// using System.Diagnostics.CodeAnalysis;
// using LocalModels;

// public class FileStorageManagerCached : IFileStorageManager
// {
//   private readonly FileStorageManager manager;

//   private readonly object cacheLock = new object();  // Lock object for synchronization


//   private DateTime? cacheTime { get; set; } = null;
//   private IEnumerable<LocalCourse>? cachedCourses { get; set; } = null;
//   private ILogger<FileStorageManagerCached> logger { get; }

//   private readonly int cacheSeconds = 2;
//   public FileStorageManagerCached(FileStorageManager manager, ILogger<FileStorageManagerCached> logger)
//   {
//     this.manager = manager;
//     this.logger = logger;
//   }
//   public Task<IEnumerable<string>> GetEmptyDirectories()
//   {
//     return manager.GetEmptyDirectories();
//   }

//   public async Task<IEnumerable<LocalCourse>> LoadSavedCourses()
//   {

//     var secondsFromLastLoad = (DateTime.Now - cacheTime)?.Seconds;

//     if (cachedCourses != null && secondsFromLastLoad < cacheSeconds)
//     {
//       logger.LogInformation("returning cached courses from file");
//       return cachedCourses;
//     }

//     cachedCourses = await manager.LoadSavedCourses();
//     cacheTime = DateTime.Now;
//     return cachedCourses;
//   }

//   public async Task SaveCourseAsync(LocalCourse course, LocalCourse? previouslyStoredCourse)
//   {
//     // race condition...
//     cacheTime = null;
//     cachedCourses = null;
//     await manager.SaveCourseAsync(course, previouslyStoredCourse);
//   }
// }