feat: Add recipe as ingredient (#4800)

Co-authored-by: Michael Genson <71845777+michael-genson@users.noreply.github.com>

mealie/services/household_services/shopping_lists.py

@@ -20,6 +20,7 @@ from mealie.schema.household.group_shopping_list import (
     ShoppingListOut,
     ShoppingListSave,
 )
+from mealie.schema.recipe.recipe import Recipe
 from mealie.schema.recipe.recipe_ingredient import (
     IngredientFood,
     IngredientUnit,
@@ -315,10 +316,22 @@ class ShoppingListService:
 
         list_items: list[ShoppingListItemCreate] = []
         for ingredient in recipe_ingredients:
+            if isinstance(ingredient.referenced_recipe, Recipe):
+                # Recursively process sub-recipe ingredients
+                sub_recipe = ingredient.referenced_recipe
+                sub_scale = (ingredient.quantity or 1) * scale
+                sub_items = self.get_shopping_list_items_from_recipe(
+                    list_id,
+                    sub_recipe.id,
+                    sub_scale,
+                    sub_recipe.recipe_ingredient,
+                )
+                list_items.extend(sub_items)
+                continue
+
             if isinstance(ingredient.food, IngredientFood):
                 food_id = ingredient.food.id
                 label_id = ingredient.food.label_id
-
             else:
                 food_id = None
                 label_id = None

mealie/services/recipe/recipe_service.py

@@ -369,6 +369,27 @@ class RecipeService(RecipeServiceBase):
 
         return new_recipe
 
+    def has_recursive_recipe_link(self, recipe: Recipe, visited: set[str] | None = None):
+        """Recursively checks if a recipe links to itself through its ingredients."""
+
+        if visited is None:
+            visited = set()
+        recipe_id = str(getattr(recipe, "id", None))
+        if recipe_id in visited:
+            return True
+
+        visited.add(recipe_id)
+        ingredients = getattr(recipe, "recipe_ingredient", [])
+        for ing in ingredients:
+            try:
+                sub_recipe = self.get_one(ing.referenced_recipe.id)
+            except (AttributeError, exceptions.NoEntryFound):
+                continue
+
+            if self.has_recursive_recipe_link(sub_recipe, visited):
+                return True
+        return False
+
     def _pre_update_check(self, slug_or_id: str | UUID, new_data: Recipe) -> Recipe:
         """
         gets the recipe from the database and performs a check to see if the user can update the recipe.
@@ -399,6 +420,9 @@ class RecipeService(RecipeServiceBase):
         if setting_lock and not self.can_lock_unlock(recipe):
             raise exceptions.PermissionDenied("You do not have permission to lock/unlock this recipe.")
 
+        if self.has_recursive_recipe_link(new_data):
+            raise exceptions.RecursiveRecipe("Recursive recipe link detected. Update aborted.")
+
         return recipe
 
     def update_one(self, slug_or_id: str | UUID, update_data: Recipe) -> Recipe: