Limit Quantities for Downloads and Virtual Products [Support Thread]

[lat9]

It works on the 1st time you add from the Product page but if you go to the Product page again and do the add you continue to be able to get an additional Product in the cart ...

To replicate this, you need to be adding a Download Product that has 2 downloads like the Demo Product for:
/index.php?main_page=product_info&cPath=54_60&products_id=133

Hmm, I'm not seeing that. If I add the English/PDF option it adds to cart. I return to the product page to add another English/PDF and get the "I limited your quantity" message and only 1 is in the cart. I return to the product page and add English/Word and it properly adds.

[Ajeh]

Are you using this in Zen Cart v1.5 or v1.5.1 or which version ... I trip the error by add quantity 1 from:
/index.php?main_page=product_info&cPath=54_60&products_id=133

Then go to:
/index.php?main_page=product_info&cPath=54_60&products_id=133

and add quantity 1 and I now have 2 in the shopping_cart ...

This is in v1.5.1 and in v1.5 ...

Sorry I could not get to this earlier today ...

[lat9]

Using ZC 1.5.1 (two localhost installations), PHP 5.3.8 (although I don't think that that's the difference). Using the following for /includes/extra_cart_actions/limit_downloads.php:

<?php
/**
 * Extra shopping Cart actions supported.
 *
 * @copyright Copyright 2009-2012 Vinos de Frutas Tropicales
 * @copyright Copyright 2003-2010 Zen Cart Development Team
 * @copyright Portions Copyright 2003 osCommerce
 * @license http://www.zen-cart.com/license/2_0.txt GNU Public License V2.0
 * @version $Id: limit_downloads.php 2012-11-26 lat9
 *
 * The main cart actions supported by the current shoppingCart class.
 *
 * This module checks for a downloadable and/or virtual product already present in the cart and disallows an additional product
 * quantities of the exactly-same configuration to be added.
 *
 * NOTE:  See also \includes\languages\english\extra_definitions\YOURTEMPLATE\limit_downloads.php for language constants.
 *
 */

switch ($_GET['action']) {
  /*---- Update product quantities in the cart ----
  */
  case 'update_product':
    if (isset($_POST['products_id'])) {
      for ($i = 0, $n=sizeof($_POST['products_id']); $i < $n; $i++) {   
        if (!(in_array($_POST['products_id'][$i], (is_array($_POST['cart_delete']) ? $_POST['cart_delete'] : array()))) && $_POST['cart_quantity'][$i] > 1 ) {
          if (isset($_POST['id'][$_POST['products_id'][$i]])) {
            foreach($_POST['id'][$_POST['products_id'][$i]] as $option => $value) {
              if (ldProductIsDownload ($_POST['products_id'][$i], $option, $value)) {
                $_POST['cart_quantity'][$i] = 1;
                $messageStack->add_session('header', sprintf(ERROR_MAXIMUM_DOWNLOADS, zen_get_products_name($_POST['products_id'][$i])), 'caution');
                break;
              }
            }
          } 
        }
      }
    }
  break;
  /*---- Add a product to cart ----
  **
  ** If a product is being added to the cart (with a quantity greater than 0) and that product includes attributes (the $_POST['id'] array
  ** is set), then if either that product is already in the cart -OR- if the quantity to be added is greater than 1,
  ** check each of the attributes being added to see if there is a download/virtual product amongst them.  If so,
  ** don't allow the duplicate download/virtual product to be added to the cart ... or just add 1 if this is the original add.
  */
  case 'add_product':
//-bof-v1.1.1c
    if (isset($_POST['products_id']) && $_POST['cart_quantity'] > 0 && isset($_POST['id']) && is_array($_POST['id'])) {
      $the_ids = $_POST['id'];
      foreach($_POST['id'] as $option => $value) {
        if (ldProductIsDownload ($_POST['products_id'], $option, $value)) {
          if ($_SESSION['cart']->in_cart(zen_get_uprid($_POST['products_id'], $the_ids))) {
            $messageStack->add_session('header', sprintf(ERROR_MAXIMUM_DOWNLOADS, zen_get_products_name($_POST['products_id'])), 'caution');
            zen_redirect(zen_href_link($goto, zen_get_all_get_params($parameters)));
            
          } elseif ($_POST['cart_quantity'] > 1) {
            $_POST['cart_quantity'] = 1;
            $messageStack->add_session('header', sprintf(ERROR_MAXIMUM_DOWNLOADS, zen_get_products_name($_POST['products_id'])), 'caution');
            
          }
          break;
        }
      }
    }
//-eof-v1.1.1c
  break;
}

function ldProductIsDownload ($products_id, $options_id, $options_value_id) {
  global $db, $zco_notifier;
  if (zen_get_products_virtual($products_id)) return true;
  
  $sql = "SELECT count(*) as count
          FROM " . TABLE_PRODUCTS_ATTRIBUTES_DOWNLOAD . " pad, " . TABLE_PRODUCTS_ATTRIBUTES . " pa
          WHERE pa.products_id = " . (int)$products_id . "
          AND   pa.options_id = " . (int)$options_id . "
          AND   pa.options_values_id = " . (int)$options_value_id . "
          AND   pa.products_attributes_id = pad.products_attributes_id";
  $sql_result = $db->Execute($sql);

  $zco_notifier->notify('LD_CHECK', array ('products_id' => $products_id, 'options_id' => $options_id, 'options_value_id' => $options_value_id, 'is_download' => $sql_result->fields['count']));
  return ($sql_result->fields['count'] > 0) ? true : false;
}

Using index.php?main_page=product_info&products_id=133, I add "quantity = 1" to the cart (English/PDF) and go back to add another "quantity=1" (English/PDF) and receive the message "The quantity for Multiple Downloads was adjusted in your cart. Your cart can hold at most one copy of each customization for a downloadable/virtual product.". I can add "quantity = 1" of the Spanish/PDF version.

I'm perplexed as to why your installation isn't experiencing the same behavior.

[Ajeh]

And we have a winner!

Using that code it works properly on Single Download, Multiple Download and Triple Download, tossed that in for giggles and grins, and now works in v1.3.9h, v1.5, v1.5.1, as well as the up and coming v1.5.2 and v1.6

Excellent job and thanks for the assist ...

Now I just have to fun the weird bug this tripped on a code fix that I did from my original code that tells me we doth have a potential bug in some re-writes I am working on in the shopping cart class ... but that is new code and nothing you did wrong, just helped to trigger a bizzaro error that I will need the guys to help me sort through my madness ...

Thanks again for the excellent code and hope nobody can come along and break it ...

[lat9]

Nobody else, that is! Thanks for the update that it's working, now. I'll get this packaged up to the Plugins.

[Ajeh]

I appreciate you taking the time to work through this so that even I cannot break things ... yet ... a definite asset to the community ...

[DivaVocals]

I have been sitting back watching two of the smartest women in this community working it out!!! AWESOME!!! Now that the dust has settled I can update my store..

Thanks for the hard work ladies!!!

[Ajeh]

I had the easy part ... breaking stuff ...

[DivaVocals]

I had the easy part ... breaking stuff ...

That is the fun part!!

[Ajeh]

Yes ... it is ...