function CartForm()
{
    this.step = 1;
    this.payType = "2";
    
    this.overview = document.getElementById('overview');
    //this.cardOverview = document.getElementById('cardOverview');
    this.checkoutCart = document.getElementById('checkoutCart');
    this.SubmitOrder = document.getElementById('SubmitOrder');
    this.errorMessage = document.getElementByClassName('p','errormessage');
    this.personalDetails = document.getElementById('personalDetails');
    this.information = document.getElementById('information');
    this.formCreditCard = document.getElementById('formCreditCard');
    this.formSchoolInvoice = document.getElementById('formSchoolInvoice');
    this.checkoutConfirmation = document.getElementById('checkoutConfirmation');
    
    if(typeof CartForm._initialized == "undefined")
    {
        CartForm.prototype.hideAll = function()
        {
            this.overview.style.display = "none";
            //this.cardOverview.style.display = "none";
            this.checkoutCart.style.display = "none";
            //this.buyersInfo.style.display = "none";
            this.errorMessage.style.display = "none";
            this.personalDetails.style.display = "none";
            this.information.style.display = "none";
            this.formCreditCard.style.display = "none";
            this.formSchoolInvoice.style.display = "none"; 
            this.checkoutConfirmation.style.display = "none";
            
            if((this.step == 2)&&(this.payType == "3"))
            {
                var oExtras = document.getInnerElementByClassName(this.formSchoolInvoice,'div','formExtras');
                oExtras.style.display = "block";
                oExtras = document.getInnerElementByClassName(this.formCreditCard, 'div','formExtras');
                oExtras.style.display = "none";
            }         
        };
        
        CartForm.prototype.goTo2 = function()
        {
          if(!oCart.loaded)return false;
              
              if(this.payType == "2" && oCart.hasInspectedItem())
              {                 
                 alert("Inspection copies may only be requested by schools.");
                 return false;
              }
                    
              var validate = this.validateStep1();
              if(!validate) return false;
              
              this.hideAll();
              this.step++;
              this.overview.innerHTML = "";
              if(this.payType == "2")
              {                   
                    var oText = '<h2>Personal Credit Card details</h2><p class="beforeCart">';                
                    oText += 'Please enter your payment details.<br />';                
                    if((typeof checkTC != "undefined")&&(checkTC == true))
                    {
                      //oText += '<span>Your total purchase is $' + (Number(oCart.getEClubTotal())- oCart.handlingCharge).toFixed(2) + '</span><br /><br />';
                      //oText += 'A handling charge of <span>$' + oCart.handlingCharge + '</span> applies to personal orders.<br />';                           
                      oText += '<span>Your total charge will be $' + oCart.getEClubTotal() + '</span>';
                    } else {
                      oText += '<span>Your total purchase is $' + (Number(oCart.getTotal())- oCart.handlingCharge).toFixed(2) + '</span><br /><br />';
                      oText += 'A handling charge of <span>$' + oCart.handlingCharge + '</span> applies to personal orders.<br />';
                      oText += '<span>Your total charge will be $' + (Number(oCart.getTotal())).toFixed(2) + '</span>';
                    }
                    oText += '</p>';              
                    this.overview.innerHTML = oText;               
                    this.overview.style.display = "block";
                    this.formCreditCard.style.display = "block";
                
              } else {
                    if(this.payType == "4")
                    {
                      var oText = '<h2>School/University invoice details</h2><p class="beforeCart">';
                    } else {
                      var oText = '<h2>School/University credit card details</h2><p class="beforeCart">';
                    }
                    oText += 'Please enter your payment details.<br />';
                    if((typeof checkTC != "undefined")&&(checkTC == true))
                    {
                      oText += '<span>Your total purchase is $' + oCart.getEClubTotal() + '</span><br /><br />';
                    } else {
                      oText += '<span>Your total purchase is $' + oCart.getTotal() + '</span><br /><br />';
                    }
                    oText += '</p>';
                    this.overview.innerHTML = oText;
                    this.overview.style.display = "block";                                     
                    
                    this.formSchoolInvoice.style.display = "block";
                    
                    if(this.payType == "3")
                    {
                      var oExtras = document.getInnerElementByClassName(this.formSchoolInvoice,'div','formExtras');
                      oExtras.style.display = "none";
                      oExtras = document.getInnerElementByClassName(this.formCreditCard, 'div','formExtras');
                      oExtras.style.display = "block";
                      this.formCreditCard.style.display = "block";
                    }
              }
              oCart.updateShoppingSummary();
        };
        
        CartForm.prototype.next = function()
        {
            var payTypeList = document.forms['SubmitOrder'].CustomField_4;
            
            for(var i=0; i < payTypeList.length; i++)
            {
              if(payTypeList[i].checked)this.payType = payTypeList[i].value;
            }
           
            if(this.step == 1)
            {
              this.goTo2();
            } else if(this.step == 2)
            {
              var bValidate = false;
              if(this.payType == "2")
              {
                bValidate = this.validateCreditCard();
              } else if(this.payType == "4")
              {
                bValidate = this.validateInvoice();
              } else {
                bValidate = (this.validateCreditCard() && this.validateInvoice());
              }
              if(bValidate)
              {
                this.hideAll();
                this.step++;
                var oText = "<h2>Checkout Purchase confirmation</h2>";
                if(typeof oCart != "undefined")
                {
                  oText += oCart.getCheckoutConfirmationTable();
                  oText += this.getDeliverySummary();
                  oText += this.getPaymentSummary();
                  oText += '<p><input type="button" onclick="previous(event)" class="previousStep" value="Previous step" /></p>';
                  //oText += '<p><a href="#" onclick="previous(event)" class="previousStep">previous step</a></p>';
                  //oText += '<p><a href="#" onclick="moveNext(event)" class="nextStep">next step</a></p>';                                    
                  //oText += '<p><input type="image" src="templates/global/$file/MP_button_PurchaseNow.gif"  border="0" onclick="getCartFormFields()"></p>';
                  oText += '<p><input type="submit" onclick="getCartFormFields()" class="previousStep" value="Purchase now" /></p>';                                    
                  this.checkoutConfirmation.innerHTML = oText;
                  this.checkoutConfirmation.style.display = "block";
                }
              } 
            } else {
              this.submit();
            }
        };
        
         CartForm.prototype.previous = function()
        {
             
            this.hideAll();
            this.step--;
            
            if(this.step == "1")
            {
              this.overview.innerHTML = "";
              var oText = '<h2>Overview</h2><p class="beforeCart">';
              oText += 'If you are a Teacher e-Club member and not logged in, <a href="libraries/Teachers+Club" title="Teachers Club">login</a> now to receive your discount.<br />';
              oText += 'Non members, <a href="ibraries/Teachers+Club" title="Teachers Club">register</a> now.<br />';
              oText += 'Inspection copies can be made by schools only.';
              oText += '</p>';
              this.overview.innerHTML = oText;
              oCart.updateShoppingSummary();
              this.overview.style.display = "block";
              this.checkoutCart.style.display = "block";
              this.personalDetails.style.display = "block";
              this.information.style.display = "block";
            } else {
              if(this.payType == "2")
              {
                    var oText = '<h2>Personal Credit Card details</h2><p class="beforeCart">';                
                    oText += 'Please enter your payment details.<br />';                
                    if((typeof checkTC != "undefined")&&(checkTC == true))
                    {
                      oText += '<span>Your total purchase is $' + (Number(oCart.getEClubTotal())- oCart.handlingCharge).toFixed(2) + '</span><br /><br />';
                      oText += 'A handling charge of <span>$' + oCart.handlingCharge + '</span> applies to personal orders.<br />';                           
                      oText += '<span>Your total charge will be $' + (Number(oCart.getEClubTotal())).toFixed(2) + '</span>';
                    } else {
                      oText += '<span>Your total purchase is $' + (Number(oCart.getTotal())- oCart.handlingCharge).toFixed(2) + '</span><br /><br />';
                      oText += 'A handling charge of <span>$' + oCart.handlingCharge + '</span> applies to personal orders.<br />';
                      oText += '<span>Your total charge will be $' + (Number(oCart.getTotal())).toFixed(2) + '</span>';
                    }
                    oText += '</p>';              
                    this.overview.innerHTML = oText;               
                    this.overview.style.display = "block";
                    this.formCreditCard.style.display = "block";
                
              } else {
                    if(this.payType == "4")
                    {
                      var oText = '<h2>School/University invoice details</h2><p class="beforeCart">';
                    } else {
                      var oText = '<h2>School/University credit card details</h2><p class="beforeCart">';
                    }
                    oText += 'Please enter your payment details.<br />';
                    if((typeof checkTC != "undefined")&&(checkTC == true))
                    {
                      oText += '<span>Your total purchase is $' + oCart.getEClubTotal() + '</span><br /><br />';
                    } else {
                      oText += '<span>Your total purchase is $' + oCart.getTotal() + '</span><br /><br />';
                    }
                    oText += '</p>';
                    this.overview.innerHTML = oText;
                    this.overview.style.display = "block";                                     
                    
                    this.formSchoolInvoice.style.display = "block";
                    
                    if(this.payType == "3")
                    {
                      var oExtras = document.getInnerElementByClassName(this.formSchoolInvoice,'div','formExtras');
                      oExtras.style.display = "none";
                      oExtras = document.getInnerElementByClassName(this.formCreditCard, 'div','formExtras');
                      oExtras.style.display = "block";
                      this.formCreditCard.style.display = "block";
                    }
              }
              oCart.updateShoppingSummary();
            }                        
        };
        
        CartForm.prototype.validateStep1 = function()
        {
            var fFirstname = document.forms['SubmitOrder'].Firstname.value;
            var fLastname = document.forms['SubmitOrder'].Lastname.value;
            var fOrganisation = document.forms['SubmitOrder'].Organisation.value;
            var fPostalAddress = document.forms['SubmitOrder'].PostalAddress.value;
            var fPostalCity = document.forms['SubmitOrder'].PostalCity.value;
            var fPostalState = document.forms['SubmitOrder'].PostalState.value;
            var fPostalCode = document.forms['SubmitOrder'].PostalCode.value;
            var fPhoneNumber = document.forms['SubmitOrder'].PhoneNumber.value;
            var fEmailAddress = document.forms['SubmitOrder'].EmailAddress.value;
            
            var oText = "Please fill in the following field(s):\n";
            if(fFirstname == "" || fFirstname == " ")oText += "-Firstname\n";
            if(fLastname == "" || fLastname == " ")oText += "-Lastname\n";
            if(this.payType == "4" || this.payType == "3")
            {
                if(fOrganisation == "" || fOrganisation == " ")oText += "-School name\n";
            }   
            if(fPostalAddress == "" || fPostalAddress == " ")oText += "-Street address\n";
            if(fPostalCity == "" || fPostalCity == " ")oText += "-Suburb\n";
            if(fPostalState == "" || fPostalState == " ")oText += "-State\n";
            if(fPostalCode == "" || fPostalCode == " ")oText += "-Postal code\n";
            if(fPhoneNumber == "" || fPhoneNumber == " ")oText += "-Phone number\n";
            if(fEmailAddress == "" || fEmailAddress == " ")oText += "-Email address\n";
            
            if(oText != "Please fill in the following field(s):\n")
            {
              alert(oText);
              return false;
            }
            
            //var reEmail = /^(?:\w+\.?)*\w+@(?:\w+\.?)*\w+$/;
            var reEmail = /\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*/;
            if(!reEmail.test(fEmailAddress))
            {
              alert("Please enter a valid email address.");
              return false;
            }        
                      
            return true;
        };
                
        CartForm.prototype.validateCreditCard = function()
        {
          var fCardName = document.forms['SubmitOrder'].CardName.value;
          var fCardNumber = document.forms['SubmitOrder'].CardNumber.value;
          var fCardMonth = document.forms['SubmitOrder'].CardMonth.value;
          var fCardYear = document.forms['SubmitOrder'].CardYear.value;
          
          var oText = "Please fill in the following field(s):\n";
          if(fCardName == "" || fCardName == " ") oText += "-Card holder name\n";
          if(fCardNumber == "" || fCardNumber == " ") oText += "-Card number\n";
          if(fCardMonth == "MM" || fCardMonth == "" || fCardYear == "YY" || fCardYear == "") oText += "-Card expiry date\n";
          
          if(oText != "Please fill in the following field(s):\n")
          {
             alert(oText);
             return false;
          }
          
          var reCardNumber = /\d{16}/;
          if(!reCardNumber.test(fCardNumber))
          {
            alert("Please enter a valid credit card number.");
            return false;
          }
          
          var reYear = /\d{2}/;
          var reMonth = /0[1-9]|1[0-2]/;
          if((!reMonth.test(fCardMonth))||(!reYear.test(fCardYear)))
          {
            alert("Please enter a valid expiry date.");
            return false;
          }
          
          return true;
                    
        };
        
        CartForm.prototype.validateInvoice = function()
        {
          var fOrderNumber = document.forms['SubmitOrder'].Inv_Order_Number.value;
          var fAccountCode = document.forms['SubmitOrder'].Inv_Order_AccountCode.value;
          
          var oText = "Please fill in the following field(s):\n";
          if(fOrderNumber == "" || fOrderNumber == " ") oText += "-Customer order number\n";
          //if(fAccountCode == "" || fAccountCode == " ") oText += "-Macmillan account code\n";
          
          if(oText != "Please fill in the following field(s):\n")
          {
             alert(oText);
             return false;
          }
          
          return true;
        };
        
        CartForm.prototype.getDeliverySummary = function()
        {
          var oText = '<p class="deliverySummary"><span>Your delivery details:</span><br /><br />';
          oText += document.forms['SubmitOrder'].Firstname.value + " " + document.forms['SubmitOrder'].Lastname.value + "<br />";
          if(document.forms['SubmitOrder'].Organisation.value != "")
          {
            oText += document.forms['SubmitOrder'].Organisation.value + "<br />";
          }
          oText += document.forms['SubmitOrder'].PostalCity.value + " " + document.forms['SubmitOrder'].PostalState.value + " " + document.forms['SubmitOrder'].PostalCode.value;
          oText += "</p>";
          return oText;
        };
        
        CartForm.prototype.getPaymentSummary = function()
        {
          var oText = '<p class="paymentSummary"><span>Your payment information:</span><br /><br />';
          if(this.payType == "2" || this.payType =="3")
          {
            var nCard = "xxxx xxxx xxxx " + document.forms['SubmitOrder'].CardNumber.value.substring(12);
            oText += "Your ";
            if(this.payType == "3")oText += " school ";
            oText += document.forms['SubmitOrder'].CardType.value + " credit card ending in ";
            oText += nCard + " will be charged.<br /><br />";
          }
          if(this.payType == "3" || this.payType =="4")
          {
            oText += "Customer Order Number: " + document.forms['SubmitOrder'].Inv_Order_Number.value + ".<br /><br />";
            oText += "Account Code: " + document.forms['SubmitOrder'].Inv_Order_AccountCode.value + ".<br /><br />";
            oText += "On verification by our Customer Service department the transaction will be processed.<br /><br />";
          }
          return oText;
        };      
         
    }
    CartForm._initialized = true;
    
}