Fix the upgrade of the configuration file with available legacy file

Author: Fighter456

PatternFileMover/Form1.cs

@@ -30,10 +30,20 @@ public Form1()
             // ensure the existance of the necessary config file
             if (!File.Exists(NameAssociations.configManifestPath))
             {
-                // file not found
-                // typically at the first usage of the program
-                // create an empty config file
-                NameAssociations.CreateEmptyConfigFile();
+                // the manifest file hasn't been found…
+                if (File.Exists(NameAssociations.legacyConfigPath))
+                {
+                    // … but there is a legacy config file
+                    // that means that we need to convert a `v1` config file
+                    NameAssociations.checkAndUpgradeConfigurationFile(true);
+                }
+                else 
+                {
+                    // file not found
+                    // typically at the first usage of the program
+                    // create an empty config file
+                    NameAssociations.CreateEmptyConfigFile();
+                }
             }
             else
             {

PatternFileMover/NameAssociations.cs

@@ -37,7 +37,12 @@ public static string GetConfigFilePath()
                     ".json";
         }
 
-        public static void checkAndUpgradeConfigurationFile() {
+        public static void checkAndUpgradeConfigurationFile(bool isV1 = false) {
+            if (isV1 == true)
+            {
+                File.WriteAllText(configManifestPath, "v1");
+            }
+
             string manifestVersion = File.ReadAllText(Path.GetFullPath(configManifestPath));
 
             if (!File.Exists(Path.GetFullPath(GetConfigFilePath())))
@@ -62,6 +67,7 @@ public static void checkAndUpgradeConfigurationFile() {
                         });
                     }
 
+                    File.WriteAllText(configManifestPath, "v2");
                     WriteByList(convertedValues);
                 }
             }