var nbsp = 160;		// non-breaking space char
var node_text = 3;	// DOM text node-type
var emptyString = /^\s*$/ ;
var global_valfield;	// retain valfield for timer thread

function enableDates(is_checked, myform) 
{
	if (is_checked) {
		myform.from.disabled = false
		myform.to.disabled = false
	}
	else {
		myform.from.value = 'yyyy-mm-dd'
		myform.to.value = 'yyyy-mm-dd'
		myform.from.disabled = true
		myform.to.disabled = true
	}
}

function enableLimitDates(is_checked, myform)
{
	if (is_checked) {
		myform.limit_dates.disabled = false
		enableDates(myform.limit_dates.checked, myform)
	}
	else {
		myform.limit_dates.disabled = true
		myform.from.disabled = true
		myform.to.disabled = true
	}
}

function disableEnable(is_checked, from, to) 
{ 
 	if (is_checked == false) {
		from.disabled = true;
		to.disabled = true;
		to.value = "yyyy-mm-dd";
		from.value = "yyyy-mm-dd";
	}
	else {
		from.disabled = false;
		to.disabled = false;
	}
}
 
function trim(str)  // Trim leading/trailing whitespace off string
{
  return str.replace(/^\s+|\s+$/g, '');
}

function setFocusDelayed()  // Delayed focus setting to get around IE bug
{
  global_valfield.focus();
}

function setfocus(valfield)
{
  // save valfield in global variable so value retained when routine exits
  global_valfield = valfield;
  setTimeout( 'setFocusDelayed()', 100 );
}

function msg(fld,     // id of element to display message in
             msgtype, // class to give element ("warn" or "error")
             message) // string to display
{
  // setting an empty string can give problems if later set to a 
  // non-empty string, so ensure a space present. (For Mozilla and Opera one could 
  // simply use a space, but IE demands something more, like a non-breaking space.)
  var dispmessage;
  if (emptyString.test(message)) 
    dispmessage = String.fromCharCode(nbsp);    
  else  
    dispmessage = message;

  var elem = document.getElementById(fld);
  elem.firstChild.nodeValue = dispmessage;  
  elem.className = msgtype;   // set the CSS class to adjust appearance of message
}

// --------------------------------------------
//            commonCheck
// Common code for all validation routines to:
// (a) check for older / less-equipped browsers
// (b) check if empty fields are required
// Returns true (validation passed), 
//         false (validation failed) or 
//         proceed (don't know yet)
// --------------------------------------------

var proceed = 2;  

function commonCheck    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  if (!document.getElementById) 
    return true;  // not available on this browser - leave validation to the server
  var elem = document.getElementById(infofield);
  if (!elem.firstChild) return true;  // not available on this browser 
  if (elem.firstChild.nodeType != node_text) return true;  // infofield is wrong type of node  

  if (emptyString.test(valfield.value)) {
    if (required) {
      msg (infofield, "error", "Required");  
      setfocus(valfield);
      return false;
    }
    else {
      msg (infofield, "warn", "");   // OK
      return true;  
    }
  }
  return proceed;
}

// --------------------------------------------
//            validatePresent
// Validate if something has been entered
// Returns true if so 
// --------------------------------------------

function validatePresent(valfield,   // element to be validated
                         infofield ) // id of element to receive info/error msg
{
  var stat = commonCheck (valfield, infofield, true);
  if (stat != proceed) return stat;

  msg (infofield, "warn", "");  
  return true;
}

// Make sure a valid URL has been entered
function validateUrl(valfield,   // element to be validated
                         infofield ) // id of element to receive info/error msg
{
	
	
	var stat = commonCheck (valfield, infofield, true);
	if (stat != proceed) return stat;

	var regexp = /^http:\/\//
	//alert("\"" + valfield.value + "\"" + regexp.test(valfield.value))
	if (!regexp.test(valfield.value)) {
		valfield.value = "http://" + valfield.value
	}

	regexp = /^http:\/\/\w(\w+:{0,1}\w*@)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%@!\-\/]))?/

	valfield.value = trim(valfield.value)
	
	if (!regexp.test(valfield.value)) {
		msg(infofield, "error", "Not valid")
		setfocus(valfield)
		return false
	}
	return true
}

function validateEmail  (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;
  
  // value of field with whitespace trimmed off
  valfield.value = trim(valfield.value)
  var tfld = valfield.value;  
  var email = /^[_A-Za-z0-9-]+(\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\.[A-Za-z0-9-]+)*(\.[A-Za-z]{2,3})$/;
  if (!email.test(tfld)) {
    msg (infofield, "error", "Not valid");
    setfocus(valfield);
    return false;
  }

  var email2 = /^[A-Za-z][\w.-]+@\w[\w.-]+\.[\w.-]*[A-Za-z][A-Za-z]$/  ;
  if (!email2.test(tfld)) 
    msg (infofield, "warn", "Unusual");
  else
    msg (infofield, "warn", "");
  return true;
}

function validateDates  (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);  // value of field with whitespace trimmed off
  var gen = /^yyyy-mm-dd$/;
  var dateFormat = /^(19|20)\d\d(\-)(0[1-9]|1[012])(\-)(0[1-9]|[12][0-9]|3[01])$/;
  if (!dateFormat.test(tfld)) {
  	if (gen.test(tfld)){
		msg (infofield, "warn", "");
		return true;
	}
	msg (infofield, "error", "Not Valid");
	setfocus(valfield);
	return false;
  }
  else msg (infofield, "warn", "");
  return true;
}
	
  function validateOnSubmit(theform) {
    var elem
    var errs=0
    
    // execute all element validations in reverse order, so focus gets
    // set to the first one in error.
    if (!validateDates  (theform.from, 'inf_from', false)) errs++ 
	if (!validateDates  (theform.to, 'inf_to', false)) errs++ 
    if (!validateEmail  (theform.email, 'inf_email', true)) errs++ 
    if (!validateUrl(theform.url,  'inf_url'))        errs++ 
	if (!validatePresent(theform.fname,  'inf_fname')) errs++ 

    if (errs>1)  alert('Some fields need to be corrected before submitting.');
    if (errs==1) alert('A field needs to be corrected before submitting.');
    
    // Make sure at least 1 repository has been selected
    repos = 0
    if (theform.ia.checked) repos++
    if (theform.google.checked) repos++	
    if (theform.yahoo.checked) repos++
    if (theform.msn.checked) repos++

    if (repos == 0) {
    	alert('You must select at least one repository.')
    	errs++
    }
    
    return (errs==0);
  }