var xmlhttp;

function submit_post() {
	var pUser, pPass, pMessage;

	pUser = document.getElementById("user").value;
	pPass = document.getElementById("pass").value;
	pMessage = escape(document.getElementById("message").value);

	twitter_disable();

	document.getElementById("result").innerHTML="Twittering..";

	twitter_post(pUser, pPass, pMessage);
}

function twitter_post(theuser, thepassword, themessage) {
	
	post = 'username='+theuser+'&password='+thepassword+'&message='+themessage;


	var xmlhttp = new XMLHttpRequest();
	xmlhttp.open('GET', 'backend/api.php?'+post, true);

	xmlhttp.onreadystatechange = function () {

	if (xmlhttp.readyState == 4) {

		var twitterDOM = xmlhttp.responseXML;

		var result = twitterDOM.getElementsByTagName("error").length;

		if (!result) {
			twitter_success();
		} else {
			twitter_fail();
			twitter_enable();
		}	

	}

};

	xmlhttp.send(post);

}

//GUI

function twitter_disable() {
	document.getElementById("submit").style.visibility = "hidden";
}

function twitter_enable() {
	document.getElementById("submit").style.visibility = "visible";
}

function twitter_fail() {
	document.getElementById("result").innerHTML="Failed to tweet!";
	twitter_disable();
}

function twitter_success() {
	document.getElementById("result").innerHTML="Tweet posted successfully!";
	twitter_enable();
}