function addEvent(obj, evType, fn){ 
 if (obj.addEventListener){ 
   obj.addEventListener(evType, fn, false); 
   return true; 
 } else if (obj.attachEvent){ 
   var r = obj.attachEvent("on"+evType, fn); 
   return r; 
 } else { 
   return false; 
 } 
}


function togglePackage(form,package_type) {
    var num_packages = form.alternate_package.length;
    
    for (i=0; i<num_packages; i++) {
        if (form.alternate_package[i].checked == true) {
            //form.alternate_package[i].disabled = (form.alternate_package[i].disabled == false) ? true : false;
        }
        else {
            form.alternate_package[i].disabled = (form.alternate_package[i].disabled == false) ? true : false;
        }
    }

    document.getElementById(package_type).disabled = false;

}

function checkMMSelection(mm_selection) {
    if (document.getElementById(mm_selection).checked == true) {
        document.getElementById(mm_selection).checked = false
    }
}


function checkArchiveSelection(form) {
    
    //var browser = detectBrowser();
    var years = document.getElementsByName("archive_year");
    
    var years_selected = 0;
    
   
    for (var i=0; i<years.length; i++) {
        if (years[i].checked == true) {
            ++years_selected;
        }
    }
   
    if (document.getElementById('base_product').value == 'Archive' && years_selected == 0) {
        alert('As an Archive User you must select at least 1 archive year');
        return false;
    }
    else if (years_selected > 9) {
        alert('A maximum of 9 archive years is permitted');
        return false;
    }    
    else {
        return;
    }
}

function detectBrowser(form) {
    var browserName=navigator.appName; 
    if (browserName=="Microsoft Internet Explorer") { 
        return "IE";
    }
    else {
        return "other";
    }
}

function setOtherPackage(packageSelected) {
    document.getElementById('other_package').value = packageSelected ;
}

function expandcontent(elementid) {
    document.getElementById(elementid).style.display = (document.getElementById(elementid).style.display == 'none') ? 'block' : 'none';
}


function toggleEnable(field) {
    
    document.getElementById(field).disabled = (document.getElementById(field).disabled == false) ? true : false;    
}


function Postform (action){
   document.choose_subscription.subscription.value=action;
   document.choose_subscription.submit();
}

function showProduct(product,selection,class_arg,price) {
    var submitForm=1;
    
    if (product=='submit') {
        document.getElementById("base_product").value=selection;
        document.choose_subscription.submit();
    }

    for (var i=1; i<6; i++) {
       document.getElementById('tab' + i).className = "";
    }
    document.getElementById('tab'+ product).className = "selected";

    for (var i=1; i<6; i++) {
       document.getElementById('product'+i).style.display = 'none';
    }
    document.getElementById('product' + product).style.display = 'block';
    
    
    //alert(document.getElementById('product3').style.display + product);
    
    switch (product){
        case "1":
            document.getElementById("type_of_product").innerHTML='Regional Products';
            break;
        case "2":
            document.getElementById("type_of_product").innerHTML='National Products';
            break;
        case "3":
            document.getElementById("type_of_product").innerHTML='Packages';            
            break;
       case "4":
            document.getElementById("type_of_product").innerHTML='Value Added Products';
            break;  
       case "5":
            document.getElementById("type_of_product").innerHTML='Upgrade Products';
            submitForm=0;
            break;  
    }
    document.getElementById("base_product").value=selection;
    //document.getElementById("selectedProd").className=class_arg;
    //document.getElementById("prodPrice").innerHTML=price;
        
    if (submitForm==1) {
        return true;
    }
    else {
        return false;
    }
}


function currencyConvertor(form) {
    var conversion=1.49;
           
    var ua = window.navigator.userAgent;
    var msie = ua.indexOf ( "MSIE" );

    if ( msie > 0 ) {      // If Internet Explorer, return version number
        currencyConvertorIE(form,conversion);
    }
    else {                 // If another browser, return 0
        currencyConvertorOther(form,conversion);
    }
}
 
function currencyConvertorIE(form,conversion) {
    // retrieve all span tags
    var spans = document.getElementsByTagName("span");    
      
    for (var i=0; i < spans.length; i++) {
        // if currency selected is true
        // then we want euro prices and display
        if (form.currency_select.checked == true && !form.euro) {
            if (!form.euro && spans[i].name == "currency") {
                spans[i].innerHTML = "&euro;";
            }
            else if (spans[i].name == "price") {
                var cost = spans[i].innerHTML *= conversion;
                spans[i].innerHTML = cost.toFixed(2);
                
                
            }
        }
        else if( form.euro ) {
            if (spans[i].name == "currency") {
                spans[i].innerHTML = "&pound;";
            }
            else if (spans[i].name == "price") {
                var cost = spans[i].innerHTML /= conversion;
                spans[i].innerHTML = cost.toFixed(2);
            } 
        }
    } 
    form.euro = form.currency_select.checked;
}

function currencyConvertorOther(form,conversion) {

var currency = document.getElementsByName("currency");
var price = document.getElementsByName("price");
  
 //  alert(price.length);
      
   for (var i=0; i < price.length; i++) {
    var num = price[i].innerHTML;
    if (form.currency_select.checked == true && currency[i].innerHTML == "£") {
        
        num *= conversion;
        var result = num.toFixed(2); 
        price[i].innerHTML = result;
        currency[i].innerHTML = "&euro;";
    }
   else if (currency[i].innerHTML != "£") {
            
        num /= conversion;
        var result=num.toFixed(2); 
        price[i].innerHTML = result;
        currency[i].innerHTML = "&pound;";
    }
  }
}