/*  Copyright (C) 2008-2016 Peter Palotas, Jeffrey Jangli, Alexandr Normuradov
 *  
 *  Permission is hereby granted, free of charge, to any person obtaining a copy 
 *  of this software and associated documentation files (the "Software"), to deal 
 *  in the Software without restriction, including without limitation the rights 
 *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 
 *  copies of the Software, and to permit persons to whom the Software is 
 *  furnished to do so, subject to the following conditions:
 *  
 *  The above copyright notice and this permission notice shall be included in 
 *  all copies or substantial portions of the Software.
 *  
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
 *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
 *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
 *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
 *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
 *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 
 *  THE SOFTWARE. 
 */

using System;
using System.IO;
using System.Security;

namespace Alphaleonis.Win32.Filesystem
{
   partial class Directory
   {
      #region Decrypt

      /// <summary>[AlphaFS] Decrypts a directory that was encrypted by the current account using the Encrypt method.</summary>
      /// <exception cref="ArgumentException"/>
      /// <exception cref="ArgumentNullException"/>
      /// <exception cref="DirectoryNotFoundException"/>
      /// <exception cref="IOException"/>
      /// <exception cref="NotSupportedException"/>
      /// <exception cref="UnauthorizedAccessException"/>
      /// <param name="path">A path that describes a directory to decrypt.</param>
      /// <param name="pathFormat">Indicates the format of the path parameter(s).</param>
      [SecurityCritical]
      public static void Decrypt(string path, PathFormat pathFormat)
      {
         EncryptDecryptDirectoryCore(path, false, false, pathFormat);
      }

      /// <summary>[AlphaFS] Decrypts a directory that was encrypted by the current account using the Encrypt method.</summary>
      /// <exception cref="ArgumentException"/>
      /// <exception cref="ArgumentNullException"/>
      /// <exception cref="DirectoryNotFoundException"/>
      /// <exception cref="IOException"/>
      /// <exception cref="NotSupportedException"/>
      /// <exception cref="UnauthorizedAccessException"/>
      /// <param name="path">A path that describes a directory to decrypt.</param>
      /// <param name="recursive"><see langword="true"/> to decrypt the directory recursively. <see langword="false"/> only decrypt the directory.</param>
      /// <param name="pathFormat">Indicates the format of the path parameter(s).</param>
      [SecurityCritical]
      public static void Decrypt(string path, bool recursive, PathFormat pathFormat)
      {
         EncryptDecryptDirectoryCore(path, false, recursive, pathFormat);
      }

      /// <summary>[AlphaFS] Decrypts a directory that was encrypted by the current account using the Encrypt method.</summary>
      /// <exception cref="ArgumentException"/>
      /// <exception cref="ArgumentNullException"/>
      /// <exception cref="DirectoryNotFoundException"/>
      /// <exception cref="IOException"/>
      /// <exception cref="NotSupportedException"/>
      /// <exception cref="UnauthorizedAccessException"/>
      /// <param name="path">A path that describes a directory to decrypt.</param>
      [SecurityCritical]
      public static void Decrypt(string path)
      {
         EncryptDecryptDirectoryCore(path, false, false, PathFormat.RelativePath);
      }

      /// <summary>[AlphaFS] Decrypts a directory that was encrypted by the current account using the Encrypt method.</summary>
      /// <exception cref="ArgumentException"/>
      /// <exception cref="ArgumentNullException"/>
      /// <exception cref="DirectoryNotFoundException"/>
      /// <exception cref="IOException"/>
      /// <exception cref="NotSupportedException"/>
      /// <exception cref="UnauthorizedAccessException"/>
      /// <param name="path">A path that describes a directory to decrypt.</param>
      /// <param name="recursive"><see langword="true"/> to decrypt the directory recursively. <see langword="false"/> only decrypt the directory.</param>
      [SecurityCritical]
      public static void Decrypt(string path, bool recursive)
      {
         EncryptDecryptDirectoryCore(path, false, recursive, PathFormat.RelativePath);
      }

      #endregion // Decrypt

      #region Encrypt

      /// <summary>[AlphaFS] Encrypts a directory so that only the account used to encrypt the directory can decrypt it.</summary>
      /// <exception cref="ArgumentException"/>
      /// <exception cref="ArgumentNullException"/>
      /// <exception cref="DirectoryNotFoundException"/>
      /// <exception cref="IOException"/>
      /// <exception cref="NotSupportedException"/>
      /// <exception cref="UnauthorizedAccessException"/>
      /// <param name="path">A path that describes a directory to encrypt.</param>
      /// <param name="pathFormat">Indicates the format of the path parameter(s).</param>
      [SecurityCritical]
      public static void Encrypt(string path, PathFormat pathFormat)
      {
         EncryptDecryptDirectoryCore(path, true, false, pathFormat);
      }

      /// <summary>[AlphaFS] Encrypts a directory so that only the account used to encrypt the directory can decrypt it.</summary>
      /// <exception cref="ArgumentException"/>
      /// <exception cref="ArgumentNullException"/>
      /// <exception cref="DirectoryNotFoundException"/>
      /// <exception cref="IOException"/>
      /// <exception cref="NotSupportedException"/>
      /// <exception cref="UnauthorizedAccessException"/>
      /// <param name="path">A path that describes a directory to encrypt.</param>
      /// <param name="recursive"><see langword="true"/> to encrypt the directory recursively. <see langword="false"/> only encrypt the directory.</param>
      /// <param name="pathFormat">Indicates the format of the path parameter(s).</param>
      [SecurityCritical]
      public static void Encrypt(string path, bool recursive, PathFormat pathFormat)
      {
         EncryptDecryptDirectoryCore(path, true, recursive, pathFormat);
      }


      /// <summary>[AlphaFS] Encrypts a directory so that only the account used to encrypt the directory can decrypt it.</summary>
      /// <exception cref="ArgumentException"/>
      /// <exception cref="ArgumentNullException"/>
      /// <exception cref="DirectoryNotFoundException"/>
      /// <exception cref="IOException"/>
      /// <exception cref="NotSupportedException"/>
      /// <exception cref="UnauthorizedAccessException"/>
      /// <param name="path">A path that describes a directory to encrypt.</param>
      [SecurityCritical]
      public static void Encrypt(string path)
      {
         EncryptDecryptDirectoryCore(path, true, false, PathFormat.RelativePath);
      }

      /// <summary>[AlphaFS] Encrypts a directory so that only the account used to encrypt the directory can decrypt it.</summary>
      /// <exception cref="ArgumentException"/>
      /// <exception cref="ArgumentNullException"/>
      /// <exception cref="DirectoryNotFoundException"/>
      /// <exception cref="IOException"/>
      /// <exception cref="NotSupportedException"/>
      /// <exception cref="UnauthorizedAccessException"/>
      /// <param name="path">A path that describes a directory to encrypt.</param>
      /// <param name="recursive"><see langword="true"/> to encrypt the directory recursively. <see langword="false"/> only encrypt the directory.</param>
      [SecurityCritical]
      public static void Encrypt(string path, bool recursive)
      {
         EncryptDecryptDirectoryCore(path, true, recursive, PathFormat.RelativePath);
      }

      #endregion // Encrypt
      
      #region DisableEncryption

      /// <summary>[AlphaFS] Disables encryption of the specified directory and the files in it.
      ///   <para>This method only creates/modifies the file "Desktop.ini" in the root of <paramref name="path"/> and disables encryption by writing: "Disable=1"</para>
      ///   <para>This method does not affect encryption of files and subdirectories below the indicated directory.</para>
      /// </summary>
      /// <param name="path">The name of the directory for which to disable encryption.</param>
      /// <param name="pathFormat">Indicates the format of the path parameter(s).</param>
      [SecurityCritical]
      public static void DisableEncryption(string path, PathFormat pathFormat)
      {
         EnableDisableEncryptionCore(path, false, pathFormat);
      }

      /// <summary>[AlphaFS] Disables encryption of the specified directory and the files in it.
      ///   <para>This method only creates/modifies the file "Desktop.ini" in the root of <paramref name="path"/> and disables encryption by writing: "Disable=1"</para>
      ///   <para>This method does not affect encryption of files and subdirectories below the indicated directory.</para>
      /// </summary>
      /// <param name="path">The name of the directory for which to disable encryption.</param>
      [SecurityCritical]
      public static void DisableEncryption(string path)
      {
         EnableDisableEncryptionCore(path, false, PathFormat.RelativePath);
      }

      #endregion // DisableEncryption

      #region EnableEncryption

      /// <summary>[AlphaFS] Enables encryption of the specified directory and the files in it.
      ///   <para>This method only creates/modifies the file "Desktop.ini" in the root of <paramref name="path"/> and enables encryption by writing: "Disable=0"</para>
      ///   <para>This method does not affect encryption of files and subdirectories below the indicated directory.</para>
      /// </summary>
      /// <param name="path">The name of the directory for which to enable encryption.</param>
      /// <param name="pathFormat">Indicates the format of the path parameter(s).</param>
      [SecurityCritical]
      public static void EnableEncryption(string path, PathFormat pathFormat)
      {
         EnableDisableEncryptionCore(path, true, pathFormat);
      }

      /// <summary>[AlphaFS] Enables encryption of the specified directory and the files in it.
      ///   <para>This method only creates/modifies the file "Desktop.ini" in the root of <paramref name="path"/> and enables encryption by writing: "Disable=0"</para>
      ///   <para>This method does not affect encryption of files and subdirectories below the indicated directory.</para>
      /// </summary>
      /// <param name="path">The name of the directory for which to enable encryption.</param>
      [SecurityCritical]
      public static void EnableEncryption(string path)
      {
         EnableDisableEncryptionCore(path, true, PathFormat.RelativePath);
      }

      #endregion // EnableEncryption
      
      #region Internal Methods

      /// <summary>Enables/disables encryption of the specified directory and the files in it.
      ///   <para>This method only creates/modifies the file "Desktop.ini" in the root of <paramref name="path"/> and  enables/disables encryption by writing: "Disable=0" or "Disable=1".</para>
      ///   <para>This method does not affect encryption of files and subdirectories below the indicated directory.</para>
      /// </summary>
      /// <param name="path">The name of the directory for which to enable encryption.</param>
      /// <param name="enable"><see langword="true"/> enabled encryption, <see langword="false"/> disables encryption.</param>
      /// <param name="pathFormat">Indicates the format of the path parameter(s).</param>
      [SecurityCritical]
      internal static void EnableDisableEncryptionCore(string path, bool enable, PathFormat pathFormat)
      {
         if (Utils.IsNullOrWhiteSpace(path))
            throw new ArgumentNullException("path");

         string pathLp = Path.GetExtendedLengthPathCore(null, path, pathFormat, GetFullPathOptions.RemoveTrailingDirectorySeparator | GetFullPathOptions.FullCheck);

         // EncryptionDisable()
         // In the ANSI version of this function, the name is limited to 248 characters.
         // To extend this limit to 32,767 wide characters, call the Unicode version of the function and prepend "\\?\" to the path.
         // 2013-01-13: MSDN does not confirm LongPath usage but a Unicode version of this function exists.

         if (!NativeMethods.EncryptionDisable(pathLp, !enable))
            NativeError.ThrowException(pathLp);
      }

      /// <summary>Decrypts/encrypts a directory recursively so that only the account used to encrypt the directory can decrypt it.</summary>
      /// <exception cref="ArgumentException"/>
      /// <exception cref="ArgumentNullException"/>
      /// <exception cref="DirectoryNotFoundException"/>
      /// <exception cref="IOException"/>
      /// <exception cref="NotSupportedException"/>
      /// <exception cref="UnauthorizedAccessException"/>
      /// <param name="path">A path that describes a directory to encrypt.</param>
      /// <param name="encrypt"><see langword="true"/> encrypt, <see langword="false"/> decrypt.</param>
      /// <param name="recursive"><see langword="true"/> to decrypt the directory recursively. <see langword="false"/> only decrypt files and directories in the root of <paramref name="path"/>.</param>
      /// <param name="pathFormat">Indicates the format of the path parameter(s).</param>
      [SecurityCritical]
      internal static void EncryptDecryptDirectoryCore(string path, bool encrypt, bool recursive, PathFormat pathFormat)
      {
         string pathLp = Path.GetExtendedLengthPathCore(null, path, pathFormat, GetFullPathOptions.RemoveTrailingDirectorySeparator | GetFullPathOptions.FullCheck);

         var options = DirectoryEnumerationOptions.FilesAndFolders | DirectoryEnumerationOptions.AsLongPath;

         // Process folders and files when recursive. 
         if (recursive)
         {
            options |= DirectoryEnumerationOptions.Recursive;

            foreach (string fsei in EnumerateFileSystemEntryInfosCore<string>(null, pathLp, Path.WildcardStarMatchAll, options, PathFormat.LongFullPath))
               File.EncryptDecryptFileCore(true, fsei, encrypt, PathFormat.LongFullPath);
         }

         // Process the root folder, the given path.
         File.EncryptDecryptFileCore(true, pathLp, encrypt, PathFormat.LongFullPath);
      }

      #endregion // Internal Methods
   }
}