// For validating input in the Volunteer/Get Involved form.

function validData() {
    var s = document.getElementById("firstname").value;
    if (!validName(s)) {
       alert("Invalid first name!");
       document.getElementById("firstname").focus();
       return false;
    }  
    s = document.getElementById("lastname").value; 
    if (!validName(s)) {
       alert("Invalid last name!");
       document.getElementById("lastname").focus();
       return false;
    }   
    s = document.getElementById("zip").value;
    if (s != "" && !validZip(s)) return false;
    return true;
}

function validName(name) {
    if (name == "") return false;
    name = name.toUpperCase();
	var i;
    for (i=0; i<name.length; i++) {
        var ch = name.charAt(i);
        if ((ch < 'A' || ch > 'Z') &&
            (ch != ' ' && ch != '-' && ch != '.' && ch != ',' && ch != '\''))
            return false;
    }
    return true;
}

function validZip() {
    var zip = document.getElementById("zip").value;
    var parts = zip.split("-");
    if (parts[0].length != 5) return false;
    if (!isNumeric(parts[0])) return false;
    if (parts.length == 1) return true;
    if (parts[1].length != 4) return false;
    if (!isNumeric(parts[1])) return false;
    return true;
}

function isNumeric (str) {
   var i;
   for (i=0; i<str.length; i++) {
       var ch = str.charAt(i);
       if (ch < '0' || ch > '9') return false;
   }
   return true;
}