feat(mobile): add iOS/Android mobile app with SSO login, camera upload, and push notifications

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

mobile/src/hooks/usePushNotifications.ts

@@ -0,0 +1,114 @@
+/**
+ * usePushNotifications – register the device for push notifications.
+ *
+ * Requests the user's permission for notifications, obtains an Expo push
+ * token, and registers it with the DocuElevate backend via
+ * POST /api/mobile/register-device.
+ *
+ * This hook should be called once from the root component after the user has
+ * successfully authenticated.
+ */
+
+import Constants from "expo-constants";
+import * as Device from "expo-device";
+import * as Notifications from "expo-notifications";
+import { useCallback, useEffect, useRef } from "react";
+import { Platform } from "react-native";
+import api from "../services/api";
+
+Notifications.setNotificationHandler({
+  handleNotification: async () => ({
+    shouldShowAlert: true,
+    shouldPlaySound: true,
+    shouldSetBadge: true,
+  }),
+});
+
+export function usePushNotifications(isAuthenticated: boolean) {
+  const notificationListener = useRef<Notifications.Subscription | null>(null);
+  const responseListener = useRef<Notifications.Subscription | null>(null);
+
+  const registerForPushNotifications = useCallback(async () => {
+    if (!Device.isDevice) {
+      // Push tokens are not available in simulators.
+      return;
+    }
+
+    if (Platform.OS === "android") {
+      await Notifications.setNotificationChannelAsync("default", {
+        name: "DocuElevate",
+        importance: Notifications.AndroidImportance.MAX,
+        vibrationPattern: [0, 250, 250, 250],
+        lightColor: "#1e40af",
+      });
+    }
+
+    const { status: existingStatus } = await Notifications.getPermissionsAsync();
+    let finalStatus = existingStatus;
+
+    if (existingStatus !== "granted") {
+      const { status } = await Notifications.requestPermissionsAsync();
+      finalStatus = status;
+    }
+
+    if (finalStatus !== "granted") {
+      // User declined – no push notifications
+      return;
+    }
+
+    let projectId: string | undefined;
+    try {
+      projectId =
+        Constants.expoConfig?.extra?.eas?.projectId ??
+        Constants.easConfig?.projectId;
+    } catch {
+      // ignore
+    }
+
+    const tokenData = await Notifications.getExpoPushTokenAsync(
+      projectId ? { projectId } : undefined
+    );
+
+    const pushToken = tokenData.data;
+    const platform = Platform.OS as "ios" | "android" | "web";
+
+    let deviceName = "Mobile App";
+    try {
+      deviceName = Device.modelName ?? Device.deviceName ?? "Mobile App";
+    } catch {
+      // ignore
+    }
+
+    try {
+      await api.registerDevice({ push_token: pushToken, device_name: deviceName, platform });
+    } catch {
+      // Registration failure is non-fatal – the app still works without push.
+    }
+  }, []);
+
+  useEffect(() => {
+    if (!isAuthenticated) return;
+
+    registerForPushNotifications();
+
+    // Listen for incoming notifications while app is foregrounded
+    notificationListener.current = Notifications.addNotificationReceivedListener((notification) => {
+      console.log("Notification received:", notification.request.content.title);
+    });
+
+    // Listen for user taps on notifications
+    responseListener.current = Notifications.addNotificationResponseReceivedListener((response) => {
+      const data = response.notification.request.content.data as Record<string, unknown>;
+      // Navigate to file detail if file_id is present
+      if (data?.file_id) {
+        console.log("User tapped notification for file:", data.file_id);
+        // Navigation would be wired up by the caller via a callback prop
+      }
+    });
+
+    return () => {
+      notificationListener.current?.remove();
+      responseListener.current?.remove();
+    };
+  }, [isAuthenticated, registerForPushNotifications]);
+}