Fix AIRAC directory.

Author: JetStream96

LICENSE.txt

@@ -1,4 +1,4 @@
-The navigation data (all files in /QSimPlanner/[Version]/NavData folder) 
+The navigation data (all files in /QSimPlanner/NavData folder) 
 shipped with this program is Aerosoft's property and is under Aerosoft's 
 NavDataPro license.
 

src/Installer/InstallerBuilder/AiracFile.cs

@@ -22,7 +22,14 @@ private static void GetAirac()
                 throw new NotImplementedException();
             }
         }
-        
+
+        /// <summary>
+        /// Note: The consequence of this method means NavData is put into the 
+        /// same directory as QSimPlanner.exe. This is not where it's supposed 
+        /// to be, but it has to stay like this for compatibility with older 
+        /// version. When application starts, the NavData directory will be 
+        /// moved one level up. 
+        /// </summary>
         public static void CopyNavData()
         {
             GetAirac();

src/QSP/Common/Options/AppOptions.cs

@@ -45,7 +45,7 @@ public AppOptions(
         }
 
         public static AppOptions Default => new AppOptions(
-            Path.GetFullPath("NavData"),
+            Path.GetFullPath("../NavData"),
             true,
             true,
             true,

src/QSP/LibraryExtension/IOMethods.cs

@@ -1,4 +1,5 @@
 using System.IO;
+using System.Linq;
 
 namespace QSP.LibraryExtension
 {
@@ -39,5 +40,10 @@ public static void CopyDirectory(DirectoryInfo source,
 
             CopyFilesInDirectory(source, target, overwrite);
         }
+
+        public static bool IsDirectoryEmpty(string path)
+        {
+            return !Directory.EnumerateFileSystemEntries(path).Any();
+        }
     }
 }

src/QSP/Program.cs

@@ -1,5 +1,6 @@
 using CommonLibrary.LibraryExtension;
 using QSP.Common.Options;
+using QSP.LibraryExtension;
 using QSP.LibraryExtension.XmlSerialization;
 using QSP.Properties;
 using QSP.UI.Forms;
@@ -67,6 +68,7 @@ internal static void Main(string[] args)
 #endif
 
                 ShowLicenseIfNeeded();
+                MoveNavData();
                 var mainFrm = new QspForm();
                 mainFrm.Init();
 
@@ -215,6 +217,16 @@ private static void ReportError(string message)
             }
         }
 
+        // See notes in InstallerBuilder/AiracFile.cs, CopyNavData() method.
+        private static void MoveNavData()
+        {
+            var dest = "../NavData";
+            if (!Directory.Exists(dest) || IOMethods.IsDirectoryEmpty(dest))
+            {
+                Directory.Move("NavData", dest);
+            }
+        }
+
         private static string GetGuid()
         {
             var attributes = typeof(Program).Assembly