fix(ui): reject nondecimal cron repeat amounts (#107480)

* fix(ui): reject nondecimal cron repeat amounts

* fix(ui): satisfy cron LOC ratchet

* fix(ui): validate cron intervals exactly

Co-authored-by: xingzhou <zhang.guiping@xydigit.com>

* chore(pr): stage cron UI proof

Co-authored-by: xingzhou <zhang.guiping@xydigit.com>

* chore(pr): remove staged cron UI proof

Co-authored-by: xingzhou <zhang.guiping@xydigit.com>

* fix(ui): remove unused cron type export

Co-authored-by: xingzhou <zhang.guiping@xydigit.com>

---------

Co-authored-by: Peter Steinberger <steipete@gmail.com>
Co-authored-by: Peter Steinberger <peter@steipete.me>

ui/src/lib/cron/decimal.ts

@@ -0,0 +1,36 @@
+const CRON_POSITIVE_DECIMAL_RE = /^(?:\d+(?:\.\d*)?|\.\d+)$/u;
+
+const CRON_EVERY_UNIT_MS = {
+  minutes: 60_000,
+  hours: 3_600_000,
+  days: 86_400_000,
+} as const;
+
+export function parseCronEveryMs(
+  value: string,
+  unit: keyof typeof CRON_EVERY_UNIT_MS,
+): number | undefined {
+  const trimmed = value.trim();
+  if (!CRON_POSITIVE_DECIMAL_RE.test(trimmed)) {
+    return undefined;
+  }
+  const [wholePart, fractionalPart = ""] = trimmed.split(".");
+  const wholeDigits = (wholePart || "0").replace(/^0+/u, "") || "0";
+  const fractionalDigits = fractionalPart.replace(/0+$/u, "");
+  // Days contain 2^10 milliseconds, the largest base-10 scale any supported
+  // unit can cancel after trailing decimal zeroes are removed.
+  if (wholeDigits.length > String(Number.MAX_SAFE_INTEGER).length || fractionalDigits.length > 10) {
+    return undefined;
+  }
+
+  const scale = 10n ** BigInt(fractionalDigits.length);
+  const decimal = BigInt(wholeDigits) * scale + BigInt(fractionalDigits || "0");
+  const scaledMilliseconds = decimal * BigInt(CRON_EVERY_UNIT_MS[unit]);
+  if (scaledMilliseconds % scale !== 0n) {
+    return undefined;
+  }
+  const milliseconds = scaledMilliseconds / scale;
+  return milliseconds > 0n && milliseconds <= BigInt(Number.MAX_SAFE_INTEGER)
+    ? Number(milliseconds)
+    : undefined;
+}

ui/src/lib/cron/index.test.ts

@@ -1582,6 +1582,85 @@ describe("cron controller", () => {
     expect(errors.deliveryTo).toBe("cron.errors.webhookUrlInvalid");
   });
 
+  it.each(["0x10", "1e3", "+1", String(Number.MAX_SAFE_INTEGER), "0.000001"])(
+    "rejects invalid recurring amounts before submit: %s",
+    async (everyAmount) => {
+      const request = vi.fn(async (method: string) => {
+        if (method === "cron.add") {
+          return { id: "job-nondecimal" };
+        }
+        if (method === "cron.list") {
+          return { jobs: [] };
+        }
+        if (method === "cron.status") {
+          return { enabled: true, jobs: 0, nextWakeAtMs: null };
+        }
+        return {};
+      });
+      const state = createState({
+        client: { request } as unknown as CronState["client"],
+        cronForm: {
+          ...DEFAULT_CRON_FORM,
+          name: "decimal interval",
+          everyAmount,
+          payloadText: "run",
+          deliveryMode: "none",
+        },
+      });
+
+      const saved = await addCronJob(state);
+
+      expect(saved.saved).toBe(false);
+      expect(state.cronFieldErrors.everyAmount).toBe("cron.errors.everyAmountInvalid");
+      expect(request).not.toHaveBeenCalled();
+    },
+  );
+
+  it.each([
+    ["1.5", "minutes", 90_000],
+    ["4.1", "minutes", 246_000],
+    ["0.1", "hours", 360_000],
+    ["0.000125", "hours", 450],
+    ["0.1", "days", 8_640_000],
+    ["0.0009765625", "days", 84_375],
+  ] as const)(
+    "converts %s %s to safe integer milliseconds",
+    async (everyAmount, everyUnit, expectedEveryMs) => {
+      const request = vi.fn(async (method: string) => {
+        if (method === "cron.add") {
+          return { id: "job-decimal" };
+        }
+        if (method === "cron.list") {
+          return { jobs: [] };
+        }
+        if (method === "cron.status") {
+          return { enabled: true, jobs: 0, nextWakeAtMs: null };
+        }
+        return {};
+      });
+      const state = createState({
+        client: { request } as unknown as CronState["client"],
+        cronForm: {
+          ...DEFAULT_CRON_FORM,
+          name: "decimal interval",
+          everyAmount,
+          everyUnit,
+          payloadText: "run",
+          deliveryMode: "none",
+        },
+      });
+
+      const saved = await addCronJob(state);
+
+      expect(saved.saved).toBe(true);
+      const addCall = findRequestCall(request.mock.calls, "cron.add");
+      expect(requestPayload(addCall).schedule).toEqual({
+        kind: "every",
+        everyMs: expectedEveryMs,
+      });
+    },
+  );
+
   it("does not require cron expression fields for on-exit schedules", () => {
     const errors = validateCronForm({
       ...DEFAULT_CRON_FORM,

ui/src/lib/cron/index.ts

@@ -24,6 +24,7 @@ import {
   isMissingOperatorReadScopeError,
 } from "../gateway-errors.ts";
 import { normalizeLowercaseStringOrEmpty, sortUniqueStrings } from "../string-coerce.ts";
+import { parseCronEveryMs } from "./decimal.ts";
 import { loadCronFailingCount } from "./scope.ts";
 
 export { loadCronFailingCount, loadCronScopeStats } from "./scope.ts";
@@ -293,8 +294,7 @@ export function validateCronForm(form: CronFormState): CronFieldErrors {
       errors.scheduleAt = "cron.errors.scheduleAtInvalid";
     }
   } else if (form.scheduleKind === "every") {
-    const amount = toNumber(form.everyAmount, 0);
-    if (amount <= 0) {
+    if (parseCronEveryMs(form.everyAmount, form.everyUnit) === undefined) {
       errors.everyAmount = "cron.errors.everyAmountInvalid";
     }
   } else if (form.scheduleKind === "cron") {
@@ -834,13 +834,11 @@ function buildCronSchedule(form: CronFormState) {
     return { kind: "at" as const, at: new Date(ms).toISOString() };
   }
   if (form.scheduleKind === "every") {
-    const amount = toNumber(form.everyAmount, 0);
-    if (amount <= 0) {
+    const everyMs = parseCronEveryMs(form.everyAmount, form.everyUnit);
+    if (everyMs === undefined) {
       throw new Error(t("cron.errors.invalidIntervalAmount"));
     }
-    const unit = form.everyUnit;
-    const mult = unit === "minutes" ? 60_000 : unit === "hours" ? 3_600_000 : 86_400_000;
-    return { kind: "every" as const, everyMs: amount * mult };
+    return { kind: "every" as const, everyMs };
   }
   const expr = form.cronExpr.trim();
   if (!expr) {

ui/src/pages/cron/view.test.ts

@@ -618,6 +618,16 @@ describe("cron view editor", () => {
     expect(onceText).toContain("2026");
   });
 
+  it("hides the schedule summary for recurring amounts that cannot produce safe milliseconds", () => {
+    for (const everyAmount of ["0x10", "1e3", "+1", String(Number.MAX_SAFE_INTEGER), "0.000001"]) {
+      const container = renderView({
+        createOpen: true,
+        form: { ...DEFAULT_CRON_FORM, scheduleKind: "every", everyAmount },
+      });
+      expect(container.querySelector(".cron-schedule-summary")).toBeNull();
+    }
+  });
+
   it("renders supported delivery options and normalizes stale announce selection", () => {
     // systemEvent + main session cannot announce; a stale announce selection
     // must render as none and the announce option must disappear.

ui/src/pages/cron/view.ts

@@ -26,13 +26,14 @@ import "../../components/web-awesome.ts";
 import "../../components/web-awesome-popover.ts";
 import { t } from "../../i18n/index.ts";
 import { isCronJobActiveFailure, resolveCronJobLastRunStatus } from "../../lib/cron-status.ts";
+import { parseCronEveryMs } from "../../lib/cron/decimal.ts";
 import type {
   CronFieldErrors,
   CronFieldKey,
+  CronFormState,
   CronJobsLastStatusFilter,
   CronJobsScheduleKindFilter,
 } from "../../lib/cron/index.ts";
-import type { CronFormState } from "../../lib/cron/index.ts";
 import { formatRelativeTimestamp, formatMs } from "../../lib/format.ts";
 import { formatCronSchedule } from "../../lib/presenter.ts";
 import { normalizeStringEntries, uniqueStrings } from "../../lib/string-coerce.ts";
@@ -1231,12 +1232,11 @@ function renderGeneralSection(props: CronProps) {
   );
 }
 
-// Human-readable line under the schedule pills; null while inputs are invalid
-// so the summary never lies about what would be saved.
+// Human-readable schedule summary; null while invalid so it never disagrees with the saved value.
 function describeFormSchedule(form: CronFormState): string | null {
   if (form.scheduleKind === "every") {
     const amount = form.everyAmount.trim();
-    if (!amount || !Number.isFinite(Number(amount)) || Number(amount) <= 0) {
+    if (parseCronEveryMs(amount, form.everyUnit) === undefined) {
       return null;
     }
     if (Number(amount) === 1) {