/*
 * This function is used to validate entries on the registration form. It works by determining
 *	what fields are required based on CSS classes. The currently-used classes are as follows:
 *
 *		eventField - This is used when there are multiple events to select from. If there
 *				are any fields with this class, at least one of them must be "checked".
 *				This is independent of the other field types.
 *		requiredField - This is the basic class for text fields. The script will search
 *				through all fields marked as required and raise an error if they are blank.
 *				In addition, it will run the appropriate test on any required field that
 *				also has any of the later classes.
 *		emailField - This ensures that an email address is of the proper name@host.tld format.
 *		phoneField - This ensures that a given phone/fax number is legal to the extent of
 *				containing either seven or ten digits.
 *		zipField - This ensures that a given ZIP code is legal to the extent of containing
 *				either five or nine digits
 *		stateField - This ensures that the given state code is in the list of 50 states plus
 *				district and territories.
 *
 * Note that all the "types" of required fields will not be validated if they are not also
 *	marked as required.
 *
 * If there are any "eventField" fields and none of them are marked, this function will display
 *	an alert to that effect and return false immediately.
 * If one or more of the "requiredField" fields fail their test(s), this function will display
 *	an alert listing each problem with explanatory text based on the field's title attribute
 *	and return false.
 * If everything passes, it will return true.    
 */



function validateFields() {

	// before the normal, or "plebian" fields, we'd better make sure there's at least one event selected
	eventFields = getElementsByClassName("eventField", document);
	if(eventFields.length > 0) {
		anySelected = false;
		for(index = 0; index < eventFields.length; index++) {
			currentElement = eventFields[index];
			if(currentElement.checked) {
				anySelected = true;
				break;
			}
		}
		if(!anySelected) {
			// this is hard-coded for multiple events; maybe later I'll look into changing the wording
			//	based on if it's a radio button set or checkboxes
			alert("Please select at least one event to attend.");
			return false;
		}
	}

	// fetch every field on the form marked as required (of class "requiredField") 
	requiredElements = getElementsByClassName("requiredField", document);
	
	emailClass = new RegExp("\\bemailField\\b");
	phoneClass = new RegExp("\\bphoneField\\b");
	zipClass = new RegExp("\\bzipField\\b");
	stateClass = new RegExp("\\bstateField\\b");
	
	alertText = "";
	for(index = 0; index < requiredElements.length; index++) {
		currentElement = requiredElements[index];
		
		if(trimAll(currentElement.value) == "") {
			alertText += currentElement.title + " field is empty\n";
		} else if(emailClass.test(currentElement.className)) {
			emailReturn = legalEmail(currentElement.value);
			if(emailReturn != "")
				alertText += currentElement.title + emailReturn;
		} else if(phoneClass.test(currentElement.className)) {
			phoneReturn = legalPhone(currentElement.value);
			if(phoneReturn != "")
				alertText += currentElement.title + phoneReturn;
		} else if(zipClass.test(currentElement.className)) {
			zipReturn = legalZIP(currentElement.value);
			if(zipReturn != "")
				alertText += currentElement.title + zipReturn;
		} else if(stateClass.test(currentElement.className)) {
			stateReturn = legalState(currentElement.value);
			if(stateReturn != "")
				alertText += currentElement.title + stateReturn;
		}
	}
	if(alertText != "") {
		alert(alertText);
		return false;
	}
	selectBox = document.forms[0].WhenUpgrade;
	if(selectBox.selectedIndex == 0) {
		alert("Please choose an upgrade plan answer.");
		return false;
	}
	return true;
}


function legalZIP(aZip) {	
	cleanZip = stripNonDigits(aZip);
	if(cleanZip.length != 5 && cleanZip.length != 9)
		return " field is not a valid ZIP code.\n";
	return "";
}
function legalPhone(aNumber) {	
	cleanNumber = stripNonDigits(aNumber);
	if(cleanNumber.length != 10 && cleanNumber.length != 11)
		return " field is not a valid phone number.\n";
	return "";
}
function legalEmail(anAddress) {	
	validationResult = isEmail(anAddress);
	if(validationResult != "")
		return " field is not a valid e-mail address: " + validationResult + "\n";
	return "";
}
function legalState(aState) {
	var STATES = "AL/AK/AZ/AR/CA/CO/CT/DE/DC/FL/GA/GU/HI/IA/ID/IL/IN/IA/KS/KY/LA/ME/MD/MA/MI/MN/MS/MO/MT/NE/NV/NH/NJ/NM/NY/NC/ND/OH/OK/OR/PA/PR/RI/SC/SD/TN/TX/UT/VI/VT/VA/WA/WV/WI/WY";
	var newStr = aState.toUpperCase();
	if(STATES.indexOf(newStr) == -1 || newStr.indexOf("/") != -1 || newStr.length != 2) {
		return " field is not a valid state code.\n";
	}
	return "";
}

// *********************************************************************************** //

// http://www.webxpertz.net/forums/showthread.php?t=30555
//	...except the commenting
function getElementsByClassName(className, container) {
	var arr   = [];
	var reg   = new RegExp("\\b"+className+"\\b");
	container = document.getElementById(container)||container||document;
	var all   = container.all||container.getElementsByTagName("*");

    var elm, k=-1;
    for(index = 0; index < all.length; index++) {
		elm = all[index];
        	if(reg.test(elm.className))
            arr[arr.length]=elm;
    }
    return arr
}

// This is useful for string trimming. This isn't built into JavaScript?
function trimAll(sString) {
	while (sString.substring(0,1) == ' ') {
		sString = sString.substring(1, sString.length);
	}
	while (sString.substring(sString.length-1, sString.length) == ' ') {
		sString = sString.substring(0, sString.length-1);
	}
	return sString;
}
function isNumeric(field) {
	var errCount = 0;
	var numdecs = 0;              // number of decimal points
	var nummins = 0;              // number of minus signs
	for(j = 0; j < field.length; j++) {
		c = field.charAt(j);        // short hand notation for character at position j
		if((c >= 0 && c <= 9) || (c == "." || c == "-")) {
			if(c == ".") numdecs++;     // count the number of decimal points
			if(c == "-") nummins++;     // count the number of minus signs
		} else {
      		errCount++;               // if it's none of those, increment error counter
      	}
    	}
  	// error if count is non-zero or there are more than one decimal point or minus sign
  	if(errCount > 0 || numdecs > 1 || nummins > 1) {
    		return false;
    	}
  	return true;
}
function stripNonDigits(str) {
	newStr = "";
	for(j = 0; j < str.length; j++) {
	    c = str.charAt(j);
	    if(c >= "0" && c <= "9") {
			newStr += c;
		}
 	}
	return newStr;
}

// this is not my code, although I did edit it somewhat for my purposes
function isEmail(emailStr) {
	var checkTLD = 1;
	var knownDomsPat = /^(com|COM|net|NET|org|ORG|edu|EDU|int|mil|MIL|gov|GOV|arpa|biz|aero|name|coop|info|pro|museum|tv)$/;
	var emailPat = /^(.+)@(.+)$/;
	var specialChars = "\\(\\)><@,;:\\\\\\\"\\.\\[\\]";
	var validChars = "\[^\\s" + specialChars + "\]";
	var quotedUser = "(\"[^\"]*\")";
	var ipDomainPat = /^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;
	var atom = validChars + '+';
	var word = "(" + atom + "|" + quotedUser + ")";
	var userPat = new RegExp("^" + word + "(\\." + word + ")*$");
	var domainPat = new RegExp("^" + atom + "(\\." + atom +")*$");

	var matchArray=emailStr.match(emailPat);

	if(matchArray == null)
		return "check @ and .'s";
	var user = matchArray[1];
	var domain = matchArray[2];

	for(i = 0; i < user.length; i++) {
		if (user.charCodeAt(i) > 127)
			return "invalid characters in the user name";
	}
	for(i = 0; i < domain.length; i++) {
		if (domain.charCodeAt(i) > 127)
			return "invalid characters in the domain name";
	}

	if(user.match(userPat) == null)
		return "user name appears to be invalid";

	var IPArray = domain.match(ipDomainPat);
	if(IPArray != null) {
		for (var i = 1; i <= 4; i++) {
			if (IPArray[i] > 255)
				return "IP address is invalid";
		}
	}
 
	var atomPat = new RegExp("^" + atom + "$");
	var domArr = domain.split(".");
	var len = domArr.length;
	for(i = 0; i < len; i++) {
		if (domArr[i].search(atomPat) == -1)
			return "domain name appears to be invalid";
	}

	if(checkTLD && domArr[domArr.length-1].length != 2 && 
	   domArr[domArr.length-1].search(knownDomsPat) == -1)
		return "need a well-known domain or two letter country code";

	if(len < 2)
		return "missing host name";

	return "";
}


// this is not my code, although I did edit it somewhat for my purposes
function isEmail(emailStr) {
	var checkTLD = 1;
	var knownDomsPat = /^(com|COM|net|NET|org|ORG|edu|EDU|int|mil|MIL|gov|GOV|arpa|biz|aero|name|coop|info|pro|museum|tv)$/;
	var emailPat = /^(.+)@(.+)$/;
	var specialChars = "\\(\\)><@,;:\\\\\\\"\\.\\[\\]";
	var validChars = "\[^\\s" + specialChars + "\]";
	var quotedUser = "(\"[^\"]*\")";
	var ipDomainPat = /^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;
	var atom = validChars + '+';
	var word = "(" + atom + "|" + quotedUser + ")";
	var userPat = new RegExp("^" + word + "(\\." + word + ")*$");
	var domainPat = new RegExp("^" + atom + "(\\." + atom +")*$");

	var matchArray=emailStr.match(emailPat);

	if(matchArray == null)
		return "check @ and .'s";
	var user = matchArray[1];
	var domain = matchArray[2];

	for(i = 0; i < user.length; i++) {
		if (user.charCodeAt(i) > 127)
			return "invalid characters in the user name";
	}
	for(i = 0; i < domain.length; i++) {
		if (domain.charCodeAt(i) > 127)
			return "invalid characters in the domain name";
	}

	if(user.match(userPat) == null)
		return "user name appears to be invalid";

	var IPArray = domain.match(ipDomainPat);
	if(IPArray != null) {
		for (var i = 1; i <= 4; i++) {
			if (IPArray[i] > 255)
				return "IP address is invalid";
		}
	}
 
	var atomPat = new RegExp("^" + atom + "$");
	var domArr = domain.split(".");
	var len = domArr.length;
	for(i = 0; i < len; i++) {
		if (domArr[i].search(atomPat) == -1)
			return "domain name appears to be invalid";
	}

	if(checkTLD && domArr[domArr.length-1].length != 2 && 
	   domArr[domArr.length-1].search(knownDomsPat) == -1)
		return "need a well-known domain or two letter country code";

	if(len < 2)
		return "missing host name";

	return "";
}