From a686500df15a5315389d5b63a85a2a611884eb57 Mon Sep 17 00:00:00 2001
From: Oliver Walters <oliver.henry.walters@gmail.com>
Date: Sun, 4 Oct 2020 21:02:20 +1100
Subject: [PATCH] Calculate initial values for the view

---
 InvenTree/stock/models.py |  3 ++-
 InvenTree/stock/views.py  | 57 ++++++++++++++++++++++++++++-----------
 2 files changed, 44 insertions(+), 16 deletions(-)

diff --git a/InvenTree/stock/models.py b/InvenTree/stock/models.py
index df1a628f47..62b774dd06 100644
--- a/InvenTree/stock/models.py
+++ b/InvenTree/stock/models.py
@@ -600,12 +600,13 @@ class StockItem(MPTTModel):
         return self.installedItemCount() > 0
 
     @transaction.atomic
-    def installIntoStockItem(self, otherItem, user, notes):
+    def installIntoStockItem(self, otherItem, quantity, user, notes):
         """
         Install this stock item into another stock item.
 
         Args
             otherItem: The stock item to install this item into
+            quantity: The quantity of stock to install
             user: The user performing the operation
             notes: Any notes associated with the operation
         """
diff --git a/InvenTree/stock/views.py b/InvenTree/stock/views.py
index 1f6ddcc0f4..541c60b2f5 100644
--- a/InvenTree/stock/views.py
+++ b/InvenTree/stock/views.py
@@ -699,25 +699,52 @@ class StockItemInstall(AjaxUpdateView):
     form_class = StockForms.InstallStockForm
     ajax_form_title = _('Install Stock Item')
 
+    def get_stock_items(self):
+        """
+        Return a list of stock items suitable for displaying to the user.
+
+        Requirements:
+        - Items must be in stock
+        
+        Filters:
+        - Items can be filtered by Part reference
+        """
+
+        items = StockItem.objects.filter(StockItem.IN_STOCK_FILTER)
+
+        # Filter by Part association
+        try:
+            part = self.request.GET.get('part', None)
+
+            print(self.request.GET)
+
+            if part is not None:
+                part = Part.objects.get(pk=part)
+                items = items.filter(part=part)
+        except (ValueError, Part.DoesNotExist):
+            pass
+
+        return items
+
+    def get_initial(self):
+
+        initials = super().get_initial()
+
+        items = self.get_stock_items()
+
+        # If there is a single stock item available, we can use it!
+        if items.count() == 1:
+            item = items.first()
+            initials['stock_item'] = item.pk
+            initials['quantity_to_install'] = item.quantity
+        
+        return initials
+
     def get_form(self):
 
         form = super().get_form()
 
-        queryset = form.fields['stock_item'].queryset
-
-        part = self.request.GET.get('part', None)
-
-        # Filter the available stock items based on the Part reference
-        if part:
-            try:
-                part = Part.objects.get(pk=part)
-
-                queryset = queryset.filter(part=part)
-
-            except (ValueError, Part.DoesNotExist):
-                pass
-
-        form.fields['stock_item'].queryset = queryset
+        form.fields['stock_item'].queryset = self.get_stock_items()
 
         return form