window.onload = initialise;

function initialise()
{
var objForms = document.getElementsByTagName('form');

// Attach an event handler for each form
for (var iCounter=0; iCounter<objForms.length; iCounter++)
objForms[iCounter].onsubmit= function(){return validateForm(this);}
}


// Event handler for the form
function validateForm(objForm)
{
var arClass = new Array();
var iErrors = 0;
var objField = objForm.getElementsByTagName('input');
var objSelect = objForm.getElementsByTagName('select');
var objLabel = objForm.getElementsByTagName('label');
var objList = document.createElement('ol');

// Get the id or name of the form, to make a unique
// fragment identifier
if (objForm.id)
var strLinkID = objForm.id + 'ErrorID';
else
var strLinkID = objForm.name + 'ErrorID';

// Iterate through input form controls, looking for validation classes
for (var iFieldCounter=0; iFieldCounter<objField.length; iFieldCounter++)
{
// Get the class for the field, and look for the appropriate class
arClass = objField[iFieldCounter].className.split(' ');
for (var iClassCounter=0; iClassCounter<arClass.length; iClassCounter++)
{
switch (arClass[iClassCounter])
{
case 'string':
if (!isString(objField[iFieldCounter].value, arClass))
{
if (iErrors == 0)
logError(objField[iFieldCounter], objLabel, objList, strLinkID);
else
logError(objField[iFieldCounter], objLabel, objList, '');
iErrors++;
}
break;
case 'number':
if (!isNumber(objField[iFieldCounter].value, arClass))
{
if (iErrors == 0)
logError(objField[iFieldCounter], objLabel, objList, strLinkID);
else
logError(objField[iFieldCounter], objLabel, objList, '');
iErrors++;
}
break;
case 'phone':
if (!isPhone(objField[iFieldCounter].value, arClass))
{
if (iErrors == 0)
logError(objField[iFieldCounter], objLabel, objList, strLinkID);
else
logError(objField[iFieldCounter], objLabel, objList, '');
iErrors++;
}
break;
case 'email' :
if (!isEmail(objField[iFieldCounter].value, arClass))
{
if (iErrors == 0)
logError(objField[iFieldCounter], objLabel, objList, strLinkID);
else
logError(objField[iFieldCounter], objLabel, objList, '');
iErrors++;
}
break;
}
}
}

// Iterate through input form controls, looking for validation classes
for (var iFieldCounter=0; iFieldCounter<objSelect.length; iFieldCounter++)
{
// Get the class for the field, and look for the appropriate class
arClass = objSelect[iFieldCounter].className.split(' ');
for (var iClassCounter=0; iClassCounter<arClass.length; iClassCounter++)
{
switch (arClass[iClassCounter])
{
case 'string':
if (!isString(objSelect[iFieldCounter].value, arClass))
{
if (iErrors == 0)
logError(objSelect[iFieldCounter], objLabel, objList, strLinkID);
else
logError(objSelect[iFieldCounter], objLabel, objList, '');
iErrors++;
}
break;
case 'number':
if (!isNumber(objSelect[iFieldCounter].value, arClass))
{
if (iErrors == 0)
logError(objSelect[iFieldCounter], objLabel, objList, strLinkID);
else
logError(objSelect[iFieldCounter], objLabel, objList, '');
iErrors++;
}
break;
case 'phone':
if (!isPhone(objSelect[iFieldCounter].value, arClass))
{
if (iErrors == 0)
logError(objSelect[iFieldCounter], objLabel, objList, strLinkID);
else
logError(objSelect[iFieldCounter], objLabel, objList, '');
iErrors++;
}
break;
case 'email' :
if (!isEmail(objSelect[iFieldCounter].value, arClass))
{
if (iErrors == 0)
logError(objSelect[iFieldCounter], objLabel, objList, strLinkID);
else
logError(objSelect[iFieldCounter], objLabel, objList, '');
iErrors++;
}
break;
}
}
}

if (iErrors > 0)
{
// If not valid, display error messages
var objError = objForm.getElementsByTagName('div');

// Look for existing errors
for (var iCounter=0; iCounter<objError.length; iCounter++)
if (objError[iCounter].className == 'validationerrors')
var objExisting = objError[iCounter];

var objNew = document.createElement('div');
var objTitle = document.createElement('h3');
var objParagraph = document.createElement('p');
var objAnchor = document.createElement('a');

if (iErrors == 1)
objAnchor.appendChild(document.createTextNode('Error in form fields'));
else
objAnchor.appendChild(document.createTextNode('Errors in form fields'));
objAnchor.href = '#' + strLinkID;
objAnchor.className = 'submissionerror';

objTitle.appendChild(objAnchor);
objParagraph.appendChild(document.createTextNode('Please review and correct the following errors:'));
objNew.className = 'validationerrors';

objNew.appendChild(objTitle);
objNew.appendChild(objParagraph);
objNew.appendChild(objList);

// If there were existing error, replace them with the new lot,
// otherwise add the new errors to the start of the form
if (objExisting)
objExisting.parentNode.replaceChild(objNew, objExisting);
else
{
var objPosition = objForm.firstChild;
objForm.insertBefore(objNew, objPosition);
}

objAnchor.focus();

// Don't submit the form
objForm.submitAllowed = false;
return false;
} else if(objForm.id == "form-resources" || objForm.id == "form-landing" || objForm.id == "form-campaign") {
// Add link and submit the form
addDownloadLinks();
return true;
}

// Submit the form
return true;
}

// Function to add a link in a list item that points to problematic field control
function addError(objList, strError, strID, strErrorID)
{
var objListItem = document.createElement('li');
var objAnchor = document.createElement('a');

// Fragment identifier to the form control
objAnchor.href='#' + strID;

// Make this the target for the error heading
if (strErrorID.length > 0)
objAnchor.id = strErrorID;

// Use the label prompt for the error message
objAnchor.appendChild(document.createTextNode(strError));
// Add keyboard and mouse events to set focus to the form control
objAnchor.onclick = function(event){return focusFormField(this, event);}
objAnchor.onkeypress = function(event){return focusFormField(this, event);}
objListItem.appendChild(objAnchor);
objList.appendChild(objListItem);
}

function focusFormField(objAnchor, objEvent)
{
// Allow keyboard navigation over links
if (objEvent && objEvent.type == 'keypress')
if (objEvent.keyCode != 13 && objEvent.keyCode != 32)
return true;

// set focus to the form control
var strFormField = objAnchor.href.match(/[^#]\w*$/);
var objForm = getForm(strFormField);
objForm[strFormField].focus();
return false;
}

// Function to return the form element from a given form field name
function getForm(strField)
{
var objElement = document.getElementById(strField);

// Find the appropriate form
do
{
objElement = objElement.parentNode;
} while (!objElement.tagName.match(/form/i) && objElement.parentNode);

return objElement;
}

// Function to log the error in a list
function logError(objField, objLabel, objList, strErrorID)
{
// Search the label for the error prompt
for (var iCounter=0; iCounter<objLabel.length; iCounter++)
if (objLabel[iCounter].htmlFor == objField.id)
var strError = objLabel[iCounter].firstChild.nodeValue;

addError(objList, strError, objField.id, strErrorID);
}

// Validation routines - add as required

function isString(strValue, arClass)
{
var bValid = (typeof strValue == 'string' && strValue.replace(/^\s*|\s*$/g, '') != '' && isNaN(strValue));

return checkOptional(bValid, strValue, arClass);
}

function isEmail(strValue, arClass)
{
var objRE = /^[\w-\.\']{1,}\@([\da-zA-Z-]{1,}\.){1,}[\da-zA-Z-]{2,}$/;
var bValid = objRE.test(strValue);

return checkOptional(bValid, strValue, arClass);
}

function isNumber(strValue, arClass)
{
var bValid = (!isNaN(strValue) && strValue.replace(/^\s*|\s*$/g, '') != '');

return checkOptional(bValid, strValue, arClass);
}

function isPhone(strValue, arClass)
{
var objRE = /^[-+\(\)\d\s]*$/;
var bValid = (objRE.test(strValue) && strValue.replace(/^\s*|\s*$/g, '') != '');

return checkOptional(bValid, strValue, arClass);
}

function checkOptional(bValid, strValue, arClass)
{
var bOptional = false;

// Check if optional
for (var iCounter=0; iCounter<arClass.length; iCounter++)
if (arClass[iCounter] == 'optional')
bOptional = true;

if (bOptional && strValue.replace(/^\s*|\s*$/g, '') == '')
return true;

return bValid;
}