function eToggle(id, visible, exercise) {
	if (visible == 1) {
		window.document.getElementById('part'+id).style.display = "block";
		window.document.getElementById('partdetails').innerHTML = exercise;
	} else {
		window.document.getElementById('part'+id).style.display = "none";
		window.document.getElementById('partdetails').innerHTML = " ";
	}
}

function eOpen(file) {
	s0.addVariable('file', file);
	s0.addVariable('autostart', "true");
	s0.write("video0");
}

function echeck(str) {
	var at="@"
	var dot="."
	var lat=str.indexOf(at)
	var lstr=str.length
	var ldot=str.indexOf(dot)
	if (str.indexOf(at)==-1) {
	   return false;
	}
	if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr) {
	   return false;
	}
	if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr) {
		return false;
	}
	 if (str.indexOf(at,(lat+1))!=-1) {
		return false;
	 }
	 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot) {
		return false;
	 }
	 if (str.indexOf(dot,(lat+2))==-1) {
		return false;
	 }
	 if (str.indexOf(" ")!=-1) {
		return false;
	 }
	 return true;
}

function checklogin() {
	var email = window.document.getElementById('myemail').value;
	var password = window.document.getElementById('mypassword').value;
	if (echeck(email) == true && password.length >= 4) {
		return true;
	} else {
		window.document.getElementById('errormsg').innerHTML = 'Wrong e-mail address or password.';
		window.document.getElementById('errormsg').style.display = 'block';
		return false;
	}
}

function checkregister() {
	var regemail = window.document.getElementById('myregemail').value;
	var regpassword = window.document.getElementById('myregpassword').value;
	if (echeck(regemail) == true && regpassword.length >= 4) {
		return true;
	} else {
		window.document.getElementById('regerrormsg').innerHTML = 'Please enter your e-mail address and password.';
		window.document.getElementById('regerrormsg').style.display = 'block';
		return false;
	}
}