Option to hide a product when placed in cart

Well, I've already been using the tangible product with inventory management. The way that is designed, the product shows "sold out" when a quantity is zero. That's halfway to where I want to be -- I want to remove (unupublish) the object entirely so people can no longer see it when it's sold out.

Is there a hook in the Drupal API that lets me unpublish a node? Like maybe a node->unpublish or node_published = false call that I could add to the inventory management update if the quantity hits 0?

I see where this would be done in tangible.module if it's possible:

    case 'on payment completion':
      if ($node->manage_stock) {
        db_query('UPDATE {ec_product_tangible} SET stock = %d WHERE nid = %d', $node->stock - $node->qty, $node->nid);
      }
      break;

That way shoppers won't be frustrated by seeing an item they can't buy and I can set the published flag when restocking and updating inventory if I want to make the item available again.

Thank you, that's what I was looking for.

Although I'm an expert at C++, I'm still something of a newbie with PHP. Here's what I've come up with:

    case 'on payment completion':
      if ($node->manage_stock) {
        $remaining = $node->stock - $node-qty;
        db_query('UPDATE {ec_product_tangible} SET stock = %d WHERE nid = %d', $remaining, $node->nid);
        // Unpublish the node if the quantity is zero so customers don't see out of stock items.
        if( $remaining == 0 ) {
          db_query('UPDATE {node} SET status = 0 WHERE nid = %d', $node->nid);
        }
      }
      break;

Any obvious problems with the code or should that do what I want?

Nice, thank you.

And, of course, this little solution would make a great addition to the ecommerce project as a checkbox-configurable option. :)

To hide a product when it goes into someone's cart, you'd do exactly what I'm doing in the ecommerce/tangible/tangible.module, but instead of under 'on payment completion' you would use 'cart add item' like this:

case 'cart add item':
if ($node->manage_stock) {
$remaining = $node->stock - $node-qty;
db_query('UPDATE {ec_product_tangible} SET stock = %d WHERE nid = %d', $remaining, $node->nid);
// Unpublish the node if the quantity is zero so customers don't see out of stock items.
if( $remaining == 0 ) {
$node->status = 0;
node_save($node);
}
}
break;

As for automatically removing it from the cart -- I have no idea. I'm sure something could be worked in to check for that on a cron job, but haven't any idea the complexity level.