fix: merge main, address code review feedback for security fix PR #816

- Merge origin/main into branch (resolve conflict in integrations_dashboard.html)
- Add defensive JSON parsing with try/except for integration.config
- Wrap tester() call in try/except to prevent 500 errors from bad config
- Add i18n key integrations.connection_test_failed_fallback in en.json
- Reference i18n key in template JS fallback message
- Update SECURITY_AUDIT.md: add fix date (2026-03-23), update doc date
- Remove accidental revert.sh file
- Fix missing MagicMock/patch imports in test file
- Add tests for invalid JSON config and tester exception error paths

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>
Agent-Logs-Url: https://github.com/christianlouis/DocuElevate/sessions/daebb70e-059a-4601-8864-88eef49f99cf

mobile/app/_layout.tsx

@@ -4,23 +4,135 @@
  * Wraps the entire app in AuthProvider and SafeAreaProvider, then uses the
  * AuthGuard component to redirect between the unauthenticated (auth) route
  * group and the authenticated (tabs) route group based on session state.
+ *
+ * ShareProvider + Linking listener: when iOS opens the app via the share
+ * sheet (CFBundleDocumentTypes) or Android via a SEND intent, the incoming
+ * file:// / content:// URL is captured and forwarded to UploadScreen via
+ * ShareContext.
+ *
+ * The companion `+not-found.tsx` handles the case where expo-router receives
+ * a `docuelevate://` URL with a filesystem path (from iOS "Open In…") and
+ * cannot match it to a route.  It adds the file directly to ShareContext and
+ * redirects to the Upload tab so the file is uploaded transparently.
  */
 
+import * as Linking from "expo-linking";
 import { Stack, useRouter, useSegments } from "expo-router";
 import React, { useEffect } from "react";
 import { ActivityIndicator, StyleSheet, Text, View } from "react-native";
 import { SafeAreaProvider } from "react-native-safe-area-context";
 import { AuthProvider, useAuth } from "../src/context/AuthContext";
+import { ShareProvider, useShare } from "../src/context/ShareContext";
+import { LocaleProvider, useLocale, isLanguageSupported } from "../src/i18n";
+import { mimeTypeFromFilename } from "../src/utils/mimeTypes";
+
+// ---------------------------------------------------------------------------
+// Helpers
+// ---------------------------------------------------------------------------
+
+/** The custom URL scheme registered in app.json. */
+const APP_SCHEME_PREFIX = "docuelevate://";
+
+/**
+ * Known deep-link path prefixes that should NOT be treated as shared files.
+ * These are in-app deep-link routes handled by their respective screens
+ * (e.g. QR login, OAuth callback).
+ */
+const DEEP_LINK_PATHS = ["qr-login", "callback"];
+
+/** Extract a display filename from a file:// or content:// URI. */
+function filenameFromUri(uri: string): string {
+  try {
+    const decoded = decodeURIComponent(uri);
+    // Take the last path segment and strip any query string
+    const last = decoded.split("/").pop() ?? "shared_file";
+    return last.split("?")[0] || "shared_file";
+  } catch {
+    return "shared_file";
+  }
+}
+
+/**
+ * Build a Linking URL handler that forwards incoming file:// / content://
+ * URLs to ShareContext.  Extracted as a module-level factory so the handler
+ * itself is created once and can be easily unit-tested without a React context.
+ *
+ * On iOS the Share Sheet / "Open In…" action may deliver the file path under
+ * the app's custom URL scheme (`docuelevate://…/file.pdf`) instead of a plain
+ * `file://` URL.  When that happens we rewrite the URL to `file:///…` so the
+ * upload logic can read the file normally.
+ *
+ * Note: expo-router also receives the same URL and will attempt to match it as
+ * an in-app route.  When no route matches it renders `+not-found.tsx`, which
+ * adds the file to ShareContext directly and redirects to the Upload tab.
+ * Both this handler and `+not-found.tsx` call `addPendingFile`;
+ * `ShareContext` deduplicates by URI so the file is only uploaded once.
+ */
+function makeUrlHandler(addPendingFile: (f: { uri: string; filename: string; mimeType?: string }) => void) {
+  return ({ url }: { url: string }) => {
+    let fileUri = url;
+
+    // iOS may pass a filesystem path under the app's custom scheme.
+    // Rewrite it to a file:// URL unless it looks like an in-app deep-link
+    // (expo-router groups always start with "(").
+    if (url.startsWith(APP_SCHEME_PREFIX)) {
+      const path = url.slice(APP_SCHEME_PREFIX.length);
+
+      // Skip known in-app deep-link paths (e.g. qr-login, callback).
+      // These are handled by their respective screens, not the share flow.
+      const pathBase = path.split("?")[0].replace(/^\/+/, "");
+      if (DEEP_LINK_PATHS.includes(pathBase) || path.startsWith("(")) {
+        return;
+      }
+
+      if (path.length > 0) {
+        fileUri = "file:///" + path.replace(/^\/+/, "");
+      }
+    }
+
+    if (!fileUri.startsWith("file://") && !fileUri.startsWith("content://")) return;
+    const filename = filenameFromUri(fileUri);
+    addPendingFile({ uri: fileUri, filename, mimeType: mimeTypeFromFilename(filename) });
+  };
+}
 
 // ---------------------------------------------------------------------------
 // Auth guard – redirects to the correct route group after auth state resolves
 // ---------------------------------------------------------------------------
 
 function AuthGuard() {
-  const { isLoading, isAuthenticated } = useAuth();
+  const { isLoading, isAuthenticated, user } = useAuth();
+  const { addPendingFile } = useShare();
+  const { setLang } = useLocale();
   const segments = useSegments();
   const router = useRouter();
 
+  // Apply the server-side language preference whenever the user profile is
+  // loaded (on login or app resume).  This syncs the language set on the
+  // desktop/web client to the mobile app.  If the server language is not
+  // supported by the mobile app, we leave the current language unchanged.
+  useEffect(() => {
+    if (user?.preferred_language && isLanguageSupported(user.preferred_language)) {
+      void setLang(user.preferred_language);
+    }
+  }, [user?.preferred_language, setLang]);
+
+  // Listen for files shared from other apps (iOS Share Sheet / Android Intent).
+  // Both cold-start (app was not running) and warm-start (app in background)
+  // cases are handled.
+  useEffect(() => {
+    const handleIncomingUrl = makeUrlHandler(addPendingFile);
+
+    // Cold start – app launched directly by a share action
+    Linking.getInitialURL().then((url) => {
+      if (url) handleIncomingUrl({ url });
+    });
+
+    // Warm start – app was already running when the share action occurred
+    const subscription = Linking.addEventListener("url", handleIncomingUrl);
+    return () => subscription.remove();
+  }, [addPendingFile]);
+
   useEffect(() => {
     if (isLoading) return;
 
@@ -46,8 +158,11 @@ function AuthGuard() {
 
   return (
     <Stack screenOptions={{ headerShown: false }}>
+      <Stack.Screen name="index" />
       <Stack.Screen name="(auth)" />
       <Stack.Screen name="(tabs)" />
+      {/* +not-found handles unmatched routes such as iOS "Open In…" file paths */}
+      <Stack.Screen name="+not-found" />
     </Stack>
   );
 }
@@ -59,9 +174,13 @@ function AuthGuard() {
 export default function RootLayout() {
   return (
     <SafeAreaProvider>
-      <AuthProvider>
-        <AuthGuard />
-      </AuthProvider>
+      <LocaleProvider>
+        <ShareProvider>
+          <AuthProvider>
+            <AuthGuard />
+          </AuthProvider>
+        </ShareProvider>
+      </LocaleProvider>
     </SafeAreaProvider>
   );
 }