Catel - Part 4 of n: Unit testing with Catel

// --------------------------------------------------------------------------------------------------------------------
// <copyright file="Directory.cs" company="Catel development team">
//   Copyright (c) 2008 - 2011 Catel development team. All rights reserved.
// </copyright>
// <summary>
//   Directory class.
// </summary>
// --------------------------------------------------------------------------------------------------------------------

using System;
using System.Runtime.InteropServices;
using Catel.Properties;

namespace Catel.IO
{
	/// <summary>
	/// Directory class.
	/// </summary>
	public class Directory
	{
        /// <summary>
        /// Creates the specified directory.
        /// </summary>
        /// <param name="path">The path to create.</param>
		public static void CreateDirectory(string path)
		{
			System.IO.Directory.CreateDirectory(path);
		}

		/// <summary>
		/// Checks whether the specified directory exists.
		/// </summary>
		/// <param name="directory">The directory to check.</param>
		/// <returns><c>true</c> if the directory exists; otherwise <c>false</c>.</returns>
        /// <exception cref="ArgumentNullException">when <paramref name="directory"/> is <c>null</c>.</exception>
		public static bool Exists(string directory)
		{
            if (directory == null)
            {
                throw new ArgumentNullException("directory");
            }

            if (string.IsNullOrEmpty(directory))
            {
                return false;
            }

			directory = Path.AppendTrailingSlash(directory) + "*";

			return File.Exists(directory);
		}

        /// <summary>
        /// Deletes the specified directory.
        /// </summary>
        /// <param name="directory">The directory.</param>
        /// <returns><c>true</c> if the directory is deleted; otherwise <c>false</c>.</returns>
        /// <exception cref="ArgumentException">when <paramref name="directory"/> is <c>null</c> or empty.</exception>
		public static bool Delete(string directory)
		{
            if (string.IsNullOrEmpty(directory))
            {
                throw new ArgumentException(Exceptions.ArgumentCannotBeNullOrEmpty, "directory");
            }

			IntPtr invalidHandleValue = new IntPtr(-1);
			Win32IOApi.WIN32_FIND_DATA findFileData;

			directory = Path.AddWin32LongFileNamePrefix(directory);
			string originalDirectory = directory;
			directory = Path.AppendTrailingSlash(directory) + "*";

			IntPtr findHandle = Win32IOApi.FindFirstFile(directory, out findFileData);
			if (findHandle == invalidHandleValue)
			{
				return false;
			}

			bool search = true;
			while (search)
			{
				if (Win32IOApi.FindNextFile(findHandle, out findFileData))
				{
					// Is this the current or top directory, then continue
					if ((findFileData.cFileName == ".") || (findFileData.cFileName == ".."))
					{
						continue;
					}

					string fileName = Path.Combine(originalDirectory, findFileData.cFileName);

					// Is this a directory?
					if ((findFileData.dwFileAttributes & Win32IOApi.FILE_ATTRIBUTE_DIRECTORY) == Win32IOApi.FILE_ATTRIBUTE_DIRECTORY)
					{
						if (!Delete(fileName))
						{
							Win32IOApi.FindClose(findHandle);
							return false;
						}
					}
					else
					{
						// Is this a read-only file?
						if ((findFileData.dwFileAttributes & Win32IOApi.FILE_ATTRIBUTE_READONLY) == Win32IOApi.FILE_ATTRIBUTE_READONLY)
						{
							// Remove read-only flag
							Win32IOApi.SetFileAttributes(fileName, findFileData.dwFileAttributes - Win32IOApi.FILE_ATTRIBUTE_READONLY);
						}

						if (!File.Delete(fileName))
						{
							Win32IOApi.FindClose(findHandle);
							return false;
						}
					}
				}
				else
				{
					// No more files there
					if (Marshal.GetLastWin32Error() == Win32IOApi.ERROR_NO_MORE_FILES)
					{
						search = false;
					}
					else
					{
						Win32IOApi.FindClose(findHandle);
						return false;
					}
				}
			}

			Win32IOApi.FindClose(findHandle);

			return Win32IOApi.RemoveDirectory(originalDirectory);
		}
	}
}