updated

dashboard/public/index.html

@@ -203,14 +203,24 @@
             updateUrlParams();
         }
 
-        async function loadStatistics() {
+        async function loadStatistics(forceReload = false) {
             const days = parseInt(document.getElementById('statisticsPeriod')?.value || '7');
-            // Lade die Graphen (ohne fetchData aufzurufen, um Zucken zu vermeiden)
-            await Promise.all([
-                loadMovingAverage(days),
-                loadVolumeChanges(days),
-                loadStockTrends(days)
-            ]);
+            
+            // Beim ersten Laden oder bei expliziter Anforderung: Daten laden
+            if (forceReload || !store.trades || store.trades.length === 0) {
+                await fetchData(true); // skipCharts = true, damit Graphen nicht doppelt geladen werden
+            }
+            
+            // Lade die Graphen
+            try {
+                await Promise.all([
+                    loadMovingAverage(days),
+                    loadVolumeChanges(days),
+                    loadStockTrends(days)
+                ]);
+            } catch (err) {
+                console.error('Error loading statistics:', err);
+            }
             updateUrlParams();
         }
 
@@ -225,7 +235,12 @@
                     return;
                 }
                 
-                const ctx = document.getElementById('movingAverageChart').getContext('2d');
+                const canvas = document.getElementById('movingAverageChart');
+                if (!canvas) {
+                    console.error('Canvas element movingAverageChart not found');
+                    return;
+                }
+                const ctx = canvas.getContext('2d');
                 if (charts.movingAverage) charts.movingAverage.destroy();
                 
                 const dateIdx = columns.findIndex(c => c.name === 'date' || c.name === 'timestamp');
@@ -340,7 +355,12 @@
                     return;
                 }
                 
-                const ctx = document.getElementById('volumeChangesChart').getContext('2d');
+                const canvas = document.getElementById('volumeChangesChart');
+                if (!canvas) {
+                    console.error('Canvas element volumeChangesChart not found');
+                    return;
+                }
+                const ctx = canvas.getContext('2d');
                 if (charts.volumeChanges) charts.volumeChanges.destroy();
                 
                 const exchangeIdx = columns.findIndex(c => c.name === 'exchange');
@@ -425,7 +445,12 @@
                     return;
                 }
                 
-                const ctx = document.getElementById('stockTrendsChart').getContext('2d');
+                const canvas = document.getElementById('stockTrendsChart');
+                if (!canvas) {
+                    console.error('Canvas element stockTrendsChart not found');
+                    return;
+                }
+                const ctx = canvas.getContext('2d');
                 const tableContainer = document.getElementById('stockTrendsTable');
                 
                 if (charts.stockTrends) charts.stockTrends.destroy();
@@ -747,7 +772,8 @@
                 fetchData(true); // skipCharts = true
             }, 30000);
             
-            setTimeout(() => loadStatistics(), 1000);
+            // Lade Statistiken nach kurzer Verzögerung (forceReload = true beim ersten Laden)
+            setTimeout(() => loadStatistics(true), 1000);
         };
     </script>
 </body>