feat(platform,auth,app): align identity to companionglp.com and harden OAuth deep-link handoff

Identity: rename the application identity to com.companionglp.glpcompanion on every platform (Android applicationId/namespace + MainActivity package, iOS/macOS bundle IDs incl. RunnerTests, Windows CompanyName/copyright, web manifest id, Supabase OAuth redirect scheme).

Deep links: register the custom scheme com.companionglp.glpcompanion:// in iOS/macOS Info.plist (CFBundleURLTypes), the Android VIEW/BROWSABLE intent-filter, and Windows per-user HKCU protocol registration. Server-side steps (Supabase uri_allow-list, Entra optional email claim) are recorded in BUILD_STATE.md.

Windows runner: single-instance mutex (Local\GLPCompanionSingleInstance) so login callbacks are delivered deterministically; SendAppLinkToInstance forwarding with foreground/taskbar-flash fallback so protocol activation can never look like a hang; protocol diagnostics appended to TEMP glpcompanion-protocol.log.

macOS: add the missing com.apple.security.network.client entitlement so the sandboxed runner can reach Supabase at all.

Auth UX: surface deferred OAuth/magic-link handshake failures as snackbars on the login screen; make isAuthenticatedProvider reactive (watches authStateProvider) with a microtask-deferred router refresh so live sign-in and sign-out redirect correctly; add a debug package:logging listener so supabase_flutter diagnostics are visible under flutter run.

Field-verified on Windows: Google, Microsoft (Entra ID), and email magic-link sign-in round trips plus sign-out redirect to /login.

BUILD_STATE.md

@@ -111,4 +111,27 @@
 - [x] `dart run build_runner build --delete-conflicting-outputs` (44 outputs written)
 - [x] `flutter analyze --fatal-infos` (Zero issues — `No issues found!`)
 - [x] `flutter test` (123/123 passing)
-- [x] `flutter build web --no-tree-shake-icons` (conditional import keeps `package:health`/`dart:io` out of the web bundle)
+- [x] `flutter build web --no-tree-shake-icons` (conditional import keeps `package:health`/`dart:io` out of the web bundle)
+
+## Post-Phase-7 Additions
+- [x] Deep-link (OAuth / magic-link callback) registration across platforms (2026-10-17): the custom scheme `com.companionglp.glpcompanion` (mirrors the bundle identifiers behind `kAuthCallbackRedirectUrl`) is now registered in every OS routing table —
+  - iOS: `Runner/Info.plist` `CFBundleURLTypes` (`CFBundleTypeRole=Editor`, scheme `com.companionglp.glpcompanion`).
+  - macOS: `Runner/Info.plist` `CFBundleURLTypes` (same shape).
+  - Android: `VIEW`/`DEFAULT`/`BROWSABLE` intent-filter with `android:scheme="com.companionglp.glpcompanion"` on `.MainActivity` (existing `singleTop` launch mode routes `onNewIntent` to the running activity consumed by `app_links`).
+  - Windows runner: `RegisterAppLinkProtocol()` (windows/runner/utils.cpp) writes the per-user protocol under `HKCU\Software\Classes\com.companionglp.glpcompanion` (`URL Protocol` + `shell\open\command` → `"<exe>" "%1"`, no elevation, re-registered every launch); `wWinMain` calls `SendAppLinkToInstance()` (exported by the `app_links` Windows DLL) before creating a window so a protocol activation while the app is running forwards the URI to the existing instance over `WM_COPYDATA` instead of spawning a second window. Cold-start links continue to be read from the command line by the plugin.
+- [x] macOS entitlements fix (pre-existing gap, required for the OAuth round trip): `com.apple.security.network.client` added to `DebugProfile.entitlements` and `Release.entitlements` — the sandboxed macOS runner previously had no outbound-network entitlement, so Supabase (including the auth exchange the deep link feeds) was unreachable.
+- [x] `lib/features/auth/data/supabase_auth_service.dart` doc comment updated to reflect the actual registration points.
+- [x] Windows OAuth handoff diagnostics + no-hang guarantees (2026-10-17, after field report: chooser appears then "nothing happens"):
+  - Runner logs every protocol-activation step to `%TEMP%\glpcompanion-protocol.log` (and `OutputDebugString`): launch argv, `SendAppLinkToInstance()` outcome, and — in the original instance — every `WM_COPYDATA` receipt with `dwData`/payload (expected `dwData=1026` = `WM_USER+2`, the app_links tag).
+  - Fallback path hardened: when forwarding fails (e.g. UIPI drops `WM_COPYDATA` to an elevated target, or no instance found) the fresh instance now shows + foregrounds its window (taskbar flash fallback) and completes the code exchange itself via the plugin's pending-link path — protocol activation can no longer look like a hang.
+  - Dart: `package:logging` root listener (kDebugMode) added in `lib/main.dart` so supabase_flutter's auth/deeplink diagnostics (`handle deeplink uri`, `Error while getSessionFromUrl`) are visible under `flutter run`; `logging: ^1.3.0` promoted to a direct dependency in `pubspec.yaml`.
+- [x] Deferred auth-error surfacing (2026-10-17, after Microsoft-provider field failure looked like a "hang"): OAuth/magic-link handshake failures arrive *late* — the browser returns an `?error=...` callback, GoTrue's `notifyException` emits them as stream errors on `onAuthStateChange`, and nothing rendered them. `LoginScreen` now also listens to `authStateProvider` errors (router guard is unaffected — it reads `isAuthenticatedProvider`/live session directly, only bumping its refresh counter) and `_messageFor` translates the known "Error getting user email from external provider" failure into actionable guidance. Field-verified via the protocol log: the Windows WM_COPYDATA handoff (`dwData=1026` forwarded to the running instance) is confirmed working end-to-end.
+- [x] Microsoft (Entra ID) provider handshake fixed (2026-10-17): the `server_error` / "Error getting user email from external provider" bounced back to the app was resolved by adding the optional `email` ID claim to the Entra app registration (`b8852225-23a1-46ef-a28e-365d8ef1cb3f`) in the Azure portal (Token configuration → Optional claims). Field-verified: the next Microsoft round trip returned a clean `?code=8432da29-...` callback (protocol log, 14:40:59) delivered to the running instance through the app_links handoff.
+- [x] Single-instance enforcement (2026-10-17): Supabase Auth server logs (`POST /token` grant_type=pkce → 200 at 18:40:59Z, `user_signedup` for `mtkell@kellengineering.com`) proved the Microsoft exchange completed — in the *wrong window*. Two instances were running (protocol log: launches at 14:16 AND 14:37); the PKCE verifier lives in shared secure storage under one fixed key, so the callback was forwarded (Z-order) to the non-initiating instance, which silently completed the exchange server-side while the user's window stayed on the login screen. Fix: `AcquireSingleInstanceMutex()` (`Local\GLPCompanionSingleInstance`) in the Windows runner — duplicate normal launches activate the existing window and exit; protocol activations still forward to the sole window. Callback delivery is now deterministic.
+- [x] Reactive auth-guard state (2026-10-17): `isAuthenticatedProvider` read the non-reactive `currentSession` getter inside a plain `Provider`, caching its first-read value forever (nobody invalidated it). Booting already-signed-in cached `true`, so sign-out cleared the session (Identity card → "Not signed in", button disabled) but the guard kept passing — no redirect to `/login`; live sign-in navigation was equally broken but masked because every successful entry had been a boot-time session. Fixed by `ref.watch(authStateProvider)` inside the provider so the boolean is re-derived on every GoTrue transition; test overrides (`overrideWithValue`) bypass the body and are unaffected. Hardened further: the router's `refreshListenable` bump is deferred via `Future.microtask` so the redirect guard can never re-read `isAuthenticatedProvider` inside Riverpod's provider-notification cascade (ordering edge where a stale cached value could be observed); field log confirmed the `signedOut` event and local session removal fire correctly, isolating the issue to navigation only.
+- [x] End-to-end auth field verification (2026-10-17, user-confirmed): all three passwordless modes exercised live on Windows — Google OAuth, Microsoft (Entra ID) OAuth, and email magic link — each completing the custom-scheme round trip (`com.companionglp.glpcompanion://login-callback/`) through the single-instance `WM_COPYDATA` handoff into a persisted session; sign-out now redirects to `/login` and re-authentication re-enters the app without a relaunch.
+
+## Deep-Link Verification Gates (2026-10-17)
+- [x] Windows runner handoff — FIELD-PROVEN via `%TEMP%\glpcompanion-protocol.log`: protocol registration → OS chooser → second process launches with the link in argv → `WM_COPYDATA` (dwData=1026, the app_links tag) delivered to the running instance → clean forwarder exit. Observed on both the Google and Microsoft success round trips, plus the earlier `?error=` path (now surfaced on-screen by the login screen). No runner build gate remains — the running binary is the gate.
+- [ ] `flutter build apk --debug` / `flutter build ios --no-codesign` / `flutter build macos` — manifests/plists parse and build cleanly (needs a machine with the mobile toolchains; also exercises the iOS/macOS `CFBundleURLTypes` and Android intent-filter additions).
+- [x] Supabase Auth redirect allow-list configured (2026-10-17, via Supabase Management API on project `pyrgjdvqbjzakuwvbpxw` "glp-companion"): `uri_allow_list` now = `io.supabase.glpcompanion://login-callback,http://localhost:3000/**,com.companionglp.glpcompanion://login-callback,com.companionglp.glpcompanion://**` (previous entries preserved; stale `io.supabase.*` scheme kept for rollback). Post-write GET verified no collateral changes. `site_url` intentionally left at `http://localhost:8080` — update to `https://companionglp.com` once the web deployment is live.

android/app/build.gradle.kts

@@ -5,7 +5,7 @@ plugins {
 }
 
 android {
-    namespace = "com.glpcompanion.glpcompanion"
+    namespace = "com.companionglp.glpcompanion"
     compileSdk = flutter.compileSdkVersion
     ndkVersion = flutter.ndkVersion
 
@@ -20,7 +20,7 @@ android {
 
     defaultConfig {
         // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
-        applicationId = "com.glpcompanion.glpcompanion"
+        applicationId = "com.companionglp.glpcompanion"
         // You can update the following values to match your application needs.
         // For more information, see: https://flutter.dev/to/review-gradle-config.
         //

android/app/src/main/AndroidManifest.xml

@@ -37,6 +37,15 @@
                 <action android:name="android.intent.action.MAIN"/>
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
+            <!-- OAuth / magic-link return: custom scheme mirroring the
+                 applicationId so the OS routes Supabase auth redirects back
+                 into the running activity (app_links / supabase_flutter). -->
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW"/>
+                <category android:name="android.intent.category.DEFAULT"/>
+                <category android:name="android.intent.category.BROWSABLE"/>
+                <data android:scheme="com.companionglp.glpcompanion"/>
+            </intent-filter>
         </activity>
         <!-- Don't delete the meta-data below.
              This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->

android/app/src/main/kotlin/com/companionglp/glpcompanion/MainActivity.kt

@@ -1,4 +1,4 @@
-package com.glpcompanion.glpcompanion
+package com.companionglp.glpcompanion
 
 import io.flutter.embedding.android.FlutterActivity
 

ios/Runner.xcodeproj/project.pbxproj

@@ -383,7 +383,7 @@
 					"$(inherited)",
 					"@executable_path/Frameworks",
 				);
-				PRODUCT_BUNDLE_IDENTIFIER = com.glpcompanion.glpcompanion;
+				PRODUCT_BUNDLE_IDENTIFIER = com.companionglp.glpcompanion;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OBJC_BRIDGING_HEADER = "Runner/Runner-Bridging-Header.h";
 				SWIFT_VERSION = 5.0;
@@ -399,7 +399,7 @@
 				CURRENT_PROJECT_VERSION = 1;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
-				PRODUCT_BUNDLE_IDENTIFIER = com.glpcompanion.glpcompanion.RunnerTests;
+				PRODUCT_BUNDLE_IDENTIFIER = com.companionglp.glpcompanion.RunnerTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_ACTIVE_COMPILATION_CONDITIONS = DEBUG;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
@@ -416,7 +416,7 @@
 				CURRENT_PROJECT_VERSION = 1;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
-				PRODUCT_BUNDLE_IDENTIFIER = com.glpcompanion.glpcompanion.RunnerTests;
+				PRODUCT_BUNDLE_IDENTIFIER = com.companionglp.glpcompanion.RunnerTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_VERSION = 5.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/Runner.app/$(BUNDLE_EXECUTABLE_FOLDER_PATH)/Runner";
@@ -431,7 +431,7 @@
 				CURRENT_PROJECT_VERSION = 1;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
-				PRODUCT_BUNDLE_IDENTIFIER = com.glpcompanion.glpcompanion.RunnerTests;
+				PRODUCT_BUNDLE_IDENTIFIER = com.companionglp.glpcompanion.RunnerTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_VERSION = 5.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/Runner.app/$(BUNDLE_EXECUTABLE_FOLDER_PATH)/Runner";
@@ -564,7 +564,7 @@
 					"$(inherited)",
 					"@executable_path/Frameworks",
 				);
-				PRODUCT_BUNDLE_IDENTIFIER = com.glpcompanion.glpcompanion;
+				PRODUCT_BUNDLE_IDENTIFIER = com.companionglp.glpcompanion;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OBJC_BRIDGING_HEADER = "Runner/Runner-Bridging-Header.h";
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
@@ -586,7 +586,7 @@
 					"$(inherited)",
 					"@executable_path/Frameworks",
 				);
-				PRODUCT_BUNDLE_IDENTIFIER = com.glpcompanion.glpcompanion;
+				PRODUCT_BUNDLE_IDENTIFIER = com.companionglp.glpcompanion;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OBJC_BRIDGING_HEADER = "Runner/Runner-Bridging-Header.h";
 				SWIFT_VERSION = 5.0;

ios/Runner/Info.plist

@@ -22,6 +22,19 @@
 	<string>$(FLUTTER_BUILD_NAME)</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
+	<key>CFBundleURLTypes</key>
+	<array>
+		<dict>
+			<key>CFBundleTypeRole</key>
+			<string>Editor</string>
+			<key>CFBundleURLName</key>
+			<string>com.companionglp.glpcompanion</string>
+			<key>CFBundleURLSchemes</key>
+			<array>
+				<string>com.companionglp.glpcompanion</string>
+			</array>
+		</dict>
+	</array>
 	<key>CFBundleVersion</key>
 	<string>$(FLUTTER_BUILD_NUMBER)</string>
 	<key>NSHealthShareUsageDescription</key>

lib/app/router/app_router.dart

@@ -25,12 +25,21 @@ final _shellNavigatorKey = GlobalKey<NavigatorState>();
 /// Whether the current session satisfies the authenticated guard.
 ///
 /// Reads the live GoTrue session when the SDK is initialized and reports
-/// `false` otherwise. Extracted into a provider so integration tests can
+/// `false` otherwise. Watches [authStateProvider] so the value is re-derived
-/// simulate an authenticated (or unauthenticated) session without booting
+/// on every GoTrue transition — `currentSession` itself is a plain, non
-/// Supabase — they simply override this value.
+/// reactive getter, so without the watch this provider would cache whatever
+/// was true at first read (e.g. booting already signed-in) and a later
+/// sign-out could never redirect to `/login`. Extracted into a provider so
+/// integration tests can simulate an authenticated (or unauthenticated)
+/// session without booting Supabase — they simply override this value.
 final isAuthenticatedProvider = Provider<bool>(
-  (ref) => isSupabaseAvailable &&
+  (ref) {
-      Supabase.instance.client.auth.currentSession != null,
+    // Recompute on every auth transition (signedIn / signedOut /
+    // tokenRefreshed / initialSession).
+    ref.watch(authStateProvider);
+    return isSupabaseAvailable &&
+        Supabase.instance.client.auth.currentSession != null;
+  },
 );
 
 /// Application router with a reactive authentication guard and dev bypass hook.
@@ -38,8 +47,18 @@ final routerProvider = Provider<GoRouter>((ref) {
   final authRefreshNotifier = ValueNotifier<int>(0);
   ref.onDispose(authRefreshNotifier.dispose);
 
-  // Trigger re-evaluation on GoTrue auth transitions or dev bypass toggle
+  // Trigger re-evaluation on GoTrue auth transitions or dev bypass toggle.
-  ref.listen(authStateProvider, (_, __) => authRefreshNotifier.value++);
+  //
+  // The auth bump is deferred by one microtask so Riverpod finishes
+  // propagating the transition to dependent providers (notably
+  // isAuthenticatedProvider, which watches authStateProvider) before the
+  // redirect guard re-reads them; ValueNotifier listeners otherwise run
+  // inside the provider-notification cascade and could observe a stale
+  // cached value (symptom: sign-out clears the session but never navigates
+  // to /login).
+  ref.listen(authStateProvider, (_, __) {
+    Future.microtask(() => authRefreshNotifier.value++);
+  });
   ref.listen(devAuthBypassProvider, (_, __) => authRefreshNotifier.value++);
 
   return GoRouter(

lib/features/auth/data/supabase_auth_service.dart

@@ -7,13 +7,15 @@ import '../domain/auth_service.dart';
 /// or magic-link round trip on native platforms.
 ///
 /// The scheme mirrors the platform bundle identifiers
-/// (`com.glpcompanion.glpcompanion`) and must be registered in the iOS/macOS
+/// (`com.companionglp.glpcompanion`) and is registered in the iOS/macOS
-/// `Info.plist`, the Android manifest intent filters, and the Windows runner
+/// `Info.plist` (`CFBundleURLTypes`), the Android manifest intent filters,
-/// so the operating system can route the redirect callback back to the app.
+/// and the Windows runner (per-user protocol registration + single-instance
+/// forwarding) so the operating system can route the redirect callback back
+/// to the app.
 /// [SupabaseAuth] (bundled with `supabase_flutter`) observes the deep link and
 /// exchanges the returned auth code for a session automatically.
 const kAuthCallbackRedirectUrl =
-    'com.glpcompanion.glpcompanion://login-callback/';
+    'com.companionglp.glpcompanion://login-callback/';
 
 /// Resolves the redirect URL embedded in OAuth and magic-link flows.
 ///

lib/features/auth/presentation/screens/login_screen.dart

@@ -46,6 +46,17 @@ class _LoginScreenState extends ConsumerState<LoginScreen> {
       _showSnack(_messageFor(error), isError: true);
     });
 
+    // Deferred failures from a completed OAuth / magic-link round trip: when
+    // the browser returns an ?error=... callback (e.g. a provider handshake
+    // failure), Supabase Auth surfaces it as a stream error on
+    // onAuthStateChange long after the launch button returned. Without this
+    // listener the failure is silent and the screen appears to hang.
+    ref.listen(authStateProvider, (previous, next) {
+      final error = next.error;
+      if (error == null) return;
+      _showSnack(_messageFor(error), isError: true);
+    });
+
     final isBusy = ref.watch(authControllerProvider).isLoading;
 
     return Scaffold(
@@ -247,7 +258,20 @@ class _LoginScreenState extends ConsumerState<LoginScreen> {
   }
 
   String _messageFor(Object error) {
-    if (error is AuthException) return error.message;
+    if (error is AuthException) {
+      // Server-side handshake failures arrive late (via the deep-link
+      // callback) with raw upstream text; translate the known ones into
+      // actionable guidance.
+      if (error.message.contains('Error getting user email')) {
+        return 'Sign-in failed: the provider did not return an email '
+            'address for this account. This usually means the provider is '
+            'missing its email claim (e.g. the optional "email" claim in a '
+            'Microsoft Entra app registration). Try another sign-in method.';
+      }
+      if (error.message.isNotEmpty) {
+        return 'Sign-in failed: ${error.message}';
+      }
+    }
     return 'Authentication failed. Please try again.';
   }
 

lib/main.dart

@@ -4,12 +4,27 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_dotenv/flutter_dotenv.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:logging/logging.dart';
 import 'package:supabase_flutter/supabase_flutter.dart';
 import 'app/router/app_router.dart';
 
 Future<void> main() async {
   WidgetsFlutterBinding.ensureInitialized();
 
+  // Surface package:logging records (notably supabase_flutter's auth and
+  // deep-link diagnostics, e.g. "handle deeplink uri" or exchange errors
+  // that are otherwise silently swallowed) to the debug console so OAuth
+  // handoff issues are observable under `flutter run`.
+  if (kDebugMode) {
+    Logger.root.level = Level.ALL;
+    Logger.root.onRecord.listen((record) {
+      final suffix =
+          record.error != null ? ' | error: ${record.error}' : '';
+      debugPrint('[${record.loggerName}] ${record.level.name}: '
+          '${record.message}$suffix');
+    });
+  }
+
   // Load environment variables from .env
   await dotenv.load(fileName: '.env');
 

macos/Runner.xcodeproj/project.pbxproj

@@ -395,7 +395,7 @@
 				CURRENT_PROJECT_VERSION = 1;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
-				PRODUCT_BUNDLE_IDENTIFIER = com.glpcompanion.glpcompanion.RunnerTests;
+				PRODUCT_BUNDLE_IDENTIFIER = com.companionglp.glpcompanion.RunnerTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_VERSION = 5.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/glpcompanion.app/$(BUNDLE_EXECUTABLE_FOLDER_PATH)/glpcompanion";
@@ -409,7 +409,7 @@
 				CURRENT_PROJECT_VERSION = 1;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
-				PRODUCT_BUNDLE_IDENTIFIER = com.glpcompanion.glpcompanion.RunnerTests;
+				PRODUCT_BUNDLE_IDENTIFIER = com.companionglp.glpcompanion.RunnerTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_VERSION = 5.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/glpcompanion.app/$(BUNDLE_EXECUTABLE_FOLDER_PATH)/glpcompanion";
@@ -423,7 +423,7 @@
 				CURRENT_PROJECT_VERSION = 1;
 				GENERATE_INFOPLIST_FILE = YES;
 				MARKETING_VERSION = 1.0;
-				PRODUCT_BUNDLE_IDENTIFIER = com.glpcompanion.glpcompanion.RunnerTests;
+				PRODUCT_BUNDLE_IDENTIFIER = com.companionglp.glpcompanion.RunnerTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_VERSION = 5.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/glpcompanion.app/$(BUNDLE_EXECUTABLE_FOLDER_PATH)/glpcompanion";

macos/Runner/Configs/AppInfo.xcconfig

@@ -8,7 +8,7 @@
 PRODUCT_NAME = glpcompanion
 
 // The application's bundle identifier
-PRODUCT_BUNDLE_IDENTIFIER = com.glpcompanion.glpcompanion
+PRODUCT_BUNDLE_IDENTIFIER = com.companionglp.glpcompanion
 
 // The copyright displayed in application information
-PRODUCT_COPYRIGHT = Copyright © 2026 com.glpcompanion. All rights reserved.
+PRODUCT_COPYRIGHT = Copyright © 2026 com.companionglp. All rights reserved.

macos/Runner/DebugProfile.entitlements

@@ -6,6 +6,8 @@
 	<true/>
 	<key>com.apple.security.cs.allow-jit</key>
 	<true/>
+	<key>com.apple.security.network.client</key>
+	<true/>
 	<key>com.apple.security.network.server</key>
 	<true/>
 </dict>

macos/Runner/Info.plist

@@ -18,6 +18,19 @@
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
 	<string>$(FLUTTER_BUILD_NAME)</string>
+	<key>CFBundleURLTypes</key>
+	<array>
+		<dict>
+			<key>CFBundleTypeRole</key>
+			<string>Editor</string>
+			<key>CFBundleURLName</key>
+			<string>com.companionglp.glpcompanion</string>
+			<key>CFBundleURLSchemes</key>
+			<array>
+				<string>com.companionglp.glpcompanion</string>
+			</array>
+		</dict>
+	</array>
 	<key>CFBundleVersion</key>
 	<string>$(FLUTTER_BUILD_NUMBER)</string>
 	<key>LSMinimumSystemVersion</key>

macos/Runner/Release.entitlements

@@ -4,5 +4,7 @@
 <dict>
 	<key>com.apple.security.app-sandbox</key>
 	<true/>
+	<key>com.apple.security.network.client</key>
+	<true/>
 </dict>
 </plist>

pubspec.lock

@@ -606,7 +606,7 @@ packages:
     source: hosted
     version: "3.0.0"
   logging:
-    dependency: transitive
+    dependency: "direct main"
     description:
       name: logging
       sha256: c8245ada5f1717ed44271ed1c26b8ce85ca3228fd2ffdb75468ab01979309d61

pubspec.yaml

@@ -39,6 +39,7 @@ dependencies:
   flutter_local_notifications: ^17.1.0
 
   flutter_dotenv: ^5.1.0
+  logging: ^1.3.0
   supabase_flutter: ^2.5.0
   path: ^1.9.1
   path_provider: ^2.1.6

web/manifest.json

@@ -1,6 +1,7 @@
 {
     "name": "GLP-1 Companion",
     "short_name": "GLP Companion",
+    "id": "/",
     "start_url": ".",
     "display": "standalone",
     "background_color": "#D4E4C7",

windows/runner/Runner.rc

@@ -89,11 +89,11 @@ BEGIN
     BEGIN
         BLOCK "040904e4"
         BEGIN
-            VALUE "CompanyName", "com.glpcompanion" "\0"
+            VALUE "CompanyName", "com.companionglp" "\0"
             VALUE "FileDescription", "glpcompanion" "\0"
             VALUE "FileVersion", VERSION_AS_STRING "\0"
             VALUE "InternalName", "glpcompanion" "\0"
-            VALUE "LegalCopyright", "Copyright (C) 2026 com.glpcompanion. All rights reserved." "\0"
+            VALUE "LegalCopyright", "Copyright (C) 2026 com.companionglp. All rights reserved." "\0"
             VALUE "OriginalFilename", "glpcompanion.exe" "\0"
             VALUE "ProductName", "glpcompanion" "\0"
             VALUE "ProductVersion", VERSION_AS_STRING "\0"

windows/runner/flutter_window.cpp

@@ -1,8 +1,11 @@
 #include "flutter_window.h"
 
+#include <cstring>
 #include <optional>
+#include <string>
 
 #include "flutter/generated_plugin_registrant.h"
+#include "utils.h"
 
 FlutterWindow::FlutterWindow(const flutter::DartProject& project)
     : project_(project) {}
@@ -51,6 +54,24 @@ LRESULT
 FlutterWindow::MessageHandler(HWND hwnd, UINT const message,
                               WPARAM const wparam,
                               LPARAM const lparam) noexcept {
+  // OAuth handoff diagnostics: the app_links plugin consumes WM_COPYDATA
+  // tagged with its own dwData (WM_USER + 2 == 1026). Log every WM_COPYDATA
+  // so the protocol log shows whether a link reached this instance.
+  if (message == WM_COPYDATA) {
+    const auto* cds = reinterpret_cast<const COPYDATASTRUCT*>(lparam);
+    std::string detail = "WM_COPYDATA received";
+    if (cds != nullptr) {
+      detail += "; dwData=" + std::to_string(cds->dwData);
+      detail += " bytes=" + std::to_string(cds->cbData);
+      if (cds->lpData != nullptr && cds->cbData > 0) {
+        const char* payload = static_cast<const char*>(cds->lpData);
+        detail += " payload=";
+        detail.append(payload, strnlen(payload, cds->cbData));
+      }
+    }
+    LogAppLink(detail);
+  }
+
   // Give Flutter, including plugins, an opportunity to handle window messages.
   if (flutter_controller_) {
     std::optional<LRESULT> result =

windows/runner/main.cpp

@@ -2,11 +2,61 @@
 #include <flutter/flutter_view_controller.h>
 #include <windows.h>
 
+#include "app_links/app_links_plugin_c_api.h"
 #include "flutter_window.h"
 #include "utils.h"
 
 int APIENTRY wWinMain(_In_ HINSTANCE instance, _In_opt_ HINSTANCE prev,
                       _In_ wchar_t *command_line, _In_ int show_command) {
+  // Diagnostic breadcrumb: protocol activations carry the link as the only
+  // command-line argument; regular launches have none.
+  int argc = 0;
+  wchar_t** argv = ::CommandLineToArgvW(::GetCommandLineW(), &argc);
+  if (argv != nullptr) {
+    std::string cmdline;
+    for (int i = 0; i < argc; ++i) {
+      cmdline += Utf8FromUtf16(argv[i]);
+      cmdline += ' ';
+    }
+    ::LocalFree(argv);
+    LogAppLink("launched with: " + cmdline);
+  }
+
+  const bool protocol_launch = HasAppLinkArgument();
+  const bool is_primary = AcquireSingleInstanceMutex();
+
+  // (Re)register the per-user custom scheme so OAuth / magic-link redirects
+  // launched by the browser can activate this app.
+  RegisterAppLinkProtocol();
+
+  // Exactly one instance may own a window: the PKCE code verifier lives in
+  // shared secure storage, so a login callback delivered to a window other
+  // than the one that initiated the sign-in would silently complete the
+  // exchange in the WRONG window while the user keeps staring at a login
+  // screen. Duplicate normal launches surface the existing instance and
+  // exit instead of starting a competing window.
+  if (!protocol_launch && !is_primary) {
+    ::SendAppLinkToInstance();  // best-effort: surface the existing window
+    LogAppLink("another instance owns the app; exiting");
+    return EXIT_SUCCESS;
+  }
+
+  // Protocol activation while an instance is already running hands the link
+  // to that instance (over WM_COPYDATA, consumed by the app_links plugin)
+  // and exits, instead of spawning a second window.
+  if (::SendAppLinkToInstance()) {
+    LogAppLink("link forwarded to the running instance; exiting");
+    return EXIT_SUCCESS;
+  }
+
+  if (protocol_launch) {
+    LogAppLink(is_primary
+                   ? "cold start with link; handling it directly in this "
+                     "process"
+                   : "forwarding failed; handling the link in this secondary "
+                     "process");
+  }
+
   // Attach to console when present (e.g., 'flutter run') or create a
   // new console when running with a debugger.
   if (!::AttachConsole(ATTACH_PARENT_PROCESS) && ::IsDebuggerPresent()) {
@@ -32,6 +82,20 @@ int APIENTRY wWinMain(_In_ HINSTANCE instance, _In_opt_ HINSTANCE prev,
   }
   window.SetQuitOnClose(true);
 
+  if (protocol_launch) {
+    // Windows protocol activation must not look like a hang: surface the
+    // window that will complete the exchange (Windows blocks background
+    // processes from stealing focus, so fall back to a taskbar flash).
+    HWND hwnd = window.GetHandle();
+    if (hwnd != nullptr) {
+      ::ShowWindow(hwnd, SW_SHOW);
+      if (!::SetForegroundWindow(hwnd)) {
+        FLASHWINFO flash = {sizeof(FLASHWINFO), hwnd, FLASHW_ALL, 5, 0};
+        ::FlashWindowEx(&flash);
+      }
+    }
+  }
+
   ::MSG msg;
   while (::GetMessage(&msg, nullptr, 0, 0)) {
     ::TranslateMessage(&msg);

windows/runner/utils.cpp

@@ -67,3 +67,117 @@ std::string Utf8FromUtf16(const wchar_t* utf16_string) {
   }
   return utf8_string;
 }
+
+namespace {
+// Must match kAuthCallbackRedirectUrl in
+// lib/features/auth/data/supabase_auth_service.dart.
+constexpr wchar_t kAppLinkProtocol[] = L"com.companionglp.glpcompanion";
+}  // namespace
+
+void RegisterAppLinkProtocol() {
+  wchar_t exe_path[MAX_PATH];
+  const DWORD length = ::GetModuleFileNameW(nullptr, exe_path, MAX_PATH);
+  if (length == 0 || length >= MAX_PATH) {
+    return;
+  }
+
+  const std::wstring exe(exe_path, length);
+  // "%1" receives the activated link, e.g.
+  // com.companionglp.glpcompanion://login-callback/?code=...
+  const std::wstring command = L"\"" + exe + L"\" \"%1\"";
+
+  const std::wstring protocol_key =
+      std::wstring(L"Software\\Classes\\") + kAppLinkProtocol;
+
+  HKEY key = nullptr;
+  if (::RegCreateKeyExW(HKEY_CURRENT_USER, protocol_key.c_str(), 0, nullptr,
+                        REG_OPTION_NON_VOLATILE, KEY_WRITE, nullptr, &key,
+                        nullptr) == ERROR_SUCCESS) {
+    const std::wstring description = L"URL:GLP-1 Companion Protocol";
+    ::RegSetValueExW(
+        key, nullptr, 0, REG_SZ,
+        reinterpret_cast<const BYTE*>(description.c_str()),
+        static_cast<DWORD>((description.size() + 1) * sizeof(wchar_t)));
+    const std::wstring url_protocol = L"";
+    ::RegSetValueExW(
+        key, L"URL Protocol", 0, REG_SZ,
+        reinterpret_cast<const BYTE*>(url_protocol.c_str()),
+        static_cast<DWORD>((url_protocol.size() + 1) * sizeof(wchar_t)));
+    ::RegCloseKey(key);
+  }
+
+  const std::wstring command_key = protocol_key + L"\\shell\\open\\command";
+  if (::RegCreateKeyExW(HKEY_CURRENT_USER, command_key.c_str(), 0, nullptr,
+                        REG_OPTION_NON_VOLATILE, KEY_WRITE, nullptr, &key,
+                        nullptr) == ERROR_SUCCESS) {
+    ::RegSetValueExW(
+        key, nullptr, 0, REG_SZ,
+        reinterpret_cast<const BYTE*>(command.c_str()),
+        static_cast<DWORD>((command.size() + 1) * sizeof(wchar_t)));
+    ::RegCloseKey(key);
+  }
+}
+
+void LogAppLink(const std::string& message) {
+  wchar_t temp[MAX_PATH];
+  const DWORD temp_length = ::GetTempPathW(MAX_PATH, temp);
+  if (temp_length == 0 || temp_length >= MAX_PATH) {
+    return;
+  }
+  const std::wstring path =
+      std::wstring(temp, temp_length) + L"glpcompanion-protocol.log";
+
+  SYSTEMTIME stamp_source = {};
+  ::GetLocalTime(&stamp_source);
+  char stamp[32] = {};
+  snprintf(stamp, sizeof(stamp), "[%02u:%02u:%02u.%03u] ",
+           stamp_source.wHour, stamp_source.wMinute, stamp_source.wSecond,
+           stamp_source.wMilliseconds);
+
+  FILE* log_file = nullptr;
+  if (_wfopen_s(&log_file, path.c_str(), L"a") == 0 && log_file != nullptr) {
+    fprintf(log_file, "%s%s\n", stamp, message.c_str());
+    fclose(log_file);
+  }
+  ::OutputDebugStringA((std::string(stamp) + message + "\n").c_str());
+}
+
+bool HasAppLinkArgument() {
+  int argc = 0;
+  wchar_t** argv = ::CommandLineToArgvW(::GetCommandLineW(), &argc);
+  if (argv == nullptr) {
+    return false;
+  }
+  // Mirrors applinks::AppLinksPlugin::GetLink(): exactly one extra argument
+  // carrying a URI scheme counts as a protocol activation.
+  bool has_link = false;
+  if (argc == 2) {
+    const std::wstring arg(argv[1]);
+    has_link = arg.find(L"://") != std::wstring::npos;
+  }
+  ::LocalFree(argv);
+  return has_link;
+}
+
+namespace {
+// Held for the process lifetime once claimed; the OS releases it on exit.
+HANDLE g_single_instance_mutex = nullptr;
+}  // namespace
+
+bool AcquireSingleInstanceMutex() {
+  if (g_single_instance_mutex != nullptr) {
+    return true;
+  }
+  g_single_instance_mutex =
+      ::CreateMutexW(nullptr, TRUE, L"Local\\GLPCompanionSingleInstance");
+  if (g_single_instance_mutex == nullptr) {
+    // Fail open: never block launch on a mutex problem.
+    return true;
+  }
+  if (::GetLastError() == ERROR_ALREADY_EXISTS) {
+    ::CloseHandle(g_single_instance_mutex);
+    g_single_instance_mutex = nullptr;
+    return false;
+  }
+  return true;
+}

windows/runner/utils.h

@@ -16,4 +16,23 @@ std::string Utf8FromUtf16(const wchar_t* utf16_string);
 // encoded in UTF-8. Returns an empty std::vector<std::string> on failure.
 std::vector<std::string> GetCommandLineArguments();
 
+// Registers the per-user URL protocol (HKCU\Software\Classes) for OAuth /
+// magic-link callbacks so Windows routes com.companionglp.glpcompanion://
+// links to this executable. Idempotent and requires no elevation.
+void RegisterAppLinkProtocol();
+
+// Appends a timestamped line to %TEMP%\glpcompanion-protocol.log and the
+// debugger output stream. Used to diagnose the OAuth custom-scheme handoff.
+void LogAppLink(const std::string& message);
+
+// True when this process was started by Windows protocol activation, i.e.
+// its command line carries a single URI argument such as
+// com.companionglp.glpcompanion://login-callback/?code=...
+bool HasAppLinkArgument();
+
+// Claims the per-session single-instance mutex for this process. Returns
+// false when a previous instance already owns it (callers should then
+// activate that instance and exit instead of starting a competing window).
+bool AcquireSingleInstanceMutex();
+
 #endif  // RUNNER_UTILS_H_