Implemented the ability to extract an archive image to a cache directory.

API/Interfaces/IDirectoryService.cs

@@ -4,8 +4,38 @@ namespace API.Interfaces
 {
     public interface IDirectoryService
     {
+        /// <summary>
+        /// Lists out top-level folders for a given directory. Filters out System and Hidden folders.
+        /// </summary>
+        /// <param name="rootPath">Absolute path of directory to scan.</param>
+        /// <returns>List of folder names</returns>
         IEnumerable<string> ListDirectory(string rootPath);
 
+        /// <summary>
+        /// Lists out top-level files for a given directory.
+        /// TODO: Implement ability to provide a filter for file types
+        /// </summary>
+        /// <param name="rootPath">Absolute path </param>
+        /// <returns>List of folder names</returns>
+        IEnumerable<string> ListFiles(string rootPath);
+
+        /// <summary>
+        /// Given a library id, scans folders for said library. Parses files and generates DB updates. Will overwrite
+        /// cover images if forceUpdate is true.
+        /// </summary>
+        /// <param name="libraryId">Library to scan against</param>
+        /// <param name="forceUpdate">Force overwriting for cover images</param>
         void ScanLibrary(int libraryId, bool forceUpdate);
+
+        /// <summary>
+        /// Extracts an archive to a temp cache directory. Returns path to new directory. If temp cache directory already exists,
+        /// will return that without performing an extraction. Returns empty string if there are any invalidations which would
+        /// prevent operations to perform correctly (missing archivePath file, empty archive, etc).
+        /// </summary>
+        /// <param name="archivePath">A valid file to an archive file.</param>
+        /// <param name="volumeId">Id of volume being extracted.</param>
+        /// <returns></returns>
+        string ExtractArchive(string archivePath, int volumeId);
+        
     }
 }