//////////////////////////////////////////////////////
//  AJAX Functions
//  http://www.phpbuilder.com/columns/kassemi20050613.php3 and http://developer.apple.com/internet/webcontent/xmlhttpreq.html
//
//  These ajax functions are only used in problemDatabase searching to show a preview of the problem
//
//////////////////////////////////////////////////////

/* The following function creates an XMLHttpRequest object... */

function createRequestObject(){
        var request_o; //declare the variable to hold the object.
        var browser = navigator.appName; //find the browser name
        if(browser == "Microsoft Internet Explorer"){
                /* Create the object using MSIE's method */
                request_o = new ActiveXObject("Microsoft.XMLHTTP");
        }else{
                /* Create the object using other browser's method */
                request_o = new XMLHttpRequest();
        }
        return request_o; //return the object
}

/* The variable http will hold our new XMLHttpRequest object. */
var http = createRequestObject(); 

/* Function called to get the product categories list */
function getProblemDetail(id){
        /* Create the request. The first argument to the open function is the method (POST/GET),
                and the second argument is the url... 
                document contains references to all items on the page
                We can reference document.form_category_select.select_category_select and we will               
                be referencing the dropdown list. The selectedIndex property will give us the 
                index of the selected item. 
        */
        http.open('get', 'ajaxResponse.php?problemActionType=getProblemDetail&id=' + id);
        /* Define a function to call once a response has been received. This will be our
                handleProductCategories function that we define below. */
        http.onreadystatechange = displayProblemDetail; 
        /* Send the data. We use something other than null when we are sending using the POST
                method. */
        http.send(null);
}

/* Function called to handle the list that was returned from the internal_request.php file.. */
function displayProblemDetail(){
        /* Make sure that the transaction has finished. The XMLHttpRequest object 
                has a property called readyState with several states:
                0: Uninitialized
                1: Loading
                2: Loaded
                3: Interactive
                4: Finished */
        if(http.readyState == 4){ //Finished loading the response
                /* We have got the response from the server-side script,
                        let's see just what it was. using the responseText property of 
                        the XMLHttpRequest object. */
                var response = http.responseText;
                /* And now we want to change the product_categories <div> content.
                        we do this using an ability to get/change the content of a page element 
                        that we can find: innerHTML. */
                document.getElementById('problemDetail').innerHTML = response;
        }
}










//////////////////////////////////////////////////////
//  This function is called in the body tag.
//  http://www.alistapart.com/articles/zebratables/
//////////////////////////////////////////////////////

  // this function is need to work around 
  // a bug in IE related to element attributes
  function hasClass(obj) {
     var result = false;
     if (obj.getAttributeNode("class") != null) {
         result = obj.getAttributeNode("class").value;
     }
     return result;
  }   

 function stripe(id) {

    // the flag we'll use to keep track of 
    // whether the current row is odd or even
    var even = false;
  
    // if arguments are provided to specify the colours
    // of the even & odd rows, then use the them;
    // otherwise use the following defaults:
    var evenColor = arguments[1] ? arguments[1] : "#fff";
    var oddColor = arguments[2] ? arguments[2] : "#eee";
  
    // obtain a reference to the desired table
    // if no such table exists, abort
    var table = document.getElementById(id);
    if (! table) { return; }
    
    // by definition, tables can have more than one tbody
    // element, so we'll have to get the list of child
    // &lt;tbody&gt;s 
    var tbodies = table.getElementsByTagName("tbody");

    // and iterate through them...
    for (var h = 0; h < tbodies.length; h++) {
    
     // find all the &lt;tr&gt; elements... 
      var trs = tbodies[h].getElementsByTagName("tr");
      
      // ... and iterate through them
      for (var i = 0; i < trs.length; i++) {

	    // avoid rows that have a class attribute
        // or backgroundColor style
	    if (!hasClass(trs[i]) && ! trs[i].style.backgroundColor) {
 
         // get all the cells in this row...
          var tds = trs[i].getElementsByTagName("td");
        
          // and iterate through them...
          for (var j = 0; j < tds.length; j++) {
        
            var mytd = tds[j];

            // avoid cells that have a class attribute
            // or backgroundColor style
	        if (! hasClass(mytd) && ! mytd.style.backgroundColor) {
        
		      mytd.style.backgroundColor = even ? evenColor : oddColor;
              
            }
          }
        }
        // flip from odd to even, or vice-versa
        even =  ! even;
      }
    }
  }
  
  
  
  
  
  
  
  
  
  

//////////////////////////////////////////////////////
//  These functions are used to validate webforms
//  http://developer.apple.com/internet/webcontent/validation.html
//////////////////////////////////////////////////////

/*

A master function, called checkWholeForm() is placed at the top of the page that contains a form.
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);
    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);
    if (why != "") {
       alert(why);
       return false;
    }
return true;
}

*/


// 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,fieldName) {
var error = "";
  if (strng.length == 0) {
     error = "Please fill in required field:\n " + fieldName + "\n\n\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,fieldName) {
var error = "";
   if (!(checkvalue)) {
     error = "Please select a " + fieldName + "\n\n\n";
    }
return error;
}

// valid selector from dropdown list

function checkDropdown(choice,fieldName) {
var error = "";
    if (choice == 0) {
    error = "Please select a "+fieldName+".\n\n\n";
    }    
return error;
}