related recipes included when adding mealplan to shopping list

cookbook/helper/shopping_helper.py

@@ -1,11 +1,15 @@
 from datetime import timedelta
+from decimal import Decimal
 
 from django.contrib.postgres.aggregates import ArrayAgg
 from django.db.models import F, OuterRef, Q, Subquery, Value
 from django.db.models.functions import Coalesce
 from django.utils import timezone
 
-from cookbook.models import UserPreference
+from cookbook.helper.HelperFunctions import Round, str2bool
+from cookbook.models import (Ingredient, ShoppingListEntry, ShoppingListRecipe,
+                             SupermarketCategoryRelation)
+from recipes import settings
 
 
 def shopping_helper(qs, request):
@@ -35,3 +39,77 @@ def shopping_helper(qs, request):
         supermarket_order = ['checked'] + supermarket_order
 
     return qs.order_by(*supermarket_order).select_related('unit', 'food', 'ingredient', 'created_by', 'list_recipe', 'list_recipe__mealplan', 'list_recipe__recipe')
+
+
+def list_from_recipe(list_recipe=None, recipe=None, mealplan=None, servings=None, ingredients=None, created_by=None, space=None, append=False):
+    """
+    Creates ShoppingListRecipe and associated ShoppingListEntrys from a recipe or a meal plan with a recipe
+    :param list_recipe: Modify an existing ShoppingListRecipe
+    :param recipe: Recipe to use as list of ingredients.  One of [recipe, mealplan] are required
+    :param mealplan: alternatively use a mealplan recipe as source of ingredients
+    :param servings: Optional: Number of servings to use to scale shoppinglist.  If servings = 0 an existing recipe list will be deleted
+    :param ingredients: Ingredients, list of ingredient IDs to include on the shopping list.  When not provided all ingredients will be used
+    :param append: If False will remove any entries not included with ingredients, when True will append ingredients to the shopping list
+    """
+    # TODO cascade to related recipes
+    r = recipe or getattr(mealplan, 'recipe', None) or getattr(list_recipe, 'recipe', None)
+    if not r:
+        raise ValueError(_("You must supply a recipe or mealplan"))
+
+    created_by = created_by or getattr(mealplan, 'created_by', None) or getattr(list_recipe, 'created_by', None)
+    if not created_by:
+        raise ValueError(_("You must supply a created_by"))
+
+    if type(servings) not in [int, float]:
+        servings = getattr(mealplan, 'servings', 1.0)
+
+    shared_users = list(created_by.get_shopping_share())
+    shared_users.append(created_by)
+    if list_recipe:
+        created = False
+    else:
+        list_recipe = ShoppingListRecipe.objects.create(recipe=r, mealplan=mealplan, servings=servings)
+        created = True
+
+    if servings == 0 and not created:
+        list_recipe.delete()
+        return []
+    elif ingredients:
+        ingredients = Ingredient.objects.filter(pk__in=ingredients, space=space)
+    else:
+        ingredients = Ingredient.objects.filter(step__recipe=r, space=space)
+
+    add_ingredients = ingredients.values_list('id', flat=True)
+    if not append:
+        existing_list = ShoppingListEntry.objects.filter(list_recipe=list_recipe)
+        # delete shopping list entries not included in ingredients
+        existing_list.exclude(ingredient__in=ingredients).delete()
+        # add shopping list entries that did not previously exist
+        add_ingredients = set(add_ingredients) - set(existing_list.values_list('ingredient__id', flat=True))
+    add_ingredients = Ingredient.objects.filter(id__in=add_ingredients, space=space)
+
+    # if servings have changed, update the ShoppingListRecipe and existing Entrys
+    if servings <= 0:
+        servings = 1
+    servings_factor = servings / r.servings
+    if not created and list_recipe.servings != servings:
+        update_ingredients = set(ingredients.values_list('id', flat=True)) - set(add_ingredients.values_list('id', flat=True))
+        for sle in ShoppingListEntry.objects.filter(list_recipe=list_recipe, ingredient__id__in=update_ingredients):
+            sle.amount = sle.ingredient.amount * Decimal(servings_factor)
+            sle.save()
+
+    # add any missing Entrys
+    for i in [x for x in add_ingredients if not x.food.ignore_shopping]:
+
+        ShoppingListEntry.objects.create(
+            list_recipe=list_recipe,
+            food=i.food,
+            unit=i.unit,
+            ingredient=i,
+            amount=i.amount * Decimal(servings_factor),
+            created_by=created_by,
+            space=space,
+        )
+
+    # return all shopping list items
+    return list_recipe