// Generic Form Validation
// Jacob Hage (jacob@hage.dk)
var checkObjects	= new Array();
var errors		= "";
var returnVal		= false;
var language		= new Array();
language["header"]	= "The following error(s) occured:"
language["start"]	= "->";
language["field"]	= " Field ";
language["require"]	= " is required";
language["min"]		= " and must consist of at least ";
language["max"]		= " and must not contain more than ";
language["minmax"]	= " and no more than ";
language["chars"]	= " characters";
language["num"]		= " and must contain a number";
language["email"]	= " must contain a valid e-mail address";
// -----------------------------------------------------------------------------
// define - Call this function in the beginning of the page. I.e. onLoad.
// n = name of the input field (Required)
// type= string, num, email (Required)
// min = the value must have at least [min] characters (Optional)
// max = the value must have maximum [max] characters (Optional)
// d = (Optional)
// -----------------------------------------------------------------------------
function define(n, type, HTMLname, min, max, d) {
var p;
var i;
var x;
if (!d) d = document;
if ((p=n.indexOf("?"))>0&&parent.frames.length) {
d = parent.frames[n.substring(p+1)].document;
n = n.substring(0,p);
}
if (!(x = d[n]) && d.all) x = d.all[n];
for (i = 0; !x && i < d.forms.length; i++) {
x = d.forms[i][n];
}
for (i = 0; !x && d.layers && i < d.layers.length; i++) {
x = define(n, type, HTMLname, min, max, d.layers[i].document);
return x;       
}
eval("V_"+n+" = new formResult(x, type, HTMLname, min, max);");
checkObjects[eval(checkObjects.length)] = eval("V_"+n);
}
function formResult(form, type, HTMLname, min, max) {
this.form = form;
this.type = type;
this.HTMLname = HTMLname;
this.min  = min;
this.max  = max;
}
function validate() {
if (checkObjects.length > 0) {
errorObject = "";
for (i = 0; i < checkObjects.length; i++) {
validateObject = new Object();
validateObject.form = checkObjects[i].form;
validateObject.HTMLname = checkObjects[i].HTMLname;
validateObject.val = checkObjects[i].form.value;
validateObject.len = checkObjects[i].form.value.length;
validateObject.min = checkObjects[i].min;
validateObject.max = checkObjects[i].max;
validateObject.type = checkObjects[i].type;
if (validateObject.type == "num" || validateObject.type == "string") {
if ((validateObject.type == "num" && validateObject.len <= 0) || (validateObject.type == "num" && isNaN(validateObject.val))) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['require'] + language['num'] + "\n";
} else if (validateObject.min && validateObject.max && (validateObject.len < validateObject.min || validateObject.len > validateObject.max)) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['require'] + language['min'] + validateObject.min + language['minmax'] + validateObject.max+language['chars'] + "\n";
} else if (validateObject.min && !validateObject.max && (validateObject.len < validateObject.min)) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['require'] + language['min'] + validateObject.min + language['chars'] + "\n";
} else if (validateObject.max && !validateObject.min &&(validateObject.len > validateObject.max)) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['require'] + language['max'] + validateObject.max + language['chars'] + "\n";
} else if (!validateObject.min && !validateObject.max && validateObject.len <= 0) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['require'] + "\n";
   }
} else if(validateObject.type == "email") {
// Checking existense of "@" and ".". 
// Length of must >= 5 and the "." must 
// not directly precede or follow the "@"
if ((validateObject.val.indexOf("@") == -1) || (validateObject.val.charAt(0) == ".") || (validateObject.val.charAt(0) == "@") || (validateObject.len < 6) || (validateObject.val.indexOf(".") == -1) || (validateObject.val.charAt(validateObject.val.indexOf("@")+1) == ".") || (validateObject.val.charAt(validateObject.val.indexOf("@")-1) == ".")) { errors += language['start'] + language['field'] + validateObject.HTMLname + language['email'] + "\n"; }
      }
   }
}
if (errors) {
alert(language["header"].concat("\n" + errors));
errors = "";
returnVal = false;
} else {
returnVal = true;
   }
}
