1 files changed, 99 insertions, 0 deletions
diff --git a/MediaBrowser.Common.Implementations/Devices/DeviceId.cs b/MediaBrowser.Common.Implementations/Devices/DeviceId.cs
new file mode 100644
index 000000000..ce69843fb
--- /dev/null
+++ b/MediaBrowser.Common.Implementations/Devices/DeviceId.cs
@@ -0,0 +1,99 @@
+using MediaBrowser.Common.Configuration;
+using MediaBrowser.Model.Logging;
+using System;
+using System.IO;
+using System.Text;
+
+namespace MediaBrowser.Common.Implementations.Devices
+{
+    public class DeviceId
+    {
+        private readonly IApplicationPaths _appPaths;
+        private readonly ILogger _logger;
+
+        private readonly object _syncLock = new object();
+
+        private string CachePath
+        {
+            get { return Path.Combine(_appPaths.DataPath, "device.txt"); }
+        }
+
+        private string GetCachedId()
+        {
+            try
+            {
+                lock (_syncLock)
+                {
+                    var value = File.ReadAllText(CachePath, Encoding.UTF8);
+
+                    Guid guid;
+                    if (Guid.TryParse(value, out guid))
+                    {
+                        return value;
+                    }
+
+                    _logger.Error("Invalid value found in device id file");
+                }
+            }
+            catch (FileNotFoundException ex)
+            {
+            }
+            catch (Exception ex)
+            {
+                _logger.ErrorException("Error reading file", ex);
+            }
+
+            return null;
+        }
+
+        private void SaveId(string id)
+        {
+            try
+            {
+                var path = CachePath;
+
+                Directory.CreateDirectory(Path.GetDirectoryName(path));
+
+                lock (_syncLock)
+                {
+                    File.WriteAllText(path, id, Encoding.UTF8);
+                }
+            }
+            catch (Exception ex)
+            {
+                _logger.ErrorException("Error writing to file", ex);
+            }
+        }
+
+        private string GetNewId()
+        {
+            return Guid.NewGuid().ToString("N");
+        }
+
+        private string GetDeviceId()
+        {
+            var id = GetCachedId();
+
+            if (string.IsNullOrWhiteSpace(id))
+            {
+                id = GetNewId();
+                SaveId(id);
+            }
+
+            return id;
+        }
+
+        private string _id;
+
+        public DeviceId(IApplicationPaths appPaths, ILogger logger)
+        {
+            _appPaths = appPaths;
+            _logger = logger;
+        }
+
+        public string Value
+        {
+            get { return _id ?? (_id = GetDeviceId()); }
+        }
+    }
+}