Add welcome popup, changelog system, and account deletion button

lib/screens/about_screen.dart

@@ -68,7 +68,18 @@ class AboutScreen extends StatelessWidget {
                 ),
                 textAlign: TextAlign.center,
               ),
-              const SizedBox(height: 32),
+              const SizedBox(height: 24),
+              // Release Notes button
+              Center(
+                child: OutlinedButton.icon(
+                  onPressed: () {
+                    Navigator.pushNamed(context, '/settings/release-notes');
+                  },
+                  icon: const Icon(Icons.article_outlined),
+                  label: const Text('View Release Notes'),
+                ),
+              ),
+              const SizedBox(height: 24),
               _buildHelpLinks(context),
             ],
           ),
@@ -93,10 +104,76 @@ class AboutScreen extends StatelessWidget {
         _buildLinkText(context, 'Contact', 'https://deflock.me/contact'),
         const SizedBox(height: 8),
         _buildLinkText(context, 'Donate', 'https://deflock.me/donate'),
+        const SizedBox(height: 24),
+        
+        // Divider for account management section
+        Divider(
+          color: Theme.of(context).dividerColor.withOpacity(0.3),
+        ),
+        const SizedBox(height: 16),
+        
+        // Account deletion link (less prominent)
+        _buildAccountDeletionLink(context),
       ],
     );
   }
 
+  Widget _buildAccountDeletionLink(BuildContext context) {
+    final locService = LocalizationService.instance;
+    
+    return GestureDetector(
+      onTap: () => _showDeleteAccountDialog(context, locService),
+      child: Text(
+        locService.t('auth.deleteAccount'),
+        style: Theme.of(context).textTheme.bodySmall?.copyWith(
+          color: Theme.of(context).colorScheme.error.withOpacity(0.7),
+          decoration: TextDecoration.underline,
+        ),
+        textAlign: TextAlign.center,
+      ),
+    );
+  }
+
+  void _showDeleteAccountDialog(BuildContext context, LocalizationService locService) {
+    showDialog(
+      context: context,
+      builder: (context) => AlertDialog(
+        title: Text(locService.t('auth.deleteAccount')),
+        content: Column(
+          mainAxisSize: MainAxisSize.min,
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Text(locService.t('auth.deleteAccountExplanation')),
+            const SizedBox(height: 12),
+            Text(
+              locService.t('auth.deleteAccountWarning'),
+              style: TextStyle(
+                fontWeight: FontWeight.bold,
+                color: Theme.of(context).colorScheme.error,
+              ),
+            ),
+          ],
+        ),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.of(context).pop(),
+            child: Text(locService.t('actions.cancel')),
+          ),
+          TextButton(
+            onPressed: () {
+              Navigator.of(context).pop();
+              _launchUrl('https://www.openstreetmap.org/account/deletion', context);
+            },
+            style: TextButton.styleFrom(
+              foregroundColor: Theme.of(context).colorScheme.error,
+            ),
+            child: Text(locService.t('auth.goToOSM')),
+          ),
+        ],
+      ),
+    );
+  }
+
   Widget _buildLinkText(BuildContext context, String text, String url) {
     return GestureDetector(
       onTap: () => _launchUrl(url, context),

lib/screens/home_screen.dart

@@ -19,9 +19,12 @@ import '../widgets/measured_sheet.dart';
 import '../widgets/navigation_sheet.dart';
 import '../widgets/search_bar.dart';
 import '../widgets/suspected_location_sheet.dart';
+import '../widgets/welcome_dialog.dart';
+import '../widgets/changelog_dialog.dart';
 import '../models/osm_node.dart';
 import '../models/suspected_location.dart';
 import '../models/search_result.dart';
+import '../services/changelog_service.dart';
 
 class HomeScreen extends StatefulWidget {
   const HomeScreen({super.key});
@@ -48,6 +51,9 @@ class _HomeScreenState extends State<HomeScreen> with TickerProviderStateMixin {
   
   // Track selected node for highlighting
   int? _selectedNodeId;
+  
+  // Track popup display to avoid showing multiple times
+  bool _hasCheckedForPopup = false;
 
   @override
   void initState() {
@@ -219,6 +225,52 @@ class _HomeScreenState extends State<HomeScreen> with TickerProviderStateMixin {
     });
   }
 
+  // Check for and display welcome/changelog popup
+  Future<void> _checkForPopup() async {
+    if (!mounted) return;
+    
+    try {
+      final popupType = await ChangelogService().getPopupType();
+      
+      if (!mounted) return; // Check again after async operation
+      
+      switch (popupType) {
+        case PopupType.welcome:
+          await showDialog(
+            context: context,
+            barrierDismissible: false,
+            builder: (context) => const WelcomeDialog(),
+          );
+          break;
+        
+        case PopupType.changelog:
+          final changelogContent = ChangelogService().getChangelogForCurrentVersion();
+          if (changelogContent != null) {
+            await showDialog(
+              context: context,
+              barrierDismissible: false,
+              builder: (context) => ChangelogDialog(changelogContent: changelogContent),
+            );
+          }
+          break;
+        
+        case PopupType.none:
+          // No popup needed, but still update version tracking for future launches
+          await ChangelogService().updateLastSeenVersion();
+          break;
+      }
+    } catch (e) {
+      // Silently handle errors to avoid breaking the app launch
+      debugPrint('[HomeScreen] Error checking for popup: $e');
+      // Still update version tracking in case of error
+      try {
+        await ChangelogService().updateLastSeenVersion();
+      } catch (e2) {
+        debugPrint('[HomeScreen] Error updating version: $e2');
+      }
+    }
+  }
+
   void _onStartRoute() {
     final appState = context.read<AppState>();
     
@@ -526,6 +578,12 @@ class _HomeScreenState extends State<HomeScreen> with TickerProviderStateMixin {
       }
     }
 
+    // Check for welcome/changelog popup after app is fully initialized
+    if (appState.isInitialized && !_hasCheckedForPopup) {
+      _hasCheckedForPopup = true;
+      WidgetsBinding.instance.addPostFrameCallback((_) => _checkForPopup());
+    }
+
     // Pass the active sheet height directly to the map
     final activeSheetHeight = _addSheetHeight > 0 
         ? _addSheetHeight 

lib/screens/release_notes_screen.dart

@@ -0,0 +1,191 @@
+import 'package:flutter/material.dart';
+import '../services/changelog_service.dart';
+import '../services/version_service.dart';
+
+class ReleaseNotesScreen extends StatefulWidget {
+  const ReleaseNotesScreen({super.key});
+
+  @override
+  State<ReleaseNotesScreen> createState() => _ReleaseNotesScreenState();
+}
+
+class _ReleaseNotesScreenState extends State<ReleaseNotesScreen> {
+  Map<String, String>? _changelogs;
+  bool _isLoading = true;
+
+  @override
+  void initState() {
+    super.initState();
+    _loadChangelogs();
+  }
+
+  Future<void> _loadChangelogs() async {
+    try {
+      // Ensure changelog service is initialized
+      if (!ChangelogService().isInitialized) {
+        await ChangelogService().init();
+      }
+      
+      final changelogs = ChangelogService().getAllChangelogs();
+      
+      if (mounted) {
+        setState(() {
+          _changelogs = changelogs;
+          _isLoading = false;
+        });
+      }
+    } catch (e) {
+      debugPrint('[ReleaseNotesScreen] Error loading changelogs: $e');
+      if (mounted) {
+        setState(() {
+          _changelogs = {};
+          _isLoading = false;
+        });
+      }
+    }
+  }
+
+  List<String> _sortVersions(List<String> versions) {
+    // Simple version sorting - splits by '.' and compares numerically
+    versions.sort((a, b) {
+      final aParts = a.split('.').map(int.tryParse).where((v) => v != null).cast<int>().toList();
+      final bParts = b.split('.').map(int.tryParse).where((v) => v != null).cast<int>().toList();
+      
+      // Compare version parts (reverse order for newest first)
+      for (int i = 0; i < aParts.length && i < bParts.length; i++) {
+        final comparison = bParts[i].compareTo(aParts[i]); // Reverse for desc order
+        if (comparison != 0) return comparison;
+      }
+      
+      // If one version has more parts, the longer one is newer
+      return bParts.length.compareTo(aParts.length);
+    });
+    
+    return versions;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Release Notes'),
+      ),
+      body: _isLoading
+          ? const Center(child: CircularProgressIndicator())
+          : _changelogs == null || _changelogs!.isEmpty
+              ? const Center(
+                  child: Padding(
+                    padding: EdgeInsets.all(24.0),
+                    child: Text(
+                      'No release notes available.',
+                      style: TextStyle(fontSize: 16),
+                      textAlign: TextAlign.center,
+                    ),
+                  ),
+                )
+              : ListView(
+                  padding: const EdgeInsets.all(16),
+                  children: [
+                    // Current version indicator
+                    Container(
+                      padding: const EdgeInsets.all(12),
+                      margin: const EdgeInsets.only(bottom: 16),
+                      decoration: BoxDecoration(
+                        color: Theme.of(context).colorScheme.primaryContainer,
+                        borderRadius: BorderRadius.circular(8),
+                        border: Border.all(
+                          color: Theme.of(context).colorScheme.primary.withOpacity(0.3),
+                        ),
+                      ),
+                      child: Row(
+                        children: [
+                          Icon(
+                            Icons.info_outline,
+                            color: Theme.of(context).colorScheme.primary,
+                          ),
+                          const SizedBox(width: 8),
+                          Text(
+                            'Current Version: ${VersionService().version}',
+                            style: TextStyle(
+                              fontWeight: FontWeight.bold,
+                              color: Theme.of(context).colorScheme.primary,
+                            ),
+                          ),
+                        ],
+                      ),
+                    ),
+                    
+                    // Changelog entries
+                    ..._buildChangelogEntries(),
+                  ],
+                ),
+    );
+  }
+
+  List<Widget> _buildChangelogEntries() {
+    if (_changelogs == null || _changelogs!.isEmpty) return [];
+
+    final sortedVersions = _sortVersions(_changelogs!.keys.toList());
+    final currentVersion = VersionService().version;
+
+    return sortedVersions.map((version) {
+      final content = _changelogs![version]!;
+      final isCurrentVersion = version == currentVersion;
+
+      return Container(
+        margin: const EdgeInsets.only(bottom: 16),
+        decoration: BoxDecoration(
+          border: Border.all(
+            color: isCurrentVersion
+                ? Theme.of(context).colorScheme.primary.withOpacity(0.3)
+                : Theme.of(context).dividerColor.withOpacity(0.3),
+          ),
+          borderRadius: BorderRadius.circular(8),
+        ),
+        child: ExpansionTile(
+          title: Row(
+            children: [
+              Text(
+                'Version $version',
+                style: TextStyle(
+                  fontWeight: FontWeight.bold,
+                  color: isCurrentVersion
+                      ? Theme.of(context).colorScheme.primary
+                      : null,
+                ),
+              ),
+              if (isCurrentVersion) ...[
+                const SizedBox(width: 8),
+                Container(
+                  padding: const EdgeInsets.symmetric(horizontal: 6, vertical: 2),
+                  decoration: BoxDecoration(
+                    color: Theme.of(context).colorScheme.primary,
+                    borderRadius: BorderRadius.circular(12),
+                  ),
+                  child: Text(
+                    'CURRENT',
+                    style: TextStyle(
+                      fontSize: 10,
+                      fontWeight: FontWeight.bold,
+                      color: Theme.of(context).colorScheme.onPrimary,
+                    ),
+                  ),
+                ),
+              ],
+            ],
+          ),
+          children: [
+            Container(
+              width: double.infinity,
+              padding: const EdgeInsets.all(16),
+              child: Text(
+                content,
+                style: const TextStyle(height: 1.4),
+              ),
+            ),
+          ],
+        ),
+      );
+    }).toList();
+  }
+}