// Copyright 1998-2015 Epic Games, Inc. All Rights Reserved.
using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Net;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Json;
using System.Text;
using System.Threading;
using Tools.DotNETCommon.XmlHandler;
using UnrealBuildTool;
using System.Runtime.CompilerServices;
using System.Linq;

namespace AutomationTool
{
	#region ParamList

	/// <summary>
	/// Wrapper around List with support for multi parameter constructor, i.e:
	///   var Maps = new ParamList<string>("Map1", "Map2");
	/// </summary>
	/// <typeparam name="T"></typeparam>
	public class ParamList<T> : List<T>
	{
		public ParamList(params T[] Args)
		{
			AddRange(Args);
		}

		public ParamList(ICollection<T> Collection)
			: base(Collection != null ? Collection : new T[] {})
		{
		}

		public override string ToString()
		{
			var Text = "";
			for (int Index = 0; Index < Count; ++Index)
			{
				if (Index > 0)
				{
					Text += ", ";
				}
				Text += this[Index].ToString();				
			}
			return Text;
		}
	}

	#endregion

	#region PathSeparator

	public enum PathSeparator
	{
		Default = 0,
		Slash,
		Backslash,
		Depot,
		Local
	}

	#endregion

	/// <summary>
	/// Base utility function for script commands.
	/// </summary>
	public partial class CommandUtils
	{
		#region Environment Setup

		static private CommandEnvironment CmdEnvironment;

		/// <summary>
		/// BuildEnvironment to use for this buildcommand. This is initialized by InitBuildEnvironment. As soon
		/// as the script execution in ExecuteBuild begins, the BuildEnv is set up and ready to use.
		/// </summary>
		static public CommandEnvironment CmdEnv
		{
			get
			{
				if (CmdEnvironment == null)
				{
					throw new AutomationException("Attempt to use CommandEnvironment before it was initialized.");
				}
				return CmdEnvironment;
			}
		}

		/// <summary>
		/// Initializes build environment. If the build command needs a specific env-var mapping or
		/// has an extended BuildEnvironment, it must implement this method accordingly.
		/// </summary>
		/// <returns>Initialized and ready to use BuildEnvironment</returns>
		static internal void InitCommandEnvironment()
		{
			CmdEnvironment = Automation.IsBuildMachine ? new CommandEnvironment() : new LocalCommandEnvironment(); ;
		}

		#endregion

		#region Logging

		/// <summary>
		/// Returns a formatted string for the specified exception (including inner exception if any).
		/// </summary>
		/// <param name="Ex"></param>
		/// <returns>Formatted exception string.</returns>
		public static string ExceptionToString(Exception Ex)
		{
			return LogUtils.FormatException(Ex);
		}

		/// <summary>
		/// Writes formatted text to log (with TraceEventType.Log).
		/// </summary>
		/// <param name="Format">Format string</param>
		/// <param name="Args">Parameters</param>
		[MethodImplAttribute(MethodImplOptions.NoInlining)]
		public static void Log(string Format, params object[] Args)
		{
			UnrealBuildTool.Log.WriteLine(1, null, TraceEventType.Information, Format, Args);
		}

		/// <summary>
		/// Writes formatted text to log (with TraceEventType.Log).
		/// </summary>
		/// <param name="Message">Text</param>
		[MethodImplAttribute(MethodImplOptions.NoInlining)]
		public static void Log(string Message)
		{
            UnrealBuildTool.Log.WriteLine(1, null, TraceEventType.Information, Message);
		}

		/// <summary>
		/// Writes formatted text to log (with TraceEventType.Error).
		/// </summary>
		/// <param name="Format">Format string</param>
		/// <param name="Args">Parameters</param>
		[MethodImplAttribute(MethodImplOptions.NoInlining)]
		public static void LogError(string Format, params object[] Args)
		{
            UnrealBuildTool.Log.WriteLine(1, null, TraceEventType.Error, Format, Args);
		}

		/// <summary>
		/// Writes formatted text to log (with TraceEventType.Error).
		/// </summary>
		/// <param name="Message">Text</param>
		[MethodImplAttribute(MethodImplOptions.NoInlining)]
		public static void LogError(string Message)
		{
            UnrealBuildTool.Log.WriteLine(1, null, TraceEventType.Error, Message);
		}

		/// <summary>
		/// Writes formatted text to log (with TraceEventType.Warning).
		/// </summary>
		/// <param name="Format">Format string</param>
		/// <param name="Args">Parameters</param>
		[MethodImplAttribute(MethodImplOptions.NoInlining)]
		public static void LogWarning(string Format, params object[] Args)
		{
            UnrealBuildTool.Log.WriteLine(1, null, TraceEventType.Warning, Format, Args);
		}

		/// <summary>
		/// Writes a message to log (with TraceEventType.Warning).
		/// </summary>
		/// <param name="Message">Text</param>
		[MethodImplAttribute(MethodImplOptions.NoInlining)]
		public static void LogWarning(string Message)
		{
            UnrealBuildTool.Log.WriteLine(1, null, TraceEventType.Warning, Message);
		}

		/// <summary>
		/// Writes formatted text to log (with TraceEventType.Verbose).
		/// </summary>
		/// <param name="Foramt">Format string</param>
		/// <param name="Args">Arguments</param>
		[MethodImplAttribute(MethodImplOptions.NoInlining)]
		public static void LogVerbose(string Format, params object[] Args)
		{
            UnrealBuildTool.Log.WriteLine(1, null, TraceEventType.Verbose, Format, Args);
		}

		/// <summary>
		/// Writes formatted text to log (with TraceEventType.Verbose).
		/// </summary>
		/// <param name="Message">Text</param>
		[MethodImplAttribute(MethodImplOptions.NoInlining)]
		public static void LogVerbose(string Message)
		{
            UnrealBuildTool.Log.WriteLine(1, null, TraceEventType.Verbose, Message);
		}

		/// <summary>
		/// Writes formatted text to log.
		/// </summary>
		/// <param name="Verbosity">Verbosity</param>
		/// <param name="Format">Format string</param>
		/// <param name="Args">Arguments</param>
		[MethodImplAttribute(MethodImplOptions.NoInlining)]
		public static void Log(TraceEventType Verbosity, string Format, params object[] Args)
		{
            UnrealBuildTool.Log.WriteLine(1, null, Verbosity, Format, Args);
		}

		/// <summary>
		/// Writes formatted text to log.
		/// </summary>
		/// <param name="Verbosity">Verbosity</param>
		/// <param name="Message">Text</param>
		[MethodImplAttribute(MethodImplOptions.NoInlining)]
		public static void Log(TraceEventType Verbosity, string Message)
		{
            UnrealBuildTool.Log.WriteLine(1, null, Verbosity, Message);
		}

		/// <summary>
		/// Dumps exception to log.
		/// </summary>
		/// <param name="Verbosity">Verbosity</param>
		/// <param name="Ex">Exception</param>
		[MethodImplAttribute(MethodImplOptions.NoInlining)]
		public static void Log(TraceEventType Verbosity, Exception Ex)
		{
            UnrealBuildTool.Log.WriteLine(1, null, Verbosity, LogUtils.FormatException(Ex));
		}

		#endregion

		#region IO

		/// <summary>
		/// Finds files in specified paths. 
		/// </summary>
		/// <param name="SearchPattern">Pattern</param>
		/// <param name="Recursive">Recursive search</param>
		/// <param name="Paths">Paths to search</param>
		/// <returns>An array of files found in the specified paths</returns>
		public static string[] FindFiles(string SearchPattern, bool Recursive, params string[] Paths)
		{
			List<string> FoundFiles = new List<string>();
			foreach (var PathToSearch in Paths)
			{
				var NormalizedPath = ConvertSeparators(PathSeparator.Default, PathToSearch);
				if (DirectoryExists(NormalizedPath))
				{
					var FoundInPath = InternalUtils.SafeFindFiles(NormalizedPath, SearchPattern, Recursive);
					if (FoundInPath == null)
					{
						throw new AutomationException(String.Format("Failed to find files in '{0}'", NormalizedPath));
					}
					FoundFiles.AddRange(FoundInPath);
				}
			}
			return FoundFiles.ToArray();
		}

		/// <summary>
		/// Finds files in specified paths. 
		/// </summary>
		/// <param name="SearchPattern">Pattern</param>
		/// <param name="Recursive">Recursive search</param>
		/// <param name="Paths">Paths to search</param>
		/// <returns>An array of files found in the specified paths</returns>
		public static string[] FindFiles_NoExceptions(string SearchPattern, bool Recursive, params string[] Paths)
		{
			List<string> FoundFiles = new List<string>();
			foreach (var PathToSearch in Paths)
			{
				var NormalizedPath = ConvertSeparators(PathSeparator.Default, PathToSearch);
				if (DirectoryExists(NormalizedPath))
				{
					var FoundInPath = InternalUtils.SafeFindFiles(NormalizedPath, SearchPattern, Recursive);
					if (FoundInPath != null)
					{
						FoundFiles.AddRange(FoundInPath);
					}
				}
			}
			return FoundFiles.ToArray();
		}
        /// <summary>
        /// Finds files in specified paths. 
        /// </summary>
        /// <param name="SearchPattern">Pattern</param>
        /// <param name="Recursive">Recursive search</param>
        /// <param name="Paths">Paths to search</param>
        /// <returns>An array of files found in the specified paths</returns>
        public static string[] FindFiles_NoExceptions(bool bQuiet, string SearchPattern, bool Recursive, params string[] Paths)
        {
            List<string> FoundFiles = new List<string>();
            foreach (var PathToSearch in Paths)
            {
                var NormalizedPath = ConvertSeparators(PathSeparator.Default, PathToSearch);
                if (DirectoryExists(NormalizedPath))
                {
                    var FoundInPath = InternalUtils.SafeFindFiles(NormalizedPath, SearchPattern, Recursive, bQuiet);
                    if (FoundInPath != null)
                    {
                        FoundFiles.AddRange(FoundInPath);
                    }
                }
            }
            return FoundFiles.ToArray();
        }
		/// <summary>
		/// Finds files in specified paths. 
		/// </summary>
		/// <param name="SearchPattern">Pattern</param>
		/// <param name="Recursive">Recursive search</param>
		/// <param name="Paths">Paths to search</param>
		/// <returns>An array of files found in the specified paths</returns>
		public static string[] FindDirectories(bool bQuiet, string SearchPattern, bool Recursive, params string[] Paths)
		{
			List<string> FoundDirs = new List<string>();
			foreach (var PathToSearch in Paths)
			{
				var NormalizedPath = ConvertSeparators(PathSeparator.Default, PathToSearch);
				if (DirectoryExists(NormalizedPath))
				{
					var FoundInPath = InternalUtils.SafeFindDirectories(NormalizedPath, SearchPattern, Recursive, bQuiet);
					if (FoundInPath == null)
					{
						throw new AutomationException(String.Format("Failed to find directories in '{0}'", NormalizedPath));
					}
					FoundDirs.AddRange(FoundInPath);
				}
			}
			return FoundDirs.ToArray();
		}
		/// <summary>
		/// Finds Directories in specified paths. 
		/// </summary>
		/// <param name="SearchPattern">Pattern</param>
		/// <param name="Recursive">Recursive search</param>
		/// <param name="Paths">Paths to search</param>
		/// <returns>An array of files found in the specified paths</returns>
		public static string[] FindDirectories_NoExceptions(bool bQuiet, string SearchPattern, bool Recursive, params string[] Paths)
		{
			List<string> FoundDirs = new List<string>();
			foreach (var PathToSearch in Paths)
			{
				var NormalizedPath = ConvertSeparators(PathSeparator.Default, PathToSearch);
				if (DirectoryExists(NormalizedPath))
				{
					var FoundInPath = InternalUtils.SafeFindDirectories(NormalizedPath, SearchPattern, Recursive, bQuiet);
					if (FoundInPath != null)
					{
						FoundDirs.AddRange(FoundInPath);
					}
				}
			}
			return FoundDirs.ToArray();
		}
		/// <summary>
		/// Deletes a file(s). 
		/// If the file does not exist, silently succeeds.
		/// If the deletion of the file fails, this function throws an Exception.
		/// </summary>
		/// <param name="Filename">Filename</param>
		public static void DeleteFile(params string[] Filenames)
		{
			foreach (var Filename in Filenames)
			{
				var NormalizedFilename = ConvertSeparators(PathSeparator.Default, Filename);
				if (!InternalUtils.SafeDeleteFile(NormalizedFilename))
				{
					throw new AutomationException(String.Format("Failed to delete file '{0}'", NormalizedFilename));
				}
			}
		}
        /// <summary>
        /// Deletes a file(s). 
        /// If the file does not exist, silently succeeds.
        /// If the deletion of the file fails, this function throws an Exception.
        /// </summary>
        /// <param name="Filename">Filename</param>
        public static void DeleteFile(bool bQuiet, params string[] Filenames)
        {
            foreach (var Filename in Filenames)
            {
                var NormalizedFilename = ConvertSeparators(PathSeparator.Default, Filename);
                if (!InternalUtils.SafeDeleteFile(NormalizedFilename, bQuiet))
                {
                    throw new AutomationException(String.Format("Failed to delete file '{0}'", NormalizedFilename));
                }
            }
        }

		/// <summary>
		/// Deletes a file(s). 
		/// If the deletion of the file fails, prints a warning.
		/// </summary>
		/// <param name="Filename">Filename</param>
        public static bool DeleteFile_NoExceptions(params string[] Filenames)
		{
			bool Result = true;
			foreach (var Filename in Filenames)
			{
				var NormalizedFilename = ConvertSeparators(PathSeparator.Default, Filename);
				if (!InternalUtils.SafeDeleteFile(NormalizedFilename))
				{
					Log(TraceEventType.Warning, "Failed to delete file '{0}'", NormalizedFilename);
					Result = false;
				}
			}
			return Result;
		}
		/// <summary>
		/// Deletes a file(s). 
		/// If the deletion of the file fails, prints a warning.
		/// </summary>
		/// <param name="Filename">Filename</param>
        /// <param name="bQuiet">if true, then don't retry and don't print much.</param>
        public static bool DeleteFile_NoExceptions(string Filename, bool bQuiet = false)
		{
			bool Result = true;
			var NormalizedFilename = ConvertSeparators(PathSeparator.Default, Filename);
			if (!InternalUtils.SafeDeleteFile(NormalizedFilename, bQuiet))
			{
				Log(bQuiet ? TraceEventType.Information : TraceEventType.Warning, "Failed to delete file '{0}'", NormalizedFilename);
				Result = false;
			}
			return Result;
		}

		/// <summary>
		/// Deletes a directory(or directories) including its contents (recursively, will delete read-only files).
		/// If the deletion of the directory fails, this function throws an Exception.
		/// </summary>
		/// <param name="bQuiet">Suppresses log output if true</param>
		/// <param name="Directory">Directory</param>
		public static void DeleteDirectory(bool bQuiet, params string[] Directories)
		{
			foreach (var Directory in Directories)
			{
				var NormalizedDirectory = ConvertSeparators(PathSeparator.Default, Directory);
				if (!InternalUtils.SafeDeleteDirectory(NormalizedDirectory, bQuiet))
				{
					throw new AutomationException(String.Format("Failed to delete directory '{0}'", NormalizedDirectory));
				}
			}
		}

		/// <summary>
		/// Deletes a directory(or directories) including its contents (recursively, will delete read-only files).
		/// If the deletion of the directory fails, this function throws an Exception.
		/// </summary>
		/// <param name="Directory">Directory</param>
		public static void DeleteDirectory(params string[] Directories)
		{
			DeleteDirectory(false, Directories);
		}

		/// <summary>
		/// Deletes a directory(or directories) including its contents (recursively, will delete read-only files).
		/// If the deletion of the directory fails, prints a warning.
		/// </summary>
		/// <param name="bQuiet">Suppresses log output if true</param>
		/// <param name="Directory">Directory</param>
		public static bool DeleteDirectory_NoExceptions(bool bQuiet, params string[] Directories)
		{
			bool Result = true;
            foreach (var Directory in Directories)
            {
                var NormalizedDirectory = ConvertSeparators(PathSeparator.Default, Directory);
                try
                {
                    if (!InternalUtils.SafeDeleteDirectory(NormalizedDirectory, bQuiet))
                    {
                        Log(TraceEventType.Warning, "Failed to delete directory '{0}'", NormalizedDirectory);
                        Result = false;
                    }
                }
                catch (Exception Ex)
                {
					if (!bQuiet)
					{
						Log(TraceEventType.Warning, "Failed to delete directory, exception '{0}'", NormalizedDirectory);
						Log(TraceEventType.Warning, Ex);
					}
                    Result = false;
                }
            }


			return Result;
		}

		/// <summary>
		/// Deletes a directory(or directories) including its contents (recursively, will delete read-only files).
		/// If the deletion of the directory fails, prints a warning.
		/// </summary>
		/// <param name="Directory">Directory</param>
		public static bool DeleteDirectory_NoExceptions(params string[] Directories)
		{
			return DeleteDirectory_NoExceptions(false, Directories);
		}


		/// <summary>
		/// Attempts to delete a directory, if that fails deletes all files and folder from the specified directory.
		/// This works around the issue when the user has a file open in a notepad from that directory. Somehow deleting the file works but
		/// deleting the directory with the file that's open, doesn't.
		/// </summary>
		/// <param name="DirectoryName"></param>
		public static void DeleteDirectoryContents(string DirectoryName)
		{
			Log("DeleteDirectoryContents({0})", DirectoryName);
			const bool bQuiet = true;
			var Files = CommandUtils.FindFiles_NoExceptions(bQuiet, "*", false, DirectoryName);
			foreach (var Filename in Files)
			{
				CommandUtils.DeleteFile_NoExceptions(Filename);
			}
			var Directories = CommandUtils.FindDirectories_NoExceptions(bQuiet, "*", false, DirectoryName);
			foreach (var SubDirectoryName in Directories)
			{
				CommandUtils.DeleteDirectory_NoExceptions(bQuiet, SubDirectoryName);
			}
		}

		/// <summary>
		/// Checks if a directory(or directories) exists.
		/// </summary>
		/// <param name="Directory">Directory</param>
		/// <returns>True if the directory exists, false otherwise.</returns>
		public static bool DirectoryExists(params string[] Directories)
		{
			bool bExists = Directories.Length > 0;
			foreach (var DirectoryName in Directories)
			{
				var NormalizedDirectory = ConvertSeparators(PathSeparator.Default, DirectoryName);
				bExists = System.IO.Directory.Exists(NormalizedDirectory) && bExists;
			}
			return bExists;
		}

		/// <summary>
		/// Checks if a directory(or directories) exists.
		/// </summary>
		/// <param name="Directory">Directory</param>
		/// <returns>True if the directory exists, false otherwise.</returns>
		public static bool DirectoryExists_NoExceptions(params string[] Directories)
		{
			bool bExists = Directories.Length > 0;
			foreach (var DirectoryName in Directories)
			{
				var NormalizedDirectory = ConvertSeparators(PathSeparator.Default, DirectoryName);
				try
				{
					bExists = System.IO.Directory.Exists(NormalizedDirectory) && bExists;
				}
				catch (Exception Ex)
				{
					Log(TraceEventType.Warning, "Unable to check if directory exists: {0}", NormalizedDirectory);
					Log(TraceEventType.Warning, Ex);
					bExists = false;
					break;
				}
			}
			return bExists;
		}

		/// <summary>
		/// Creates a directory(or directories).
		/// If the creation of the directory fails, this function throws an Exception.
		/// </summary>
		/// <param name="Directory">Directory</param>
		public static void CreateDirectory(params string[] Directories)
		{
			foreach (var DirectoryName in Directories)
			{
				var NormalizedDirectory = ConvertSeparators(PathSeparator.Default, DirectoryName);
				if (!InternalUtils.SafeCreateDirectory(NormalizedDirectory))
				{
					throw new AutomationException(String.Format("Failed to create directory '{0}'", NormalizedDirectory));
				}
			}
		}

        /// <summary>
        /// Creates a directory(or directories).
        /// If the creation of the directory fails, this function throws an Exception.
        /// </summary>
        /// <param name="Directory">Directory</param>
        public static void CreateDirectory(bool bQuiet, params string[] Directories)
        {
            foreach (var DirectoryName in Directories)
            {
                var NormalizedDirectory = ConvertSeparators(PathSeparator.Default, DirectoryName);
                if (!InternalUtils.SafeCreateDirectory(NormalizedDirectory, bQuiet))
                {
                    throw new AutomationException(String.Format("Failed to create directory '{0}'", NormalizedDirectory));
                }
            }
        }

		/// <summary>
		/// Creates a directory (or directories).
		/// If the creation of the directory fails, this function prints a warning.
		/// </summary>
		/// <param name="Directory">Directory</param>
		public static bool CreateDirectory_NoExceptions(params string[] Directories)
		{
			bool Result = true;
			foreach (var DirectoryName in Directories)
			{
				var NormalizedDirectory = ConvertSeparators(PathSeparator.Default, DirectoryName);
				if (!InternalUtils.SafeCreateDirectory(NormalizedDirectory))
				{
					Log(TraceEventType.Warning, "Failed to create directory '{0}'", NormalizedDirectory);
					Result = false;
				}
			}
			return Result;
		}

		/// <summary>
		/// Renames/moves a file.
		/// If the rename of the file fails, this function throws an Exception.
		/// </summary>
		/// <param name="OldName">Old name</param>
		/// <param name="NewName">new name</param>
        public static void RenameFile(string OldName, string NewName, bool bQuiet = false)
		{
			var OldNormalized = ConvertSeparators(PathSeparator.Default, OldName);
			var NewNormalized = ConvertSeparators(PathSeparator.Default, NewName);
			if (!InternalUtils.SafeRenameFile(OldNormalized, NewNormalized, bQuiet))
			{
				throw new AutomationException(String.Format("Failed to rename/move file '{0}' to '{1}'", OldNormalized, NewNormalized));
			}
		}

		/// <summary>
		/// Renames/moves a file.
		/// If the rename of the file fails, this function prints a warning.
		/// </summary>
		/// <param name="OldName">Old name</param>
		/// <param name="NewName">new name</param>
		public static bool RenameFile_NoExceptions(string OldName, string NewName)
		{
			var OldNormalized = ConvertSeparators(PathSeparator.Default, OldName);
			var NewNormalized = ConvertSeparators(PathSeparator.Default, NewName);
			var Result = InternalUtils.SafeRenameFile(OldNormalized, NewNormalized);
			if (!Result)
			{
				Log(TraceEventType.Warning, "Failed to rename/move file '{0}' to '{1}'", OldName, NewName);
			}
			return Result;
		}

		/// <summary>
		/// Checks if a file(s) exists.
		/// </summary>
		/// <param name="Filename">Filename.</param>
		/// <returns>True if the file exists, false otherwise.</returns>
		public static bool FileExists(params string[] Filenames)
		{
			bool bExists = Filenames.Length > 0;
			foreach (var Filename in Filenames)
			{
				var NormalizedFilename = ConvertSeparators(PathSeparator.Default, Filename);
				bExists = InternalUtils.SafeFileExists(NormalizedFilename) && bExists;
			}
			return bExists;
		}

		/// <summary>
		/// Checks if a file(s) exists.
		/// </summary>
		/// <param name="Filename">Filename.</param>
		/// <returns>True if the file exists, false otherwise.</returns>
		public static bool FileExists_NoExceptions(params string[] Filenames)
		{
			// Standard version doesn't throw, but keep this function for consistency.
			return FileExists(Filenames);
		}
        /// <summary>
        /// Checks if a file(s) exists.
        /// </summary>
        /// <param name="Filename">Filename.</param>
        /// <returns>True if the file exists, false otherwise.</returns>
        public static bool FileExists(bool bQuiet, params string[] Filenames)
        {
            bool bExists = Filenames.Length > 0;
            foreach (var Filename in Filenames)
            {
                var NormalizedFilename = ConvertSeparators(PathSeparator.Default, Filename);
                bExists = InternalUtils.SafeFileExists(NormalizedFilename, bQuiet) && bExists;
            }
            return bExists;
        }

        /// <summary>
        /// Checks if a file(s) exists.
        /// </summary>
        /// <param name="Filename">Filename.</param>
        /// <returns>True if the file exists, false otherwise.</returns>
        public static bool FileExists_NoExceptions(bool bQuiet, params string[] Filenames)
        {
            // Standard version doesn't throw, but keep this function for consistency.
            return FileExists(bQuiet, Filenames);
        }

		static Stack<string> WorkingDirectoryStack = new Stack<string>();

		/// <summary>
		/// Pushes the current working directory onto a stack and sets CWD to a new value.
		/// </summary>
		/// <param name="WorkingDirectory">New working direcotry.</param>
		public static void PushDir(string WorkingDirectory)
		{
			string OrigCurrentDirectory = Environment.CurrentDirectory;
			WorkingDirectory = ConvertSeparators(PathSeparator.Default, WorkingDirectory);
			try
			{
				Environment.CurrentDirectory = WorkingDirectory;
			}
			catch (Exception Ex)
			{
				throw new AutomationException(String.Format("Unable to change current directory to {0}", WorkingDirectory), Ex);
			}

			WorkingDirectoryStack.Push(OrigCurrentDirectory);
		}

		/// <summary>
		/// Pushes the current working directory onto a stack and sets CWD to a new value.
		/// </summary>
		/// <param name="WorkingDirectory">New working direcotry.</param>
		public static bool PushDir_NoExceptions(string WorkingDirectory)
		{
			bool Result = true;
			string OrigCurrentDirectory = Environment.CurrentDirectory;
			WorkingDirectory = ConvertSeparators(PathSeparator.Default, WorkingDirectory);
			try
			{
				Environment.CurrentDirectory = WorkingDirectory;
				WorkingDirectoryStack.Push(OrigCurrentDirectory);
			}
			catch
			{
				Log(TraceEventType.Warning, "Unable to change current directory to {0}", WorkingDirectory);
				Result = false;
			}
			return Result;
		}

		/// <summary>
		/// Pops the last working directory from a stack and sets it as the current working directory.
		/// </summary>
		public static void PopDir()
		{
			if (WorkingDirectoryStack.Count > 0)
			{
				Environment.CurrentDirectory = WorkingDirectoryStack.Pop();
			}
			else
			{
				throw new AutomationException("Unable to PopDir. WorkingDirectoryStack is empty.");
			}
		}

		/// <summary>
		/// Pops the last working directory from a stack and sets it as the current working directory.
		/// </summary>
		public static bool PopDir_NoExceptions()
		{
			bool Result = true;
			if (WorkingDirectoryStack.Count > 0)
			{
				Environment.CurrentDirectory = WorkingDirectoryStack.Pop();
			}
			else
			{
				Log(TraceEventType.Warning, "Unable to PopDir. WorkingDirectoryStack is empty.");
				Result = false;
			}
			return Result;
		}

		/// <summary>
		/// Clears the directory stack
		/// </summary>
		public static void ClearDirStack()
		{
			while (WorkingDirectoryStack.Count > 0)
			{
				PopDir();
			}
		}

		/// <summary>
		/// Changes the current working directory.
		/// </summary>
		/// <param name="WorkingDirectory">New working directory.</param>
		public static void ChDir(string WorkingDirectory)
		{
			WorkingDirectory = ConvertSeparators(PathSeparator.Default, WorkingDirectory);
			try
			{
				Environment.CurrentDirectory = WorkingDirectory;
			}
			catch (Exception Ex)
			{
				throw new ArgumentException(String.Format("Unable to change current directory to {0}", WorkingDirectory), Ex);
			}
		}

		/// <summary>
		/// Changes the current working directory.
		/// </summary>
		/// <param name="WorkingDirectory">New working directory.</param>
		public static bool ChDir_NoExceptions(string WorkingDirectory)
		{
			bool Result = true;
			WorkingDirectory = ConvertSeparators(PathSeparator.Default, WorkingDirectory);
			try
			{
				Environment.CurrentDirectory = WorkingDirectory;
			}
			catch
			{
				Log(TraceEventType.Warning, "Unable to change current directory to {0}", WorkingDirectory);
				Result = false;
			}
			return Result;
		}

		/// <summary>
		/// Sets file attributes. Will not change attributes that have not been specified.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <param name="ReadOnly">Read-only attribute</param>
		/// <param name="Hidden">Hidden attribute.</param>
		/// <param name="Archive">Archive attribute.</param>
		public static void SetFileAttributes(string Filename, bool? ReadOnly = null, bool? Hidden = null, bool? Archive = null)
		{
			Filename = ConvertSeparators(PathSeparator.Default, Filename);
			if (!File.Exists(Filename))
			{
				throw new AutomationException("Unable to set attributes for a non-exisiting file.", new FileNotFoundException("File not found.", Filename));
			}

			FileAttributes Attributes = File.GetAttributes(Filename);
			Attributes = InternalSetAttributes(ReadOnly, Hidden, Archive, Attributes);
			File.SetAttributes(Filename, Attributes);
		}

		/// <summary>
		/// Sets file attributes. Will not change attributes that have not been specified.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <param name="ReadOnly">Read-only attribute</param>
		/// <param name="Hidden">Hidden attribute.</param>
		/// <param name="Archive">Archive attribute.</param>
		public static bool SetFileAttributes_NoExceptions(string Filename, bool? ReadOnly = null, bool? Hidden = null, bool? Archive = null)
		{			
			Filename = ConvertSeparators(PathSeparator.Default, Filename);
			if (!File.Exists(Filename))
			{
				Log(TraceEventType.Warning, "Unable to set attributes for a non-exisiting file ({0})", Filename);
				return false;
			}

			bool Result = true;
			try
			{
				FileAttributes Attributes = File.GetAttributes(Filename);
				Attributes = InternalSetAttributes(ReadOnly, Hidden, Archive, Attributes);
				File.SetAttributes(Filename, Attributes);
			}
			catch (Exception Ex)
			{
				Log(TraceEventType.Warning, "Error trying to set file attributes for: {0}", Filename);
				Log(TraceEventType.Warning, Ex);
				Result = false;
			}
			return Result;
		}

		private static FileAttributes InternalSetAttributes(bool? ReadOnly, bool? Hidden, bool? Archive, FileAttributes Attributes)
		{
			if (ReadOnly != null)
			{
				if ((bool)ReadOnly)
				{
					Attributes |= FileAttributes.ReadOnly;
				}
				else
				{
					Attributes &= ~FileAttributes.ReadOnly;
				}
			}
			if (Hidden != null)
			{
				if ((bool)Hidden)
				{
					Attributes |= FileAttributes.Hidden;
				}
				else
				{
					Attributes &= ~FileAttributes.Hidden;
				}
			}
			if (Archive != null)
			{
				if ((bool)Archive)
				{
					Attributes |= FileAttributes.Archive;
				}
				else
				{
					Attributes &= ~FileAttributes.Archive;
				}
			}
			return Attributes;
		}

		/// <summary>
		/// Writes a line of formatted string to a file. Creates the file if it does not exists.
		/// If the file does exists, appends a new line.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <param name="Format">Format string</param>
		/// <param name="Args">Arguments</param>
		public static void WriteToFile(string Filename, string Format, params object[] Args)
		{
			WriteToFile(Filename, String.Format(Format, Args));
		}

		/// <summary>
		/// Writes a line of formatted string to a file. Creates the file if it does not exists.
		/// If the file does exists, appends a new line.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <param name="Text">Text to write</param>
		public static void WriteToFile(string Filename, string Text)
		{
			try
			{
				Filename = ConvertSeparators(PathSeparator.Default, Filename);
				FileStream Stream;
				if (File.Exists(Filename))
				{
					Stream = new FileStream(Filename, FileMode.Append, FileAccess.Write, FileShare.Read);
				}
				else
				{
					Stream = new FileStream(Filename, FileMode.OpenOrCreate, FileAccess.Write, FileShare.Read);
				}
				if (Stream != null)
				{
					using (StreamWriter Writer = new StreamWriter(Stream))
					{
						Writer.WriteLine(Text);
						Writer.Flush();
						Writer.Close();
					}
					Stream.Dispose();
				}
			}
			catch (Exception Ex)
			{
				throw new AutomationException(String.Format("Failed to Write to file {0}", Filename), Ex);
			}
		}

		/// <summary>
		/// Reads all text lines from a file.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <returns>Array of lines of text read from the file. null if the file did not exist or could not be read.</returns>
		public static string[] ReadAllLines(string Filename)
		{
			Filename = ConvertSeparators(PathSeparator.Default, Filename);
			return InternalUtils.SafeReadAllLines(Filename);
		}

		/// <summary>
		/// Reads all text from a file.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <returns>All text read from the file. null if the file did not exist or could not be read.</returns>
		public static string ReadAllText(string Filename)
		{
			Filename = ConvertSeparators(PathSeparator.Default, Filename);
			return InternalUtils.SafeReadAllText(Filename);
		}

		/// <summary>
		/// Writes lines to a file.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <param name="Lines">Text</param>
		public static void WriteAllLines(string Filename, string[] Lines)
		{
			Filename = ConvertSeparators(PathSeparator.Default, Filename);
			if (!InternalUtils.SafeWriteAllLines(Filename, Lines))
			{
				throw new AutomationException("Unable to write to file: {0}", Filename);
			}
		}

		/// <summary>
		/// Writes lines to a file.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <param name="Lines">Text</param>
		public static bool WriteAllLines_NoExceptions(string Filename, string[] Lines)
		{
			Filename = ConvertSeparators(PathSeparator.Default, Filename);
			return InternalUtils.SafeWriteAllLines(Filename, Lines);
		}

		/// <summary>
		/// Writes text to a file.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <param name="Lines">Text</param>
		public static void WriteAllText(string Filename, string Text)
		{
			Filename = ConvertSeparators(PathSeparator.Default, Filename);
			if (!InternalUtils.SafeWriteAllText(Filename, Text))
			{
				throw new AutomationException("Unable to write to file: {0}", Filename);
			}
		}

		/// <summary>
		/// Writes text to a file.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <param name="Lines">Text</param>
		public static bool WriteAllText_NoExceptions(string Filename, string Text)
		{
			Filename = ConvertSeparators(PathSeparator.Default, Filename);
			return InternalUtils.SafeWriteAllText(Filename, Text);
		}


		/// <summary>
		/// Writes byte array to a file.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <param name="Bytes">Byte array</param>
		public static void WriteAllBytes(string Filename, byte[] Bytes)
		{
			Filename = ConvertSeparators(PathSeparator.Default, Filename);
			if (!InternalUtils.SafeWriteAllBytes(Filename, Bytes))
			{
				throw new AutomationException("Unable to write to file: {0}", Filename);
			}
		}

		/// <summary>
		/// Writes byte array to a file.
		/// </summary>
		/// <param name="Filename">Filename</param>
		/// <param name="Bytes">Byte array</param>
		public static bool WriteAllBytes_NoExceptions(string Filename, byte[] Bytes)
		{
			Filename = ConvertSeparators(PathSeparator.Default, Filename);
			return InternalUtils.SafeWriteAllBytes(Filename, Bytes);
		}

		/// <summary>
		/// Gets a character representing the specified separator type.
		/// </summary>
		/// <param name="SeparatorType">Separator type.</param>
		/// <returns>Separator character</returns>
		public static char GetPathSeparatorChar(PathSeparator SeparatorType)
		{
			char Separator;
			switch (SeparatorType)
			{
				case PathSeparator.Slash:
				case PathSeparator.Depot:
					Separator = '/';
					break;
				case PathSeparator.Backslash:
					Separator = '\\';
					break;
				default:
					Separator = Path.DirectorySeparatorChar;
					break;
			}
			return Separator;
		}

		/// <summary>
		/// Checks if the character is one of the two sperator types ('\' or '/')
		/// </summary>
		/// <param name="Character">Character to check.</param>
		/// <returns>True if the character is a separator, false otherwise.</returns>
		public static bool IsPathSeparator(char Character)
		{
			return (Character == '/' || Character == '\\');
		}

		/// <summary>
		/// Combines paths and replaces all path separators with the system default separator.
		/// </summary>
		/// <param name="Paths"></param>
		/// <returns>Combined Path</returns>
		public static string CombinePaths(params string[] Paths)
		{
			return CombinePaths(PathSeparator.Default, Paths);
		}

		/// <summary>
		/// Combines paths and replaces all path separators wth the system specified separator.
		/// </summary>
		/// <param name="SeparatorType">Type of separartor to use when combining paths.</param>
		/// <param name="Paths"></param>
		/// <returns>Combined Path</returns>
		public static string CombinePaths(PathSeparator SeparatorType, params string[] Paths)
		{
			// Pick a separator to use.
			var SeparatorToUse = GetPathSeparatorChar(SeparatorType);
			var SeparatorToReplace = SeparatorToUse == '/' ? '\\' : '/';

			// Allocate string builder
			int CombinePathMaxLength = 0;
			foreach (var PathPart in Paths)
			{
				CombinePathMaxLength += (PathPart != null) ? PathPart.Length : 0;
			}
			CombinePathMaxLength += Paths.Length;
			var CombinedPath = new StringBuilder(CombinePathMaxLength);

			// Combine all paths
			CombinedPath.Append(Paths[0]);
			for (int PathIndex = 1; PathIndex < Paths.Length; ++PathIndex)
			{
				var NextPath = Paths[PathIndex];
				if (String.IsNullOrEmpty(NextPath) == false)
				{
					int NextPathStartIndex = 0;
					if (CombinedPath.Length != 0)
					{
						var LastChar = CombinedPath[CombinedPath.Length - 1];
						var NextChar = NextPath[0];
						var IsLastCharPathSeparator = IsPathSeparator(LastChar);
						var IsNextCharPathSeparator = IsPathSeparator(NextChar);
						// Check if a separator between paths is required
						if (!IsLastCharPathSeparator && !IsNextCharPathSeparator)
						{
							CombinedPath.Append(SeparatorToUse);
						}
						// Check if one of the saprators needs to be skipped.
						else if (IsLastCharPathSeparator && IsNextCharPathSeparator)
						{
							NextPathStartIndex = 1;
						}
					}
					CombinedPath.Append(NextPath, NextPathStartIndex, NextPath.Length - NextPathStartIndex);
				}
			}
			// Make sure there's only one separator type used.
			CombinedPath.Replace(SeparatorToReplace, SeparatorToUse);
			return CombinedPath.ToString();
		}

		/// <summary>
		/// Converts all separators in path to the specified separator type.
		/// </summary>
		/// <param name="ToSperatorType">Desired separator type.</param>
		/// <param name="PathToConvert">Path</param>
		/// <returns>Path where all separators have been converted to the specified type.</returns>
		public static string ConvertSeparators(PathSeparator ToSperatorType, string PathToConvert)
		{
			return CombinePaths(ToSperatorType, PathToConvert);
		}

		/// <summary>
		/// Copies a file.
		/// </summary>
		/// <param name="Source"></param>
		/// <param name="Dest"></param>
		/// <returns>True if the operation was successful, false otherwise.</returns>
        public static void CopyFile(string Source, string Dest, bool bQuiet = false)
		{
			Source = ConvertSeparators(PathSeparator.Default, Source);
			Dest = ConvertSeparators(PathSeparator.Default, Dest);
			if (InternalUtils.SafeFileExists(Dest, true))
			{
				InternalUtils.SafeDeleteFile(Dest, bQuiet);
			}
			else if (!InternalUtils.SafeDirectoryExists(Path.GetDirectoryName(Dest), true))
			{
				if (!InternalUtils.SafeCreateDirectory(Path.GetDirectoryName(Dest), bQuiet))
				{
					throw new AutomationException("Failed to create directory {0} for copy", Path.GetDirectoryName(Dest));
				}
			}
			if (InternalUtils.SafeFileExists(Dest, true))
			{
				throw new AutomationException("Failed to delete {0} for copy", Dest);
			}
			if (!InternalUtils.SafeCopyFile(Source, Dest, bQuiet))
			{
				throw new AutomationException("Failed to copy {0} to {1}", Source, Dest);
			}
		}

		/// <summary>
		/// Copies a file. Does not throw exceptions.
		/// </summary>
		/// <param name="Source"></param>
		/// <param name="Dest"></param>
		/// <returns>True if the operation was successful, false otherwise.</returns>
        public static bool CopyFile_NoExceptions(string Source, string Dest, bool bQuiet = false)
		{
			Source = ConvertSeparators(PathSeparator.Default, Source);
			Dest = ConvertSeparators(PathSeparator.Default, Dest);
            if (InternalUtils.SafeFileExists(Dest, true))
			{
                InternalUtils.SafeDeleteFile(Dest, bQuiet);
			}
			else if (!InternalUtils.SafeDirectoryExists(Path.GetDirectoryName(Dest), true))
			{
				if (!InternalUtils.SafeCreateDirectory(Path.GetDirectoryName(Dest)))
				{
					return false;
				}
			}
			if (InternalUtils.SafeFileExists(Dest, true))
			{
				return false;
			}
			return InternalUtils.SafeCopyFile(Source, Dest, bQuiet);
		}

		/// <summary>
		/// Copies a file if the dest doesn't exist or (optionally) if the dest timestamp is different; after a copy, copies the timestamp
		/// </summary>
		/// <param name="Source">The full path to the source file</param>
		/// <param name="Dest">The full path to the destination file</param>
		/// <param name="bAllowDifferingTimestamps">If true, will always skip a file if the destination exists, even if timestamp differs; defaults to false</param>
		/// <returns>True if the operation was successful, false otherwise.</returns>
		public static void CopyFileIncremental(string Source, string Dest, bool bAllowDifferingTimestamps = false, bool bFilterSpecialLinesFromIniFiles = false)
		{
			Source = ConvertSeparators(PathSeparator.Default, Source);
			Dest = ConvertSeparators(PathSeparator.Default, Dest);
			if (InternalUtils.SafeFileExists(Dest, true))
			{
				if (bAllowDifferingTimestamps == true)
				{
					Log("CopyFileIncremental Skipping {0}, already exists", Dest);
					return;
				}
				TimeSpan Diff = File.GetLastWriteTimeUtc(Dest) - File.GetLastWriteTimeUtc(Source);
				if (Diff.TotalSeconds > -1 && Diff.TotalSeconds < 1)
				{
					Log("CopyFileIncremental Skipping {0}, up to date.", Dest);
					return;
				}
				InternalUtils.SafeDeleteFile(Dest);
			}
			else if (!InternalUtils.SafeDirectoryExists(Path.GetDirectoryName(Dest), true))
			{
				if (!InternalUtils.SafeCreateDirectory(Path.GetDirectoryName(Dest)))
				{
					throw new AutomationException("Failed to create directory {0} for copy", Path.GetDirectoryName(Dest));
				}
			}
			if (InternalUtils.SafeFileExists(Dest, true))
			{
				throw new AutomationException("Failed to delete {0} for copy", Dest);
			}
			if (!InternalUtils.SafeCopyFile(Source, Dest, bFilterSpecialLinesFromIniFiles:bFilterSpecialLinesFromIniFiles))
			{
				throw new AutomationException("Failed to copy {0} to {1}", Source, Dest);
			}
			FileAttributes Attributes = File.GetAttributes(Dest);
			if ((Attributes & FileAttributes.ReadOnly) != 0)
			{
				File.SetAttributes(Dest, Attributes & ~FileAttributes.ReadOnly);
			}
			File.SetLastWriteTimeUtc(Dest, File.GetLastWriteTimeUtc(Source));
		}

		/// <summary>
		/// Copies a directory and all of it's contents recursively. Does not throw exceptions.
		/// </summary>
		/// <param name="Source"></param>
		/// <param name="Dest"></param>
		/// <returns>True if the operation was successful, false otherwise.</returns>
		public static bool CopyDirectory_NoExceptions(string Source, string Dest, bool bQuiet = false)
		{
			Source = ConvertSeparators(PathSeparator.Default, Source);
			Dest = ConvertSeparators(PathSeparator.Default, Dest);
			Dest.TrimEnd(PathSeparator.Default.ToString().ToCharArray());

			if (InternalUtils.SafeDirectoryExists(Dest))
			{
				InternalUtils.SafeDeleteDirectory(Dest, bQuiet);
				if (InternalUtils.SafeDirectoryExists(Dest, true))
				{
					return false;
				}
			}

			if (!InternalUtils.SafeCreateDirectory(Dest, bQuiet))
			{
				return false;
			}
			foreach (var SourceSubDirectory in Directory.GetDirectories(Source))
			{
				string DestPath = Dest + GetPathSeparatorChar(PathSeparator.Default) + GetLastDirectoryName(SourceSubDirectory);
				if (!CopyDirectory_NoExceptions(SourceSubDirectory, DestPath, bQuiet))
				{
					return false;
				}
			}
			foreach (var SourceFile in Directory.GetFiles(Source))
			{
				int FilenameStart = SourceFile.LastIndexOf(GetPathSeparatorChar(PathSeparator.Default));
				string DestPath = Dest + SourceFile.Substring(FilenameStart);
				if (!CopyFile_NoExceptions(SourceFile, DestPath, bQuiet))
				{
					return false;
				}
			}

			return true;
		}

		/// <summary>
		/// Returns directory name without filename. 
		/// The difference between this and Path.GetDirectoryName is that this
		/// function will not throw away the last name if it doesn't have an extension, for example:
		/// D:\Project\Data\Asset -> D:\Project\Data\Asset
		/// D:\Project\Data\Asset.ussset -> D:\Project\Data
		/// </summary>
		/// <param name="FilePath"></param>
		/// <returns></returns>
		public static string GetDirectoryName(string FilePath)
		{
			var LastSeparatorIndex = Math.Max(FilePath.LastIndexOf('/'), FilePath.LastIndexOf('\\'));
			var ExtensionIndex = FilePath.LastIndexOf('.');
			if (ExtensionIndex > LastSeparatorIndex || LastSeparatorIndex == (FilePath.Length - 1))
			{
				return FilePath.Substring(0, LastSeparatorIndex);
			}
			else
			{
				return FilePath;
			}
		}

		/// <summary>
		/// Returns the last directory name in the path string.
		/// For example: D:\Temp\Project\File.txt -> Project, Data\Samples -> Samples
		/// </summary>
		/// <param name="FilePath"></param>
		/// <returns></returns>
		public static string GetLastDirectoryName(string FilePath)
		{
			var LastDir = GetDirectoryName(FilePath);
			var LastSeparatorIndex = Math.Max(LastDir.LastIndexOf('/'), LastDir.LastIndexOf('\\'));
			if (LastSeparatorIndex >= 0)
			{
				LastDir = LastDir.Substring(LastSeparatorIndex + 1);
			}
			return LastDir;
		}

		/// <summary>
		/// Removes multi-dot extensions from a filename (i.e. *.automation.csproj)
		/// </summary>
		/// <param name="Filename">Filename to remove the extensions from</param>
		/// <returns>Clean filename.</returns>
		public static string GetFilenameWithoutAnyExtensions(string Filename)
		{
			do
			{
				Filename = Path.GetFileNameWithoutExtension(Filename);
			}
			while (Filename.IndexOf('.') >= 0);
			return Filename;
		}

		/// <summary>
		/// Reads a file manifest and returns it
		/// </summary>
		/// <param name="ManifestName">ManifestName</param>
		/// <returns></returns>
		public static UnrealBuildTool.BuildManifest ReadManifest(string ManifestName)
		{
			return XmlHandler.ReadXml<UnrealBuildTool.BuildManifest>(ManifestName);
		}

		private static void CloneDirectoryRecursiveWorker(string SourcePathBase, string TargetPathBase, List<string> ClonedFiles)
		{
            if (!InternalUtils.SafeCreateDirectory(TargetPathBase))
            {
                throw new AutomationException("Failed to create directory {0} for copy", TargetPathBase);
            }

			DirectoryInfo SourceDirectory = new DirectoryInfo(SourcePathBase);
			DirectoryInfo[] SourceSubdirectories = SourceDirectory.GetDirectories();

			// Copy the files
			FileInfo[] SourceFiles = SourceDirectory.GetFiles();
			foreach (FileInfo SourceFI in SourceFiles)
			{
				string TargetFilename = CommandUtils.CombinePaths(TargetPathBase, SourceFI.Name);
				SourceFI.CopyTo(TargetFilename);

				if (ClonedFiles != null)
				{
					ClonedFiles.Add(TargetFilename);
				}
			}

			// Recurse into subfolders
			foreach (DirectoryInfo SourceSubdir in SourceSubdirectories)
			{
				string NewSourcePath = CommandUtils.CombinePaths(SourcePathBase, SourceSubdir.Name);
				string NewTargetPath = CommandUtils.CombinePaths(TargetPathBase, SourceSubdir.Name);
				CloneDirectoryRecursiveWorker(NewSourcePath, NewTargetPath, ClonedFiles);
			}
		}

		/// <summary>
		/// Clones a directory.
		/// Warning: Will delete all of the existing files in TargetPath
		/// This is recursive, copying subfolders too.
		/// </summary>
		/// <param name="SourcePath">Source directory.</param>
		/// <param name="TargetPath">Target directory.</param>
		/// <param name="ClonedFiles">List of cloned files.</param>
		public static void CloneDirectory(string SourcePath, string TargetPath, List<string> ClonedFiles = null)
		{
			DeleteDirectory_NoExceptions(TargetPath);

			CloneDirectoryRecursiveWorker(SourcePath, TargetPath, ClonedFiles);
		}

		#endregion

		#region Threaded Copy

		/// <summary>
		/// Single batch of files to copy on a thread
		/// </summary>
		class CopyRequest
		{
			public string[] Source;
			public string[] Dest;
			public Exception Result;
			public Thread Worker;
		}

		/// <summary>
		/// Main thread procedure for copying files
		/// </summary>
		private static void CopyThreadProc(object Request)
		{
			const bool bQuiet = true;
			var FileToCopy = (CopyRequest)Request;
			try
			{
				for (int Index = 0; Index < FileToCopy.Source.Length; ++Index)
				{
					CopyFile(FileToCopy.Source[Index], FileToCopy.Dest[Index], bQuiet);
				}
			}
			catch (Exception Ex)
			{
				FileToCopy.Result = Ex;
			}
		}

		/// <summary>
		/// Copies files using miltiple threads
		/// </summary>
		/// <param name="SourceDirectory"></param>
		/// <param name="DestDirectory"></param>
		/// <param name="MaxThreads"></param>
		public static void ThreadedCopyFiles(string SourceDirectory, string DestDirectory, int MaxThreads = 64)
		{
			CreateDirectory(DestDirectory);

			var SourceFiles = Directory.GetFiles(SourceDirectory, "*", SearchOption.AllDirectories);
			var SourceBase = GetDirectoryName(SourceDirectory) + GetPathSeparatorChar(PathSeparator.Default);
			var DestBase = GetDirectoryName(DestDirectory) + GetPathSeparatorChar(PathSeparator.Default);
			var DestFiles = new string[SourceFiles.Length];
			for (int Index = 0; Index < SourceFiles.Length; ++Index)
			{
				DestFiles[Index] = SourceFiles[Index].Replace(SourceBase, DestBase);
			}
			ThreadedCopyFiles(SourceFiles, DestFiles, MaxThreads);
		}

		/// <summary>
		/// Copies files using multiple threads
		/// </summary>
		/// <param name="SourceDirectory"></param>
		/// <param name="DestDirectory"></param>
		/// <param name="MaxThreads"></param>
		public static void ThreadedCopyFiles(string[] Source, string[] Dest, int MaxThreads = 64)
		{
			Log("Copying {0} file(s) using max {1} thread(s)", Source.Length, MaxThreads);

			if (Source.Length != Dest.Length)
			{
				throw new AutomationException("Source count ({0}) does not match Dest count ({1})", Source.Length, Dest.Length);
			}
			const int MinFilesPerThread = 10;
			if (MaxThreads > 1 && Source.Length > MinFilesPerThread)
			{
				// Split evenly across the threads
				int FilesPerThread = Math.Max(Source.Length / MaxThreads, MinFilesPerThread);
				int ThreadCount = Math.Min(Source.Length / FilesPerThread + 1, MaxThreads);
				FilesPerThread = Source.Length / ThreadCount + 1;

				// Divide and copy
				var WorkerThreads = new List<CopyRequest>(ThreadCount);
				var FilesToCopy = Source.Length;
				var FirstFileIndex = 0;
				while (FilesToCopy > 0)
				{
					var Request = new CopyRequest();
					WorkerThreads.Add(Request);

					Request.Source = new string[Math.Min(FilesToCopy, FilesPerThread)];
					Request.Dest = new string[Request.Source.Length];
					Array.Copy(Source, FirstFileIndex, Request.Source, 0, Request.Source.Length);
					Array.Copy(Dest, FirstFileIndex, Request.Dest, 0, Request.Dest.Length);

					Request.Worker = new Thread(new ParameterizedThreadStart(CopyThreadProc));
					Request.Worker.Start(Request);

					FirstFileIndex += Request.Source.Length;
					FilesToCopy -= Request.Source.Length;
				}

				// Wait for completion
				foreach (var Request in WorkerThreads)
				{
					if (Request.Worker.IsAlive)
					{
						Request.Worker.Join();
					}
					if (Request.Result != null)
					{
						throw new AutomationException(String.Format("Failed to thread-copy files: {0}", Request.Result.Message), Request.Result);
					}
				}
			}
			else
			{
				const bool bQuiet = true;
				for (int Index = 0; Index < Source.Length; ++Index)
				{
					CopyFile(Source[Index], Dest[Index], bQuiet);
				}
			}
		}

		/// <summary>
		/// Copies a set of files from one folder to another
		/// </summary>
		/// <param name="SourceDir">Source directory</param>
		/// <param name="TargetDir">Target directory</param>
		/// <param name="RelativePaths">Paths relative to the source directory to copy</param>
		/// <param name="bIgnoreSymlinks">Whether to ignore symlinks during the copy</param>
		/// <param name="MaxThreads">Maximum number of threads to create</param>
		/// <returns>Array of filenames copied to the target directory</returns>
		public static string[] ThreadedCopyFiles(string SourceDir, string TargetDir, string[] RelativePaths, int MaxThreads = 64)
		{
			string[] SourceFileNames = new string[RelativePaths.Length];
			string[] TargetFileNames = new string[RelativePaths.Length];
			for(int Idx = 0; Idx < RelativePaths.Length; Idx++)
			{
				SourceFileNames[Idx] = CommandUtils.CombinePaths(SourceDir, RelativePaths[Idx]);
				TargetFileNames[Idx] = CommandUtils.CombinePaths(TargetDir, RelativePaths[Idx]);
			}
			CommandUtils.ThreadedCopyFiles(SourceFileNames, TargetFileNames, MaxThreads);
			return TargetFileNames;
		}

		/// <summary>
		/// Copies a set of files from one folder to another
		/// </summary>
		/// <param name="SourceDir">Source directory</param>
		/// <param name="TargetDir">Target directory</param>
		/// <param name="Filter">Filter which selects files from the source directory to copy</param>
		/// <param name="bIgnoreSymlinks">Whether to ignore symlinks during the copy</param>
		/// <param name="MaxThreads">Maximum number of threads to create</param>
		/// <returns>Array of filenames copied to the target directory</returns>
		public static string[] ThreadedCopyFiles(string SourceDir, string TargetDir, FileFilter Filter, bool bIgnoreSymlinks, int MaxThreads = 64)
		{
			// Filter all the relative paths
			CommandUtils.Log("Applying filter to {0}...", SourceDir);
			string[] RelativePaths = Filter.ApplyToDirectory(SourceDir, bIgnoreSymlinks).ToArray();
			return ThreadedCopyFiles(SourceDir, TargetDir, RelativePaths);
		}

		#endregion

		#region Environment variables

		/// <summary>
		/// Gets environment variable value.
		/// </summary>
		/// <param name="Name">Name of the environment variable</param>
		/// <returns>Environment variable value as string.</returns>
		public static string GetEnvVar(string Name)
		{
			return InternalUtils.GetEnvironmentVariable(Name, "");
		}

		/// <summary>
		/// Gets environment variable value.
		/// </summary>
		/// <param name="Name">Name of the environment variable</param>
		/// <param name="DefaultValue">Default value of the environment variable if the variable is not set.</param>
		/// <returns>Environment variable value as string.</returns>
		public static string GetEnvVar(string Name, string DefaultValue)
		{
			return InternalUtils.GetEnvironmentVariable(Name, DefaultValue);
		}

		/// <summary>
		/// Sets environment variable.
		/// </summary>
		/// <param name="Name">Variable name.</param>
		/// <param name="Value">Variable value.</param>
		/// <returns>True if the value has been set, false otherwise.</returns>
		public static void SetEnvVar(string Name, object Value)
		{
			try
			{
				Log("SetEnvVar {0}={1}", Name, Value);
				Environment.SetEnvironmentVariable(Name, Value.ToString());
			}
			catch (Exception Ex)
			{
				throw new AutomationException(String.Format("Failed to set environment variable {0} to {1}", Name, Value), Ex);
			}
		}

		/// <summary>
		/// Sets the environment variable if it hasn't been already.
		/// </summary>
		/// <param name="VarName">Environment variable name</param>
		/// <param name="Value">New value</param>
		public static void ConditionallySetEnvVar(string VarName, string Value)
		{
			if (String.IsNullOrEmpty(CommandUtils.GetEnvVar(VarName)))
			{
				Environment.SetEnvironmentVariable(VarName, Value);
			}
		}

		/// <summary>
		/// Gets environment variables set by a batch file.
		/// </summary>
		/// <param name="BatchFileName">Filename that sets the environment variables</param>
		/// <param name="AlsoSet">True if found variables should be automatically set withing this process.</param>
		/// <returns>Dictionary of environment variables set by the batch file.</returns>
		public static CaselessDictionary<string> GetEnvironmentVariablesFromBatchFile(string BatchFileName, bool AlsoSet = false)
		{
			if (File.Exists(BatchFileName))
			{
				// Create a wrapper batch file that echoes environment variables to a text file
				var EnvOutputFileName = CommandUtils.CombinePaths(Path.GetTempPath(), "HarvestEnvVars.txt");
				var EnvReaderBatchFileName = CommandUtils.CombinePaths(Path.GetTempPath(), "HarvestEnvVars.bat");

				{
					var EnvReaderBatchFileContent = new List<string>();

					// Run 'vcvars32.bat' (or similar x64 version) to set environment variables
					EnvReaderBatchFileContent.Add(String.Format("call \"{0}\"", BatchFileName));

					// Pipe all environment variables to a file where we can read them in
					EnvReaderBatchFileContent.Add(String.Format("set >\"{0}\"", EnvOutputFileName));

					File.WriteAllLines(EnvReaderBatchFileName, EnvReaderBatchFileContent);
				}

				InternalUtils.SafeDeleteFile(EnvOutputFileName);
				CommandUtils.Run(EnvReaderBatchFileName, "");

				var Result = new CaselessDictionary<string>();
				// Load environment variables
				var EnvStringsFromFile = File.ReadAllLines(EnvOutputFileName);
				foreach (var EnvString in EnvStringsFromFile)
				{
					// Parse the environment variable name and value from the string ("name=value")
					int EqualSignPos = EnvString.IndexOf('=');
					var EnvironmentVariableName = EnvString.Substring(0, EqualSignPos);
					var EnvironmentVariableValue = EnvString.Substring(EqualSignPos + 1);

					if (Environment.GetEnvironmentVariable(EnvironmentVariableName) != EnvironmentVariableValue)
					{
						Result.Add(EnvironmentVariableName, EnvironmentVariableValue);
					}
					if (AlsoSet)
					{
						// Set the environment variable
						Environment.SetEnvironmentVariable(EnvironmentVariableName, EnvironmentVariableValue);
					}
				}
				return Result;
			}
			else
			{
				throw new AutomationException("BatchFile {0} does not exist!", BatchFileName);
			}
		}

		#endregion

		#region CommandLine

		/// <summary>
		/// Converts a list of arguments to a string where each argument is separated with a space character.
		/// </summary>
		/// <param name="Args">Arguments</param>
		/// <returns>Single string containing all arguments separated with a space.</returns>
		public static string ArgsToCommandLine(params object[] Args)
		{
			string Arguments = "";
			if (Args != null)
			{
				for (int Index = 0; Index < Args.Length; ++Index)
				{
					Arguments += Args[Index].ToString();
					if (Index < (Args.Length - 1))
					{
						Arguments += " ";
					}
				}
			}
			return Arguments;
		}

		/// <summary>
		/// Parses the argument list for a parameter and returns whether it is defined or not.
		/// </summary>
		/// <param name="ArgList">Argument list.</param>
		/// <param name="Param">Param to check for.</param>
		/// <returns>True if param was found, false otherwise.</returns>
		public static bool ParseParam(object[] ArgList, string Param)
		{
			foreach (object Arg in ArgList)
			{
				if (Arg.ToString().Equals(Param, StringComparison.InvariantCultureIgnoreCase))
				{
					return true;
				}
			}
			return false;
		}

		/// <summary>
		/// Parses the command's Params list for a parameter and returns whether it is defined or not.
		/// </summary>
		/// <param name="Param">Param to check for.</param>
		/// <returns>True if param was found, false otherwise.</returns>
		public bool ParseParam(string Param)
		{
			return ParseParam(Params, Param);
		}

		/// <summary>
		/// Parses the argument list for a parameter and reads its value. 
		/// Ex. ParseParamValue(Args, "map=")
		/// </summary>
		/// <param name="ArgList">Argument list.</param>
		/// <param name="Param">Param to read its value.</param>
		/// <returns>Returns the value or Default if the parameter was not found.</returns>
		public static string ParseParamValue(object[] ArgList, string Param, string Default = null)
		{
			if (!Param.EndsWith("="))
			{
				Param += "=";
			}

			foreach (object Arg in ArgList)
			{
				string ArgStr = Arg.ToString();
				if (ArgStr.StartsWith(Param, StringComparison.InvariantCultureIgnoreCase))
				{
					return ArgStr.Substring(Param.Length);
				}
			}
			return Default;
		}

		/// <summary>
		/// Parses the command's Params list for a parameter and reads its value. 
		/// Ex. ParseParamValue(Args, "map=")
		/// </summary>
		/// <param name="Param">Param to read its value.</param>
		/// <returns>Returns the value or Default if the parameter was not found.</returns>
		public string ParseParamValue(string Param, string Default = null)
		{
			return ParseParamValue(Params, Param, Default);
		}

		/// <summary>
		/// Parses the command's Params list for a parameter and reads its value. 
		/// Ex. ParseParamValue(Args, "map=")
		/// </summary>
		/// <param name="Param">Param to read its value.</param>
		/// <returns>Returns the value or Default if the parameter was not found.</returns>
		public int ParseParamInt(string Param, int Default = 0)
		{
			string num = ParseParamValue(Params, Param, Default.ToString());
			return int.Parse(num);
		}

		/// <summary>
		/// Makes sure path can be used as a command line param (adds quotes if it contains spaces)
		/// </summary>
		/// <param name="InPath">Path to convert</param>
		/// <returns></returns>
		public static string MakePathSafeToUseWithCommandLine(string InPath)
		{
			if (InPath.Contains(' ') && InPath[0] != '\"')
			{
				InPath = "\"" + InPath + "\"";
			}
			return InPath;
		}

		#endregion

		#region Other

		public static string EscapePath(string InPath)
		{
			return InPath.Replace(":", "").Replace("/", "+").Replace("\\", "+").Replace(" ", "+");
		}

		/// <summary>
		/// Checks if collection is either null or empty.
		/// </summary>
		/// <param name="Collection">Collection to check.</param>
		/// <returns>True if the collection is either nur or empty.</returns>
		public static bool IsNullOrEmpty(ICollection Collection)
		{
			return Collection == null || Collection.Count == 0;
		}

		/// <summary>
		/// List of available target platforms.
		/// </summary>
		public static UnrealBuildTool.UnrealTargetPlatform[] KnownTargetPlatforms
		{
			get
			{
				if (UBTTargetPlatforms == null || UBTTargetPlatforms.Length == 0)
				{
					UBTTargetPlatforms = new UnrealBuildTool.UnrealTargetPlatform[UnrealBuildTool.UEBuildPlatform.BuildPlatformDictionary.Count];
					int Index = 0;
					foreach (var Platform in UnrealBuildTool.UEBuildPlatform.BuildPlatformDictionary)
					{
						UBTTargetPlatforms[Index++] = Platform.Key;
					}
				}
				return UBTTargetPlatforms;
			}
		}
		private static UnrealBuildTool.UnrealTargetPlatform[] UBTTargetPlatforms;

		#endregion

		#region Properties

		/// <summary>
		/// Command line parameters for this command (empty by non-null by default)
		/// </summary>
		private object[] CommandLineParams = new object[0];
		public object[] Params
		{
			get { return CommandLineParams; }
			set { CommandLineParams = value; }
		}

		/// <summary>
		/// Path to the AutomationTool executable.
		/// </summary>
		public static string ExeFilename
		{
			get { return InternalUtils.ExecutingAssemblyLocation; }
		}

		/// <summary>
		/// Directory where the AutomationTool executable sits.
		/// </summary>
		public static string ExeDirectory
		{
			get { return InternalUtils.ExecutingAssemblyDirectory; }
		}

		/// <summary>
		/// Current directory.
		/// </summary>
		public static string CurrentDirectory
		{
			get { return Environment.CurrentDirectory; }
			set { ChDir(value); }
		}

		/// <summary>
		/// Checks if this command is running on a build machine.
		/// </summary>
		public static bool IsBuildMachine
		{
			get { return Automation.IsBuildMachine; }
		}

		#endregion


        public static string RootSharedTempStorageDirectory()
        {
            string StorageDirectory = "";
            if (UnrealBuildTool.Utils.IsRunningOnMono)
            {
                StorageDirectory = "/Volumes/Builds";
            }
            else
            {
                StorageDirectory = CombinePaths("P:", "Builds");
            }
            return StorageDirectory;
        }

        public static bool DirectoryExistsAndIsWritable_NoExceptions(string Dir)
        {
            if (!DirectoryExists_NoExceptions(Dir))
            {
				Log(System.Diagnostics.TraceEventType.Information, "Directory {0} does not exist", Dir);
				return false;
			}

            try
            {
				string Filename = CombinePaths(Dir, Guid.NewGuid().ToString() + ".Temp.txt");
				string NativeFilename = ConvertSeparators(PathSeparator.Default, Filename);
				using(StreamWriter Writer = new StreamWriter(NativeFilename))
				{
					Writer.Write("Test");
				}
				if(File.Exists(NativeFilename))
				{
		            DeleteFile_NoExceptions(Filename, true);
		            Log(System.Diagnostics.TraceEventType.Information, "Directory {0} is writable", Dir);
					return true;
				}
			}
			catch(Exception)
			{
			}

			Log(System.Diagnostics.TraceEventType.Information, "Directory {0} is not writable", Dir);
			return false;
		}

        static Dictionary<string, string> ResolveCache = new Dictionary<string, string>();
        public static string ResolveSharedBuildDirectory(string GameFolder)
        {
            if (ResolveCache.ContainsKey(GameFolder))
            {
                return ResolveCache[GameFolder];
            }
            string Root = RootSharedTempStorageDirectory();
            string Result = CombinePaths(Root, GameFolder);
            if (String.IsNullOrEmpty(GameFolder) || !Robust_DirectoryExistsAndIsWritable_NoExceptions(Result))
            {
                string GameStr = "Game";
                bool HadGame = false;
                if (GameFolder.EndsWith(GameStr, StringComparison.InvariantCultureIgnoreCase))
                {
                    string ShortFolder = GameFolder.Substring(0, GameFolder.Length - GameStr.Length);
                    Result = CombinePaths(Root, ShortFolder);
                    HadGame = true;
                }
                if (!HadGame || !Robust_DirectoryExistsAndIsWritable_NoExceptions(Result))
                {
                    Result = CombinePaths(Root, "UE4");
                    if (!Robust_DirectoryExistsAndIsWritable_NoExceptions(Result))
                    {
                        throw new AutomationException("Could not find an appropriate shared temp folder {0}", Result);
                    }
                }
            }
            ResolveCache.Add(GameFolder, Result);
            return Result;
        }

        public static void CleanFormalBuilds(string DirectoryForThisBuild, string CLString = "", int MaximumDaysToKeepTempStorage = 4)
        {
            if (CLString == "" && (!IsBuildMachine || !DirectoryForThisBuild.StartsWith(RootSharedTempStorageDirectory()) || !P4Enabled))
            {
                return;
            }
            try
            {
                if (P4Enabled && CLString == "")
                {
                    CLString = P4Env.ChangelistString;
                }
                string ParentDir = Path.GetDirectoryName(CombinePaths(DirectoryForThisBuild));
                if (!DirectoryExists_NoExceptions(ParentDir))
                {
                    throw new AutomationException("Not cleaning formal builds, because the parent directory {0} does not exist.", ParentDir);
                }
                string MyDir = Path.GetFileName(CombinePaths(DirectoryForThisBuild));
                int CLStart = MyDir.IndexOf(CLString);
                if (CLStart < 0)
                {
                    throw new AutomationException("Not cleaning formal builds, because the directory {0} does not contain the CL {1}.", DirectoryForThisBuild, CLString);
                }
                string StartString = MyDir.Substring(0, CLStart);
                string EndString = MyDir.Substring(CLStart + CLString.Length);


                DirectoryInfo DirInfo = new DirectoryInfo(ParentDir);
                var TopLevelDirs = DirInfo.GetDirectories();
                Log("Looking for directories to delete in {0}   {1} dirs", ParentDir, TopLevelDirs.Length);
                foreach (var TopLevelDir in TopLevelDirs)
                {
                    if (DirectoryExists_NoExceptions(TopLevelDir.FullName))
                    {
                        var JustDir = Path.GetFileName(CombinePaths(TopLevelDir.FullName));
                        if (JustDir.StartsWith(StartString, StringComparison.InvariantCultureIgnoreCase) && (String.IsNullOrEmpty(EndString) || JustDir.EndsWith(EndString, StringComparison.InvariantCultureIgnoreCase)))
                        {
                            string CLPart = JustDir.Substring(StartString.Length, JustDir.Length - StartString.Length - EndString.Length);
                            if (CLPart.Contains("-PF-") || // always delete preflights
                                (!CLPart.Contains("-") && !CLPart.Contains("+"))) // never delete anything else that is weird, this is probably another branch
                            {
                                DirectoryInfo ThisDirInfo = new DirectoryInfo(TopLevelDir.FullName);
                                bool bOld = false;

                                if ((DateTime.UtcNow - ThisDirInfo.CreationTimeUtc).TotalDays > MaximumDaysToKeepTempStorage)
                                {
                                    bOld = true;
                                }
                                if (bOld)
                                {
                                    Log("Deleting temp storage directory {0}, because it is more than {1} days old.", TopLevelDir.FullName, MaximumDaysToKeepTempStorage);
                                    DeleteDirectory_NoExceptions(true, TopLevelDir.FullName);
                                }
                                else
                                {
                                    Log("Not Deleteing temp storage directory {0}, because it is less than {1} days old.", TopLevelDir.FullName, MaximumDaysToKeepTempStorage);
                                }
                            }
                            else
                            {
                                Log("skipping {0}, because the CL part {1} had weird characters", JustDir, CLPart);
                            }
                        }
                        else
                        {
                            Log("skipping {0}, because it didn't start with {1} or end with {2}", JustDir, StartString, EndString);
                        }
                    }
                }
            }
            catch (Exception Ex)
            {
                Log(System.Diagnostics.TraceEventType.Warning, "Unable to Clean Directory with DirectoryForThisBuild {0}", DirectoryForThisBuild);
                Log(System.Diagnostics.TraceEventType.Warning, " Exception was {0}", LogUtils.FormatException(Ex));
            }
        }

		/// <summary>
		/// Returns the generic name for a given platform (eg. "Windows" for Win32/Win64)
		/// </summary>
		/// <param name="Platform">Specific platform</param>
		public static string GetGenericPlatformName(UnrealBuildTool.UnrealTargetPlatform Platform)
		{
			if(Platform == UnrealTargetPlatform.Win32 || Platform == UnrealTargetPlatform.Win64)
			{
				return "Windows";
			}
			else
			{
				return Enum.GetName(typeof(UnrealBuildTool.UnrealTargetPlatform), Platform);
			}
		}

		/// <summary>
		/// Creates a zip file containing the given input files
		/// </summary>
		/// <param name="ZipFileName">Filename for the zip</param>
		/// <param name="Filter">Filter which selects files to be included in the zip</param>
		/// <param name="BaseDirectory">Base directory to store relative paths in the zip file to</param>
		public static void ZipFiles(string ZipFileName, string BaseDirectory, FileFilter Filter)
		{
			Ionic.Zip.ZipFile Zip = new Ionic.Zip.ZipFile();
			foreach(string FilteredFile in Filter.ApplyToDirectory(BaseDirectory, true))
			{
				Zip.AddFile(Path.Combine(BaseDirectory, FilteredFile), Path.GetDirectoryName(FilteredFile));
			}
			CommandUtils.CreateDirectory(Path.GetDirectoryName(ZipFileName));
			Zip.Save(ZipFileName);
		}

		/// <summary>
		/// Extracts the contents of a zip file
		/// </summary>
		/// <param name="ZipFileName">Name of the zip file</param>
		/// <param name="BaseDirectory">Output directory</param>
		/// <returns>List of files written</returns>
		public static IEnumerable<string> UnzipFiles(string ZipFileName, string BaseDirectory)
		{
			Ionic.Zip.ZipFile Zip = new Ionic.Zip.ZipFile(ZipFileName);

			// For some reason, calling ExtractAll() under Mono throws an exception from a call to Directory.CreateDirectory(). Manually extract all the files instead.
			List<string> OutputFileNames = new List<string>();
			foreach(Ionic.Zip.ZipEntry Entry in Zip.Entries)
			{
				string OutputFileName = Path.Combine(BaseDirectory, Entry.FileName);
				Directory.CreateDirectory(Path.GetDirectoryName(OutputFileName));
				using(FileStream OutputStream = new FileStream(OutputFileName, FileMode.Create, FileAccess.Write))
				{
					Entry.Extract(OutputStream);
				}
				OutputFileNames.Add(OutputFileName);
			}
			return OutputFileNames;
		}
	}



	/// <summary>
	/// Use with "using" syntax to push and pop directories in a convenient, exception-safe way
	/// </summary>
	public class PushedDirectory : IDisposable
	{
		public PushedDirectory(string DirectoryName)
		{
			CommandUtils.PushDir(DirectoryName);
		}

		public void Dispose()
		{
			CommandUtils.PopDir();
			GC.SuppressFinalize(this);
		}
	}

    /// <summary>
    /// Helper class to associate a file and its contents
    /// </summary>
    public class EMSFileInfo
    {
        public string FileName { get; set; }
        public byte[] Bytes { get; set; }
    }

    /// <summary>
    /// Wrapper class for the enumerate files JSON response from MCP
    /// </summary>
    [DataContract]
    public sealed class EnumerationResponse
    {
        [DataMember(Name = "doNotCache", IsRequired = true)]
        public Boolean DoNotCache { get; set; }

        [DataMember(Name = "uniqueFilename", IsRequired = true)]
        public string UniqueFilename { get; set; }

        [DataMember(Name = "filename", IsRequired = true)]
        public string Filename { get; set; }

        [DataMember(Name = "hash", IsRequired = true)]
        public string Hash { get; set; }

        [DataMember(Name = "length", IsRequired = true)]
        public long Length { get; set; }

        [DataMember(Name = "uploaded", IsRequired = true)]
        public string Uploaded { get; set; }
    }

	/// <summary>
	/// Code signing
	/// </summary>
	[Help("NoSign", "Skips signing of code/content files.")]
	public class CodeSign
	{
		/// <summary>
		/// If so, what is the signing identity to search for?
		/// </summary>
		public static string SigningIdentity = "Epic Games";

		/// <summary>
		/// Should we use the machine store?
		/// </summary>
		public static bool bUseMachineStoreInsteadOfUserStore = false;

		/// <summary>
		/// How long to keep re-trying code signing for
		/// </summary>
		public static TimeSpan CodeSignTimeOut = new TimeSpan(0, 3, 0); // Keep trying to sign one file for up to 3 minutes

		/// <summary>
		/// Code signs the specified file
		/// </summary>
		public static void SignSingleExecutableIfEXEOrDLL(string Filename, bool bIgnoreExtension = false)
		{
            if (UnrealBuildTool.Utils.IsRunningOnMono)
            {
                CommandUtils.Log(TraceEventType.Information, String.Format("Can't sign '{0}', we are running under mono.", Filename));
                return;
            }
            if (!CommandUtils.FileExists(Filename))
			{
				throw new AutomationException("Can't sign '{0}', file does not exist.", Filename);
			}
			// Make sure the file isn't read-only
			FileInfo TargetFileInfo = new FileInfo(Filename);

			// Executable extensions
			List<string> Extensions = new List<string>();
			Extensions.Add(".dll");
			Extensions.Add(".exe");

			bool IsExecutable = bIgnoreExtension;

			foreach (var Ext in Extensions)
			{
				if (TargetFileInfo.FullName.EndsWith(Ext, StringComparison.InvariantCultureIgnoreCase))
				{
					IsExecutable = true;
					break;
				}
			}
			if (!IsExecutable)
			{
				CommandUtils.Log(TraceEventType.Verbose, String.Format("Won't sign '{0}', not an executable.", TargetFileInfo.FullName));
				return;
			}

			string SignToolName = null;
			if (WindowsPlatform.Compiler == WindowsCompiler.VisualStudio2013)
			{
				SignToolName = "C:/Program Files (x86)/Windows Kits/8.1/bin/x86/SignTool.exe";
			}
			else if (WindowsPlatform.Compiler == WindowsCompiler.VisualStudio2012)
			{
				SignToolName = "C:/Program Files (x86)/Windows Kits/8.0/bin/x86/SignTool.exe";
			}


			if (!File.Exists(SignToolName))
			{
				throw new AutomationException("SignTool not found at '{0}' (are you missing the Windows SDK?)", SignToolName);
			}

			TargetFileInfo.IsReadOnly = false;

			// Code sign the executable
			string TimestampServer = "http://timestamp.verisign.com/scripts/timestamp.dll";

			string SpecificStoreArg = bUseMachineStoreInsteadOfUserStore ? " /sm" : "";

			//@TODO: Verbosity choosing
			//  /v will spew lots of info
			//  /q does nothing on success and minimal output on failure
			string CodeSignArgs = String.Format("sign{0} /a /n \"{1}\" /t {2} /d \"{3}\" /v \"{4}\"", SpecificStoreArg, SigningIdentity, TimestampServer, TargetFileInfo.Name, TargetFileInfo.FullName);

			DateTime StartTime = DateTime.Now;

			int NumTrials = 0;
			for (; ; )
			{
				ProcessResult Result = CommandUtils.Run(SignToolName, CodeSignArgs, null, CommandUtils.ERunOptions.AllowSpew);
				++NumTrials;

				if (Result.ExitCode != 1)
				{
					if (Result.ExitCode == 2)
					{
						CommandUtils.Log(TraceEventType.Error, String.Format("Signtool returned a warning."));
					}
					// Success!
					break;
				}
				else
				{
					// Keep retrying until we run out of time
					TimeSpan RunTime = DateTime.Now - StartTime;
					if (RunTime > CodeSignTimeOut)
					{
						throw new AutomationException("Failed to sign executable '{0}' {1} times over a period of {2}", TargetFileInfo.FullName, NumTrials, RunTime);
					}
				}
			}
		}

		/// <summary>
		/// Code signs the specified file or folder
		/// </summary>
		public static void SignMacFileOrFolder(string InPath, bool bIgnoreExtension = false)
		{
			bool bExists = CommandUtils.FileExists(InPath) || CommandUtils.DirectoryExists(InPath);
			if (!bExists)
			{
				throw new AutomationException("Can't sign '{0}', file or folder does not exist.", InPath);
			}

			// @todo: OS X 10.9.5/Xcode 6 can't sign libsteam_api.dylib, so we temporarily disable signing of the editor and games,
			// which code sign individual files (contrary to the Launcher, which signs the whole app bundle)
			if (CommandUtils.FileExists(InPath))
			{
				return;
			}

			// Executable extensions
			List<string> Extensions = new List<string>();
			Extensions.Add(".dylib");
			Extensions.Add(".app");

			bool IsExecutable = bIgnoreExtension || (Path.GetExtension(InPath) == "" && !InPath.EndsWith("PkgInfo"));

			foreach (var Ext in Extensions)
			{
				if (InPath.EndsWith(Ext, StringComparison.InvariantCultureIgnoreCase))
				{
					IsExecutable = true;
					break;
				}
			}
			if (!IsExecutable)
			{
				CommandUtils.Log(TraceEventType.Verbose, String.Format("Won't sign '{0}', not an executable.", InPath));
				return;
			}

			string SignToolName = "codesign";

			string CodeSignArgs = String.Format("-f --deep -s \"{0}\" -v \"{1}\"", "Developer ID Application", InPath);

			DateTime StartTime = DateTime.Now;

			int NumTrials = 0;
			for (; ; )
			{
				ProcessResult Result = CommandUtils.Run(SignToolName, CodeSignArgs, null, CommandUtils.ERunOptions.AllowSpew);
				int ExitCode = Result.ExitCode;
				++NumTrials;

				if (ExitCode == 0)
				{
					// Success!
					break;
				}
				else
				{
					// Keep retrying until we run out of time
					TimeSpan RunTime = DateTime.Now - StartTime;
					if (RunTime > CodeSignTimeOut)
					{
						throw new AutomationException("Failed to sign '{0}' {1} times over a period of {2}", InPath, NumTrials, RunTime);
					}
				}
			}
		}

		/// <summary>
		/// Codesigns multiple files, but skips anything that's not an EXE or DLL file
		/// Will automatically skip signing if -NoSign is specified in the command line.
		/// </summary>
		/// <param name="Files">List of files to sign</param>
		public static void SignMultipleIfEXEOrDLL(BuildCommand Command, List<string> Files)
		{
			if (!Command.ParseParam("NoSign"))
			{
				CommandUtils.Log("Signing up to {0} files...", Files.Count);
				UnrealBuildTool.UnrealTargetPlatform TargetPlatform = UnrealBuildTool.BuildHostPlatform.Current.Platform;
				if (TargetPlatform == UnrealBuildTool.UnrealTargetPlatform.Mac)
				{
					foreach (var File in Files)
					{
						SignMacFileOrFolder(File);
					}
				}
				else
				{
					List<string> FilesToSign = new List<string>();
					foreach (string File in Files)
					{
						if (!(Path.GetDirectoryName(File).Replace("\\", "/")).Contains("Binaries/XboxOne"))
						{
							FilesToSign.Add(File);
						}						
					}
					SignMultipleFilesIfEXEOrDLL(FilesToSign);
				}
			}
			else
			{
				CommandUtils.Log("Skipping signing {0} files due to -nosign.", Files.Count);
			}
		}

		public static void SignListFilesIfEXEOrDLL(string FilesToSign)
		{
			string SignToolName = null;
			if (WindowsPlatform.Compiler == WindowsCompiler.VisualStudio2013)
			{
				SignToolName = "C:/Program Files (x86)/Windows Kits/8.1/bin/x86/SignTool.exe";
			}
			else if (WindowsPlatform.Compiler == WindowsCompiler.VisualStudio2012)
			{
				SignToolName = "C:/Program Files (x86)/Windows Kits/8.0/bin/x86/SignTool.exe";
			}


			if (!File.Exists(SignToolName))
			{
				throw new AutomationException("SignTool not found at '{0}' (are you missing the Windows SDK?)", SignToolName);
			}

			// Code sign the executable
			string TimestampServer = "http://timestamp.verisign.com/scripts/timestamp.dll";

			string SpecificStoreArg = bUseMachineStoreInsteadOfUserStore ? " /sm" : "";	
			//@TODO: Verbosity choosing
			//  /v will spew lots of info
			//  /q does nothing on success and minimal output on failure
			string CodeSignArgs = String.Format("sign{0} /a /n \"{1}\" /t {2} /d /v {3}", SpecificStoreArg, SigningIdentity, TimestampServer, FilesToSign);

			DateTime StartTime = DateTime.Now;

			int NumTrials = 0;
			for (; ; )
			{
				ProcessResult Result = CommandUtils.Run(SignToolName, CodeSignArgs, null, CommandUtils.ERunOptions.AllowSpew);
				++NumTrials;

				if (Result.ExitCode != 1)
				{
					if (Result.ExitCode == 2)
					{
						CommandUtils.Log(TraceEventType.Error, String.Format("Signtool returned a warning."));
					}
					// Success!
					break;
				}
				else
				{
					// Keep retrying until we run out of time
					TimeSpan RunTime = DateTime.Now - StartTime;
					if (RunTime > CodeSignTimeOut)
					{
						throw new AutomationException("Failed to sign executables {0} times over a period of {1}", NumTrials, RunTime);
					}
				}
			}
		}

		public static void SignMultipleFilesIfEXEOrDLL(List<string> Files, bool bIgnoreExtension = false)
		{
			if (UnrealBuildTool.Utils.IsRunningOnMono)
			{
				CommandUtils.Log(TraceEventType.Information, String.Format("Can't sign we are running under mono."));
				return;
			}
			List<string> FinalFiles = new List<string>();
			foreach (string Filename in Files)
			{
				// Make sure the file isn't read-only
				FileInfo TargetFileInfo = new FileInfo(Filename);

				// Executable extensions
				List<string> Extensions = new List<string>();
				Extensions.Add(".dll");
				Extensions.Add(".exe");

				bool IsExecutable = bIgnoreExtension;

				foreach (var Ext in Extensions)
				{
					if (TargetFileInfo.FullName.EndsWith(Ext, StringComparison.InvariantCultureIgnoreCase))
					{
						IsExecutable = true;
						break;
					}
				}
				if (IsExecutable && CommandUtils.FileExists(Filename))
				{
					FinalFiles.Add(Filename);
				}
			}			

			StringBuilder FilesToSignBuilder = new StringBuilder();
			List<string> FinalListSignStrings = new List<string>();
			foreach(string File in FinalFiles)
			{
				FilesToSignBuilder.Append("\"" + File + "\" ");				
				if(FilesToSignBuilder.Length > 1900)
				{
					string AddFilesToFinalList = FilesToSignBuilder.ToString();
					FinalListSignStrings.Add(AddFilesToFinalList);
					FilesToSignBuilder.Clear();
				}
			}
			foreach(string FilesToSign in FinalListSignStrings)
			{
				SignListFilesIfEXEOrDLL(FilesToSign);
			}

		}
	}

}