/*
 * Class to check all items of an HTMLForms form.
 *
 */
var htmlFormsValidation = new function HTMLFormsValidation() {

	var formValid;
	var focusNode;
	var errorSpanIdExtension = '_error';



	/* Checks all items defined before.
	 *
	 * Accepts:	formItems	An array of HTMLFormsItem objects to validate.
	 *
	 * Returns:	boolean
	 *
	 */
	this.checkForm = function(formItems) {

		var formItem;
		var formItemNode;
		var formItemErrorNode;

		// At the moment everything is fine...
		formValid = true;
		focusNode = null;

		// Check if we can validate the input using DOM.
		// If not possible, give up and let server validate.
		if (!document.getElementById) {
			return true;
		}

		// Remove all previous error messages
		for (var i = 0; i < formItems.length; i++) {

			formItem = formItems[i];

			// Get some nodes
			formItemNode = document.getElementById(formItem.id);
			formItemErrorNode = document.getElementById(formItem.id + errorSpanIdExtension);

			// Remove error msgs
			if (formItemErrorNode) {
				formItemErrorNode.innerHTML = '';
			}

			// If no error node exists, add one
			else if (formItemNode) {
				var node = document.createElement('span');
				node.setAttribute('id', formItem.id + errorSpanIdExtension);
				formItemNode.parentNode.appendChild(node);
			}

		}

		// Validate all form items
		for (var i = 0; i < formItems.length; i++) {

			formItem = formItems[i];

			// Go to next item if validation not required
			if (!formItem.required) {
				continue;
			}

			// Get the items' node
			formItemNode = document.getElementById(formItem.id);

			// Check item
			switch (formItem.type){

				// Text input field
				case 'text':
					if (formItemNode == null || formItemNode.value == '') {
						handleHtmlFormError(formItem.id, formItem.msg);
					}
					break;

				// Email
				case 'email':
					if (formItemNode == null || formItemNode.value == '') {
						handleHtmlFormError(formItem.id, formItem.msg);
					} else {

						var emailRegExpr = /^[\w-\+]+(?:\.[\w-\+]+)*@(?:[\w-\+]+\.)+[a-zA-Z]{2,7}$/;
                        if (!emailRegExpr.test(formItemNode.value)) {
                            handleHtmlFormError(formItem.id, formItem.msg);
                        }

					}

					break;

				// Textarea
				case 'textarea':
					if (formItemNode == null || formItemNode.value == '') {
						handleHtmlFormError(formItem.id, formItem.msg);
					}
                    if (formItem.maxLength && formItemNode && formItemNode.value.length > formItem.maxLength) {
                        handleHtmlFormError(formItem.id, 'You are over the maximum length of ' +
                                            formItem.maxLength + ' characters. (' + formItemNode.value.length + ')' );
                    }
					break;

               

				// Dropdown
				case 'dropdown':
					if (formItemNode.selectedIndex == null || formItemNode.selectedIndex == -1 || formItemNode.options[formItemNode.selectedIndex].value == null || formItemNode.options[formItemNode.selectedIndex].value == '') {
						handleHtmlFormError(formItem.id, formItem.msg);
					}
					break;

                                // Country
                                case 'country':
                                        if (formItemNode.selectedIndex == null || formItemNode.selectedIndex == -1 || formItemNode.options[formItemNode.selectedIndex].value == null || formItemNode.options[formItemNode.selectedIndex].value == '') {
                                                handleHtmlFormError(formItem.id, formItem.msg);
                                        }
                                        break;

				// Radio butttons
				case 'radio':

					// Get all nodes with this items' name
					var formItemName = formItemNode.getAttribute('name');
					var formItemNameNodes = document.getElementsByName(formItemName);
					var formItemCommonParent = formItemNode.parentNode;

					// Validate whether at least one of these nodes is checked
					var itemSelected = false;
					for (j = 0; j < formItemNameNodes.length; j++) {
						if (formItemNameNodes[j].nodeName == 'INPUT' && formItemNameNodes[j].getAttribute('type') == 'radio' && formItemNameNodes[j].parentNode == formItemCommonParent && formItemNameNodes[j].checked) {
							itemSelected = true;
						}
					}
					if (!itemSelected) {
						handleHtmlFormError(formItem.id, formItem.msg);
					}
					break;

				// Checkbox
				case 'checkbox':

					// Get all nodes with this items' name
					var formItemName = formItemNode.getAttribute('name');
					var formItemNameNodes = document.getElementsByName(formItemName);
					var formItemCommonParent = formItemNode.parentNode;

					// Validate whether at least one of these nodes is checked
					var itemSelected = false;
					for (j = 0; j < formItemNameNodes.length; j++) {
						if (formItemNameNodes[j].nodeName == 'INPUT' && formItemNameNodes[j].getAttribute('type') == 'checkbox' && formItemNameNodes[j].parentNode == formItemCommonParent && formItemNameNodes[j].checked) {
							itemSelected = true;
						}
					}
					if (!itemSelected) {
						handleHtmlFormError(formItem.id, formItem.msg);
					}
					break;

			}
		}

		// Set focus to first invalid item
		if (focusNode != null) {
			focusNode.focus();
		}

		// Return entire form status
		return formValid;
	}



	/* Handles an error.
	 *
	 * Accepts:	string	id		DOM-ID of item that causes the error
	 *		string	msg		Error message to display
	 *
	 * Returns:	-
	 *
	 */
	function handleHtmlFormError (id, msg) {

		var formItemNode = document.getElementById(id);
		var formItemErrorNode = document.getElementById(id + errorSpanIdExtension);

		formValid = false;

		// Mark current node as focus node if there was none before
		if (focusNode == null ) {
			focusNode = formItemNode;
		}

		// Display error
		if (formItemErrorNode) {
			document.getElementById(id + errorSpanIdExtension).innerHTML = '<br />' + msg;
			document.getElementById(id + errorSpanIdExtension).style.color = '#FF0000';
		} else {
			alert(msg);
		}
	}

}


/*
 * Class to generate form items.
 *
 */
function HtmlFormsItem(id, type, msg, required, maxLength) {
	this.id			= id;
	this.type		= type;
	this.msg		= msg;
    this.maxLength  = maxLength;

	if (required == null || (String(required) != 'true' && String(required) != 'false')) {
		this.required = true;
	} else {
		this.required = required;
	}
}