munch-ease-backend/shopping/__init__.py

from typing import Any, AsyncIterator, Dict, Iterator, List, Tuple
from shopping.db import ShoppingList, ShoppingListItem, load_shopping_list, purchase, remove_request, request

from shopping.db import find_items_by_list_id as _find_items_by_list_id, get_purchased_ingredients as _get_purchased_ingredients

import meals, recipes, ingredients

async def to_lookups(conn, items: List[ShoppingListItem], meals_lookup: Dict[int, Any] = None, recipes_lookup: Dict[int, Any] = None, ingredients_lookup: Dict[int, Any] = None) -> Tuple[Dict[int, Any], Dict[int, Any], Dict[int, Any]]:
    meals_lookup = meals_lookup or {}
    recipes_lookup = recipes_lookup or {}
    ingredients_lookup = ingredients_lookup or {}

    await _ensure_lookups_populated(conn, items, meals_lookup, recipes_lookup, ingredients_lookup)
    return meals_lookup, recipes_lookup, ingredients_lookup


async def _ensure_lookups_populated(conn, items: List[ShoppingListItem], meals_lookup, recipes_lookup, ingredients_lookup):
    for item in items:
        # If the any item is not in the lookup, we need to add it
        if item.meal_id and item.meal_id not in meals_lookup:
            meals_lookup[item.meal_id] = await meals.find_meal_by_id(conn, item.meal_id)
        if item.recipe_id and item.recipe_id not in recipes_lookup:
            recipes_lookup[item.recipe_id] = await recipes.find_recipe_by_id(conn, item.recipe_id)
        if item.ingredient_id and item.ingredient_id not in ingredients_lookup:
            ingredients_lookup[item.ingredient_id] = await ingredients.find_ingredient_by_id(conn, item.ingredient_id)

async def get_persons_requests(conn, person_id: int) -> List[ingredients.Ingredient]:
    ids = [item.ingredient_id async for item in _find_items_by_list_id(conn, None) if item.person_id == person_id and item.ingredient_id is not None and item.meal_id is None]
    return [await ingredients.find_ingredient_by_id(conn, ingredient_id) for ingredient_id in ids]

def flatten_items(items: Iterator[ShoppingListItem], meals_lookup: Dict[int, Any]) -> Iterator[ShoppingListItem]:
    for item in items:
        if item.meal_id and item.meal_id in meals_lookup:
            meal = meals_lookup[item.meal_id]
            for mealRecipe in meal.recipes:
                for ingredient in mealRecipe.recipe.ingredients:
                    yield ShoppingListItem(
                        ingredient_id=ingredient.id, 
                        meal_id=item.meal_id, 
                        recipe_id=mealRecipe.recipe.id, 
                        person_id=item.person_id, 
                        created_date=item.created_date
                    )

            for ingredient in meal.extra_ingredients:
                yield ShoppingListItem(
                    ingredient_id=ingredient.id, 
                    meal_id=item.meal_id, 
                    person_id=item.person_id, 
                    created_date=item.created_date
                )
        else:
            yield item

async def get_outstanding_requests(conn) -> Tuple[List[ShoppingListItem], List[ShoppingListItem], List[ShoppingListItem], Dict[int, Any], Dict[int, Any], Dict[int, Any]]:
    current_requests = [r async for r in _find_items_by_list_id(conn, None)]
    meal_requests = [r for r in current_requests if r.meal_id is not None and r.meal_id > 0]
    
    # Get lookups for meals to enable flattening
    meals_lookup, recipes_lookup, ingredients_lookup = await to_lookups(conn, current_requests)
    
    meal_ids = [r.meal_id for r in meal_requests if r.meal_id]
    purchased_ingredients = {(r.ingredient_id, r.meal_id, r.recipe_id): r async for r in _get_purchased_ingredients(conn, meal_ids)}

    outstanding_items = []
    purchased_items = []
    flattened = list(flatten_items(current_requests, meals_lookup))
    
    # Now ensure that all ingredients from the flattened items are in the lookup
    await _ensure_lookups_populated(conn, flattened, meals_lookup, recipes_lookup, ingredients_lookup)
    
    for r in flattened:
        # Meal ingredients may have already been purchased
        if r.meal_id is not None and r.meal_id > 0:
            purchased_item = purchased_ingredients.get((r.ingredient_id, r.meal_id, r.recipe_id))
            if purchased_item:
                purchased_items.append(purchased_item)
                continue

        outstanding_items.append(r)

    return outstanding_items, purchased_items, meal_requests, meals_lookup, recipes_lookup, ingredients_lookup