feat(plan): resolveGrid for batch cell resolution

src/__tests__/plan.test.ts

@@ -1,6 +1,6 @@
 import { describe, it, expect, beforeAll, afterAll, beforeEach } from "vitest";
 import prisma from "../config/database";
-import { resolveCell } from "../services/plan.service";
+import { resolveCell, resolveGrid } from "../services/plan.service";
 
 // ---------------------------------------------------------------------------
 // Test fixtures
@@ -119,3 +119,54 @@ describe("plan.service.resolveCell", () => {
     expect(result).toBeNull();
   });
 });
+
+// ---------------------------------------------------------------------------
+// resolveGrid
+// ---------------------------------------------------------------------------
+
+describe("plan.service.resolveGrid", () => {
+  it("returns a 2D map keyed by userId then date", async () => {
+    await prisma.work_plan_entries.create({
+      data: {
+        user_id: adminUserId,
+        date_from: new Date("2099-06-01"),
+        date_to: new Date("2099-06-03"),
+        category: "work",
+        note: `${N}A`,
+        created_by: adminUserId,
+      },
+    });
+    const cells = await resolveGrid([adminUserId], "2099-06-01", "2099-06-05");
+    expect(cells[adminUserId]["2099-06-01"]?.note).toBe(`${N}A`);
+    expect(cells[adminUserId]["2099-06-02"]?.note).toBe(`${N}A`);
+    expect(cells[adminUserId]["2099-06-03"]?.note).toBe(`${N}A`);
+    expect(cells[adminUserId]["2099-06-04"]).toBeNull();
+    expect(cells[adminUserId]["2099-06-05"]).toBeNull();
+  });
+
+  it("applies override on a covered day", async () => {
+    await prisma.work_plan_entries.create({
+      data: {
+        user_id: adminUserId,
+        date_from: new Date("2099-06-01"),
+        date_to: new Date("2099-06-03"),
+        category: "work",
+        note: `${N}A`,
+        created_by: adminUserId,
+      },
+    });
+    await prisma.work_plan_overrides.create({
+      data: {
+        user_id: adminUserId,
+        shift_date: new Date("2099-06-02"),
+        category: "leave",
+        note: `${N}B`,
+        created_by: adminUserId,
+      },
+    });
+    const cells = await resolveGrid([adminUserId], "2099-06-01", "2099-06-03");
+    expect(cells[adminUserId]["2099-06-01"]?.note).toBe(`${N}A`);
+    expect(cells[adminUserId]["2099-06-02"]?.note).toBe(`${N}B`);
+    expect(cells[adminUserId]["2099-06-03"]?.note).toBe(`${N}A`);
+  });
+});

src/services/plan.service.ts

@@ -96,3 +96,102 @@ export async function resolveCell(
     rangeTo: entry.date_to.toISOString().slice(0, 10),
   };
 }
+
+/**
+ * Compute the effective plan cell for every (userId, date) in the
+ * given range. Returns a 2D map: cells[userId][dateStr] = ResolvedCell | null.
+ *
+ * Implementation: load all entries and overrides for the range in two
+ * queries, then iterate the dates and resolve each cell in O(1) per
+ * (user, date). This avoids N+1 calls to resolveCell.
+ */
+export async function resolveGrid(
+  userIds: number[],
+  dateFromStr: string,
+  dateToStr: string,
+): Promise<Record<number, Record<string, ResolvedCell | null>>> {
+  const dateFrom = new Date(dateFromStr);
+  const dateTo = new Date(dateToStr);
+
+  const [entries, overrides] = await Promise.all([
+    prisma.work_plan_entries.findMany({
+      where: {
+        user_id: { in: userIds },
+        is_deleted: false,
+        date_from: { lte: dateTo },
+        date_to: { gte: dateFrom },
+      },
+      orderBy: { created_at: "desc" },
+    }),
+    prisma.work_plan_overrides.findMany({
+      where: {
+        user_id: { in: userIds },
+        is_deleted: false,
+        shift_date: { gte: dateFrom, lte: dateTo },
+      },
+    }),
+  ]);
+
+  // Build a date list (inclusive)
+  const dates: string[] = [];
+  for (
+    let d = new Date(dateFrom);
+    d <= dateTo;
+    d.setUTCDate(d.getUTCDate() + 1)
+  ) {
+    dates.push(d.toISOString().slice(0, 10));
+  }
+
+  const result: Record<number, Record<string, ResolvedCell | null>> = {};
+  for (const uid of userIds) {
+    result[uid] = {};
+    for (const dateStr of dates) {
+      // Override first
+      const override = overrides.find(
+        (o) =>
+          o.user_id === uid &&
+          o.shift_date.toISOString().slice(0, 10) === dateStr,
+      );
+      if (override) {
+        result[uid][dateStr] = {
+          source: "override",
+          entryId: null,
+          overrideId: override.id,
+          user_id: override.user_id,
+          shift_date: dateStr,
+          project_id: override.project_id,
+          category: override.category,
+          note: override.note,
+          rangeFrom: null,
+          rangeTo: null,
+        };
+        continue;
+      }
+      // First (latest by created_at) matching entry
+      const entry = entries.find(
+        (e) =>
+          e.user_id === uid &&
+          e.date_from <= new Date(dateStr) &&
+          e.date_to >= new Date(dateStr),
+      );
+      if (entry) {
+        result[uid][dateStr] = {
+          source: "entry",
+          entryId: entry.id,
+          overrideId: null,
+          user_id: entry.user_id,
+          shift_date: dateStr,
+          project_id: entry.project_id,
+          category: entry.category,
+          note: entry.note,
+          rangeFrom: entry.date_from.toISOString().slice(0, 10),
+          rangeTo: entry.date_to.toISOString().slice(0, 10),
+        };
+      } else {
+        result[uid][dateStr] = null;
+      }
+    }
+  }
+
+  return result;
+}