function activate_cc(s_icons_url) {
   s_checkout_img = s_icons_url + "checkout.gif" ;
   s_google_checkout_img = "https://checkout.google.com/buttons/checkout.gif?merchant_id=475906207481918&w=160&h=43&style=white&variant=text&loc=en_US" ;
   obj_checkout_img = document.getElementById("checkout_button") ;      
	
   obj_payment = document.getElementById("payment_method_id") ; 
   payment_name = obj_payment.options[obj_payment.selectedIndex].text ;   
    
   obj_cc_number = document.getElementById("cc_number") ;
   obj_cc_month = document.getElementById("cc_month") ;
   obj_cc_year = document.getElementById("cc_year") ;
   obj_cc_cvv = document.getElementById("cc_cvv") ;
   
   if (payment_name == "Google Checkout") {      
      obj_cc_number.readOnly = false ;
      obj_cc_month.disabled = false ;
      obj_cc_year.disabled = false ;
      obj_cc_cvv.readOnly = false ;
      
      obj_checkout_img.src = s_google_checkout_img ;
   } else {
      obj_cc_number.readOnly = true ;
      obj_cc_month.disabled = true ;
      obj_cc_year.disabled = true ;
      obj_cc_cvv.readOnly = true ;
      
      obj_checkout_img.src = s_checkout_img ;
   } 
} // function activate_cc()

// Google checkout function
function activate_gc(s_icons_url) {
   s_checkout_img = s_icons_url + "checkout.gif" ;
   s_google_checkout_img = "https://checkout.google.com/buttons/checkout.gif?merchant_id=475906207481918&w=160&h=43&style=white&variant=text&loc=en_US" ;
   obj_checkout_img = document.getElementById("checkout_button") ;      
	
   obj_payment = document.getElementById("payment_method_id") ; 
   payment_name = obj_payment.options[obj_payment.selectedIndex].text ;
   
   obj_gc_email = document.getElementById("gc_email") ;
   obj_gc_password = document.getElementById("gc_password") ;
   
   if (payment_name == "Google Checkout") {      
      obj_gc_email.readOnly = false ;
      obj_gc_password.readOnly = false ;
      
      obj_checkout_img.src = s_google_checkout_img ;
   } else {
      obj_gc_email.readOnly = true ;
      obj_gc_password.readOnly = true ;
      
      obj_checkout_img.src = s_checkout_img ;
   } 
} // activate_gc() 

// Sets all the billing variable to the shipping variable
function set_bill_2_ship() {
   obj_checkbox = document.getElementById("bill_2_ship") ;
   if (obj_checkbox.checked == false) {
   	  return ;
   }
      
   obj_bill_address = document.getElementById("bill_address") ;
   obj_bill_city = document.getElementById("bill_city") ;
   obj_bill_zip = document.getElementById("bill_zip") ;
   
   obj_ship_address = document.getElementById("ship_address") ;
   obj_ship_city = document.getElementById("ship_city") ;
   obj_ship_zip = document.getElementById("ship_zip") ;
      
   obj_ship_address.value = obj_bill_address.value ;
   obj_ship_city.value = obj_bill_city.value ;
   obj_ship_zip.value = obj_bill_zip.value ;	
} // function bill_2_ship()

function view_large_picture(id, isbn, img_height) {
   height = img_height + 80 ;
   s_wondow_attributes = 'toolbar=0,menubar=0,scrollbars=0,resizable=1,directories=0,height=' + height + ',width=720'	;
   s_large_pic_url = "http://www.combooks.co.il/Combooks_Il2/product_large_image.php?id=" + id + "&isbn=" + isbn; 
    
   window.open(s_large_pic_url, "", s_wondow_attributes) ;
} // function view_large_picture()

function change_shipping(d_sub_total, d_shipping_price, vat_percentage, currency_symbol, s_shipping_text) {
   var d_sub_total = d_sub_total ;  
   var d_vat_percentage = vat_percentage ;
   var d_total = d_sub_total ;
   
   document.getElementById("td_shipping_title").innerHTML = '<span class="ship_method_title">Shipping & Handling:</span> ' + s_shipping_text ;
   
   d_total += d_shipping_price ;
   document.getElementById("td_shipping").innerHTML = currency_symbol + d_shipping_price ;	

   // calculating vat   
   d_vat = (d_total * d_vat_percentage) / 100 ;
   d_vat = Math.round(d_vat *100) / 100 ;
   d_total += d_vat ;
     
   document.getElementById("td_vat").innerHTML = currency_symbol + d_vat.toFixed(2) ;
   document.getElementById("td_total").innerHTML = currency_symbol + d_total.toFixed(2) ;  
} // function change_shipping()

function check_all_rem(num_products) {
   s_check_all = document.getElementById("check_all_val").value ;
	
   num_of_products = parseInt(num_products) ;
   for (i_prod = 0; i_prod < num_of_products; i_prod++)	{
      s_remove_name = "remove_" + i_prod ;
      if (s_check_all == '1') {
         document.getElementById(s_remove_name).checked = true ;	
      } else {
      	 document.getElementById(s_remove_name).checked = false ;
      }	        	
   } // for (i_prod = 0;
   
   if (s_check_all == '1') {   
      document.getElementById("check_all_val").value = "0" ; 
      document.getElementById("check_all_button").value = "UnCheck All" ;     
   } else {
   	  document.getElementById("check_all_val").value = "1" ;
   	  document.getElementById("check_all_button").value = "Check All" ;
   }
} // function check_all()