geofence refinement

and manual failsafe

apps/admin/src/app/api/attendance/__tests__/attendance.test.ts

@@ -38,6 +38,8 @@ jest.mock("@/lib/geofence", () => ({
     accuracy: 10,
   })),
   validateGeofence: jest.fn(() => ({ ok: true })),
+  validateGeofenceWithFallback: jest.fn(() => ({ ok: true })),
+  validateCheckInGeofence: jest.fn(() => ({ ok: true })),
 }));
 
 const mockDb = {

apps/admin/src/app/api/attendance/check-in/route.ts

@@ -5,7 +5,7 @@ import { ensureUserSynced } from "@/lib/sync-user";
 import {
   getUserGymGeofence,
   parseUserLocation,
-  validateGeofence,
+  validateCheckInGeofence,
 } from "@/lib/geofence";
 import log from "@/lib/logger";
 
@@ -27,6 +27,7 @@ export async function POST(req: NextRequest) {
 
     const body = await req.json().catch(() => ({}));
     const { type = "gym", notes } = body;
+    const fallbackRequested = Boolean(body.fallbackRequested);
 
     const gym = await getUserGymGeofence(userId);
     if (!gym) {
@@ -37,7 +38,7 @@ export async function POST(req: NextRequest) {
     }
 
     const location = parseUserLocation(body.location);
-    const geofence = validateGeofence(gym, location);
+    const geofence = validateCheckInGeofence(gym, location, fallbackRequested);
     if (!geofence.ok) {
       return NextResponse.json(
         { error: geofence.error },

apps/admin/src/app/api/attendance/check-out/route.ts

@@ -4,7 +4,7 @@ import { getDatabase } from "@/lib/database";
 import {
   getUserGymGeofence,
   parseUserLocation,
-  validateGeofence,
+  validateGeofenceWithFallback,
 } from "@/lib/geofence";
 import log from "@/lib/logger";
 
@@ -21,6 +21,7 @@ export async function POST(req: Request) {
     }
 
     const body = await req.json().catch(() => ({}));
+    const fallbackRequested = Boolean(body.fallbackRequested);
 
     const gym = await getUserGymGeofence(userId);
     if (!gym) {
@@ -31,7 +32,11 @@ export async function POST(req: Request) {
     }
 
     const location = parseUserLocation(body.location);
-    const geofence = validateGeofence(gym, location);
+    const geofence = validateGeofenceWithFallback(
+      gym,
+      location,
+      fallbackRequested,
+    );
     if (!geofence.ok) {
       return NextResponse.json(
         { error: geofence.error },

apps/admin/src/app/api/users/gym/route.ts

@@ -1,8 +1,78 @@
 import { NextResponse } from "next/server";
 import { auth } from "@clerk/nextjs/server";
 import { db, users as usersTable, eq, sql } from "@fitai/database";
+import { ensureGymsGeofenceColumns } from "@/lib/geofence";
 import log from "@/lib/logger";
 
+export async function GET() {
+  try {
+    const { userId } = await auth();
+    if (!userId) return new NextResponse("Unauthorized", { status: 401 });
+
+    const user = await db
+      .select()
+      .from(usersTable)
+      .where(eq(usersTable.id, userId))
+      .get();
+
+    if (!user) {
+      return new NextResponse("User not found", { status: 404 });
+    }
+
+    if (!user.gymId) {
+      return NextResponse.json({ gymId: null, gym: null });
+    }
+
+    await ensureGymsGeofenceColumns();
+
+    const rows = await db.all(sql`
+      SELECT
+        id,
+        name,
+        location,
+        latitude,
+        longitude,
+        geofence_radius_meters as geofenceRadiusMeters,
+        geofence_enabled as geofenceEnabled,
+        status
+      FROM gyms
+      WHERE id = ${user.gymId}
+      LIMIT 1
+    `);
+
+    const gym = rows?.[0] as
+      | {
+          id: string;
+          name: string;
+          location: string | null;
+          latitude: number | null;
+          longitude: number | null;
+          geofenceRadiusMeters: number | null;
+          geofenceEnabled: number | boolean | null;
+          status: "active" | "inactive";
+        }
+      | undefined;
+
+    if (!gym || gym.status !== "active") {
+      return NextResponse.json({ gymId: user.gymId, gym: null });
+    }
+
+    return NextResponse.json({
+      gymId: user.gymId,
+      gym: {
+        ...gym,
+        geofenceEnabled:
+          typeof gym.geofenceEnabled === "boolean"
+            ? gym.geofenceEnabled
+            : Boolean(gym.geofenceEnabled),
+      },
+    });
+  } catch (error) {
+    log.error("Failed to fetch current user gym", error);
+    return new NextResponse("Internal Server Error", { status: 500 });
+  }
+}
+
 /**
  * PATCH /api/users/gym
  * Body: { gymId: string | null }

apps/admin/src/lib/geofence.ts

@@ -2,6 +2,7 @@ import { db, eq, sql, users } from "@fitai/database";
 
 export const DEFAULT_GEOFENCE_RADIUS_METERS = 30;
 export const MAX_LOCATION_ACCURACY_METERS = 50;
+export const MAX_FALLBACK_ACCURACY_MARGIN_METERS = 120;
 
 export interface UserLocation {
   latitude: number;
@@ -169,6 +170,85 @@ export function validateGeofence(
   return { ok: true };
 }
 
+export function validateGeofenceWithFallback(
+  gym: GymGeofenceConfig,
+  location: UserLocation | null,
+  fallbackRequested: boolean,
+): { ok: true } | { ok: false; status: number; error: string } {
+  const geofenceEnabled = gym.geofenceEnabled ?? true;
+  if (!geofenceEnabled) {
+    return { ok: true };
+  }
+
+  if (!location) {
+    return {
+      ok: false,
+      status: 400,
+      error: "Location is required for gym check-in/check-out",
+    };
+  }
+
+  if (gym.latitude === null || gym.longitude === null) {
+    return {
+      ok: false,
+      status: 400,
+      error: "Gym geofence is enabled but gym coordinates are not configured",
+    };
+  }
+
+  const radius = gym.geofenceRadiusMeters ?? DEFAULT_GEOFENCE_RADIUS_METERS;
+  const distanceMeters = haversineDistanceMeters(
+    gym.latitude,
+    gym.longitude,
+    location.latitude,
+    location.longitude,
+  );
+
+  if (location.accuracy <= MAX_LOCATION_ACCURACY_METERS) {
+    if (distanceMeters > radius) {
+      return {
+        ok: false,
+        status: 403,
+        error: `You are outside the gym geofence (${Math.round(distanceMeters)}m away, allowed ${Math.round(radius)}m).`,
+      };
+    }
+
+    return { ok: true };
+  }
+
+  if (!fallbackRequested) {
+    return {
+      ok: false,
+      status: 400,
+      error: `Location accuracy too low (${Math.round(location.accuracy)}m). Move to an open area and try again.`,
+    };
+  }
+
+  const fallbackMargin = Math.min(
+    location.accuracy,
+    MAX_FALLBACK_ACCURACY_MARGIN_METERS,
+  );
+  const fallbackAllowedDistance = radius + fallbackMargin;
+
+  if (distanceMeters > fallbackAllowedDistance) {
+    return {
+      ok: false,
+      status: 403,
+      error: `You are outside the gym geofence (${Math.round(distanceMeters)}m away, fallback allowed ${Math.round(fallbackAllowedDistance)}m).`,
+    };
+  }
+
+  return { ok: true };
+}
+
+export function validateCheckInGeofence(
+  gym: GymGeofenceConfig,
+  location: UserLocation | null,
+  fallbackRequested: boolean,
+): { ok: true } | { ok: false; status: number; error: string } {
+  return validateGeofenceWithFallback(gym, location, fallbackRequested);
+}
+
 function haversineDistanceMeters(
   latitude1: number,
   longitude1: number,

apps/mobile/app.json

@@ -18,7 +18,12 @@
         "NSCameraUsageDescription": "This app uses the camera to scan food barcodes and identify nutritional information.",
         "NSUserNotificationsUsageDescription": "This app uses notifications to keep you updated on your fitness progress, recommendation approvals, and important reminders.",
         "NSMotionUsageDescription": "This app uses motion data to track your daily steps and activity progress.",
-        "NSLocationWhenInUseUsageDescription": "This app uses your location to verify you are at your gym when checking in and checking out."
+        "NSLocationWhenInUseUsageDescription": "This app uses your location to verify you are at your gym when checking in and checking out.",
+        "NSLocationAlwaysAndWhenInUseUsageDescription": "This app uses your location in the background to automatically start and end workouts when you enter or leave your gym geofence."
+      },
+      "bundleIdentifier": "com.anonymous.fitai",
+      "config": {
+        "usesNonExemptEncryption": false
       }
     },
     "android": {
@@ -32,7 +37,8 @@
         "android.permission.CAMERA",
         "android.permission.ACTIVITY_RECOGNITION",
         "android.permission.ACCESS_FINE_LOCATION",
-        "android.permission.ACCESS_COARSE_LOCATION"
+        "android.permission.ACCESS_COARSE_LOCATION",
+        "android.permission.ACCESS_BACKGROUND_LOCATION"
       ],
       "package": "com.anonymous.fitai"
     },
@@ -43,7 +49,15 @@
       "expo-router",
       "expo-font",
       "expo-barcode-scanner",
-      "expo-location",
+      [
+        "expo-location",
+        {
+          "locationWhenInUsePermission": "Allow FitAI to use your location to verify gym check-ins and check-outs.",
+          "locationAlwaysAndWhenInUsePermission": "Allow FitAI to use your location in the background to automatically start and end workouts at your gym.",
+          "isIosBackgroundLocationEnabled": true,
+          "isAndroidBackgroundLocationEnabled": true
+        }
+      ],
       [
         "expo-notifications",
         {

apps/mobile/package-lock.json

@@ -35,6 +35,7 @@
         "expo-secure-store": "~15.0.7",
         "expo-sensors": "~14.1.4",
         "expo-status-bar": "^3.0.8",
+        "expo-task-manager": "~14.0.8",
         "expo-web-browser": "^15.0.10",
         "react": "19.1.0",
         "react-dom": "^19.1.0",
@@ -7650,6 +7651,19 @@
         "react-native": "*"
       }
     },
+    "node_modules/expo-task-manager": {
+      "version": "14.0.9",
+      "resolved": "https://registry.npmjs.org/expo-task-manager/-/expo-task-manager-14.0.9.tgz",
+      "integrity": "sha512-GKWtXrkedr4XChHfTm5IyTcSfMtCPxzx89y4CMVqKfyfROATibrE/8UI5j7UC/pUOfFoYlQvulQEvECMreYuUA==",
+      "license": "MIT",
+      "dependencies": {
+        "unimodules-app-loader": "~6.0.8"
+      },
+      "peerDependencies": {
+        "expo": "*",
+        "react-native": "*"
+      }
+    },
     "node_modules/expo-web-browser": {
       "version": "15.0.10",
       "resolved": "https://registry.npmjs.org/expo-web-browser/-/expo-web-browser-15.0.10.tgz",
@@ -13443,6 +13457,12 @@
         "node": ">=4"
       }
     },
+    "node_modules/unimodules-app-loader": {
+      "version": "6.0.8",
+      "resolved": "https://registry.npmjs.org/unimodules-app-loader/-/unimodules-app-loader-6.0.8.tgz",
+      "integrity": "sha512-fqS8QwT/MC/HAmw1NKCHdzsPA6WaLm0dNmoC5Pz6lL+cDGYeYCNdHMO9fy08aL2ZD7cVkNM0pSR/AoNRe+rslA==",
+      "license": "MIT"
+    },
     "node_modules/unique-string": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/unique-string/-/unique-string-2.0.0.tgz",

apps/mobile/package.json

@@ -38,6 +38,7 @@
     "expo-location": "~19.0.7",
     "expo-notifications": "~0.32.0",
     "expo-router": "~6.0.14",
+    "expo-task-manager": "~14.0.8",
     "expo-secure-store": "~15.0.7",
     "expo-sensors": "~14.1.4",
     "expo-status-bar": "^3.0.8",

apps/mobile/src/api/attendance.ts

@@ -1,5 +1,6 @@
 import { apiClient } from "./client";
 import { API_ENDPOINTS } from "../config/api";
+import { isAxiosError } from "axios";
 
 export interface Attendance {
   id: string;
@@ -23,7 +24,9 @@ export const attendanceApi = {
       });
       return response.data;
     } catch (error) {
-      throw error;
+      throw new Error(
+        getAttendanceErrorMessage(error, "Failed to load attendance history."),
+      );
     }
   },
 
@@ -31,30 +34,55 @@ export const attendanceApi = {
     type: string,
     token: string,
     location: AttendanceLocationPayload,
+    fallbackRequested = false,
   ): Promise<void> => {
     try {
       await apiClient.post(
         API_ENDPOINTS.ATTENDANCE.CHECK_IN,
-        { type, location },
+        { type, location, fallbackRequested },
         { headers: { Authorization: `Bearer ${token}` } },
       );
     } catch (error) {
-      throw error;
+      throw new Error(
+        getAttendanceErrorMessage(error, "Failed to start workout."),
+      );
     }
   },
 
   checkOut: async (
     token: string,
     location: AttendanceLocationPayload,
+    fallbackRequested = false,
   ): Promise<void> => {
     try {
       await apiClient.post(
         API_ENDPOINTS.ATTENDANCE.CHECK_OUT,
-        { location },
+        { location, fallbackRequested },
         { headers: { Authorization: `Bearer ${token}` } },
       );
     } catch (error) {
-      throw error;
+      throw new Error(
+        getAttendanceErrorMessage(error, "Failed to end workout."),
+      );
     }
   },
 };
+
+function getAttendanceErrorMessage(error: unknown, fallback: string): string {
+  if (isAxiosError(error)) {
+    const payload = error.response?.data;
+
+    if (typeof payload === "string" && payload.trim()) {
+      return payload;
+    }
+
+    if (payload && typeof payload === "object") {
+      const message = (payload as { error?: unknown }).error;
+      if (typeof message === "string" && message.trim()) {
+        return message;
+      }
+    }
+  }
+
+  return fallback;
+}

apps/mobile/src/api/userGym.ts

@@ -0,0 +1,28 @@
+import { API_ENDPOINTS } from "../config/api";
+import { apiClient, withAuth } from "./client";
+
+export interface UserGymGeofence {
+  id: string;
+  name: string;
+  location: string | null;
+  latitude: number | null;
+  longitude: number | null;
+  geofenceRadiusMeters: number | null;
+  geofenceEnabled: boolean;
+  status: "active" | "inactive";
+}
+
+export interface UserGymResponse {
+  gymId: string | null;
+  gym: UserGymGeofence | null;
+}
+
+export const userGymApi = {
+  getCurrentGym: async (token: string | null): Promise<UserGymResponse> => {
+    const response = await apiClient.get<UserGymResponse>(
+      API_ENDPOINTS.USERS.GYM,
+      withAuth(token),
+    );
+    return response.data;
+  },
+};

apps/mobile/src/app/(auth)/onboarding.tsx

@@ -17,6 +17,7 @@ import { useTheme } from "../../contexts/ThemeContext";
 import { Input } from "../../components/Input";
 import { MinimalButton } from "../../components/MinimalButton";
 import { MinimalCard } from "../../components/MinimalCard";
+import { syncAutoWorkoutGeofenceWithToken } from "../../services/autoWorkoutGeofence";
 import log from "../../utils/logger";
 
 export default function OnboardingScreen() {
@@ -81,6 +82,9 @@ export default function OnboardingScreen() {
       // selectedGymId: string gym id, or null to proceed without gym
       try {
         await gymsApi.updateUserGym(selectedGymId, token);
+        await syncAutoWorkoutGeofenceWithToken(token, {
+          requestPermissions: true,
+        });
       } catch (e) {
         log.warn("Failed to update gym selection", { gymId: selectedGymId });
       }

apps/mobile/src/app/(tabs)/index.tsx

@@ -30,6 +30,7 @@ import { ActivityRing } from "../../components/ActivityRing";
 import { useMembership } from "../../hooks/useMembership";
 import { attendanceApi, type Attendance } from "../../api/attendance";
 import { useDailySteps } from "../../hooks/useDailySteps";
+import { syncAutoWorkoutGeofenceWithToken } from "../../services/autoWorkoutGeofence";
 import {
   checkInsToActivities,
   completedGoalsToActivities,
@@ -237,6 +238,10 @@ export default function HomeScreen() {
         return;
       }
 
+      await syncAutoWorkoutGeofenceWithToken(token, {
+        requestPermissions: true,
+      });
+
       const permission = await Location.requestForegroundPermissionsAsync();
       if (permission.status !== "granted") {
         Alert.alert(
@@ -256,10 +261,17 @@ export default function HomeScreen() {
       };
 
       if (activeWorkoutSession) {
-        await attendanceApi.checkOut(token, locationPayload);
+        const fallbackRequested = locationPayload.accuracy > 50;
+        await attendanceApi.checkOut(token, locationPayload, fallbackRequested);
         Alert.alert("Workout logged", "Session ended successfully.");
       } else {
-        await attendanceApi.checkIn("gym", token, locationPayload);
+        const fallbackRequested = locationPayload.accuracy > 50;
+        await attendanceApi.checkIn(
+          "gym",
+          token,
+          locationPayload,
+          fallbackRequested,
+        );
         Alert.alert("Workout started", "Session started successfully.");
       }
 

apps/mobile/src/app/(tabs)/profile.tsx

@@ -21,6 +21,7 @@ import { IconContainer } from "../../components/IconContainer";
 import { fitnessProfileApi, FitnessProfile } from "../../api/fitnessProfile";
 import { gymsApi, type Gym } from "../../api/gyms";
 import { useMembership } from "../../hooks/useMembership";
+import { syncAutoWorkoutGeofenceWithToken } from "../../services/autoWorkoutGeofence";
 import log from "../../utils/logger";
 
 export default function ProfileScreen() {
@@ -115,6 +116,12 @@ export default function ProfileScreen() {
         "Success",
         selectedGymId ? "Gym selected successfully" : "Proceeding without gym",
       );
+
+      if (token) {
+        await syncAutoWorkoutGeofenceWithToken(token, {
+          requestPermissions: true,
+        });
+      }
     } catch (err) {
       log.error("Failed to update gym selection", err);
       Alert.alert("Error", "Failed to update gym selection");

apps/mobile/src/app/_layout.tsx

@@ -13,6 +13,7 @@ import { RecommendationsProvider } from "../contexts/RecommendationsContext";
 import { NotificationsProvider } from "../contexts/NotificationsContext";
 import { MembershipProvider } from "../contexts/MembershipContext";
 import { queryClient } from "../lib/query-client";
+import { useAutoWorkoutGeofence } from "../hooks/useAutoWorkoutGeofence";
 import log from "../utils/logger";
 
 // Wrapper to use notification permissions hook after ClerkLoaded
@@ -22,6 +23,7 @@ function AppContent() {
     useNotificationPermissions,
   } = require("../hooks/useNotificationPermissions");
   useNotificationPermissions();
+  useAutoWorkoutGeofence();
 
   return (
     <Stack>

apps/mobile/src/hooks/useAutoWorkoutGeofence.ts

@@ -0,0 +1,68 @@
+import { useAuth } from "@clerk/clerk-expo";
+import { useCallback, useEffect } from "react";
+import { AppState } from "react-native";
+import {
+  disableAutoWorkoutGeofence,
+  syncAutoWorkoutGeofenceWithToken,
+} from "../services/autoWorkoutGeofence";
+import log from "../utils/logger";
+
+export function useAutoWorkoutGeofence() {
+  const { isSignedIn, getToken } = useAuth();
+
+  const syncGeofence = useCallback(async () => {
+    try {
+      if (!isSignedIn) {
+        await disableAutoWorkoutGeofence();
+        return;
+      }
+
+      const token = await getToken();
+      if (!token) {
+        await disableAutoWorkoutGeofence();
+        return;
+      }
+
+      await syncAutoWorkoutGeofenceWithToken(token, {
+        requestPermissions: true,
+      });
+    } catch (error) {
+      log.warn("Failed to sync auto workout geofence", {
+        error: error instanceof Error ? error.message : String(error),
+      });
+    }
+  }, [getToken, isSignedIn]);
+
+  useEffect(() => {
+    void syncGeofence();
+  }, [syncGeofence]);
+
+  useEffect(() => {
+    const appStateSubscription = AppState.addEventListener(
+      "change",
+      (state) => {
+        if (state === "active") {
+          void syncGeofence();
+        }
+      },
+    );
+
+    const interval = setInterval(
+      () => {
+        void syncGeofence();
+      },
+      5 * 60 * 1000,
+    );
+
+    return () => {
+      appStateSubscription.remove();
+      clearInterval(interval);
+    };
+  }, [syncGeofence]);
+
+  useEffect(() => {
+    if (!isSignedIn) {
+      void disableAutoWorkoutGeofence();
+    }
+  }, [isSignedIn]);
+}

apps/mobile/src/lib/background-auth-token.ts

@@ -0,0 +1,19 @@
+import * as SecureStore from "expo-secure-store";
+
+const BACKGROUND_AUTH_TOKEN_KEY = "fitai_background_auth_token";
+
+export async function saveBackgroundAuthToken(token: string): Promise<void> {
+  if (!looksLikeJwt(token)) {
+    return;
+  }
+
+  await SecureStore.setItemAsync(BACKGROUND_AUTH_TOKEN_KEY, token);
+}
+
+export async function getBackgroundAuthToken(): Promise<string | null> {
+  return SecureStore.getItemAsync(BACKGROUND_AUTH_TOKEN_KEY);
+}
+
+function looksLikeJwt(token: string): boolean {
+  return token.split(".").length === 3;
+}

apps/mobile/src/services/autoWorkoutGeofence.ts

@@ -0,0 +1,296 @@
+import * as Location from "expo-location";
+import * as TaskManager from "expo-task-manager";
+import { apiClient } from "../api/client";
+import { userGymApi } from "../api/userGym";
+import { API_ENDPOINTS } from "../config/api";
+import { saveBackgroundAuthToken } from "../lib/background-auth-token";
+import { getBackgroundAuthToken } from "../lib/background-auth-token";
+import log from "../utils/logger";
+
+const AUTO_WORKOUT_GEOFENCE_TASK = "fitai-auto-workout-geofence";
+const DEFAULT_RADIUS_METERS = 30;
+const MAX_ACCEPTABLE_ACCURACY_METERS = 50;
+const ACTION_COOLDOWN_MS = 90_000;
+
+let lastActionAt = 0;
+
+interface GeofenceRegion {
+  identifier: string;
+  latitude: number;
+  longitude: number;
+  radius: number;
+  notifyOnEnter: boolean;
+  notifyOnExit: boolean;
+}
+
+if (!TaskManager.isTaskDefined(AUTO_WORKOUT_GEOFENCE_TASK)) {
+  TaskManager.defineTask(
+    AUTO_WORKOUT_GEOFENCE_TASK,
+    async ({ data, error }: TaskManager.TaskManagerTaskBody) => {
+      if (error) {
+        log.error("Auto workout geofence task failed", error);
+        return;
+      }
+
+      const event = data as
+        | {
+            eventType?: Location.GeofencingEventType;
+            region?: GeofenceRegion;
+          }
+        | undefined;
+
+      const eventType = event?.eventType;
+      if (
+        eventType !== Location.GeofencingEventType.Enter &&
+        eventType !== Location.GeofencingEventType.Exit
+      ) {
+        return;
+      }
+
+      const now = Date.now();
+      if (now - lastActionAt < ACTION_COOLDOWN_MS) {
+        return;
+      }
+      lastActionAt = now;
+
+      try {
+        const token = await getBackgroundAuthToken();
+        if (!token) {
+          log.warn("Skipping geofence auto-workout due to missing auth token");
+          return;
+        }
+
+        const location = await Location.getCurrentPositionAsync({
+          accuracy: Location.Accuracy.Balanced,
+        });
+
+        const accuracy = location.coords.accuracy ?? 999;
+        if (accuracy > MAX_ACCEPTABLE_ACCURACY_METERS) {
+          log.warn("Skipping geofence auto-workout due to poor GPS accuracy", {
+            accuracy,
+          });
+          return;
+        }
+
+        const headers = { Authorization: `Bearer ${token}` };
+        const locationPayload = {
+          latitude: location.coords.latitude,
+          longitude: location.coords.longitude,
+          accuracy,
+        };
+
+        const historyRes = await apiClient.get(
+          API_ENDPOINTS.ATTENDANCE.HISTORY,
+          {
+            headers,
+          },
+        );
+        const history = Array.isArray(historyRes.data)
+          ? (historyRes.data as Array<{ id: string; checkOutTime?: string }>)
+          : [];
+        const activeSession = history.find((item) => !item.checkOutTime);
+
+        if (eventType === Location.GeofencingEventType.Enter) {
+          if (activeSession) {
+            return;
+          }
+
+          await apiClient.post(
+            API_ENDPOINTS.ATTENDANCE.CHECK_IN,
+            { type: "gym", location: locationPayload },
+            { headers },
+          );
+          log.info("Auto-started workout after geofence enter");
+          return;
+        }
+
+        if (!activeSession) {
+          return;
+        }
+
+        await apiClient.post(
+          API_ENDPOINTS.ATTENDANCE.CHECK_OUT,
+          {
+            location: locationPayload,
+            fallbackRequested: accuracy > MAX_ACCEPTABLE_ACCURACY_METERS,
+          },
+          { headers },
+        );
+        log.info("Auto-ended workout after geofence exit");
+      } catch (taskError: unknown) {
+        if (
+          isApiError(taskError, 400, "Already checked in") ||
+          isApiError(taskError, 404, "No active check-in found")
+        ) {
+          return;
+        }
+
+        log.error("Auto workout geofence action failed", taskError);
+      }
+    },
+  );
+}
+
+export async function configureAutoWorkoutGeofence(params: {
+  latitude: number;
+  longitude: number;
+  radiusMeters?: number | null;
+}): Promise<void> {
+  const started = await Location.hasStartedGeofencingAsync(
+    AUTO_WORKOUT_GEOFENCE_TASK,
+  );
+
+  const region: GeofenceRegion = {
+    identifier: "user-gym",
+    latitude: params.latitude,
+    longitude: params.longitude,
+    radius: params.radiusMeters ?? DEFAULT_RADIUS_METERS,
+    notifyOnEnter: true,
+    notifyOnExit: true,
+  };
+
+  if (started) {
+    try {
+      await Location.stopGeofencingAsync(AUTO_WORKOUT_GEOFENCE_TASK);
+    } catch (error) {
+      if (!isTaskNotFoundError(error)) {
+        throw error;
+      }
+
+      log.warn("Geofence task was not found while stopping before restart", {
+        task: AUTO_WORKOUT_GEOFENCE_TASK,
+      });
+    }
+  }
+
+  await Location.startGeofencingAsync(AUTO_WORKOUT_GEOFENCE_TASK, [region]);
+}
+
+export async function disableAutoWorkoutGeofence(): Promise<void> {
+  try {
+    const started = await Location.hasStartedGeofencingAsync(
+      AUTO_WORKOUT_GEOFENCE_TASK,
+    );
+
+    if (!started) {
+      return;
+    }
+
+    await Location.stopGeofencingAsync(AUTO_WORKOUT_GEOFENCE_TASK);
+  } catch (error) {
+    if (!isTaskNotFoundError(error)) {
+      throw error;
+    }
+
+    log.warn("Geofence task was not found while disabling", {
+      task: AUTO_WORKOUT_GEOFENCE_TASK,
+    });
+  }
+}
+
+export async function syncAutoWorkoutGeofenceWithToken(
+  token: string,
+  options?: { requestPermissions?: boolean },
+): Promise<void> {
+  const shouldRequestPermissions = options?.requestPermissions ?? false;
+
+  await saveBackgroundAuthToken(token);
+
+  const foregroundPermission = await Location.getForegroundPermissionsAsync();
+  const foregroundStatus =
+    foregroundPermission.status === "granted"
+      ? foregroundPermission.status
+      : shouldRequestPermissions
+        ? (await Location.requestForegroundPermissionsAsync()).status
+        : foregroundPermission.status;
+
+  if (foregroundStatus !== "granted") {
+    log.info("Auto workout geofence disabled: foreground location not granted");
+    await disableAutoWorkoutGeofence();
+    return;
+  }
+
+  const backgroundPermission = await Location.getBackgroundPermissionsAsync();
+  const backgroundStatus =
+    backgroundPermission.status === "granted"
+      ? backgroundPermission.status
+      : shouldRequestPermissions
+        ? (await Location.requestBackgroundPermissionsAsync()).status
+        : backgroundPermission.status;
+
+  if (backgroundStatus !== "granted") {
+    log.info("Auto workout geofence disabled: background location not granted");
+    await disableAutoWorkoutGeofence();
+    return;
+  }
+
+  const currentGym = await userGymApi.getCurrentGym(token);
+  const gym = currentGym.gym;
+
+  if (
+    !gym ||
+    gym.geofenceEnabled === false ||
+    gym.latitude === null ||
+    gym.longitude === null
+  ) {
+    log.info("Auto workout geofence disabled: missing/disabled gym geofence");
+    await disableAutoWorkoutGeofence();
+    return;
+  }
+
+  await configureAutoWorkoutGeofence({
+    latitude: gym.latitude,
+    longitude: gym.longitude,
+    radiusMeters: gym.geofenceRadiusMeters ?? DEFAULT_RADIUS_METERS,
+  });
+}
+
+function isApiError(
+  error: unknown,
+  status: number,
+  expectedMessage: string,
+): boolean {
+  if (!error || typeof error !== "object") {
+    return false;
+  }
+
+  const maybe = error as {
+    response?: {
+      status?: number;
+      data?: unknown;
+    };
+  };
+
+  if (maybe.response?.status !== status) {
+    return false;
+  }
+
+  const data = maybe.response.data;
+  if (typeof data === "string") {
+    return data === expectedMessage;
+  }
+
+  if (data && typeof data === "object") {
+    const errorField = (data as { error?: unknown }).error;
+    if (typeof errorField === "string") {
+      return errorField.includes(expectedMessage);
+    }
+  }
+
+  return false;
+}
+
+function isTaskNotFoundError(error: unknown): boolean {
+  if (!error || typeof error !== "object") {
+    return false;
+  }
+
+  const message =
+    "message" in error && typeof error.message === "string"
+      ? error.message
+      : String(error);
+
+  return (
+    message.includes("TaskNotFoundException") || message.includes("not found")
+  );
+}