Projektdateien hinzufügen.

BackEnd/Logger.cs

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+using System.Collections.ObjectModel;
+using System.IO;
+
+namespace ReSync
+{
+    public class Logger
+    {
+        private readonly string _logFilePath;
+        public ObservableCollection<LogEntry> Entries { get; } = new();
+
+        public Logger(string logFilePath)
+        {
+            _logFilePath = logFilePath;
+            Directory.CreateDirectory(Path.GetDirectoryName(logFilePath)!);
+        }
+
+        public void Log(string message, string level = "Info")
+        {
+            var entry = new LogEntry { Message = message, Level = level };
+            App.Current.Dispatcher.Invoke(() => Entries.Add(entry)); // update UI safely
+
+            var line = $"{entry.Timestamp:yyyy-MM-dd HH:mm:ss} [{entry.Level}] {entry.Message}";
+            File.AppendAllText(_logFilePath, line + Environment.NewLine);
+        }
+
+        public void Clear()
+        {
+            Entries.Clear();
+            File.WriteAllText(_logFilePath, "");
+        }
+    }
+
+    public class LogEntry
+    {
+        public DateTime Timestamp { get; set; } = DateTime.Now;
+        public string Level { get; set; } = "Info";
+        public string Message { get; set; } = "";
+    }
+}