Implement enhanced Analytics Dashboard with visualizations and detailed metrics

analytics-endpoint.js

@@ -0,0 +1,164 @@
+// Enhanced Analytics API endpoint for the Spelling Practice App
+
+// Get analytics data with additional metrics
+app.get('/getAnalytics', (req, res) => {
+  try {
+    const results = readJsonSafe(path.join(DATA_DIR, files.results), {});
+    
+    // Prepare analytics data structure
+    const analytics = {
+      summary: {
+        totalSessions: 0,
+        totalWords: 0,
+        correctWords: 0,
+        overallAccuracy: 0,
+        averageScore: 0,
+        mostMissedWords: [],
+        activityByDate: {}
+      },
+      userStats: {},
+      wordStats: {}
+    };
+    
+    // Process all results data
+    Object.keys(results).forEach(username => {
+      // Skip if user has no results
+      if (!Array.isArray(results[username]) || results[username].length === 0) return;
+      
+      // Initialize user stats if not already present
+      if (!analytics.userStats[username]) {
+        analytics.userStats[username] = {
+          totalSessions: 0,
+          totalWords: 0,
+          correctWords: 0,
+          accuracy: 0,
+          averageScore: 0,
+          trend: [], // For progress over time
+          recentResults: [],
+          problemWords: []
+        };
+      }
+      
+      // Process each session for this user
+      results[username].forEach(session => {
+        // Skip invalid sessions
+        if (!session || !session.answers || !Array.isArray(session.answers)) return;
+        
+        // Update summary counts
+        analytics.summary.totalSessions++;
+        analytics.userStats[username].totalSessions++;
+        
+        // Process session date for activity tracking
+        const sessionDate = new Date(session.timestamp || Date.now()).toISOString().split('T')[0];
+        analytics.summary.activityByDate[sessionDate] = (analytics.summary.activityByDate[sessionDate] || 0) + 1;
+        
+        // Collect score for trending data
+        if (typeof session.score === 'number' && session.answers.length > 0) {
+          const accuracy = session.score / session.answers.length;
+          analytics.userStats[username].trend.push({
+            date: sessionDate,
+            accuracy: accuracy * 100,
+            score: session.score,
+            total: session.answers.length
+          });
+        }
+        
+        // Keep only most recent 10 sessions for the trend data
+        if (analytics.userStats[username].trend.length > 10) {
+          analytics.userStats[username].trend = analytics.userStats[username].trend.slice(-10);
+        }
+        
+        // Get the 5 most recent results for display
+        if (analytics.userStats[username].recentResults.length < 5) {
+          analytics.userStats[username].recentResults.push({
+            date: new Date(session.timestamp || Date.now()).toLocaleString(),
+            score: session.score,
+            total: session.answers.length,
+            completed: session.completed
+          });
+        }
+        
+        // Process individual words in the session
+        session.answers.forEach(answer => {
+          // Skip invalid answers
+          if (!answer || typeof answer.word !== 'string') return;
+          
+          // Update word stats
+          const word = answer.word.toLowerCase();
+          
+          if (!analytics.wordStats[word]) {
+            analytics.wordStats[word] = {
+              attempts: 0,
+              correct: 0,
+              incorrect: 0,
+              accuracy: 0
+            };
+          }
+          
+          analytics.wordStats[word].attempts++;
+          analytics.summary.totalWords++;
+          analytics.userStats[username].totalWords++;
+          
+          if (answer.correct) {
+            analytics.wordStats[word].correct++;
+            analytics.summary.correctWords++;
+            analytics.userStats[username].correctWords++;
+          } else {
+            analytics.wordStats[word].incorrect++;
+            
+            // Track problem words for this user
+            const problemWordIndex = analytics.userStats[username].problemWords.findIndex(pw => pw.word === word);
+            
+            if (problemWordIndex >= 0) {
+              analytics.userStats[username].problemWords[problemWordIndex].count++;
+            } else {
+              analytics.userStats[username].problemWords.push({
+                word,
+                count: 1
+              });
+            }
+          }
+          
+          // Calculate accuracy for this word
+          analytics.wordStats[word].accuracy = 
+            analytics.wordStats[word].correct / analytics.wordStats[word].attempts * 100;
+        });
+        
+        // Calculate user accuracy and average score
+        analytics.userStats[username].accuracy = 
+          analytics.userStats[username].correctWords / analytics.userStats[username].totalWords * 100 || 0;
+        analytics.userStats[username].averageScore = 
+          analytics.userStats[username].correctWords / analytics.userStats[username].totalSessions || 0;
+      });
+      
+      // Sort problem words by count (descending)
+      analytics.userStats[username].problemWords.sort((a, b) => b.count - a.count);
+      
+      // Keep only top 5 problem words
+      analytics.userStats[username].problemWords = analytics.userStats[username].problemWords.slice(0, 5);
+    });
+    
+    // Calculate overall metrics
+    analytics.summary.overallAccuracy = 
+      analytics.summary.correctWords / analytics.summary.totalWords * 100 || 0;
+    analytics.summary.averageScore = 
+      analytics.summary.correctWords / analytics.summary.totalSessions || 0;
+    
+    // Find most missed words (top 5)
+    const missedWords = Object.keys(analytics.wordStats)
+      .map(word => ({
+        word,
+        missCount: analytics.wordStats[word].incorrect
+      }))
+      .filter(item => item.missCount > 0)
+      .sort((a, b) => b.missCount - a.missCount)
+      .slice(0, 5);
+    
+    analytics.summary.mostMissedWords = missedWords;
+    
+    res.json(analytics);
+  } catch (error) {
+    console.error('Error generating analytics:', error);
+    res.status(500).send('Error generating analytics data');
+  }
+});