// This code is derived from jcifs smb client library <jcifs at samba dot org>
// Ported by J. Arturo <webmaster at komodosoft dot net>
//  
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
// 
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
// 
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
using System.IO;
using SharpCifs.Util.Sharpen;

namespace SharpCifs.Smb
{
    /// <summary>This <code>OutputStream</code> can write bytes to a file on an SMB file server.
    /// </summary>
    /// <remarks>This <code>OutputStream</code> can write bytes to a file on an SMB file server.
    /// </remarks>
    public class SmbFileOutputStream : OutputStream
    {
        private SmbFile _file;

        private bool _append;

        private bool _useNtSmbs;

        private int _openFlags;

        private int _access;

        private int _writeSize;

        private long _fp;

        private byte[] _tmp = new byte[1];

        private SmbComWriteAndX _reqx;

        private SmbComWriteAndXResponse _rspx;

        private SmbComWrite _req;

        private SmbComWriteResponse _rsp;

        /// <summary>
        /// Creates an
        /// <see cref="System.IO.OutputStream">System.IO.OutputStream</see>
        /// for writing to a file
        /// on an SMB server addressed by the URL parameter. See
        /// <see cref="SmbFile">SmbFile</see>
        /// for a detailed description and examples of
        /// the smb URL syntax.
        /// </summary>
        /// <param name="url">An smb URL string representing the file to write to</param>
        /// <exception cref="SharpCifs.Smb.SmbException"></exception>
        /// <exception cref="System.UriFormatException"></exception>
        /// <exception cref="UnknownHostException"></exception>
        public SmbFileOutputStream(string url) : this(url, false)
        {
        }

        /// <summary>
        /// Creates an
        /// <see cref="System.IO.OutputStream">System.IO.OutputStream</see>
        /// for writing bytes to a file on
        /// an SMB server represented by the
        /// <see cref="SmbFile">SmbFile</see>
        /// parameter. See
        /// <see cref="SmbFile">SmbFile</see>
        /// for a detailed description and examples of
        /// the smb URL syntax.
        /// </summary>
        /// <param name="file">An <code>SmbFile</code> specifying the file to write to</param>
        /// <exception cref="SharpCifs.Smb.SmbException"></exception>
        /// <exception cref="System.UriFormatException"></exception>
        /// <exception cref="UnknownHostException"></exception>
        public SmbFileOutputStream(SmbFile file) : this(file, false)
        {
        }

        /// <summary>
        /// Creates an
        /// <see cref="System.IO.OutputStream">System.IO.OutputStream</see>
        /// for writing bytes to a file on an
        /// SMB server addressed by the URL parameter. See
        /// <see cref="SmbFile">SmbFile</see>
        /// for a detailed description and examples of the smb URL syntax. If the
        /// second argument is <code>true</code>, then bytes will be written to the
        /// end of the file rather than the beginning.
        /// </summary>
        /// <param name="url">An smb URL string representing the file to write to</param>
        /// <param name="append">Append to the end of file</param>
        /// <exception cref="SharpCifs.Smb.SmbException"></exception>
        /// <exception cref="System.UriFormatException"></exception>
        /// <exception cref="UnknownHostException"></exception>
        public SmbFileOutputStream(string url, bool append) : this(new SmbFile(url), append)
        {
        }

        /// <summary>
        /// Creates an
        /// <see cref="System.IO.OutputStream">System.IO.OutputStream</see>
        /// for writing bytes to a file
        /// on an SMB server addressed by the <code>SmbFile</code> parameter. See
        /// <see cref="SmbFile">SmbFile</see>
        /// for a detailed description and examples of
        /// the smb URL syntax. If the second argument is <code>true</code>, then
        /// bytes will be written to the end of the file rather than the beginning.
        /// </summary>
        /// <param name="file">An <code>SmbFile</code> representing the file to write to</param>
        /// <param name="append">Append to the end of file</param>
        /// <exception cref="SharpCifs.Smb.SmbException"></exception>
        /// <exception cref="System.UriFormatException"></exception>
        /// <exception cref="UnknownHostException"></exception>
        public SmbFileOutputStream(SmbFile file, bool append)
            : this(file,
                   append,
                   append
                        ? SmbFile.OCreat | SmbFile.OWronly | SmbFile.OAppend
                        : SmbFile.OCreat | SmbFile.OWronly | SmbFile.OTrunc)
        {
        }

        /// <summary>
        /// Creates an
        /// <see cref="System.IO.OutputStream">System.IO.OutputStream</see>
        /// for writing bytes to a file
        /// on an SMB server addressed by the <code>SmbFile</code> parameter. See
        /// <see cref="SmbFile">SmbFile</see>
        /// for a detailed description and examples of
        /// the smb URL syntax.
        /// <p>
        /// The second parameter specifies how the file should be shared. If
        /// <code>SmbFile.FILE_NO_SHARE</code> is specified the client will
        /// have exclusive access to the file. An additional open command
        /// from jCIFS or another application will fail with the "file is being
        /// accessed by another process" error. The <code>FILE_SHARE_READ</code>,
        /// <code>FILE_SHARE_WRITE</code>, and <code>FILE_SHARE_DELETE</code> may be
        /// combined with the bitwise OR '|' to specify that other peocesses may read,
        /// write, and/or delete the file while the jCIFS user has the file open.
        /// </summary>
        /// <param name="url">An smb URL representing the file to write to</param>
        /// <param name="shareAccess">File sharing flag: <code>SmbFile.FILE_NOSHARE</code> or any combination of <code>SmbFile.FILE_READ</code>, <code>SmbFile.FILE_WRITE</code>, and <code>SmbFile.FILE_DELETE</code>
        /// </param>
        /// <exception cref="Jcifs.Smb.SmbException"></exception>
        /// <exception cref="System.UriFormatException"></exception>
        /// <exception cref="UnknownHostException"></exception>
        public SmbFileOutputStream(string url, int shareAccess)
            : this(new SmbFile(url, string.Empty, null, shareAccess), false)
        {
        }

        /// <exception cref="SharpCifs.Smb.SmbException"></exception>
        /// <exception cref="System.UriFormatException"></exception>
        /// <exception cref="UnknownHostException"></exception>
        internal SmbFileOutputStream(SmbFile file, bool append, int openFlags)
        {
            this._file = file;
            this._append = append;
            this._openFlags = openFlags;
            _access = ((int)(((uint)openFlags) >> 16)) & 0xFFFF;
            if (append)
            {
                try
                {
                    _fp = file.Length();
                }
                catch (SmbAuthException sae)
                {
                    throw;
                }
                catch (SmbException)
                {
                    _fp = 0L;
                }
            }
            if (file is SmbNamedPipe && file.Unc.StartsWith("\\pipe\\"))
            {
                file.Unc = Runtime.Substring(file.Unc, 5);
                file.Send(new TransWaitNamedPipe("\\pipe" + file.Unc),
                          new TransWaitNamedPipeResponse());
            }
            file.Open(openFlags,
                      _access | SmbConstants.FileWriteData,
                      SmbFile.AttrNormal,
                      0);
            this._openFlags &= ~(SmbFile.OCreat | SmbFile.OTrunc);
            _writeSize = file.Tree.Session.transport.SndBufSize - 70;
            _useNtSmbs = file.Tree.Session.transport.HasCapability(SmbConstants.CapNtSmbs);
            if (_useNtSmbs)
            {
                _reqx = new SmbComWriteAndX();
                _rspx = new SmbComWriteAndXResponse();
            }
            else
            {
                _req = new SmbComWrite();
                _rsp = new SmbComWriteResponse();
            }
        }

        /// <summary>
        /// Closes this output stream and releases any system resources associated
        /// with it.
        /// </summary>
        /// <remarks>
        /// Closes this output stream and releases any system resources associated
        /// with it.
        /// </remarks>
        /// <exception cref="System.IO.IOException">if a network error occurs</exception>
        public override void Close()
        {
            _file.Close();
            _tmp = null;
        }

        /// <summary>Writes the specified byte to this file output stream.</summary>
        /// <remarks>Writes the specified byte to this file output stream.</remarks>
        /// <exception cref="System.IO.IOException">if a network error occurs</exception>
        public override void Write(int b)
        {
            _tmp[0] = unchecked((byte)b);
            Write(_tmp, 0, 1);
        }

        /// <summary>
        /// Writes b.length bytes from the specified byte array to this
        /// file output stream.
        /// </summary>
        /// <remarks>
        /// Writes b.length bytes from the specified byte array to this
        /// file output stream.
        /// </remarks>
        /// <exception cref="System.IO.IOException">if a network error occurs</exception>
        public override void Write(byte[] b)
        {
            Write(b, 0, b.Length);
        }

        public virtual bool IsOpen()
        {
            return _file.IsOpen();
        }

        /// <exception cref="System.IO.IOException"></exception>
        internal virtual void EnsureOpen()
        {
            // ensure file is open
            if (_file.IsOpen() == false)
            {
                _file.Open(_openFlags,
                           _access | SmbConstants.FileWriteData,
                           SmbFile.AttrNormal,
                           0);
                if (_append)
                {
                    _fp = _file.Length();
                }
            }
        }

        /// <summary>
        /// Writes len bytes from the specified byte array starting at
        /// offset off to this file output stream.
        /// </summary>
        /// <remarks>
        /// Writes len bytes from the specified byte array starting at
        /// offset off to this file output stream.
        /// </remarks>
        /// <param name="b">The array</param>
        /// <exception cref="System.IO.IOException">if a network error occurs</exception>
        public override void Write(byte[] b, int off, int len)
        {
            if (_file.IsOpen() == false && _file is SmbNamedPipe)
            {
                _file.Send(new TransWaitNamedPipe("\\pipe" + _file.Unc),
                           new TransWaitNamedPipeResponse());
            }
            WriteDirect(b, off, len, 0);
        }

        /// <summary>Just bypasses TransWaitNamedPipe - used by DCERPC bind.</summary>
        /// <remarks>Just bypasses TransWaitNamedPipe - used by DCERPC bind.</remarks>
        /// <exception cref="System.IO.IOException"></exception>
        public virtual void WriteDirect(byte[] b, int off, int len, int flags)
        {
            if (len <= 0)
            {
                return;
            }
            if (_tmp == null)
            {
                throw new IOException("Bad file descriptor");
            }
            EnsureOpen();
            /*
            if (file.log.level >= 4)
			{
				file.log.WriteLine("write: fid=" + file.fid + ",off=" + off + ",len=" + len);
			}
            */
            int w;
            do
            {
                w = len > _writeSize ? _writeSize : len;
                if (_useNtSmbs)
                {
                    _reqx.SetParam(_file.Fid, _fp, len - w, b, off, w);
                    if ((flags & 1) != 0)
                    {
                        _reqx.SetParam(_file.Fid, _fp, len, b, off, w);
                        _reqx.WriteMode = 0x8;
                    }
                    else
                    {
                        _reqx.WriteMode = 0;
                    }
                    _file.Send(_reqx, _rspx);
                    _fp += _rspx.Count;
                    len -= (int)_rspx.Count;
                    off += (int)_rspx.Count;
                }
                else
                {
                    _req.SetParam(_file.Fid, _fp, len - w, b, off, w);
                    _fp += _rsp.Count;
                    len -= (int)_rsp.Count;
                    off += (int)_rsp.Count;
                    _file.Send(_req, _rsp);
                }
            }
            while (len > 0);
        }
    }
}