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doc/index_en.rst

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+Stock Supply Module
+###################
+
+The Stock Supply module add automatic supply mechanisms and introduce
+the concepts of order point and purchase request.
+
+
+Purchase Request
+****************
+
+A purchase request define the need for the purchase of a product. It
+is linked to a warehouse and eventually a supplier, it contains a
+ideal purchase date and an expected supply date. A purchase request
+can be in one of these states:
+
+Draft
+
+  A draft purchase request is a request that is not linked to a
+  purchase.
+
+Purchased
+
+  A Purchased request is a request that is linked to a purchase which
+  is not in state Done or Cancel.
+
+Done
+
+  A purchase request is in state Done if it is linked to a Purchase
+  which is in state Done.
+
+Cancel
+
+  A purchase request is in state Cancel if it is linked to a Purchase
+  which is cancelled.
+
+A wizard allow to create purchases based on a selection of Draft
+purchase requests. The new purchases contains one purchase line by
+purchase request and group them by warehouse and by supplier. Once the
+purchases are created, the corresponding purchase requests are set to
+the state Purchased.
+
+
+Order Point
+***********
+
+An order point define minimum and maximum quantities for a product on
+a location. The minimum quantity is the quantity that should be always
+(if possible) available. The maximum is a target quantity that should
+be reached when re-ordering. An order point also define a type which
+can be:
+
+Internal
+
+  An Internal order point is defined on a Storage location, it also
+  define a provisioning location. If the minimum quantity is reached
+  it will result in the creation of an internal packing between the
+  provisioning location and the Storage location.
+
+Purchase
+
+  A Purchase order point is defined on a warehouse location. If the
+  minimal quantity is reached on the warehouse it will result in a
+  purchase request.
+
+The internal packings and purchase requests are created by schedulers
+with respect to stock levels and existing packings and requests.