fix(work-orders): sync search page when the result set shrinks

src/app/(protected)/workorders/_hooks/use-sync-out-of-range-search-page.ts

@@ -0,0 +1,24 @@
+import { useEffect } from "react";
+import { nextSearchPageIfOutOfRange } from "@/domain/work-orders/utils/day-pagination";
+
+type UseSyncOutOfRangeSearchPageInput = {
+  enabled: boolean;
+  ready: boolean;
+  page: number;
+  pageSize: number;
+  totalCount: number;
+  setPage: (page: number) => void;
+};
+
+/** Keeps the requested search page inside the last valid page after the result set shrinks. */
+export function useSyncOutOfRangeSearchPage(input: UseSyncOutOfRangeSearchPageInput) {
+  const { enabled, ready, page, pageSize, totalCount, setPage } = input;
+  const nextPage = nextSearchPageIfOutOfRange({ page, pageSize, totalCount });
+
+  useEffect(() => {
+    if (!enabled || !ready || nextPage == null) {
+      return;
+    }
+    setPage(nextPage);
+  }, [enabled, ready, nextPage, setPage]);
+}

src/app/(protected)/workorders/_hooks/use-work-orders-table-data.ts

@@ -1,5 +1,6 @@
 import { useMemo } from "react";
 import type { useWorkOrdersListFilters } from "@/app/(protected)/workorders/_hooks/use-work-orders-list-filters";
+import { useSyncOutOfRangeSearchPage } from "@/app/(protected)/workorders/_hooks/use-sync-out-of-range-search-page";
 import { useWorkOrdersBoardSource } from "@/app/(protected)/workorders/_hooks/use-work-orders-board-source";
 import { useWorkOrdersDayPagination } from "@/app/(protected)/workorders/_hooks/use-work-orders-day-pagination";
 import { useWorkOrdersTableLocalState } from "@/app/(protected)/workorders/_hooks/use-work-orders-table-local-state";
@@ -104,6 +105,14 @@ export function useWorkOrdersTableData(filters: FiltersReturn) {
   );
 
   const scopeTotalCount = advActive ? (data?.totalCount ?? advResults.length) : dayTotalCount;
+  useSyncOutOfRangeSearchPage({
+    enabled: advActive,
+    ready: !isLoading,
+    page: filters.page,
+    pageSize: filters.pageSize,
+    totalCount: scopeTotalCount,
+    setPage: filters.setPage,
+  });
   const listTotalCount = advActive ? advResults.length : dayVisibleCount;
   const pager = pickBoardPager({
     advActive,

src/domain/work-orders/utils/day-pagination.ts

@@ -91,6 +91,21 @@ export function resolveSearchPager(input: { page: number; pageSize: number; tota
   };
 }
 
+export function nextSearchPageIfOutOfRange(input: {
+  page: number;
+  pageSize: number;
+  totalCount: number;
+}): number | null {
+  if (input.totalCount <= 0) {
+    return null;
+  }
+  const pageCount = totalPageCount(input.totalCount, asDayPageSize(input.pageSize));
+  if (input.page < pageCount) {
+    return null;
+  }
+  return pageCount - 1;
+}
+
 export function pickBoardPager(input: {
   advActive: boolean;
   isLoading: boolean;

src/test/app/(protected)/workorders/use-sync-out-of-range-search-page.test.tsx

@@ -0,0 +1,50 @@
+import { renderHook } from "@testing-library/react";
+import { describe, expect, it, vi } from "vitest";
+import { useSyncOutOfRangeSearchPage } from "@/app/(protected)/workorders/_hooks/use-sync-out-of-range-search-page";
+
+describe("useSyncOutOfRangeSearchPage", () => {
+  it("sets the last valid page when a search shrinks to one page", () => {
+    const setPage = vi.fn();
+    renderHook(() =>
+      useSyncOutOfRangeSearchPage({
+        enabled: true,
+        ready: true,
+        page: 1,
+        pageSize: 50,
+        totalCount: 40,
+        setPage,
+      }),
+    );
+    expect(setPage).toHaveBeenCalledWith(0);
+  });
+
+  it("does not sync while the search query is loading", () => {
+    const setPage = vi.fn();
+    renderHook(() =>
+      useSyncOutOfRangeSearchPage({
+        enabled: true,
+        ready: false,
+        page: 1,
+        pageSize: 50,
+        totalCount: 40,
+        setPage,
+      }),
+    );
+    expect(setPage).not.toHaveBeenCalled();
+  });
+
+  it("does not sync when the result set is empty", () => {
+    const setPage = vi.fn();
+    renderHook(() =>
+      useSyncOutOfRangeSearchPage({
+        enabled: true,
+        ready: true,
+        page: 1,
+        pageSize: 50,
+        totalCount: 0,
+        setPage,
+      }),
+    );
+    expect(setPage).not.toHaveBeenCalled();
+  });
+});

src/test/domain/work-orders/utils/day-pagination.test.ts

@@ -5,6 +5,7 @@ import {
   asDayPageSize,
   findItemPageIndex,
   formatDayPaginationSummary,
+  nextSearchPageIfOutOfRange,
   pageIndexForItem,
   paginateItems,
   pickBoardPager,
@@ -137,3 +138,21 @@ describe("day pagination utils (SH-241)", () => {
     expect(formatDayPaginationSummary("Tue · 06/02", 1)).toBe("TUE · 06/02 · 1 item");
   });
 });
+
+describe("nextSearchPageIfOutOfRange", () => {
+  it("returns the last valid page when a search shrinks to one page", () => {
+    expect(nextSearchPageIfOutOfRange({ page: 1, pageSize: 50, totalCount: 40 })).toBe(0);
+  });
+
+  it("leaves a still-valid second page alone", () => {
+    expect(nextSearchPageIfOutOfRange({ page: 1, pageSize: 50, totalCount: 60 })).toBeNull();
+  });
+
+  it("does not pull an empty result set onto page 1", () => {
+    expect(nextSearchPageIfOutOfRange({ page: 1, pageSize: 50, totalCount: 0 })).toBeNull();
+  });
+
+  it("leaves the last valid page alone", () => {
+    expect(nextSearchPageIfOutOfRange({ page: 0, pageSize: 50, totalCount: 40 })).toBeNull();
+  });
+});