TF-4145 Use generateWebLink for paywall url

core/lib/utils/web_link_generator.dart

@@ -2,16 +2,14 @@ import 'package:core/core.dart';
 
 /// Utility class for generating web links in flat subdomain format.
 class WebLinkGenerator {
-  const WebLinkGenerator();
-
   /// Ensures that a path starts with `/`.
-  String ensureFirstSlash(String? path) {
+  static String ensureFirstSlash(String? path) {
     if (path == null || path.isEmpty) return '/';
     return path.startsWith('/') ? path : '/$path';
   }
 
   /// Validates if a given FQDN looks valid (has at least 2 parts and non-empty).
-  bool isValidFqdn(String fqdn) {
+  static bool isValidFqdn(String fqdn) {
     if (fqdn.trim().isEmpty || !fqdn.contains('.')) return false;
     final parts = fqdn.split('.').where((p) => p.trim().isNotEmpty).toList();
     return parts.length >= 2;
@@ -20,9 +18,9 @@ class WebLinkGenerator {
   /// Generates a web link based on a workplace FQDN and app slug.
   ///
   /// Throws [ArgumentError] when input is invalid.
-  String generateWebLink({
+  static String generateWebLink({
     required String workplaceFqdn,
-    required String slug,
+    String? slug,
     String? pathname,
     String? hash,
     List<List<String>>? searchParams,
@@ -31,16 +29,22 @@ class WebLinkGenerator {
       throw ArgumentError('Invalid workplace FQDN: $workplaceFqdn');
     }
 
-    final hostParts = workplaceFqdn
+    // Start from the base host
-        .split('.')
+    String newHost = workplaceFqdn;
-        .where((p) => p.trim().isNotEmpty)
-        .toList();
 
-    hostParts[0] = '${hostParts[0]}-$slug';
+    // Only modify the host when slug is non-null and not empty
-    final newHost = hostParts.join('.');
+    if (slug != null && slug.trim().isNotEmpty) {
+      final hostParts =
+          workplaceFqdn.split('.').where((p) => p.trim().isNotEmpty).toList();
+
+      // Insert slug as a prefix to the first part (flat subdomain)
+      hostParts[0] = '${hostParts[0]}-$slug';
+      newHost = hostParts.join('.');
+    }
 
     final safePath = ensureFirstSlash(pathname);
-    final safeHash = (hash == null || hash.isEmpty) ? null : ensureFirstSlash(hash);
+    final safeHash =
+        (hash == null || hash.isEmpty) ? null : ensureFirstSlash(hash);
 
     final queryParams = <String, String>{};
     for (final param in searchParams ?? const []) {
@@ -61,16 +65,14 @@ class WebLinkGenerator {
   /// A safe version of [generateWebLink] that **never throws**.
   ///
   /// Returns `''` (empty string) when an error occurs.
-  String safeGenerateWebLink({
+  static String safeGenerateWebLink({
     required String workplaceFqdn,
-    required String slug,
+    String? slug,
     String? pathname,
     String? hash,
     List<List<String>>? searchParams,
   }) {
     try {
-      if (slug.trim().isEmpty) return '';
-
       return generateWebLink(
         workplaceFqdn: workplaceFqdn,
         slug: slug,

core/test/utils/web_link_generator_test.dart

@@ -2,11 +2,9 @@ import 'package:core/utils/web_link_generator.dart';
 import 'package:flutter_test/flutter_test.dart';
 
 void main() {
-  group('WebLinkGenerator (with workplaceFqdn)', () {
+  group('WebLinkGenerator', () {
-    const generator = WebLinkGenerator();
-
     test('should generate correct link for flat subdomain', () {
-      final result = generator.generateWebLink(
+      final result = WebLinkGenerator.generateWebLink(
         workplaceFqdn: 'alice.example.app',
         searchParams: [
           ['sharecode', 'sharingIsCaring'],
@@ -24,7 +22,7 @@ void main() {
     });
 
     test('should prepend slash to path and hash if missing', () {
-      final result = generator.generateWebLink(
+      final result = WebLinkGenerator.generateWebLink(
         workplaceFqdn: 'bob.example.tools',
         pathname: 'files',
         hash: 'folder/123',
@@ -35,7 +33,7 @@ void main() {
     });
 
     test('should work with no search params', () {
-      final result = generator.generateWebLink(
+      final result = WebLinkGenerator.generateWebLink(
         workplaceFqdn: 'charlie.domain.com',
         slug: 'settings',
       );
@@ -43,9 +41,9 @@ void main() {
       expect(result, 'https://charlie-settings.domain.com/');
     });
 
-    test('should throw when workplaceFqdn is empty', () {
+    test('✅ should throw when workplaceFqdn is empty', () {
       expect(
-        () => generator.generateWebLink(
+        () => WebLinkGenerator.generateWebLink(
           workplaceFqdn: '',
           slug: 'notes',
         ),
@@ -55,7 +53,7 @@ void main() {
 
     test('should throw when workplaceFqdn only contains TLD', () {
       expect(
-        () => generator.generateWebLink(
+        () => WebLinkGenerator.generateWebLink(
           workplaceFqdn: 'com',
           slug: 'notes',
         ),
@@ -65,7 +63,7 @@ void main() {
 
     test('should throw when workplaceFqdn has no dot', () {
       expect(
-        () => generator.generateWebLink(
+        () => WebLinkGenerator.generateWebLink(
           workplaceFqdn: 'localhost',
           slug: 'notes',
         ),
@@ -74,7 +72,7 @@ void main() {
     });
 
     test('should handle malformed FQDN gracefully (multiple dots)', () {
-      final result = generator.generateWebLink(
+      final result = WebLinkGenerator.generateWebLink(
         workplaceFqdn: '....example..app',
         slug: 'notes',
       );
@@ -84,7 +82,7 @@ void main() {
     });
 
     test('should ignore malformed searchParams', () {
-      final result = generator.generateWebLink(
+      final result = WebLinkGenerator.generateWebLink(
         workplaceFqdn: 'dave.example.app',
         slug: 'drive',
         searchParams: [
@@ -97,7 +95,7 @@ void main() {
     });
 
     test('should not add fragment when hash is empty string', () {
-      final result = generator.generateWebLink(
+      final result = WebLinkGenerator.generateWebLink(
         workplaceFqdn: 'eve.example.app',
         slug: 'settings',
         hash: '',
@@ -106,8 +104,35 @@ void main() {
       expect(result, 'https://eve-settings.example.app/');
     });
 
+    test('should keep original host when slug is null', () {
+      final result = WebLinkGenerator.generateWebLink(
+        workplaceFqdn: 'alice.example.app',
+        slug: null,
+      );
+
+      expect(result, 'https://alice.example.app/');
+    });
+
+    test('should keep original host when slug is empty', () {
+      final result = WebLinkGenerator.generateWebLink(
+        workplaceFqdn: 'alice.example.app',
+        slug: '',
+      );
+
+      expect(result, 'https://alice.example.app/');
+    });
+
+    test('should keep original host when slug is only whitespace', () {
+      final result = WebLinkGenerator.generateWebLink(
+        workplaceFqdn: 'bob.example.app',
+        slug: '   ',
+      );
+
+      expect(result, 'https://bob.example.app/');
+    });
+
     test('safeGenerateWebLink should return empty string on invalid FQDN', () {
-      final result = generator.safeGenerateWebLink(
+      final result = WebLinkGenerator.safeGenerateWebLink(
         workplaceFqdn: '',
         slug: 'notes',
       );
@@ -115,22 +140,31 @@ void main() {
       expect(result, '');
     });
 
-    test('safeGenerateWebLink should return empty string on missing slug', () {
+    test('safeGenerateWebLink should return valid URL on missing slug', () {
-      final result = generator.safeGenerateWebLink(
+      final result = WebLinkGenerator.safeGenerateWebLink(
         workplaceFqdn: 'alice.example.app',
         slug: '',
       );
 
-      expect(result, '');
+      expect(result, 'https://alice.example.app/');
     });
 
     test('safeGenerateWebLink should still return valid URL when input ok', () {
-      final result = generator.safeGenerateWebLink(
+      final result = WebLinkGenerator.safeGenerateWebLink(
         workplaceFqdn: 'bob.example.app',
         slug: 'drive',
       );
 
       expect(result, 'https://bob-drive.example.app/');
     });
+
+    test('safeGenerateWebLink should handle slug = null gracefully', () {
+      final result = WebLinkGenerator.safeGenerateWebLink(
+        workplaceFqdn: 'example.com',
+        slug: null,
+      );
+
+      expect(result, 'https://example.com/');
+    });
   });
 }

lib/features/paywall/presentation/paywall_controller.dart

@@ -1,6 +1,8 @@
 import 'package:core/presentation/extensions/color_extension.dart';
 import 'package:core/presentation/state/failure.dart';
 import 'package:core/presentation/state/success.dart';
+import 'package:core/utils/app_logger.dart';
+import 'package:core/utils/web_link_generator.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_svg/flutter_svg.dart';
 import 'package:tmail_ui_user/features/base/base_controller.dart';
@@ -39,10 +41,7 @@ class PaywallController extends BaseController {
     paywallUrlPattern = newPattern;
     if (isRetryGetPaywallUrl) {
       isRetryGetPaywallUrl = false;
-      final qualifiedPaywall = paywallUrlPattern!.getQualifiedUrl(
+      final qualifiedPaywall = getPaywallUrl(paywallUrlPattern!);
-        ownerEmail: ownEmailAddress,
-        domainName: RouteUtils.getRootDomain(),
-      );
       AppUtils.launchLink(qualifiedPaywall);
     }
   }
@@ -88,13 +87,33 @@ class PaywallController extends BaseController {
       _showMessagePaywallUrlNotAvailable(context: context);
       return;
     }
+    final qualifiedPaywall = getPaywallUrl(paywallUrlPattern!);
+    AppUtils.launchLink(qualifiedPaywall);
+  }
 
-    final qualifiedPaywall = paywallUrlPattern!.getQualifiedUrl(
+  String getPaywallUrl(PaywallUrlPattern pattern) {
+    final defaultUrl = pattern.getQualifiedUrl(
       ownerEmail: ownEmailAddress,
       domainName: RouteUtils.getRootDomain(),
     );
 
-    AppUtils.launchLink(qualifiedPaywall);
+    try {
+      final workplaceFqdn = twakeAppManager.oidcUserInfo?.workplaceFqdn?.trim();
+      if (workplaceFqdn == null || workplaceFqdn.isEmpty) {
+        return defaultUrl;
+      }
+
+      final paywallUrl = WebLinkGenerator.safeGenerateWebLink(
+        workplaceFqdn: workplaceFqdn,
+        pathname: 'paywall',
+      );
+
+      // Fallback if generated URL is empty or invalid
+      return paywallUrl.isNotEmpty ? paywallUrl : defaultUrl;
+    } catch (e) {
+      logError('$runtimeType::getPaywallUrl: Failed to generate paywall URL: $e');
+      return defaultUrl;
+    }
   }
 
   void _handleRetryGetPaywallUrl() {