Logger now uses one file per session rather than one giant dump

- Old logs are deleted.

MultiTablePro/Data/License.cs

@@ -85,7 +85,7 @@ private void ApiRequest(string path)
             else if (apiResult.result.is_valid == 1)
             {
                 // todo: Set all result properties to class properties
-                Key = apiResult.result.license_key.ToObject<string>());
+                Key = apiResult.result.license_key.ToObject<string>();
                 //...
 
                 // Set activelicense and run application

MultiTablePro/HotKeyHandler.cs

@@ -113,7 +113,7 @@ public static void UnregisterHotKey(HotKey hotKey)
             }
             catch
             {
-                Logger.Log("Attempting to unregister a hotke<y that was never registered.", Logger.Status.Error);
+                Logger.Log("Attempting to unregister a hotkey that was never registered.", Logger.Status.Error);
                 return;
             }
 

MultiTablePro/Logger.cs

@@ -4,6 +4,7 @@
 using System.IO;
 using System.Linq;
 using System.Text;
+using System.Text.RegularExpressions;
 using System.Threading;
 using System.Threading.Tasks;
 using System.Windows;
@@ -17,16 +18,27 @@ static Logger()
             // Set log level
             LogLevel = (Status)Properties.Settings.Default.LogLevel;
 
-            // Determine log file location
+            // Get working AppData Local directory
             string path = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "MultiTablePro");
             if (Debugger.IsAttached) // Seperate directory for debugger
                 path = Path.Combine(path, "Debug");
+
+            // Enter logs subdirectory & create if it doesn't exist.
+            path = Path.Combine(path, "Logs");
             if (!Directory.Exists(path))
                 Directory.CreateDirectory(path);
-            LogFilePath = Path.Combine(path, "output.log");
+
+            // Create log filename with timestamp
+            LogFilePath = Path.Combine(path, string.Format("mtp-{0}.log", DateTime.Now.ToString("yyyy-MM-dd-hh-mm-ss")));
 
             // Start log writer
             new Thread(() => StartLogWriter()).Start();
+
+            // Application exit event
+            Application.Current.Exit += Application_Exit;
+
+            // Clean log files older than 6 months
+            new Thread(() => CleanLogs()).Start();
         }
 
         public enum Status
@@ -85,5 +97,30 @@ private static void StartLogWriter()
                 }
             }
         }
+
+
+        // Removes log files older than 6 months
+        private static void CleanLogs()
+        {
+            string logsDir = Path.GetDirectoryName(LogFilePath);
+
+            // Ensure it's an MTP logfile, not a backup, not some important file that somehow ended up here
+            Regex rValidLogFile = new Regex(@"mtp-\d\d\d\d-\d\d-\d\d-\d\d-\d\d-\d\d.log");
+
+            // Find approperiate files to delete & delete them
+            Directory.EnumerateFiles(logsDir)
+                .Where(s => rValidLogFile.IsMatch(Path.GetFileName(s))) 
+                .Where(s => File.GetCreationTime(s) < DateTime.Now.AddMonths(-6))
+                .ToList() // No foreach in IEnumerable, needs list
+                .ForEach(s => File.Delete(s));
+        }
+
+        private static void Application_Exit(object sender, ExitEventArgs e)
+        {
+            // Delete empty log files when application closes
+            // Also helps to have these empty logfiles as an indication of unclean shutdown
+            if (File.Exists(LogFilePath) && File.ReadAllText(LogFilePath) == "")
+                File.Delete(LogFilePath);
+        }
     }
 }