function trim(value){
		value = value.replace(/^\s+/, '');
		return value.replace(/\s+$/, '');
	}

	function element(id){
		var element = document.getElementById(id);
		return element;
	}

	function valueof(id){
		var value = document.getElementById(id).value;
		return value;
	}

	function display(element){
		if(element.style.display=='none'){
			element.style.display='';
		}
		else{
			element.style.display='none';
		}
	}

	function displayit(field,fields){
		for(i=0; i<fields.length; i++){
			var tmpfield = element(fields[i]);
			if(fields[i]==field){
				tmpfield.style.display='';
			}
			else{
				tmpfield.style.display='none';
			}
		}
	}

	function checkmail(id){
		errors = 0;
		email = element(id);
		email.value = trim(email.value);
		if(!email.value.match(/^(([A-Za-z0-9]+_+)|([A-Za-z0-9]+\-+)|([A-Za-z0-9]+\.+)|([A-Za-z0-9]+\++))*[A-Za-z0-9]+@((\w+\-+)|(\w+\.))*\w{1,63}\.[a-zA-Z]{2,6}$/)){
			errors++;
		}
		if(errors>0){
			email.className='failure';
			email.focus();
			return false;
		}
		else{
			email.className='success';
			return true;
		}
	}

	function checkit(id){
		text = element(id);
		if(text.value.toString()==''){
			text.className='failure';
			text.focus();
			return false;
		}
		else{
			text.className='success';
			return true;
		}
	}

	function scheckit(id){
		text = element(id);
		if(text.value==0){
			text.className='failure';
			text.focus();
			return false;
		}
		else{
			text.className='success';
			return true;
		}
	}

	function doajax(){
		var xmlhttp=false;
		try{
			xmlhttp = new ActiveXObject('Msxml2.XMLHTTP');
		}catch(e){
			try{
				xmlhttp = new ActiveXObject('Microsoft.XMLHTTP');
			}catch(E){
				xmlhttp = false;
			}
		}
		if(!xmlhttp && typeof XMLHttpRequest!='undefined'){
			xmlhttp = new XMLHttpRequest();
		}
		return xmlhttp;
	}


	function searchUnregisteredStudents(subject, objectResult, srch){
		try{
		objectResult.innerHTML="buscando...";
		ajax=doajax();
		if(ajax){
			ajax.open('GET', 'ajax.php?requestSection='+ADM_SECTION_SUBJECTS+'&request='+ADM_SECTION_STUDENTS+'&subject='+subject+'&unregisteredStudents=true&srch='+srch);
			ajax.onreadystatechange=function(){
				if(ajax.readyState==4){
					objectResult.innerHTML=ajax.responseText;
				}
			}
		}
		ajax.send(null);
		}catch(e){
			alert(e);
		}
		
	}
	
	function searchUnregisteredTeachers(subject, objectResult, srch){
		try{
		objectResult.innerHTML="buscando...";
		ajax=doajax();
		if(ajax){
			ajax.open('GET', 'ajax.php?requestSection='+ADM_SECTION_SUBJECTS+'&request='+ADM_SECTION_TEACHERS+'&subject='+subject+'&unregisteredTeachers=true&srch='+srch);
			ajax.onreadystatechange=function(){
				if(ajax.readyState==4){
					objectResult.innerHTML=ajax.responseText;
				}
			}
		}
		ajax.send(null);
		}catch(e){
			alert(e);
		}
		
	}



	function join(student, subject, period, checkbox, registered, unregistered){
		checkbox = element(checkbox);
		registered = element(registered);
		unregistered = element(unregistered);
		row = element('student-'+student);
		ajax=doajax();
		if(ajax){
			if(checkbox.checked==true){
				ajax.open('GET', 'php/student-process.php?process=register&student='+student+'&subject='+subject+'&period='+period);
			}
			else{
				ajax.open('GET', 'php/student-process.php?process=unregister&student='+student+'&subject='+subject+'&period='+period);
			}
			ajax.onreadystatechange=function(){
				if(ajax.readyState==4){
					if(ajax.responseText=='true'){
						if(checkbox.checked==true){
							checkbox.checked=true;
							registered.appendChild(row);
						}
						else{
							checkbox.checked=false;
							unregistered.appendChild(row);
						}
					}
					else{
						if(checkbox.checked==true){
							checkbox.checked=false;
						}
						else{
							checkbox.checked=true;
						}
					}
				}
			}
		}
		ajax.send(null);
	}
	
	
	function getLeft(elemento){
 	try{

 		if (elemento.offsetParent){
 			return (elemento.offsetLeft + (this.getLeft(elemento.offsetParent))) ;
	 	} else{
	 		return (elemento.offsetLeft) ;
	    }
 	}catch(e){
 		return e;
 	}


}
function getTop(elemento){
 	try{
 		if (elemento.offsetParent){
 		return (elemento.offsetTop + (this.getTop(elemento.offsetParent))) ;
	 	} else{
	 		return (elemento.offsetTop) ;
	    }
 	}catch(e){
 		return e;
 	}


}

function showAvatar(src_, element){
	var av=document.getElementById('avatardiv');
	av.style.visibility="visible";
	var im=av.getElementsByTagName('img')[0];
	if(src_.length==0){
		im.src='img/perfil.jpg';
	}else{
		im.src=src_;
	}
	
	av.style.top=getTop(element);
	av.style.left=getLeft(element)+90;
	
}
function hiddeAvatar(){
	var av=document.getElementById('avatardiv');
	av.style.visibility="hidden";
	var im=av.getElementsByTagName('img')[0];
	im.src='img/perfil.jpg';
	
	
}
function show_hidde(object){
	if(object.style.display=="none"){
		object.style.display="block";
	}else{
		object.style.display="none";
	}
}