condition check lambda

lambdas/shared/db/queries.js

@@ -0,0 +1,109 @@
+const { query } = require("./connection");
+
+/**
+ * Get rental with all related details (owner, renter, item).
+ * @param {string} rentalId - UUID of the rental
+ * @returns {Promise<object|null>} Rental with relations or null if not found
+ */
+async function getRentalWithDetails(rentalId) {
+  const result = await query(
+    `SELECT
+      r.id,
+      r."itemId",
+      r."renterId",
+      r."ownerId",
+      r."startDateTime",
+      r."endDateTime",
+      r."totalAmount",
+      r.status,
+      r."createdAt",
+      r."updatedAt",
+      -- Owner fields
+      owner.id AS "owner_id",
+      owner.email AS "owner_email",
+      owner."firstName" AS "owner_firstName",
+      owner."lastName" AS "owner_lastName",
+      -- Renter fields
+      renter.id AS "renter_id",
+      renter.email AS "renter_email",
+      renter."firstName" AS "renter_firstName",
+      renter."lastName" AS "renter_lastName",
+      -- Item fields
+      item.id AS "item_id",
+      item.name AS "item_name",
+      item.description AS "item_description"
+    FROM "Rentals" r
+    INNER JOIN "Users" owner ON r."ownerId" = owner.id
+    INNER JOIN "Users" renter ON r."renterId" = renter.id
+    INNER JOIN "Items" item ON r."itemId" = item.id
+    WHERE r.id = $1`,
+    [rentalId]
+  );
+
+  if (result.rows.length === 0) {
+    return null;
+  }
+
+  const row = result.rows[0];
+
+  // Transform flat result into nested structure
+  return {
+    id: row.id,
+    itemId: row.itemId,
+    renterId: row.renterId,
+    ownerId: row.ownerId,
+    startDateTime: row.startDateTime,
+    endDateTime: row.endDateTime,
+    totalAmount: row.totalAmount,
+    status: row.status,
+    createdAt: row.createdAt,
+    updatedAt: row.updatedAt,
+    owner: {
+      id: row.owner_id,
+      email: row.owner_email,
+      firstName: row.owner_firstName,
+      lastName: row.owner_lastName,
+    },
+    renter: {
+      id: row.renter_id,
+      email: row.renter_email,
+      firstName: row.renter_firstName,
+      lastName: row.renter_lastName,
+    },
+    item: {
+      id: row.item_id,
+      name: row.item_name,
+      description: row.item_description,
+    },
+  };
+}
+
+/**
+ * Get user by ID.
+ * @param {string} userId - UUID of the user
+ * @returns {Promise<object|null>} User or null if not found
+ */
+async function getUserById(userId) {
+  const result = await query(
+    `SELECT
+      id,
+      email,
+      "firstName",
+      "lastName",
+      phone
+    FROM "Users"
+    WHERE id = $1`,
+    [userId]
+  );
+
+  if (result.rows.length === 0) {
+    return null;
+  }
+
+  return result.rows[0];
+}
+
+module.exports = {
+  getRentalWithDetails,
+  getUserById,
+};