Fix invalid export path causing exceptions.

src/QSP/ChangeLog.txt

@@ -1,4 +1,7 @@
-version 0.4.5
+version 0.4.6
+* Hot fix for flight plan export path issue that prevents the program from starting.
+
+version 0.4.5
 * Add several flight plan export formats: Aerosoft Airbus, Flight Factor 777, Flight Factor A320, Ifly 737, Ifly 747 v2, JarDesign Airbus, Pmdg wind uplink, X-plane.
 * Fix Google map API key issue.
 * Minor UI adjustments.

src/QSP/Properties/AssemblyInfo.cs

@@ -31,5 +31,5 @@
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("0.4.5.0")]
+[assembly: AssemblyVersion("0.4.6.0")]
 [assembly: AssemblyFileVersion("1.0.0.0")]

src/QSP/RouteFinding/FileExport/FileExporter.cs

@@ -51,7 +51,7 @@ public IEnumerable<Status> Export()
         // Find a file name which allows us to export without name conflicts.
         private int FileNameNum(IReadOnlyList<ExportCommand> cmdToExport, string nameBase)
         {
-            const int maxAttemptCount = 10000;
+            const int maxAttemptCount = 1000;
             for (int i = 1; i <= maxAttemptCount; i++)
             {
                 if (cmdToExport.All(c => !FileExist(nameBase, c, i))) return i;
@@ -62,10 +62,10 @@ private int FileNameNum(IReadOnlyList<ExportCommand> cmdToExport, string nameBas
 
         private Status Export(string nameBase, ExportCommand c, int i)
         {
-            var fileName = GetFileFullPath(nameBase, c, i);
-
             try
             {
+                var fileName = GetFileFullPath(nameBase, c, i);
+
                 // Although the file name has been checked to have no conflict, if the user choose
                 // to export multiple files to the same folder, the file names can still collide.
                 var newName = File.Exists(fileName)
@@ -94,10 +94,14 @@ private static string GenerateFileName(string nameBase, ExportCommand c)
 
         private bool FileExist(string nameBase, ExportCommand cmd, int n)
         {
-            var filePath = GetFileFullPath(nameBase, cmd, n);
-            return File.Exists(filePath);
+            return DefaultIfThrows(() =>
+            {
+                var filePath = GetFileFullPath(nameBase, cmd, n);
+                return File.Exists(filePath);
+            }, false);
         }
 
+        /// Returned path may be null or not exist.
         private string ExportDirectory(ExportCommand c) =>
             Providers.Types.ExportDirectory(c.DefaultSimulator, c, options());
 
@@ -109,6 +113,7 @@ private void TryCreateDirectories(IEnumerable<ExportCommand> enabledCommands)
             }
         }
 
+        // May throw exception. Returned path may not exist.
         private string GetFileFullPath(string nameBase, ExportCommand cmd, int n)
         {
             var fileName = nameBase + n.ToString().PadLeft(2, '0') + cmd.Extension;

src/QSP/RouteFinding/FileExport/IExportPath.cs

@@ -1,11 +1,14 @@
 using QSP.Common.Options;
+using QSP.Utilities;
 using System.IO;
 
 namespace QSP.RouteFinding.FileExport
 {
     public interface IExportPath
     {
         /// <summary>
+        /// The returned path may be null, if the root directory of
+        /// the given simulator is not set in AppOptions.
         /// The returned path may not exist.
         /// </summary>
         string FullPath(SimulatorType Type, AppOptions Option);
@@ -29,7 +32,16 @@ public class RelativePath : IExportPath
     {
         private readonly string relativePath;
         public RelativePath(string relativePath) { this.relativePath = relativePath; }
-        public string FullPath(SimulatorType Type, AppOptions Option) =>
-            Path.GetFullPath(Path.Combine(Option.SimulatorPaths[Type], relativePath));
+
+        /// <summary>
+        /// Return value may be null, or the path may not exist.
+        /// </summary>
+        public string FullPath(SimulatorType Type, AppOptions Option)
+        {
+            var simPath = Option.SimulatorPaths[Type];
+            return ExceptionHelpers.DefaultIfThrows(
+                 () => Path.GetFullPath(Path.Combine(simPath, relativePath)),
+                 null);
+        }
     }
 }

src/QSP/RouteFinding/FileExport/Providers/Types.cs

@@ -212,7 +212,8 @@ public static string GetExportText(ProviderType type, Route route,
             return Lookup[type].Export(input);
         }
 
-        public static readonly IReadOnlyDictionary<SimulatorType, string> SimDisplayName = Dict
+        public static readonly IReadOnlyDictionary<SimulatorType, string> SimDisplayName = 
+            Dict
         (
             (SimulatorType.FSX, "FSX"),
             (SimulatorType.FSX_Steam, "FSX: Steam edition"),
@@ -226,6 +227,7 @@ public static string GetExportText(ProviderType type, Route route,
 
         /// <summary>
         /// Gets the export directory for the specified simulator.
+        /// Returned path may be null or not exist.
         /// </summary>
         /// <param name="sim">null if using the custom export directory</param>
         /// <exception cref="Exception">The ExportCommand does not support

src/QSP/UI/UserControls/ExportMenuRow.cs

@@ -42,6 +42,7 @@ private SimulatorType? SelectedSimType
             }
         }
 
+        // Returned path may be null or not exist.
         private string GetDirectoryPath()
         {
             var simType = SelectedSimType;
@@ -71,12 +72,13 @@ public void Init(ExportCommand c, Func<AppOptions> option)
                 BrowseBtnEnabled = SimComboBox.SelectedIndex == SimComboBox.Items.Count - 1;
 
                 var path = GetDirectoryPath();
-                PathTextBox.Text = Directory.Exists(path) ? path : "";
+                var pathValid = path != null;
+                PathTextBox.Text = pathValid ? path : "";
             };
 
             SimComboBox.SetItems(sims);
             if (sims.Length > 0) SimComboBox.SelectedIndex = 0;
-            SimComboBox.Text = c.DefaultSimulator == null ? Custom:
+            SimComboBox.Text = c.DefaultSimulator == null ? Custom :
                 SimDisplayName[c.DefaultSimulator.Value];
 
             FileFolderBrowse.LinkFolderBrowse(BrowseBtn, PathTextBox);