Cosmos/source/Cosmos.System.Plugs/System/IO/PathImpl.cs

using System;
using System.IO;

using Cosmos.Common;
using Cosmos.IL2CPU.Plugs;
using Cosmos.System.FileSystem;
using Cosmos.System.FileSystem.VFS;

namespace Cosmos.System.Plugs.System.IO
{
    [Plug(Target = typeof(Path))]
    public static class PathImpl
    {
        public static void Cctor(
            //[FieldAccess(Name = "System.Char[] System.IO.Path.InvalidFileNameChars")] ref char[] aInvalidFileNameChars,
            //[FieldAccess(Name = "System.Char[] System.IO.Path.InvalidPathCharsWithAdditionalChecks")] ref char[] aInvalidPathCharsWithAdditionalChecks,
            //[FieldAccess(Name = "System.Char System.IO.Path.PathSeparator")] ref char aPathSeparator,
            //[FieldAccess(Name = "System.Char[] System.IO.Path.RealInvalidPathChars")] ref char[] aRealInvalidPathChars,
            //[FieldAccess(Name = "System.Int32 System.IO.Path.MaxPath")] ref int aMaxPath
            [FieldAccess(Name = "System.Char System.IO.Path.AltDirectorySeparatorChar")] ref char
                aAltDirectorySeparatorChar,
            [FieldAccess(Name = "System.Char System.IO.Path.DirectorySeparatorChar")] ref char aDirectorySeparatorChar,
            [FieldAccess(Name = "System.Char System.IO.Path.VolumeSeparatorChar")] ref char aVolumeSeparatorChar)
        {
            //aInvalidFileNameChars = VFSManager.GetInvalidFileNameChars();
            //aInvalidPathCharsWithAdditionalChecks = VFSManager.GetInvalidPathCharsWithAdditionalChecks();
            //aPathSeparator = VFSManager.GetPathSeparator();
            //aRealInvalidPathChars = VFSManager.GetRealInvalidPathChars();
            //aMaxPath = VFSManager.GetMaxPath();
            aAltDirectorySeparatorChar = VFSManager.GetAltDirectorySeparatorChar();
            aDirectorySeparatorChar = VFSManager.GetDirectorySeparatorChar();
            aVolumeSeparatorChar = VFSManager.GetVolumeSeparatorChar();
        }

        public static string ChangeExtension(string aPath, string aExtension)
        {
            if (aPath != null)
            {
                CheckInvalidPathChars(aPath, false);
                string xText = aPath;
                int xNum = aPath.Length;
                while (--xNum >= 0)
                {
                    char xC = aPath[xNum];
                    if (xC == '.')
                    {
                        xText = aPath.Substring(0, xNum);
                        break;
                    }
                    if (xC == Path.DirectorySeparatorChar || xC == Path.AltDirectorySeparatorChar
                        || xC == Path.VolumeSeparatorChar)
                    {
                        break;
                    }
                }
                if (aExtension != null && aPath.Length != 0)
                {
                    if (aExtension.Length == 0 || aExtension[0] != '.')
                    {
                        xText += ".";
                    }
                    xText += aExtension;
                }
                FileSystemHelpers.Debug("Path.ChangeExtension", "aPath =", aPath, ", aExtension =", aExtension, ", result =", xText);
                return xText;
            }
            return null;
        }

        public static void CheckInvalidPathChars(string aPath, bool aCheckAdditional)
        {
            if (aPath == null)
            {
                throw new ArgumentNullException("aPath");
            }

            if (HasIllegalCharacters(aPath, aCheckAdditional))
            {
                throw new ArgumentException("The path contains invalid characters.", "aPath");
            }
        }

        public static void CheckSearchPattern(string aSearchPattern)
        {
            int xNum;
            while ((xNum = aSearchPattern.IndexOf("..", StringComparison.Ordinal)) != -1)
            {
                if (xNum + 2 == aSearchPattern.Length)
                {
                    throw new ArgumentException("The search pattern is invalid.", aSearchPattern);
                }

                if (aSearchPattern[xNum + 2] == Path.DirectorySeparatorChar
                    || aSearchPattern[xNum + 2] == Path.AltDirectorySeparatorChar)
                {
                    throw new ArgumentException("The search pattern is invalid.", aSearchPattern);
                }

                aSearchPattern = aSearchPattern.Substring(xNum + 2);
            }
        }

        public static string Combine(string aPath1, string aPath2)
        {
            if (aPath1 == null || aPath2 == null)
            {
                throw new ArgumentNullException((aPath1 == null) ? "path1" : "path2");
            }

            CheckInvalidPathChars(aPath1, false);
            CheckInvalidPathChars(aPath2, false);
            string result = CombineNoChecks(aPath1, aPath2);
            FileSystemHelpers.Debug("Path.Combine", "aPath1 =", aPath1, ", aPath2 =", aPath2, ", result =", result);
            return result;
        }

        public static string CombineNoChecks(string aPath1, string aPath2)
        {
            if (aPath2.Length == 0)
            {
                FileSystemHelpers.Debug("Path.CombineNoChecks", "aPath2 has 0 length, result =", aPath1);
                return aPath1;
            }

            if (aPath1.Length == 0)
            {
                FileSystemHelpers.Debug("Path.CombineNoChecks", "aPath1 has 0 length, result =", aPath2);
                return aPath2;
            }

            if (IsPathRooted(aPath2))
            {
                FileSystemHelpers.Debug("Path.CombineNoChecks", "aPath2 is root, result =", aPath2);
                return aPath2;
            }

            string xResult = string.Empty; 
            char xC = aPath1[aPath1.Length - 1];
            if (xC != Path.DirectorySeparatorChar && xC != Path.AltDirectorySeparatorChar
                && xC != Path.VolumeSeparatorChar)
            {
                xResult = string.Concat(aPath1, "\\", aPath2);
                FileSystemHelpers.Debug("Path.CombineNoChecks", "aPath1 =", aPath1, ", aPath2 =", aPath2, ", result =", xResult);
                return xResult;
            }

            xResult = string.Concat(aPath1, aPath2);
            FileSystemHelpers.Debug("Path.CombineNoChecks", "aPath1 =", aPath1, ", aPath2 =", aPath2, ", result =", xResult);
            return xResult;
        }

        public static string GetDirectoryName(string aPath)
        {
            if (aPath != null)
            {
                CheckInvalidPathChars(aPath, false);
                string xPath = NormalizePath(aPath, false);
                int xRootLength = GetRootLength(xPath);
                int xNum = xPath.Length;
                FileSystemHelpers.Debug("GetDirectoryName of ", aPath,  " xRootLength ", xRootLength,  "xPathLenght " + xNum);

                // If lenght of aPath is the same of the lenght of the Root Path is the root Path itself!
                if (xNum == xRootLength)
                {
                    FileSystemHelpers.Debug("Path.GetDirectoryName", "aPath =", aPath, " is the root directory");
                    return null;
                }

                if (xNum > xRootLength)
                {
                    while (xNum > xRootLength && xPath[--xNum] != Path.DirectorySeparatorChar
                           && xPath[xNum] != Path.AltDirectorySeparatorChar)
                    {
                    }
                }
                string result = xPath.Substring(0, xNum);
                FileSystemHelpers.Debug("Path.GetDirectoryName", "aPath =", aPath, ", result =", result);
                return result;
            }

            FileSystemHelpers.Debug("Path.GetDirectoryName", "aPath is null");
            return null;
        }

        public static string GetExtension(string aPath)
        {
            if (aPath == null)
            {
                return null;
            }

            CheckInvalidPathChars(aPath, false);
            int xLength = aPath.Length;
            int xNum = xLength;
            while (--xNum >= 0)
            {
                char xC = aPath[xNum];
                if (xC == '.')
                {
                    if (xNum != xLength - 1)
                    {
                        return aPath.Substring(xNum + 1, xLength - xNum);
                    }

                    return string.Empty;
                }

                if (xC == Path.DirectorySeparatorChar || xC == Path.AltDirectorySeparatorChar
                    || xC == Path.VolumeSeparatorChar)
                {
                    break;
                }
            }
            return string.Empty;
        }

        public static string GetFileName(string aPath)
        {
            if (aPath != null)
            {
                CheckInvalidPathChars(aPath, false);
                int xLength = aPath.Length;
                int xNum = xLength;
                while (--xNum >= 0)
                {
                    char xC = aPath[xNum];
                    if (xC == Path.DirectorySeparatorChar || xC == Path.AltDirectorySeparatorChar
                        || xC == Path.VolumeSeparatorChar)
                    {
                        //String result = aPath.Substring(xNum + 1, xLength - xNum - 1);
                        //FileSystemHelpers.Debug("Path.GetFileName", "result is ", result);
                        return aPath.Substring(xNum + 1, xLength - xNum - 1);
                    }
                }
            }

            FileSystemHelpers.Debug("Returning aPath ", aPath);
            return aPath;
        }

        public static string GetFileNameWithoutExtension(string aPath)
        {
            aPath = GetFileName(aPath);
            if (aPath == null)
            {
                return null;
            }
            int xLength;
            if ((xLength = aPath.LastIndexOf('.')) == -1)
            {
                return aPath;
            }
            return aPath.Substring(0, xLength);
        }

        public static string GetFullPath(string aPath)
        {
            if (aPath == null)
            {
                FileSystemHelpers.Debug("Path.GetFullPath", "aPath is null");
                throw new ArgumentNullException("aPath");
            }

            string result = NormalizePath(aPath, true);
            FileSystemHelpers.Debug("Path.GetFullPath", "aPath =", aPath, ", result =", result);
            return result;
        }

        public static char[] GetInvalidFileNameChars()
        {
            return VFSManager.GetInvalidFileNameChars();
        }

        public static char[] GetInvalidPathChars()
        {
            return VFSManager.GetRealInvalidPathChars();
        }

        public static string GetPathRoot(string aPath)
        {
            if (aPath == null)
            {
                FileSystemHelpers.Debug("Path.GetPathRoot", "aPath is null");
                throw new ArgumentNullException("aPath");
            }

            aPath = NormalizePath(aPath, false);
            int xRootLength = GetRootLength(aPath);
            string xResult = aPath.Substring(0, xRootLength);
            if (xResult[xResult.Length - 1] != Path.DirectorySeparatorChar)
            {
                xResult = string.Concat(xResult, Path.DirectorySeparatorChar.ToString());
            }

            FileSystemHelpers.Debug("Path.GetPathRoot", "aPath =", aPath, ", xResult =", xResult);
            return xResult;
        }

        public static string GetRandomFileName()
        {
            return "random.tmp";
        }

        public static int GetRootLength(string aPath)
        {
            if (aPath == null)
            {
                FileSystemHelpers.Debug("Path.GetRootLength", "aPath is null");
                throw new ArgumentNullException("aPath");
            }

            CheckInvalidPathChars(aPath, false);
            int i = 0;
            int length = aPath.Length;
            if (length >= 1 && IsDirectorySeparator(aPath[0]))
            {
                i = 1;
                if (length >= 2 && IsDirectorySeparator(aPath[1]))
                {
                    i = 2;
                    int num = 2;
                    while (i < length)
                    {
                        if ((aPath[i] == Path.DirectorySeparatorChar || aPath[i] == Path.AltDirectorySeparatorChar)
                            && --num <= 0)
                        {
                            break;
                        }
                        i++;
                    }
                }
            }
            else if (length >= 2 && aPath[1] == Path.VolumeSeparatorChar)
            {
                i = 2;
                if (length >= 3 && IsDirectorySeparator(aPath[2]))
                {
                    i++;
                }
            }

            FileSystemHelpers.Debug("Path.GetRootLength", "result =", i.ToString());
            return i;
        }

        public static string GetTempFileName()
        {
            return "tempfile.tmp";
        }

        public static string GetTempPath()
        {
            return @"\Temp";
        }

        public static bool HasExtension(string aPath)
        {
            if (aPath != null)
            {
                CheckInvalidPathChars(aPath, false);
                int xNum = aPath.Length;
                while (--xNum >= 0)
                {
                    char xC = aPath[xNum];
                    if (xC == '.')
                    {
                        return xNum != aPath.Length - 1;
                    }

                    if (xC == Path.DirectorySeparatorChar || xC == Path.AltDirectorySeparatorChar
                        || xC == Path.VolumeSeparatorChar)
                    {
                        break;
                    }
                }
            }

            return false;
        }

        public static bool HasIllegalCharacters(string aPath, bool aCheckAdditional)
        {
            if (aCheckAdditional)
            {
                char[] xInvalidWithAdditional = VFSManager.GetInvalidPathCharsWithAdditionalChecks();
                for (int i = 0; i < xInvalidWithAdditional.Length; i++)
                {
                    for (int j = 0; j < aPath.Length; j++)
                    {
                        if (xInvalidWithAdditional[i] == aPath[j])
                        {
                            return true;
                        }
                    }
                }
            }

            char[] xInvalid = VFSManager.GetRealInvalidPathChars();
            for (int i = 0; i < xInvalid.Length; i++)
            {
                for (int j = 0; j < aPath.Length; j++)
                {
                    if (xInvalid[i] == aPath[j])
                    {
                        return true;
                    }
                }
            }

            return false;
        }

        public static bool IsDirectorySeparator(char aC)
        {
            if (aC.ToString() == Path.DirectorySeparatorChar.ToString())
            {
                return true;
            }

            if (aC.ToString() == Path.AltDirectorySeparatorChar.ToString())
            {
                return true;
            }

            return false;
        }

        public static bool IsPathRooted(string aPath)
        {
            if (aPath != null)
            {
                CheckInvalidPathChars(aPath, false);
                int xLength = aPath.Length;
                if ((xLength >= 1
                     && (aPath[0] == Path.DirectorySeparatorChar || aPath[0] == Path.AltDirectorySeparatorChar))
                    || (xLength >= 2 && aPath[1] == Path.VolumeSeparatorChar))
                {
                    return true;
                }
            }

            return false;
        }

        public static bool IsRelative(string aPath)
        {
            if (aPath == null)
            {
                throw new ArgumentNullException("aPath");
            }

            if (aPath.Length < 3)
            {
                return true;
            }

            if (aPath[1] != Path.VolumeSeparatorChar)
            {
                return true;
            }

            if (aPath[2] != Path.DirectorySeparatorChar)
            {
                return true;
            }

            return false;
        }

        public static string NormalizePath(string aPath, bool aFullCheck)
        {
            if (aPath == null)
            {
                FileSystemHelpers.Debug("Path.NormalizePath", "aPath is null");
                throw new ArgumentNullException("aPath");
            }

            string result = aPath;
            if (IsRelative(result))
            {
                result = Directory.GetCurrentDirectory() + Path.DirectorySeparatorChar.ToString() + result;
                FileSystemHelpers.Debug("Path.NormalizePath", "aPath is relative, aPath =", aPath, ", result =", result);
            }

            if (IsDirectorySeparator(result[result.Length - 1]))
            {
                FileSystemHelpers.Debug("Found directory seprator");
                result = result.Remove(result.Length - 1);
            }

            FileSystemHelpers.Debug("Path.NormalizePath", "aPath =", aPath, ", result =", result);
            return result;
        }
    }
}