more testing and queue work

sql/master_schema_rollup.sql

@@ -2535,3 +2535,79 @@ DROP TRIGGER IF EXISTS on_new_recipe_collection_share ON public.shared_recipe_co
 CREATE TRIGGER on_new_recipe_collection_share
   AFTER INSERT ON public.shared_recipe_collections
   FOR EACH ROW EXECUTE FUNCTION public.log_new_recipe_collection_share();
+
+-- =================================================================
+-- Function: get_best_sale_prices_for_all_users()
+-- Description: Retrieves the best sale price for every item on every user's watchlist.
+-- This is a highly efficient function designed for the daily deal check background job.
+-- It replaces the need to call get_best_sale_prices_for_user for each user individually.
+-- Returns: TABLE(...) - A set of records including user details and deal information.
+-- =================================================================
+CREATE OR REPLACE FUNCTION public.get_best_sale_prices_for_all_users()
+RETURNS TABLE(
+    user_id uuid,
+    email text,
+    full_name text,
+    master_item_id integer,
+    item_name text,
+    best_price_in_cents integer,
+    store_name text,
+    flyer_id integer,
+    valid_to date
+) AS $$
+BEGIN
+    RETURN QUERY
+    WITH
+    -- Step 1: Find all flyer items that are currently on sale and have a valid price.
+    current_sales AS (
+        SELECT
+            fi.master_item_id,
+            fi.price_in_cents,
+            f.store_name,
+            f.flyer_id,
+            f.valid_to
+        FROM public.flyer_items fi
+        JOIN public.flyers f ON fi.flyer_id = f.flyer_id
+        WHERE
+            fi.master_item_id IS NOT NULL
+            AND fi.price_in_cents IS NOT NULL
+            AND f.valid_to >= CURRENT_DATE
+    ),
+    -- Step 2: For each master item, find its absolute best (lowest) price across all current sales.
+    -- We use a window function to rank the sales for each item by price.
+    best_prices AS (
+        SELECT
+            cs.master_item_id,
+            cs.price_in_cents AS best_price_in_cents,
+            cs.store_name,
+            cs.flyer_id,
+            cs.valid_to,
+            -- Rank items by price, ascending. The best price will have a rank of 1.
+            ROW_NUMBER() OVER(PARTITION BY cs.master_item_id ORDER BY cs.price_in_cents ASC) as price_rank
+        FROM current_sales cs
+    )
+    -- Step 3: Join the best-priced items with the user watchlist and user details.
+    SELECT
+        u.user_id,
+        u.email,
+        p.full_name,
+        bp.master_item_id,
+        mgi.name AS item_name,
+        bp.best_price_in_cents,
+        bp.store_name,
+        bp.flyer_id,
+        bp.valid_to
+    FROM public.user_watched_items uwi
+    -- Join with users and profiles to get user details for notifications.
+    JOIN public.users u ON uwi.user_id = u.user_id
+    JOIN public.profiles p ON u.user_id = p.user_id
+    -- Join with the best-priced items.
+    JOIN best_prices bp ON uwi.master_item_id = bp.master_item_id
+    -- Join with master items to get the item name.
+    JOIN public.master_grocery_items mgi ON bp.master_item_id = mgi.master_grocery_item_id
+    WHERE
+        -- Only include the items that are at their absolute best price (rank = 1).
+        bp.price_rank = 1;
+END;
+$$ LANGUAGE plpgsql;
+