POST', 'http://entwickler-press.de/ep/scripts/send_book_introduction.php', true);
	req.open('POST', '/ep/scripts/send_book_introduction.php', true);
	req.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
	req.setRequestHeader("Content-length", parameters.length);
	req.setRequestHeader("Connection", "close");
	req.send(parameters);
}

function handleResponse() {
	if(req.readyState == 4) {
		document.getElementById('showconf').innerHTML = req.responseText;
		document.getElementById('inhalt').style.display = 'none';
		document.getElementById('checkimg').style.display = 'none';
		document.getElementById('showconf').style.display = '';
	}
}