NoteFileFormat: Refactor

Get all the allowed extensions in one place. Currently the code is
scattered all over the place.

assets/langs/en.yaml

@@ -268,7 +268,7 @@ widgets:
 rootFolder: Root Folder
 ignoredFiles:
   dot: Starts with a .
-  ext: Doesn't end with .md or .txt
+  ext: Doesn't end with one of the following -
 drawer:
   setup: Setup Git Host
   pro: Unlock Pro Version

lib/core/note.dart

@@ -36,6 +36,34 @@ enum NoteType {
   Journal,
 }
 
+class NoteFileFormatInfo {
+  static List<String> allowedExtensions() {
+    return [
+      '.md',
+      '.txt',
+    ];
+  }
+
+  static String defaultExtension(NoteFileFormat format) {
+    switch (format) {
+      case NoteFileFormat.Markdown:
+        return ".md";
+      case NoteFileFormat.Txt:
+        return ".txt";
+      default:
+        return ".md";
+    }
+  }
+
+  static bool isAllowedFileName(String filePath) {
+    var noteFilePath = filePath.toLowerCase();
+    var isMarkdownFile = noteFilePath.endsWith('.md');
+    var isTxtFile = noteFilePath.endsWith('.txt');
+
+    return isMarkdownFile || isTxtFile;
+  }
+}
+
 enum NoteFileFormat {
   Markdown,
   Txt,

lib/core/notes_folder_fs.dart

@@ -250,13 +250,12 @@ class NotesFolderFS with NotesFolderNotifier implements NotesFolder {
         });
         continue;
       }
-      var noteFilePath = note.filePath.toLowerCase();
-      var isMarkdownFile = noteFilePath.endsWith('.md');
-      var isTxtFile = noteFilePath.endsWith('.txt');
-      if (!isMarkdownFile && !isTxtFile) {
+      if (!NoteFileFormatInfo.isAllowedFileName(note.filePath)) {
         var ignoredFile = IgnoredFile(
           filePath: fsEntity.path,
-          reason: tr("ignoredFiles.ext"),
+          reason: tr("ignoredFiles.ext") +
+              " " +
+              NoteFileFormatInfo.allowedExtensions().join(' '),
         );
         _ignoredFiles.add(ignoredFile);