var dates = new Array;
var dateassociations = new Array;
var datecount = 1;
function checkrequired(event) {
	// Checks that required fields are filled in.
	// Required fields are those with class="required"
	if(event) {
		if(event.srcElement) {
			var formobj = event.srcElement;
		} else {
			var formobj = event.target;
		}
	} else {
		var formobj = this;
	}

	var error = checkrequirednode(formobj);
	// Check date fields
	for(var count = 1; count < datecount; count++) {
		if(dates[count]['day'] != '' || dates[count]['month'] != '' || dates[count]['year'] != '') {
			var name = dates[count]['prefix'];
			if(dates[count]['id'] != '') {
				var labels = document.getElementsByTagName('label');
				for(var labelcount = 0; labelcount < labels.length; labelcount++) {
					var label = labels[labelcount];
					if(label.htmlFor == dates[count]['id']) {
						name = gettextcontents(label);
					}
				}
			}
			if(dates[count]['day'] == '' || dates[count]['month'] == '' || dates[count]['year'] == '') {
				// Incomplete date. Error.
				error += '• Date in "'+name+'" is incomplete.\n';
			} else {
				// Check date validity
				var valid = true;
				var day = dates[count]['day'];
				var month = dates[count]['month'];
				var year = dates[count]['year'];
				var pattern = /^[0-9]{1,2}$/;
				if(!pattern.test(day)) {
					error += '• Day in "'+name+'" is invalid.\n';
					valid = false;
				}
				var pattern = /^[0-9]{1,2}$/;
				if(!pattern.test(month)) {
					error += '• Month in "'+name+'" is invalid.\n';
					valid = false;
				}
				var pattern = /^([0-9]{1,2}|[0-9]{4})$/;
				if(!pattern.test(year)) {
					error += '• Year in "'+name+'" is invalid.\n';
					valid = false;
				}
				if(valid) {
					if(year.length == 1) year = '200' + year;
					if(year.length == 2) year = '20' + year;
					day = parseInt(day, 10);
					month = parseInt(month, 10);
					year = parseInt(year, 10);
					if(year < 1970) {
						error += '• Year in "'+name+'" is too low.\n';
						valid = false;
					}
					if(valid) {
						if(month < 1) {
							error += '• Month in "'+name+'" is too low.\n';
							valid = false;
						} else if(month > 12) {
							error += '• Month in "'+name+'" is too high.\n';
							valid = false;
						} else if(month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) {
							var daysinmonth = 31;
						} else if(month == 2) {
							if(year % 4 == 0 && (year % 10 != 0 || year % 100 == 0)) { 
								var daysinmonth = 29;
							} else {
								var daysinmonth = 28;
							}
						} else { 
							var daysinmonth = 30;
						}
						if(valid) {
							if(day < 1) {
								error += '• Day in "'+name+'" is too low.\n';
								valid = false;
							} else if(day > daysinmonth) {
								error += '• Day in "'+name+'" is too high.\n';
								valid = false;
							}
						}
					}
				}
			}
		} else {
			// Empty. Nothing needs to be done here (if this is a required field it is dealt with in the
			// required field check).
		}
	}
	if(error != '') {
		alert('Unable to proceed:\n'+error);
		if(event.target) {
			event.preventDefault();
		}
		return false;
	} else {
		return true;
	}
}
function checkrequirednode(obj) {
	var error = '';
	for(var count = 0; count < obj.childNodes.length; count++) {
		var node = obj.childNodes[count];
		var tag = new String(node.tagName);
		tag = tag.toLowerCase();
		if((tag == 'input' || tag == 'select' || tag == 'textarea') && node.disabled == false) {
			var objclasses = ' ' + node.className + ' ';
			// Check required fields
			if(objclasses.indexOf(' required ') != -1) {
				if(node.value == '') {
					error += '• Required field "'+getnodename(node)+'" not filled in.\n';
				}
			}
			// Check numeric fields
			if(objclasses.indexOf(' numeric ') != -1 && node.value.length > 0) {
				var pattern = /^\-?[0-9,]*\.?[0-9,]*$/;
				if(!pattern.test(node.value)) {
					error += '• Field "'+getnodename(node)+'" must be a number.\n';
				}
			}
			// Check password fields
			if(objclasses.indexOf(' password ') != -1 && node.value.length > 0) {
				if(node.value.length > 0 && node.value.length < 5) {
					error += '• Field "'+getnodename(node)+'" must be at least 5 characters long.\n';
				}
			}
			// Check e-mail fields.
			// 02 March 09. Made case insensitive by adding i at the end of 'pattern'
			if(objclasses.indexOf(' email ') != -1 && node.value.length > 0) {
				var pattern = /^[^ @]+@[a-z0-9\-\.]+\.[a-z0-9]+$/i
				if(!pattern.test(node.value)) {
					error += '• Field "'+getnodename(node)+'" must be a valid e-mail address.\n';
				}
			}
			// Check creditcard numbers
			if(objclasses.indexOf(' creditcard ') != -1 && node.value.length > 0) {
				var number = new String(node.value);
				number = number.replace(/[^0-9]*/g, '');
				var numlen = number.length;
				var sum = 0;
				for(var charno = numlen - 2; charno >= 0; charno -= 2) {
					var value = parseInt(number.substr(charno, 1), 10) * 2;
					if(value > 9) {
						value = Math.floor(value / 10) + (value % 10);
					}
					sum += value;
				}
				for(charno = numlen - 1; charno >= 0; charno -= 2) {
					sum += parseInt(number.substr(charno, 1), 10);
				}
				if(!(sum % 10 == 0)) error += '• "'+getnodename(node)+'" does not appear to be a valid card number.\n';
			}
			// Get date fields into array
			if(objclasses.indexOf(' date ') != -1) {
				if(node.name.indexOf('day') == node.name.length - 3) {
					var prefix = node.name.substr(0, node.name.length - 3);
					if(dateassociations[prefix]) {
						var number = dateassociations[prefix];
					} else {
						var number = datecount;
						dateassociations[prefix] = number;
						//alert('1: '+node.name+' '+prefix+' '+dateassociations[prefix]);
						dates[number] = new Array;
						datecount++;
					}
					dates[number]['day'] = node.value;
					dates[number]['id'] = node.id;
					dates[number]['prefix'] = prefix;
				}
				if(node.name.indexOf('month') == node.name.length - 5) {
					var prefix = node.name.substr(0, node.name.length - 5);
					if(dateassociations[prefix]) {
						var number = dateassociations[prefix];
					} else {
						var number = datecount;
						dateassociations[prefix] = number;
						//alert('2: '+node.name+' '+prefix+' '+dateassociations[prefix]);
						dates[number] = new Array;
						datecount++;
					}
					dates[number]['month'] = node.value;
				}
				if(node.name.indexOf('year') == node.name.length - 4) {
					var prefix = node.name.substr(0, node.name.length - 4);
					if(dateassociations[prefix]) {
						var number = dateassociations[prefix];
					} else {
						var number = datecount;
						dateassociations[prefix] = number;
						//alert('3: '+node.name+' '+prefix+' '+dateassociations[prefix]);
						dates[number] = new Array;
						datecount++;
					}
					dates[number]['year'] = node.value;
				}
			}
		} else {
			// Check all child nodes
			error += checkrequirednode(node);
		}
	}
	return error;
}
function getnodename(node) {
	var name = node.name;
	if(node.id != '') {
		var labels = document.getElementsByTagName('label');
		for(var labelcount = 0; labelcount < labels.length; labelcount++) {
			var label = labels[labelcount];
			if(label.htmlFor == node.id) {
				name = gettextcontents(label);
			}
		}
	}
	return name;
}
function gettextcontents(node) {
	var textcontents = '';
	for(var childcount = 0; childcount < node.childNodes.length; childcount++) {
		if(node.childNodes[childcount].nodeType == 3) {
			// TEXT_NODE
			textcontents += node.childNodes[childcount].data;
		} else {
			textcontents += gettextcontents(node.childNodes[childcount]);
		}
	}
	return textcontents;
}

// Add onsubmit handlers to any <form>s
addevent(window, "load", addformchecks);
function addformchecks() {
	var forms = document.getElementsByTagName('form');
	for(var count = 0; count < forms.length; count++) {
		var form = forms[count];
		addevent(form, "submit", checkrequired);
	}
}

function addevent(elm, evType, fn, useCapture)
// cross-browser event handling for IE5+,  NS6 and Mozilla
// By Scott Andrew
{
	if(elm.attachEvent) {
		var r = elm.attachEvent("on"+evType, fn);
		return r;
	} else if(elm.addEventListener) {
		elm.addEventListener(evType, fn, useCapture);
		return true;
	} else {
		//alert("Handler could not be removed");
	}
} 

function checkcatno(catnocontent) {
	// This wee js snippet will verify the new catalogue number according to rules shown below
	// It already arrives here in all uppercase, so no need to do that again
	// 1) Must start with a letter
	// 2) Must contain at least 1 numbers
	// 3) Can only contain letters, numbers, - and /
	// 4) Cannot contain whitespace
	var minimumnumbers = 1; // used in this function a few times. Tried to use
	// const but IE doesn't support it :-/ Anyway it doesn't change.

	// loop through the string checking a few things
	if (catnocontent.length > 0) {
		var numberscount = 0;
		var illegalcharacter = false;
		var firstCharIsLetter = false;
		var whitespace  =false;
					
    	for (var i=0; i < catnocontent.length ; i++){     		
			currentchar = catnocontent.charAt(i);
			
				// check for letter at first char
				if(i==0) {
					if(/[A-Z]/.test(currentchar)) firstCharIsLetter = true;
				}
				// count number of numbers, not looking at first char
				if(i>0) {
					if(/[0-9]/.test(currentchar)){
						numberscount += 1;
                    }
				}
				// reject all other characters except - and /
                if(!(/[A-Z0-9/-]/.test(currentchar))){
                   illegalcharacter = currentchar;
                }

                // finally test for whitespace
                if((/\s+/.test(currentchar))){
                    whitespace = true;
                 }                 
        }
    }
	
	if( (firstCharIsLetter == true) && (numberscount > (minimumnumbers-1)) && (illegalcharacter == false) && (whitespace == false)) { // well formed
		return true; // will be true
	}
	else {
		var alertstring = 'Use the guidelines for CatNo./WebRef No.\n';
		if(firstCharIsLetter != true) alertstring += '\tStarts with a letter\n';
		if(numberscount < minimumnumbers) alertstring += '\tContains at least '+minimumnumbers+' numbers\n';
		if(illegalcharacter != false) alertstring += '\tUses only letters, numbers, - and /\n';
		if(whitespace != false) alertstring += '\tUses no whitespace (spaces or tabs)';
		alert(alertstring);
	}		
	return false;
}