Add historical amounts to new purchase Order Form, allow extra columns etc.

tailbone/views/purchases/batch.py

@@ -26,11 +26,15 @@ Views for purchase order batches
 
 from __future__ import unicode_literals, absolute_import
 
+from sqlalchemy import orm
+
+from rattail import enum
 from rattail.db import model, api
 from rattail.gpc import GPC
 from rattail.db.batch.purchase.handler import PurchaseBatchHandler
 from rattail.time import localtime
 from rattail.core import Object
+from rattail.util import OrderedDict
 
 import formalchemy as fa
 
@@ -271,14 +275,6 @@ class PurchaseBatchView(BatchMasterView):
         batch = self.get_instance()
         if batch.executed:
             return self.redirect(self.get_action_url('view', batch))
-        vendor = batch.vendor
-        costs = Session.query(model.ProductCost)\
-                       .join(model.Product)\
-                       .outerjoin(model.Brand)\
-                       .filter(model.ProductCost.vendor == vendor)\
-                       .order_by(model.Brand.name,
-                                 model.Product.description,
-                                 model.Product.size)
 
         # organize existing batch rows by product
         order_items = {}
@@ -286,8 +282,12 @@ class PurchaseBatchView(BatchMasterView):
             if not row.removed:
                 order_items[row.product_uuid] = row
 
-        # organize product costs by dept / subdept
+        # organize vendor catalog costs by dept / subdept
         departments = {}
+        costs = self.get_order_form_costs(batch.vendor)\
+                    .order_by(model.Brand.name,
+                              model.Product.description,
+                              model.Product.size)
         for cost in costs:
 
             department = cost.product.department
@@ -318,6 +318,27 @@ class PurchaseBatchView(BatchMasterView):
             subdept_costs.append(cost)
             cost._batchrow = order_items.get(cost.product_uuid)
 
+            # do anything else needed to satisfy template display requirements etc.
+            self.decorate_order_form_cost(cost)
+
+        # fetch last 6 purchases for this vendor, organize line items by product
+        history = OrderedDict()
+        purchases = Session.query(model.Purchase)\
+                           .filter(model.Purchase.vendor == batch.vendor)\
+                           .filter(model.Purchase.status >= enum.PURCHASE_STATUS_ORDERED)\
+                           .order_by(model.Purchase.date_ordered.desc(), model.Purchase.created.desc())\
+                           .options(orm.joinedload(model.Purchase.items))[:6]
+        for purchase in purchases[:6]:
+            items = {}
+            for item in purchase.items:
+                items[item.product_uuid] = item
+            history[purchase.uuid] = {'purchase': purchase, 'items': items}
+
+        # reverse sorting and pad history as needed, for template convenience
+        for i in range(6 - len(history)):
+            history[i] = None
+        history = OrderedDict([(i, v) for i, v in enumerate(reversed(list(history.itervalues())))])
+
         title = self.get_instance_title(batch)
         return self.render_to_response('order_form', {
             'batch': batch,
@@ -325,11 +346,21 @@ class PurchaseBatchView(BatchMasterView):
             'instance_title': title,
             'index_title': "{}: {}".format(self.get_model_title(), title),
             'index_url': self.get_action_url('view', batch),
-            'vendor': vendor,
+            'vendor': batch.vendor,
             'departments': departments,
+            'history': history,
             'get_upc': lambda p: p.upc.pretty() if p.upc else '',
         })
 
+    def get_order_form_costs(self, vendor):
+        return Session.query(model.ProductCost)\
+                      .join(model.Product)\
+                      .outerjoin(model.Brand)\
+                      .filter(model.ProductCost.vendor == vendor)
+
+    def decorate_order_form_cost(self, cost):
+        pass
+
     def order_form_update(self):
         """
         Handles AJAX requests to update current batch, from Order Form view.