function validate(){

	var fname = document.getElementById('fname').value;
	var lname = document.getElementById('lname').value;
	var email = document.getElementById('email').value;
	
	if (fname=="" || lname=="" || email=="" || email.indexOf('@')==-1){
	
		alert('Por favor ingrese los campos requeridos');
		return false;
	
	}

	return true;

}

function setCalendar(){

	var day = 1000*60*60*24;

	var date1 = document.getElementById('f_date_c').value;
	var date2 = document.getElementById('f_date_c2').value;
	
	if (date2=="") return false;
	
	var from = Date.parse(date1);	
	var to = Date.parse(date2);
	
	var tdif = Math.ceil((from-to)/(day));
	
	if (tdif>=0){ 
	
		alert('Fecha Inválida'); 
		document.getElementById('f_date_c2').value = "";
		return false;
	}
	
	var dif = Math.abs(tdif);
	
	var w = dif%7;
	
	if (w==0){
	
		return true;
	
	}else{
	
		fix(dif,to);
	
	}	
	
	function fix(dif,date){
	
		var sum = 7-dif;
		
		if (sum<0){
		
			sum = (sum%7)+7;
			
		}
		
		var days = day * sum;
		
		var total = days + date; 
		
		var tdate = new Date(total);
		
		tdate = tdate.toString();
		
		var d = tdate.split(" ",4);
		
		var new_date = d[1]+" "+d[2]+", "+d[3];
		
		document.getElementById('f_date_c2').value = new_date;
	
	}
	
}