ALC: fix use of product minimal stock

orders/static/js/orders_helper.js

@@ -284,9 +284,13 @@ function compute_purchase_qty_for_coverage(product, coeff, stock, incoming_qty,
         purchase_package_qty_for_coverage = 1;
 
     } else {
-        purchase_qty_for_coverage = days * daily_conso - stock - incoming_qty + product.minimal_stock;
+        purchase_qty_for_coverage = days * daily_conso - stock - incoming_qty;
         purchase_qty_for_coverage = (purchase_qty_for_coverage < 0) ? 0 : purchase_qty_for_coverage;
 
+        if (purchase_qty_for_coverage + stock + incoming_qty < product.minimal_stock) {
+            purchase_qty_for_coverage = product.minimal_stock - stock - incoming_qty;
+        }
+
         // Reduce to nb of packages to purchase
         purchase_package_qty_for_coverage = purchase_qty_for_coverage / product.suppliersinfo[0].package_qty;