1 files changed, 89 insertions, 0 deletions
diff --git a/MediaBrowser.LocalMetadata/BaseXmlProvider.cs b/MediaBrowser.LocalMetadata/BaseXmlProvider.cs
new file mode 100644
index 000000000..cc9bc7bed
--- /dev/null
+++ b/MediaBrowser.LocalMetadata/BaseXmlProvider.cs
@@ -0,0 +1,89 @@
+using System;
+using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
+using MediaBrowser.Common.IO;
+using MediaBrowser.Controller.Entities;
+using MediaBrowser.Controller.Providers;
+using MediaBrowser.Model.Logging;
+
+namespace MediaBrowser.LocalMetadata
+{
+    public abstract class BaseXmlProvider<T> : ILocalMetadataProvider<T>, IHasChangeMonitor
+        where T : IHasMetadata, new()
+    {
+        protected IFileSystem FileSystem;
+
+        public async Task<LocalMetadataResult<T>> GetMetadata(ItemInfo info, CancellationToken cancellationToken)
+        {
+            var result = new LocalMetadataResult<T>();
+
+            var file = GetXmlFile(info, new DirectoryService(new NullLogger()));
+
+            if (file == null)
+            {
+                return result;
+            }
+
+            var path = file.FullName;
+
+            await XmlProviderUtils.XmlParsingResourcePool.WaitAsync(cancellationToken).ConfigureAwait(false);
+
+            try
+            {
+                result.Item = new T();
+
+                Fetch(result, path, cancellationToken);
+                result.HasMetadata = true;
+            }
+            catch (FileNotFoundException)
+            {
+                result.HasMetadata = false;
+            }
+            catch (DirectoryNotFoundException)
+            {
+                result.HasMetadata = false;
+            }
+            finally
+            {
+                XmlProviderUtils.XmlParsingResourcePool.Release();
+            }
+
+            return result;
+        }
+
+        protected abstract void Fetch(LocalMetadataResult<T> result, string path, CancellationToken cancellationToken);
+
+        protected BaseXmlProvider(IFileSystem fileSystem)
+        {
+            FileSystem = fileSystem;
+        }
+
+        protected abstract FileSystemInfo GetXmlFile(ItemInfo info, IDirectoryService directoryService);
+
+        public bool HasChanged(IHasMetadata item, IDirectoryService directoryService, DateTime date)
+        {
+            var file = GetXmlFile(new ItemInfo { IsInMixedFolder = item.IsInMixedFolder, Path = item.Path }, directoryService);
+
+            if (file == null)
+            {
+                return false;
+            }
+
+            return file.Exists && FileSystem.GetLastWriteTimeUtc(file) > date;
+        }
+
+        public string Name
+        {
+            get
+            {
+                return "Media Browser Xml";
+            }
+        }
+    }
+
+    static class XmlProviderUtils
+    {
+        internal static readonly SemaphoreSlim XmlParsingResourcePool = new SemaphoreSlim(4, 4);
+    }
+}