replace file system calls with IFileSystem when needed

1 files changed, 342 insertions, 0 deletions

diff --git a/MediaBrowser.Common.Implementations/IO/CommonFileSystem.cs b/MediaBrowser.Common.Implementations/IO/CommonFileSystem.cs
new file mode 100644
index 000000000..ed9baf3b2
--- /dev/null
+++ b/MediaBrowser.Common.Implementations/IO/CommonFileSystem.cs
@@ -0,0 +1,342 @@
+using MediaBrowser.Common.IO;
+using MediaBrowser.Model.Logging;
+using System;
+using System.IO;
+using System.Text;
+
+namespace MediaBrowser.Common.Implementations.IO
+{
+    /// <summary>
+    /// Class CommonFileSystem
+    /// </summary>
+    public class CommonFileSystem : IFileSystem
+    {
+        protected ILogger Logger;
+
+        private readonly bool _supportsAsyncFileStreams;
+
+        public CommonFileSystem(ILogger logger, bool supportsAsyncFileStreams)
+        {
+            Logger = logger;
+            _supportsAsyncFileStreams = supportsAsyncFileStreams;
+        }
+
+        /// <summary>
+        /// Determines whether the specified filename is shortcut.
+        /// </summary>
+        /// <param name="filename">The filename.</param>
+        /// <returns><c>true</c> if the specified filename is shortcut; otherwise, <c>false</c>.</returns>
+        /// <exception cref="System.ArgumentNullException">filename</exception>
+        public virtual bool IsShortcut(string filename)
+        {
+            if (string.IsNullOrEmpty(filename))
+            {
+                throw new ArgumentNullException("filename");
+            }
+
+            var extension = Path.GetExtension(filename);
+
+            return string.Equals(extension, ".mblink", StringComparison.OrdinalIgnoreCase);
+        }
+
+        /// <summary>
+        /// Resolves the shortcut.
+        /// </summary>
+        /// <param name="filename">The filename.</param>
+        /// <returns>System.String.</returns>
+        /// <exception cref="System.ArgumentNullException">filename</exception>
+        public virtual string ResolveShortcut(string filename)
+        {
+            if (string.IsNullOrEmpty(filename))
+            {
+                throw new ArgumentNullException("filename");
+            }
+
+            if (string.Equals(Path.GetExtension(filename), ".mblink", StringComparison.OrdinalIgnoreCase))
+            {
+                return File.ReadAllText(filename);
+            }
+
+            return null;
+        }
+
+        /// <summary>
+        /// Creates the shortcut.
+        /// </summary>
+        /// <param name="shortcutPath">The shortcut path.</param>
+        /// <param name="target">The target.</param>
+        /// <exception cref="System.ArgumentNullException">
+        /// shortcutPath
+        /// or
+        /// target
+        /// </exception>
+        public void CreateShortcut(string shortcutPath, string target)
+        {
+            if (string.IsNullOrEmpty(shortcutPath))
+            {
+                throw new ArgumentNullException("shortcutPath");
+            }
+
+            if (string.IsNullOrEmpty(target))
+            {
+                throw new ArgumentNullException("target");
+            }
+
+            File.WriteAllText(shortcutPath, target);
+        }
+
+        /// <summary>
+        /// Gets the file system info.
+        /// </summary>
+        /// <param name="path">The path.</param>
+        /// <returns>FileSystemInfo.</returns>
+        public FileSystemInfo GetFileSystemInfo(string path)
+        {
+            // Take a guess to try and avoid two file system hits, but we'll double-check by calling Exists
+            if (Path.HasExtension(path))
+            {
+                var fileInfo = new FileInfo(path);
+
+                if (fileInfo.Exists)
+                {
+                    return fileInfo;
+                }
+
+                return new DirectoryInfo(path);
+            }
+            else
+            {
+                var fileInfo = new DirectoryInfo(path);
+
+                if (fileInfo.Exists)
+                {
+                    return fileInfo;
+                }
+
+                return new FileInfo(path);
+            }
+        }
+
+        /// <summary>
+        /// The space char
+        /// </summary>
+        private const char SpaceChar = ' ';
+        /// <summary>
+        /// The invalid file name chars
+        /// </summary>
+        private static readonly char[] InvalidFileNameChars = Path.GetInvalidFileNameChars();
+
+        /// <summary>
+        /// Takes a filename and removes invalid characters
+        /// </summary>
+        /// <param name="filename">The filename.</param>
+        /// <returns>System.String.</returns>
+        /// <exception cref="System.ArgumentNullException">filename</exception>
+        public string GetValidFilename(string filename)
+        {
+            if (string.IsNullOrEmpty(filename))
+            {
+                throw new ArgumentNullException("filename");
+            }
+
+            var builder = new StringBuilder(filename);
+
+            foreach (var c in InvalidFileNameChars)
+            {
+                builder = builder.Replace(c, SpaceChar);
+            }
+
+            return builder.ToString();
+        }
+
+        /// <summary>
+        /// Gets the creation time UTC.
+        /// </summary>
+        /// <param name="info">The info.</param>
+        /// <returns>DateTime.</returns>
+        public DateTime GetCreationTimeUtc(FileSystemInfo info)
+        {
+            // This could throw an error on some file systems that have dates out of range
+            try
+            {
+                return info.CreationTimeUtc;
+            }
+            catch (Exception ex)
+            {
+                Logger.ErrorException("Error determining CreationTimeUtc for {0}", ex, info.FullName);
+                return DateTime.MinValue;
+            }
+        }
+
+        /// <summary>
+        /// Gets the creation time UTC.
+        /// </summary>
+        /// <param name="info">The info.</param>
+        /// <param name="logger">The logger.</param>
+        /// <returns>DateTime.</returns>
+        public DateTime GetLastWriteTimeUtc(FileSystemInfo info)
+        {
+            // This could throw an error on some file systems that have dates out of range
+            try
+            {
+                return info.LastWriteTimeUtc;
+            }
+            catch (Exception ex)
+            {
+                Logger.ErrorException("Error determining LastAccessTimeUtc for {0}", ex, info.FullName);
+                return DateTime.MinValue;
+            }
+        }
+
+        /// <summary>
+        /// Gets the last write time UTC.
+        /// </summary>
+        /// <param name="path">The path.</param>
+        /// <returns>DateTime.</returns>
+        public DateTime GetLastWriteTimeUtc(string path)
+        {
+            return GetLastWriteTimeUtc(GetFileSystemInfo(path));
+        }
+
+        /// <summary>
+        /// Gets the file stream.
+        /// </summary>
+        /// <param name="path">The path.</param>
+        /// <param name="mode">The mode.</param>
+        /// <param name="access">The access.</param>
+        /// <param name="share">The share.</param>
+        /// <param name="isAsync">if set to <c>true</c> [is asynchronous].</param>
+        /// <returns>FileStream.</returns>
+        public FileStream GetFileStream(string path, FileMode mode, FileAccess access, FileShare share, bool isAsync = false)
+        {
+            if (_supportsAsyncFileStreams && isAsync)
+            {
+                return new FileStream(path, mode, access, share, 4096, true);
+            }
+
+            return new FileStream(path, mode, access, share);
+        }
+    }
+
+    /// <summary>
+    ///  Adapted from http://stackoverflow.com/questions/309495/windows-shortcut-lnk-parser-in-java
+    /// </summary>
+    internal class WindowsShortcut
+    {
+        public bool IsDirectory { get; private set; }
+        public bool IsLocal { get; private set; }
+        public string ResolvedPath { get; private set; }
+
+        public WindowsShortcut(string file)
+        {
+            ParseLink(File.ReadAllBytes(file), Encoding.UTF8);
+        }
+
+        private static bool isMagicPresent(byte[] link)
+        {
+
+            const int magic = 0x0000004C;
+            const int magic_offset = 0x00;
+
+            return link.Length >= 32 && bytesToDword(link, magic_offset) == magic;
+        }
+
+        /**
+         * Gobbles up link data by parsing it and storing info in member fields
+         * @param link all the bytes from the .lnk file
+         */
+        private void ParseLink(byte[] link, Encoding encoding)
+        {
+            if (!isMagicPresent(link))
+                throw new IOException("Invalid shortcut; magic is missing", 0);
+
+            // get the flags byte
+            byte flags = link[0x14];
+
+            // get the file attributes byte
+            const int file_atts_offset = 0x18;
+            byte file_atts = link[file_atts_offset];
+            byte is_dir_mask = (byte)0x10;
+            if ((file_atts & is_dir_mask) > 0)
+            {
+                IsDirectory = true;
+            }
+            else
+            {
+                IsDirectory = false;
+            }
+
+            // if the shell settings are present, skip them
+            const int shell_offset = 0x4c;
+            const byte has_shell_mask = (byte)0x01;
+            int shell_len = 0;
+            if ((flags & has_shell_mask) > 0)
+            {
+                // the plus 2 accounts for the length marker itself
+                shell_len = bytesToWord(link, shell_offset) + 2;
+            }
+
+            // get to the file settings
+            int file_start = 0x4c + shell_len;
+
+            const int file_location_info_flag_offset_offset = 0x08;
+            int file_location_info_flag = link[file_start + file_location_info_flag_offset_offset];
+            IsLocal = (file_location_info_flag & 2) == 0;
+            // get the local volume and local system values
+            //final int localVolumeTable_offset_offset = 0x0C;
+            const int basename_offset_offset = 0x10;
+            const int networkVolumeTable_offset_offset = 0x14;
+            const int finalname_offset_offset = 0x18;
+            int finalname_offset = link[file_start + finalname_offset_offset] + file_start;
+            String finalname = getNullDelimitedString(link, finalname_offset, encoding);
+            if (IsLocal)
+            {
+                int basename_offset = link[file_start + basename_offset_offset] + file_start;
+                String basename = getNullDelimitedString(link, basename_offset, encoding);
+                ResolvedPath = basename + finalname;
+            }
+            else
+            {
+                int networkVolumeTable_offset = link[file_start + networkVolumeTable_offset_offset] + file_start;
+                int shareName_offset_offset = 0x08;
+                int shareName_offset = link[networkVolumeTable_offset + shareName_offset_offset]
+                    + networkVolumeTable_offset;
+                String shareName = getNullDelimitedString(link, shareName_offset, encoding);
+                ResolvedPath = shareName + "\\" + finalname;
+            }
+        }
+
+        private static string getNullDelimitedString(byte[] bytes, int off, Encoding encoding)
+        {
+            int len = 0;
+
+            // count bytes until the null character (0)
+            while (true)
+            {
+                if (bytes[off + len] == 0)
+                {
+                    break;
+                }
+                len++;
+            }
+
+            return encoding.GetString(bytes, off, len);
+        }
+
+        /*
+         * convert two bytes into a short note, this is little endian because it's
+         * for an Intel only OS.
+         */
+        private static int bytesToWord(byte[] bytes, int off)
+        {
+            return ((bytes[off + 1] & 0xff) << 8) | (bytes[off] & 0xff);
+        }
+
+        private static int bytesToDword(byte[] bytes, int off)
+        {
+            return (bytesToWord(bytes, off + 2) << 16) | bytesToWord(bytes, off);
+        }
+
+    }
+
+}