no chart

lib/screens/attempt_screen.dart

@@ -477,6 +477,8 @@ class _AttemptScreenState extends State<AttemptScreen> {
     // Add attempt to history
     final historyEntry = AttemptHistoryEntry.fromAttemptResult(
       result: result.result,
+      totalQuestionsInDeck: result.updatedDeck.numberOfQuestions,
+      knownCount: result.updatedDeck.knownCount,
       timestamp: endTime,
     );
     final updatedDeckWithHistory = result.updatedDeck.copyWith(

lib/screens/deck_list_screen.dart

@@ -193,7 +193,7 @@ class _DeckListScreenState extends State<DeckListScreen> {
   void _useDefaultDeck() async {
     // Check if default deck already exists
     final baseDeck = DefaultDeck.deck;
-    final deckExists = _deckStorage.hasDeckSync(baseDeck.id);
+    final deckExists = await _deckStorage.hasDeck(baseDeck.id);
     
     // Show dialog to ask if user wants mock data (only if deck doesn't exist)
     bool? includeMockData = false;
@@ -214,36 +214,47 @@ class _DeckListScreenState extends State<DeckListScreen> {
         ? DefaultDeck.deckWithMockData 
         : DefaultDeck.deck;
     
-    if (deckExists) {
-      // If it exists, create a copy with a new ID
-      final clonedDeck = defaultDeck.copyWith(
-        id: '${defaultDeck.id}_${DateTime.now().millisecondsSinceEpoch}',
-      );
-      _deckStorage.saveDeckSync(clonedDeck);
-      
-      if (mounted) {
-        ScaffoldMessenger.of(context).showSnackBar(
-          const SnackBar(
-            content: Text('Default deck added successfully'),
-            backgroundColor: Colors.green,
-          ),
+    try {
+      if (deckExists) {
+        // If it exists, create a copy with a new ID
+        final clonedDeck = defaultDeck.copyWith(
+          id: '${defaultDeck.id}_${DateTime.now().millisecondsSinceEpoch}',
         );
+        await _deckStorage.saveDeck(clonedDeck);
+        
+        if (mounted) {
+          ScaffoldMessenger.of(context).showSnackBar(
+            const SnackBar(
+              content: Text('Default deck added successfully'),
+              backgroundColor: Colors.green,
+            ),
+          );
+        }
+      } else {
+        // Save default deck to storage
+        await _deckStorage.saveDeck(defaultDeck);
+        
+        if (mounted) {
+          ScaffoldMessenger.of(context).showSnackBar(
+            const SnackBar(
+              content: Text('Default deck added successfully'),
+              backgroundColor: Colors.green,
+            ),
+          );
+        }
       }
-    } else {
-      // Save default deck to storage
-      _deckStorage.saveDeckSync(defaultDeck);
       
+      _loadDecks();
+    } catch (e) {
       if (mounted) {
         ScaffoldMessenger.of(context).showSnackBar(
-          const SnackBar(
-            content: Text('Default deck added successfully'),
-            backgroundColor: Colors.green,
+          SnackBar(
+            content: Text('Error adding deck: $e'),
+            backgroundColor: Colors.red,
           ),
         );
       }
     }
-    
-    _loadDecks();
   }
 
   @override

lib/screens/deck_overview_screen.dart

@@ -2,7 +2,6 @@ import 'package:flutter/material.dart';
 import 'package:practice_engine/practice_engine.dart';
 import '../routes.dart';
 import '../services/deck_storage.dart';
-import '../widgets/attempts_chart.dart';
 
 class DeckOverviewScreen extends StatefulWidget {
   const DeckOverviewScreen({super.key});
@@ -283,6 +282,105 @@ class _DeckOverviewScreenState extends State<DeckOverviewScreen> {
     }
   }
 
+  Widget _buildProgressStats(BuildContext context) {
+    if (_deck == null) return const SizedBox.shrink();
+    
+    final totalQuestions = _deck!.numberOfQuestions;
+    final knownCount = _deck!.knownCount;
+    final unknownCount = totalQuestions - knownCount;
+    final unknownPercentage = totalQuestions > 0 
+        ? (unknownCount / totalQuestions * 100.0) 
+        : 0.0;
+    final knownPercentage = totalQuestions > 0 
+        ? (knownCount / totalQuestions * 100.0) 
+        : 0.0;
+    
+    // Get progress trend if we have history
+    // Attempt history is stored chronologically (oldest first), so first is oldest, last is newest
+    String? trendText;
+    if (_deck!.attemptHistory.isNotEmpty) {
+      final oldestAttempt = _deck!.attemptHistory.first;
+      final newestAttempt = _deck!.attemptHistory.last;
+      final oldestUnknown = oldestAttempt.unknownPercentage;
+      final newestUnknown = newestAttempt.unknownPercentage;
+      final improvement = oldestUnknown - newestUnknown;
+      
+      if (improvement > 0) {
+        trendText = 'Improved by ${improvement.toStringAsFixed(1)}% since first attempt';
+      } else if (improvement < 0) {
+        trendText = '${improvement.abs().toStringAsFixed(1)}% more to learn since first attempt';
+      } else {
+        trendText = 'No change since first attempt';
+      }
+    }
+    
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        // Main stat: Unknown percentage
+        Row(
+          mainAxisAlignment: MainAxisAlignment.spaceBetween,
+          children: [
+            Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  'Questions to Learn',
+                  style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                        color: Theme.of(context).colorScheme.onSurface.withValues(alpha: 0.7),
+                      ),
+                ),
+                const SizedBox(height: 4),
+                Text(
+                  '${unknownPercentage.toStringAsFixed(1)}%',
+                  style: Theme.of(context).textTheme.headlineMedium?.copyWith(
+                        fontWeight: FontWeight.bold,
+                        color: Theme.of(context).colorScheme.primary,
+                      ),
+                ),
+                Text(
+                  '$unknownCount of $totalQuestions questions',
+                  style: Theme.of(context).textTheme.bodySmall,
+                ),
+              ],
+            ),
+            Column(
+              crossAxisAlignment: CrossAxisAlignment.end,
+              children: [
+                Text(
+                  'Questions Known',
+                  style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                        color: Theme.of(context).colorScheme.onSurface.withValues(alpha: 0.7),
+                      ),
+                ),
+                const SizedBox(height: 4),
+                Text(
+                  '${knownPercentage.toStringAsFixed(1)}%',
+                  style: Theme.of(context).textTheme.headlineMedium?.copyWith(
+                        fontWeight: FontWeight.bold,
+                        color: Theme.of(context).colorScheme.secondary,
+                      ),
+                ),
+                Text(
+                  '$knownCount of $totalQuestions questions',
+                  style: Theme.of(context).textTheme.bodySmall,
+                ),
+              ],
+            ),
+          ],
+        ),
+        if (trendText != null) ...[
+          const SizedBox(height: 12),
+          Text(
+            trendText,
+            style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                  color: Theme.of(context).colorScheme.onSurface.withValues(alpha: 0.6),
+                ),
+          ),
+        ],
+      ],
+    );
+  }
 
   @override
   Widget build(BuildContext context) {
@@ -462,15 +560,12 @@ class _DeckOverviewScreenState extends State<DeckOverviewScreen> {
                       const Divider(),
                       const SizedBox(height: 8),
                       Text(
-                        'Progress Chart',
+                        'Learning Progress',
                         style: Theme.of(context).textTheme.titleSmall,
                       ),
-                      const SizedBox(height: 8),
-                      // Progress chart
-                      AttemptsChart(
-                        attempts: _deck!.attemptHistory,
-                        maxDisplayItems: 15,
-                      ),
+                      const SizedBox(height: 12),
+                      // Current progress
+                      _buildProgressStats(context),
                     ],
                   ],
                 ),