criteriant="guided_empty";
function mostracriteri(quin){
	document.getElementById(criteriant).disabled=1;
	document.getElementById("l"+criteriant).style.display="none";
	if(criteriant=="guided_stage")
	{
		document.getElementById("guided_subject").disabled=1;
		document.getElementById("lguided_subject").style.display="none";
	}
	criteriant=quin;
	
	if(quin!="guided_empty")
	{
		document.getElementById(quin).disabled=0;	
	}
	document.getElementById("l"+quin).style.display="block";
	if(quin=="guided_stage")
	{
		document.getElementById("lguided_subject").style.display="block";
	}
}

function carrega_assignatures(campo, pos, subject)
{
	omplircamp = (campo.id=="heads_course") ? "heads_subject" :  "guided_subject";
	
	cleanselect( omplircamp );
	stagecourse = campo.value;
	value_stage = "";
	value_course = "";
	
	value_stage = getValue(stagecourse, "stage:");
	value_course = getValue(stagecourse, "course:");
	
	if(value_course == "") arrayAssig = eval("ar_assig_st" + value_stage);
	else arrayAssig = eval("ar_st" + value_stage + "_c" + value_course);
	
	for(k=0;k < arrayAssig.length;k=k+3){		
		isSelected = false;		
		if(subject != '' && getValue(arrayAssig[k], "subject:") == subject ){
			isSelected = true;
		}						
		document.getElementById(omplircamp).options[k/3+1] = new Option(arrayAssig[k+pos],arrayAssig[k]);
		ooption = document.getElementById(omplircamp).options[k/3+1];
		if(isSelected) ooption.selected = true;
	}
}

function getValue(value, search)
{
	first = value.indexOf(search, 0);	
	if(first == -1) return "";
	
	search_size = search.length;	
	value_size = value.length;		
	first = first + search_size;		
	if( first >= value_size) return "";
	
	aux = value.indexOf(";", first);
	end = (aux == -1) ? value_size : aux;
		
	return value.substring(first, end);		
}

function DelField(camp,textor){
	idcamp=camp.id;
	if(document.getElementById(idcamp).value==" -- "+textor+" --"){
		document.getElementById(idcamp).value="";
		document.getElementById(idcamp+"_modified").value=1;
		//alert("modificado");
	}
}
function ResField(camp,textor){
	idcamp=camp.id;
	if(document.getElementById(idcamp).value==""){
		document.getElementById(idcamp).value=" -- "+textor+" --";
		document.getElementById(idcamp+"_modified").value=0;
		//alert("NO modificado");
	}
}
function cleanselect(idcamp){
	document.getElementById(idcamp).length=1;
	document.getElementById(idcamp).disabled=0;
}
function desactiva(idcamp){
	document.getElementById(idcamp).selectedIndex=0;
}