/*

* Copyright (c) 2004-2008 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*

*/

using System;

using System.IO;

namespace SymBuildParsingLib.Utils

{

	public class SymFileSystemUtils

	{

		public static bool FileExists( string aFileName )

		{

			FileInfo info = new FileInfo( aFileName );

			return info.Exists;

		}

		public static bool IsDriveValid( string aDrive )

		{

			bool valid = false;

			//

			if	( aDrive.Length > 0 )

			{

				valid = IsDriveValid( aDrive[ 0 ] );

			}

			//

			return valid;

		}

		public static bool IsDriveValid( char aDrive )

		{

			string driveAsLowerCaseString = new string( aDrive, 1 ).ToLower();

			int drive = (int) driveAsLowerCaseString[ 0 ];

			//

			int firstDrive = (int) 'a';

			int lastDrive = (int) 'z';

			//

			bool valid = ( drive >= firstDrive && drive <= lastDrive );

			return valid;

		}

		public static string AddPathSeparator( string aDir )

		{

			string ret = aDir.Trim();

			//

			int length = ret.Length;

			if	( length > 0 )

			{

				if	( ret[ length - 1 ] != Path.DirectorySeparatorChar )

				{

					ret += Path.DirectorySeparatorChar;

				}

			}

			//

			return ret;

		}

		public static string DirectoryFromPath( string aName )

		{

			// C:\system\data\wibble.txt

			// Returns C:\System\Data\

			string ret = Path.GetDirectoryName( aName ) + Path.DirectorySeparatorChar;

			return ret;

		}

		public static string DriveFromPath( string aName )

		{

			// C:\\system\\data\\wibble.txt => C:

			string drive = "C:";

			//

			if	( Path.IsPathRooted( aName ) == true )

			{

				drive = Path.GetPathRoot( aName );

				// Check its got a drive

				if	( drive.Length < 2 || drive[ 1 ] != ':' )

				{

					throw new ArgumentException( "Path \'" + aName + "\' does not have a drive as its root" );

				}

				drive = drive.Substring( 0, 2 );

			}

			else

			{

				throw new ArgumentException( "Path \'" + aName + "\' does not contain a root" );

			}

			//

			return drive;

		}

		public static string PopDir( string aDir )

		{

			string ret = DirectoryFromPath( aDir );

			ret = AddPathSeparator( ret );

			DirectoryInfo info = new DirectoryInfo( ret );

			ret = info.Parent.FullName;

			ret = AddPathSeparator( ret );

			return ret;

		}

		public static string MergePaths( string aBasePath, string aOtherPath )

		{

			#region Examples

			// "X:\Wibble\"                 +   "+Build\Generated"      => "X:\<epocroot>\EPOC32\Build\Generated";

			// "X:\Wibble\"                 +   "..\something\"         => "X:\something\"

			// "X:\Wibble\"                 +   "..something\"          => "X:\Wibble\something"

			// "X:\Wibble\"                 +   "\something\"           => "X:\something\"

			// "X:\Wibble\"                 +   ".\something\"          => "X:\wibble\something\"

			// "X:\Wibble\"                 +   "something\"            => "X:\wibble\something\"

			// "X:\Wibble\"                 +   "."                     => "X:\Wibble\"

			// "X:\Wibble\"                 +   "\"                     => "X:\Wibble\"

			// "X:\Wibble\"                 +   "a"                     => "X:\Wibble\a"

			// "X:\Wibble\Whatsit.txt"      +   "X:\Wibble\"            => "X:\Wibble\"

			// "X:\Wibble\Whatsit.txt"      +   "NextWibble.txt"        => "X:\Wibble\NextWibble.txt"

			#endregion

			string otherPath = aOtherPath;

			//

			string ret = aBasePath.Trim();

			ret = DirectoryFromPath(ret);

			ret = AddPathSeparator(ret);

			//

			int length = otherPath.Length;

			if	(length >= 1)

			{

				char firstChar = otherPath[0];

				if  ( firstChar == '.' )

				{

					bool needToPushRemainder = false;

					bool finishedCheckingForDirPops = false;

					//

					while( finishedCheckingForDirPops == false )

					{

						// Assume we only go around once

						finishedCheckingForDirPops = true;

						firstChar = otherPath[0];

						length = otherPath.Length;

						//

						if	( firstChar == '.' )

						{

							if	( length >= 2 )

							{

								char secondChar = otherPath[1];

								if	( secondChar == '.' )

								{

									// Keep popping directories from the base path (now stored in 'ret')

									// while there are "..\" sub-strings remaining at the start of the 

									// "other path"

									ret = PopDir(ret);

									// Tidy up the "otherPath" to remove the two dots which we just parsed

									int subStringPos = 2;

									if	(length >= 3 && otherPath[2] == '\\')

									{

										subStringPos = 3;

									}

									//

									needToPushRemainder = true;

									otherPath = otherPath.Substring( subStringPos );

									finishedCheckingForDirPops = false;

								}

							}

						}

					}

					if  ( needToPushRemainder )

					{

						ret += otherPath;

					}

				}

				else if ( firstChar == '\\' )

				{

					if	(length > 1)

					{

						// Root path

						ret = DriveFromPath( ret );

						ret += otherPath;

					}

				}

				else if ( firstChar == '+' && otherPath.Length > 0 )

				{

					// Need to add epoc root and then EPOC32, then the path without the +

					string actualPathPart = otherPath.Substring(1);

					if	( actualPathPart.Length > 0 && actualPathPart[0] == '\\' )

					{

						actualPathPart = actualPathPart.Substring(1);

					}

					string epocRootValue = SymEnvironment.EpocRoot;

					ret = DriveFromPath(ret);

					ret += AddPathSeparator( epocRootValue );

					ret += AddPathSeparator( SymEnvironment.Epoc32Path );

					ret += AddPathSeparator( actualPathPart );

				}

				else

				{

					if  ( otherPath[ length-1 ] == '\\' )

					{

						// Assume we already have a complete path

						ret = otherPath;

					}

					else

					{

						ret += otherPath;

					}

				}

			}

			/*

			const string nameAndExt = FileNameAndExtension(ret);

			const bool containsDot = (nameAndExt.find_last_of('.') != string::npos);

			if  (!FileExists(ret) && ret.length() && ret[ret.length()-1] != '\\' && containsDot)

				{

				cout << "WARNING - possible file merge error:" << endl;

				cout << "\tMerging: " << aBasePath << " with: " << aOtherPath << endl;

				cout << "\t\t -> " << ret << endl << endl;

				}

			*/

			return ret;

		}

	}

}