Added base classes to encapsulate metadata in media

Aurora/Backend/Models/Media/LocalAudio.cs

@@ -0,0 +1,66 @@
+using System;
+using System.IO;
+
+namespace Aurora.Backend.Models.Media
+{
+    public class LocalAudio : BaseMedia
+    {
+        public LocalAudio(FileInfo fileInfo)
+        {
+            File = fileInfo;
+            LoadMetadata();
+        }
+
+        #region Properties
+        public FileInfo File { get; private set; }
+
+        public AudioMetadata Metadata { get; private set; }
+
+        public override MediaTypeEnum MediaType
+        {
+            get { return MediaTypeEnum.Audio; }
+        }
+
+        #endregion Properties
+
+        /// <summary>
+        /// Override load method.
+        /// </summary>
+        public override void Load()
+        {
+            if (this.DataStream != null)
+            {
+                DataStream.Close();
+                DataStream = null;
+            }
+            this.DataStream = System.IO.File.OpenRead(File.FullName);
+            base.Load();
+        }
+
+        /// <summary>
+        /// Override unload method
+        /// </summary>
+        public override void Unload()
+        {
+            if (this.DataStream != null)
+            {
+                DataStream.Close();
+                DataStream = null;
+            }
+            base.Unload();
+        }
+
+        private void LoadMetadata()
+        {
+            TagLib.File tagFile = TagLib.File.Create(File.FullName);
+
+            Metadata = new AudioMetadata()
+            {
+                Title = tagFile.Tag.Title,
+                Album = tagFile.Tag.Album,
+                Artist = tagFile.Tag.FirstAlbumArtist,
+                ExtraData = tagFile.Tag
+            };
+        }
+    }
+}