feat(pin-model): add aggregateDriverStatus helper (TDD)

src/app/(app)/collection-map/pin-model.ts

@@ -48,3 +48,41 @@ export function splitSupplierBucket<
   }
   return { assignedByDriver, poolItems };
 }
+
+export interface DriverStatus {
+  total: number;
+  collected: number;
+  ready: number;
+  waiting: number;
+}
+
+/**
+ * Counts a driver's stops into the four buckets the driver card surfaces:
+ *   - collected : item_status === "collected" (the green anchor)
+ *   - ready     : ready_for_collection === true and not collected
+ *   - waiting   : ready_for_collection !== true and not collected
+ *   - total     : items.length
+ *
+ * Items with `ready_for_collection` undefined or null are treated as
+ * not ready (waiting). Pure — no DB / side effects.
+ */
+export function aggregateDriverStatus<
+  T extends {
+    item_status: string;
+    ready_for_collection?: boolean | null;
+  }
+>(items: T[]): DriverStatus {
+  let collected = 0;
+  let ready = 0;
+  let waiting = 0;
+  for (const it of items) {
+    if (it.item_status === "collected") {
+      collected++;
+    } else if (it.ready_for_collection) {
+      ready++;
+    } else {
+      waiting++;
+    }
+  }
+  return { total: items.length, collected, ready, waiting };
+}

src/lib/pin-model.test.ts

@@ -0,0 +1,78 @@
+import { describe, expect, it } from "vitest";
+import { aggregateDriverStatus } from "@/app/(app)/collection-map/pin-model";
+
+describe("aggregateDriverStatus", () => {
+  it("returns zeros for an empty array", () => {
+    expect(aggregateDriverStatus([])).toEqual({
+      total: 0,
+      collected: 0,
+      ready: 0,
+      waiting: 0,
+    });
+  });
+
+  it("counts every item as collected when every item is collected", () => {
+    const items = [
+      { item_status: "collected" as const, ready_for_collection: true },
+      { item_status: "collected" as const, ready_for_collection: true },
+      { item_status: "collected" as const, ready_for_collection: false },
+    ];
+    expect(aggregateDriverStatus(items)).toEqual({
+      total: 3,
+      collected: 3,
+      ready: 0,
+      waiting: 0,
+    });
+  });
+
+  it("counts every item as waiting when nothing is ready or collected", () => {
+    const items = [
+      { item_status: "collection_pool" as const, ready_for_collection: false },
+      { item_status: "assigned" as const, ready_for_collection: false },
+    ];
+    expect(aggregateDriverStatus(items)).toEqual({
+      total: 2,
+      collected: 0,
+      ready: 0,
+      waiting: 2,
+    });
+  });
+
+  it("rolls up mixed states (collected + ready + waiting)", () => {
+    const items = [
+      { item_status: "collected" as const, ready_for_collection: true },
+      { item_status: "collected" as const, ready_for_collection: true },
+      { item_status: "assigned" as const, ready_for_collection: true },
+      { item_status: "assigned" as const, ready_for_collection: true },
+      { item_status: "assigned" as const, ready_for_collection: true },
+      { item_status: "collection_pool" as const, ready_for_collection: false },
+    ];
+    expect(aggregateDriverStatus(items)).toEqual({
+      total: 6,
+      collected: 2,
+      ready: 3,
+      waiting: 1,
+    });
+  });
+
+  it("treats undefined ready_for_collection as waiting", () => {
+    const items = [
+      { item_status: "assigned" as const },
+      { item_status: "collection_pool" as const },
+    ];
+    expect(aggregateDriverStatus(items).waiting).toBe(2);
+    expect(aggregateDriverStatus(items).ready).toBe(0);
+    expect(aggregateDriverStatus(items).collected).toBe(0);
+    expect(aggregateDriverStatus(items).total).toBe(2);
+  });
+
+  it("treats null ready_for_collection as waiting", () => {
+    const items = [
+      { item_status: "assigned" as const, ready_for_collection: null },
+      { item_status: "collection_pool" as const, ready_for_collection: null },
+    ];
+    expect(aggregateDriverStatus(items).waiting).toBe(2);
+    expect(aggregateDriverStatus(items).ready).toBe(0);
+    expect(aggregateDriverStatus(items).collected).toBe(0);
+  });
+});