// Javascript form validation
//
// Usage
//
// <SCRIPT LANGUAGE="JavaScript" SRC="validate.js"></SCRIPT>
// <SCRIPT LANGUAGE="JavaScript">
// 
// function checkWholeForm(theForm) {
//     var why = "";
//     why += checkEmail(theForm.email.value);
//     why += checkPhone(theForm.phone.value);
//     why += checkPassword(theForm.password.value);
//     why += checkUsername(theForm.username.value);
//     why += isEmpty(theForm.notempty.value, FieldName);
//     why += isDifferent(theForm.different.value);
//     for (i=0, n=theForm.radios.length; i<n; i++) {
//         if (theForm.radios[i].checked) {
//             var checkvalue = theForm.radios[i].value;
//             break;
//         } 
//     }
//     why += checkRadio(checkvalue);
//     why += checkDropdown(theForm.choose.selectedIndex, FieldName);
//     if (why != "") {
//        alert(why);
//        return false;
//     }
// return true;
// }
// 
// </SCRIPT>
//
// <FORM NAME="theForm" onSubmit="javascript:return checkWholeForm(this);">


// email

function checkEmail (strng) {
var error="";
if (strng == "") {
   error = "You didn't enter an email address.\n";
}

    var emailFilter=/^.+@.+\..{2,3}$/;
    if (!(emailFilter.test(strng))) { 
       error = "Please enter a valid email address.\n";
    }
    else {
//test email for illegal characters
       var illegalChars= /[\(\)\<\>\,\;\:\\\"\[\]]/
         if (strng.match(illegalChars)) {
          error = "The email address contains illegal characters.\n";
       }
    }
return error;    
}


// phone number - strip out delimiters and check for 10 digits

function checkPhone (strng) {
var error = "";
if (strng == "") {
   error = "You didn't enter a phone number.\n";
}

var stripped = strng.replace(/[\(\)\.\-\ ]/g, ''); //strip out acceptable non-numeric characters
    if (isNaN(parseInt(stripped))) {
       error = "The phone number contains illegal characters.";
  
    }
    if (!(stripped.length == 10)) {
	error = "The phone number is the wrong length. Make sure you included an area code.\n";
    } 
return error;
}


// password - between 6-8 chars, uppercase, lowercase, and numeral

function checkPassword (strng) {
var error = "";
if (strng == "") {
   error = "You didn't enter a password.\n";
}

    var illegalChars = /[\W_]/; // allow only letters and numbers
    
    if ((strng.length < 6) || (strng.length > 8)) {
       error = "The password is the wrong length.\n";
    }
    else if (illegalChars.test(strng)) {
      error = "The password contains illegal characters.\n";
    } 
    else if (!((strng.search(/(a-z)+/)) && (strng.search(/(A-Z)+/)) && (strng.search(/(0-9)+/)))) {
       error = "The password must contain at least one uppercase letter, one lowercase letter, and one numeral.\n";
    }  
return error;    
}    


// username - 4-10 chars, uc, lc, and underscore only.

function checkUsername (strng) {
var error = "";
if (strng == "") {
   error = "You didn't enter a username.\n";
}


    var illegalChars = /\W/; // allow letters, numbers, and underscores
    if ((strng.length < 4) || (strng.length > 10)) {
       error = "The username is the wrong length.\n";
    }
    else if (illegalChars.test(strng)) {
    error = "The username contains illegal characters.\n";
    } 
return error;
}       


// non-empty textbox

function isEmpty(strng, fldName) {
var error = "";
  if (strng.length == 0) {
     error = "The " + fldName + " field has not been filled in.\n"
  }
return error;	  
}

// was textbox altered

function isDifferent(strng) {
var error = ""; 
  if (strng != "Can\'t touch this!") {
     error = "You altered the inviolate text area.\n";
  }
return error;
}

// exactly one radio button is chosen

function checkRadio(checkvalue) {
var error = "";
   if (!(checkvalue)) {
       error = "Please check a radio button.\n";
    }
return error;
}

// valid selector from dropdown list

function checkDropdown(choice, fldName) {
var error = "";
    if (choice == 0) {
    error = "You didn't choose an option from the " + fldName + " drop-down list.\n";
    }    
return error;
}    


