Fix PocketBase date format - use YYYY-MM-DD instead of ISO

PocketBase filters don't accept ISO format with T separator (causes 400).
Changed both garmin-sync storage and today route query to use simple
YYYY-MM-DD format, matching the working /api/history pattern.

TDD approach: wrote failing tests first, then implemented the fix.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/app/api/cron/garmin-sync/route.test.ts

@@ -414,18 +414,17 @@ describe("POST /api/cron/garmin-sync", () => {
       );
     });
 
-    it("sets date to today's ISO date string", async () => {
+    it("sets date to YYYY-MM-DD format string", async () => {
       mockUsers = [createMockUser()];
-      // Full ISO format for consistent date comparison in queries
-      const todayDate = new Date();
-      todayDate.setUTCHours(0, 0, 0, 0);
-      const todayISO = todayDate.toISOString();
+      // Simple YYYY-MM-DD format for PocketBase date field compatibility
+      // PocketBase filters don't accept ISO format with T separator
+      const today = new Date().toISOString().split("T")[0];
 
       await POST(createMockRequest(`Bearer ${validSecret}`));
 
       expect(mockPbCreate).toHaveBeenCalledWith(
         expect.objectContaining({
-          date: todayISO,
+          date: today,
         }),
       );
     });

src/app/api/cron/garmin-sync/route.ts

@@ -91,13 +91,9 @@ export async function POST(request: Request) {
     (u) => u.garminConnected && u.garminTokenExpiresAt && u.lastPeriodDate,
   );
 
-  // YYYY-MM-DD format for Garmin API calls
+  // YYYY-MM-DD format for both Garmin API calls and PocketBase storage
+  // PocketBase date filters don't accept ISO format with T separator
   const today = new Date().toISOString().split("T")[0];
-  // Full ISO format for PocketBase date field storage
-  // This ensures consistent date comparison in queries
-  const todayDate = new Date();
-  todayDate.setUTCHours(0, 0, 0, 0);
-  const todayISO = todayDate.toISOString();
 
   for (const user of users) {
     const userSyncStartTime = Date.now();
@@ -214,10 +210,10 @@ export async function POST(request: Request) {
       // Store default value 100 for body battery when Garmin returns null.
       // This prevents PocketBase's number field null-to-0 coercion from
       // causing the dashboard to display 0 instead of a meaningful value.
-      // Use full ISO date format for consistent date comparison in queries
+      // Use YYYY-MM-DD format for PocketBase date field compatibility
       await pb.collection("dailyLogs").create({
         user: user.id,
-        date: todayISO,
+        date: today,
         cycleDay,
         phase,
         bodyBatteryCurrent: bodyBattery.current ?? 100,

src/app/api/today/route.test.ts

@@ -12,6 +12,9 @@ let currentMockUser: User | null = null;
 // Module-level variable to control mock daily log in tests
 let currentMockDailyLog: DailyLog | null = null;
 
+// Track the filter string passed to getFirstListItem
+let lastDailyLogFilter: string | null = null;
+
 // Create mock PocketBase client
 const mockPb = {
   collection: vi.fn((collectionName: string) => ({
@@ -30,7 +33,11 @@ const mockPb = {
       }
       throw new Error("Record not found");
     }),
-    getFirstListItem: vi.fn(async () => {
+    getFirstListItem: vi.fn(async (filter: string) => {
+      // Capture the filter for testing
+      if (collectionName === "dailyLogs") {
+        lastDailyLogFilter = filter;
+      }
       if (!currentMockDailyLog) {
         const error = new Error("No DailyLog found");
         (error as { status?: number }).status = 404;
@@ -100,6 +107,7 @@ describe("GET /api/today", () => {
     vi.clearAllMocks();
     currentMockUser = null;
     currentMockDailyLog = null;
+    lastDailyLogFilter = null;
     // Mock current date to 2025-01-10 for predictable testing
     vi.useFakeTimers();
     vi.setSystemTime(new Date("2025-01-10T12:00:00Z"));
@@ -508,6 +516,24 @@ describe("GET /api/today", () => {
     });
   });
 
+  describe("dailyLog query", () => {
+    it("queries dailyLogs with YYYY-MM-DD date format using contains operator", async () => {
+      // PocketBase filters don't accept ISO format with T separator
+      // Must use simple YYYY-MM-DD with ~ contains operator
+      currentMockUser = createMockUser();
+      currentMockDailyLog = createMockDailyLog();
+
+      await GET(mockRequest);
+
+      // Verify filter uses YYYY-MM-DD format (2025-01-10) not ISO format
+      // The filter should use ~ contains operator, not >= range
+      expect(lastDailyLogFilter).toBeDefined();
+      expect(lastDailyLogFilter).toContain('date~"2025-01-10"');
+      // Should NOT contain ISO format with T separator
+      expect(lastDailyLogFilter).not.toContain("T");
+    });
+  });
+
   describe("biometrics data", () => {
     it("returns biometrics from daily log when available", async () => {
       currentMockUser = createMockUser();

src/app/api/today/route.ts

@@ -74,24 +74,16 @@ export const GET = withAuth(async (_request, user, pb) => {
   // Sort by created DESC to get the most recent record if multiple exist
   let biometrics = { ...DEFAULT_BIOMETRICS, phaseLimit };
   try {
-    // Use date range query for proper date field comparison
-    // PocketBase date fields need >= and < operators, not string contains
-    const todayStart = new Date();
-    todayStart.setUTCHours(0, 0, 0, 0);
-    const tomorrowStart = new Date(todayStart.getTime() + 86400000);
-    const todayISO = todayStart.toISOString();
-    const tomorrowISO = tomorrowStart.toISOString();
+    // Use YYYY-MM-DD format with contains operator for PocketBase date field
+    // PocketBase filters don't accept ISO format with T separator
+    const today = new Date().toISOString().split("T")[0];
 
-    logger.info(
-      { userId: user.id, todayISO, tomorrowISO },
-      "Fetching dailyLog",
-    );
+    logger.info({ userId: user.id, date: today }, "Fetching dailyLog");
     const dailyLog = await pb
       .collection("dailyLogs")
-      .getFirstListItem<DailyLog>(
-        `user="${user.id}" && date>="${todayISO}" && date<"${tomorrowISO}"`,
-        { sort: "-created" },
-      );
+      .getFirstListItem<DailyLog>(`user="${user.id}" && date~"${today}"`, {
+        sort: "-created",
+      });
 
     logger.info(
       {