Pushing missing changes

MediaBrowser.Common/IO/FileSystemRepository.cs

@@ -0,0 +1,211 @@
+using MediaBrowser.Common.Extensions;
+using System;
+using System.Collections.Concurrent;
+using System.IO;
+using System.Threading.Tasks;
+
+namespace MediaBrowser.Common.IO
+{
+    /// <summary>
+    /// This is a wrapper for storing large numbers of files within a directory on a file system.
+    /// Simply pass a filename into GetResourcePath and it will return a full path location of where the file should be stored.
+    /// </summary>
+    public class FileSystemRepository : IDisposable
+    {
+        /// <summary>
+        /// Contains the list of subfolders under the main directory
+        /// The directory entry is created when the item is first added to the dictionary
+        /// </summary>
+        private readonly ConcurrentDictionary<string, string> _subFolderPaths = new ConcurrentDictionary<string, string>();
+
+        /// <summary>
+        /// The _file locks
+        /// </summary>
+        private readonly NamedLock _fileLocks = new NamedLock();
+
+        /// <summary>
+        /// Gets or sets the path.
+        /// </summary>
+        /// <value>The path.</value>
+        protected string Path { get; set; }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="FileSystemRepository" /> class.
+        /// </summary>
+        /// <param name="path">The path.</param>
+        /// <exception cref="System.ArgumentNullException"></exception>
+        public FileSystemRepository(string path)
+        {
+            if (string.IsNullOrEmpty(path))
+            {
+                throw new ArgumentNullException();
+            }
+
+            Path = path;
+            Initialize();
+        }
+
+        /// <summary>
+        /// Initializes this instance.
+        /// </summary>
+        protected void Initialize()
+        {
+            if (!Directory.Exists(Path))
+            {
+                Directory.CreateDirectory(Path);
+            }
+        }
+
+        /// <summary>
+        /// Gets the full path of where a resource should be stored within the repository
+        /// </summary>
+        /// <param name="uniqueName">Name of the unique.</param>
+        /// <param name="fileExtension">The file extension.</param>
+        /// <returns>System.String.</returns>
+        /// <exception cref="System.ArgumentNullException"></exception>
+        public string GetResourcePath(string uniqueName, string fileExtension)
+        {
+            if (string.IsNullOrEmpty(uniqueName))
+            {
+                throw new ArgumentNullException();
+            }
+
+            if (string.IsNullOrEmpty(fileExtension))
+            {
+                throw new ArgumentNullException();
+            }
+            
+            var filename = uniqueName.GetMD5() + fileExtension;
+
+            return GetResourcePath(filename);
+        }
+
+        /// <summary>
+        /// Gets the full path of where a file should be stored within the repository
+        /// </summary>
+        /// <param name="filename">The filename.</param>
+        /// <returns>System.String.</returns>
+        /// <exception cref="System.ArgumentNullException"></exception>
+        public string GetResourcePath(string filename)
+        {
+            if (string.IsNullOrEmpty(filename))
+            {
+                throw new ArgumentNullException();
+            }
+            
+            return GetInternalResourcePath(filename);
+        }
+
+        /// <summary>
+        /// Takes a filename and returns the full path of where it should be stored
+        /// </summary>
+        /// <param name="filename">The filename.</param>
+        /// <returns>System.String.</returns>
+        private string GetInternalResourcePath(string filename)
+        {
+            var prefix = filename.Substring(0, 1);
+
+            var folder = _subFolderPaths.GetOrAdd(prefix, GetCachePath);
+
+            return System.IO.Path.Combine(folder, filename);
+        }
+
+        /// <summary>
+        /// Creates a subfolder under the image cache directory and returns the full path
+        /// </summary>
+        /// <param name="prefix">The prefix.</param>
+        /// <returns>System.String.</returns>
+        private string GetCachePath(string prefix)
+        {
+            var path = System.IO.Path.Combine(Path, prefix);
+
+            if (!Directory.Exists(path))
+            {
+                Directory.CreateDirectory(path);
+            }
+
+            return path;
+        }
+
+        /// <summary>
+        /// Determines if a resource is present in the repository
+        /// </summary>
+        /// <param name="uniqueName">Name of the unique.</param>
+        /// <param name="fileExtension">The file extension.</param>
+        /// <returns><c>true</c> if the specified unique name contains resource; otherwise, <c>false</c>.</returns>
+        public bool ContainsResource(string uniqueName, string fileExtension)
+        {
+            return ContainsFilePath(GetResourcePath(uniqueName, fileExtension));
+        }
+
+        /// <summary>
+        /// Determines if a file with a given name is present in the repository
+        /// </summary>
+        /// <param name="filename">The filename.</param>
+        /// <returns><c>true</c> if the specified filename contains filename; otherwise, <c>false</c>.</returns>
+        /// <exception cref="System.ArgumentNullException"></exception>
+        public bool ContainsFilename(string filename)
+        {
+            if (string.IsNullOrEmpty(filename))
+            {
+                throw new ArgumentNullException();
+            }
+            
+            return ContainsFilePath(GetInternalResourcePath(filename));
+        }
+
+        /// <summary>
+        /// Determines if a file is present in the repository
+        /// </summary>
+        /// <param name="path">The path.</param>
+        /// <returns><c>true</c> if [contains file path] [the specified path]; otherwise, <c>false</c>.</returns>
+        /// <exception cref="System.ArgumentNullException"></exception>
+        public bool ContainsFilePath(string path)
+        {
+            if (string.IsNullOrEmpty(path))
+            {
+                throw new ArgumentNullException();
+            }
+            
+            return File.Exists(path);
+        }
+
+        /// <summary>
+        /// Waits for lock.
+        /// </summary>
+        /// <param name="resourcePath">The resource path.</param>
+        public Task WaitForLockAsync(string resourcePath)
+        {
+            return _fileLocks.WaitAsync(resourcePath);
+        }
+
+        /// <summary>
+        /// Releases the lock.
+        /// </summary>
+        /// <param name="resourcePath">The resource path.</param>
+        public void ReleaseLock(string resourcePath)
+        {
+            _fileLocks.Release(resourcePath);
+        }
+
+        /// <summary>
+        /// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
+        /// </summary>
+        public void Dispose()
+        {
+            Dispose(true);
+        }
+
+        /// <summary>
+        /// Releases unmanaged and - optionally - managed resources.
+        /// </summary>
+        /// <param name="dispose"><c>true</c> to release both managed and unmanaged resources; <c>false</c> to release only unmanaged resources.</param>
+        protected virtual void Dispose(bool dispose)
+        {
+            if (dispose)
+            {
+                _fileLocks.Dispose();
+            }
+        }
+    }
+}