Initial commit

Groceries/Home/HomeController.cs

@@ -0,0 +1,47 @@
+namespace Groceries.Home;
+
+using Groceries.Data;
+
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
+
+[Route("/")]
+public class HomeController : Controller
+{
+    private readonly AppDbContext dbContext;
+
+    public HomeController(AppDbContext dbContext)
+    {
+        this.dbContext = dbContext;
+    }
+
+    [HttpGet]
+    public async Task<IActionResult> IndexAsync()
+    {
+        var randomTagQuantity = await dbContext.ItemTagQuantities
+            .FromSql($"""
+                SELECT tag, quantity, coalesce(unit_name, unit) AS unit, is_metric, is_divisible
+                FROM (
+                    SELECT
+                        unnest(tags) AS tag,
+                        round(sum((item_quantity->'amount')::numeric * quantity), 1) AS quantity,
+                        item_quantity->>'unit' AS unit,
+                        item_quantity->'is_metric' AS is_metric,
+                        item_quantity->'is_divisible' AS is_divisible
+                    FROM item_purchases
+                    JOIN items USING (item_id)
+                    CROSS JOIN item_quantity(name)
+                    WHERE array_length(tags, 1) > 0
+                        AND age(created_at) <= '90 days'
+                        AND item_quantity IS NOT NULL
+                    GROUP BY tag, item_quantity->>'unit', item_quantity->'is_metric', item_quantity->'is_divisible'
+                    ORDER BY random()
+                    FETCH FIRST ROW ONLY
+                ) AS random_item_tag_quantity
+                LEFT JOIN item_tags USING (tag)
+                """)
+            .FirstOrDefaultAsync();
+
+        return View(randomTagQuantity);
+    }
+}