//
//  Class:			sftp
//	Current CLR:	4.0.30319.34209
//	System:			Microsoft Visual Studio 10.0
//	Author:			dani
// 	Created:		4/28/2015 8:53:41 AM
//
//	Copyright (c) 2015 Informatikbüro Daniel Schick. All rights reserved.

using log4net;
using System.Diagnostics;
using bsmd.database;
using WinSCP;
using System;
using System.Linq;
using System.Collections.Generic;

namespace bsmd.dakosy
{
    /// <summary>
    /// Hilfsklasse zur Kommunikation via SFTP. Wir machen es uns hier leicht und verwenden das beliebte WINSCP im 
    /// Process-Modus. (http://winscp.net/eng/docs/guide_dotnet)
    /// </summary>
    public static class SFtp
    {
        private static readonly ILog _log = LogManager.GetLogger(typeof(SFtp));
        
        public enum Direction
        {
            INCOMING,
            OUTGOING
        }

        public static void Put(string filename, string targetDir)
        {
            Process winscp = new Process();
            winscp.StartInfo.FileName = Properties.Settings.Default.WINSCPFullPath;
            winscp.StartInfo.Arguments = "/xmllog=\"" + Properties.Settings.Default.SFTPLog + "\"";
            winscp.StartInfo.UseShellExecute = false;
            winscp.StartInfo.RedirectStandardInput = true;
            winscp.StartInfo.RedirectStandardOutput = true;
            winscp.StartInfo.CreateNoWindow = true;
            winscp.Start();

            string dotlessFilename = filename.Substring(1);

            // Feed in the scripting commands
            winscp.StandardInput.WriteLine("option batch abort");
            winscp.StandardInput.WriteLine("option confirm off");
            winscp.StandardInput.WriteLine("open " + Properties.Settings.Default.SFTPSessionName);
            winscp.StandardInput.WriteLine("lcd " + Properties.Settings.Default.SFTPOutDir);
            // winscp.StandardInput.WriteLine("ls");
            if (targetDir != null)
                winscp.StandardInput.WriteLine("cd " + targetDir);
            winscp.StandardInput.WriteLine("put " + filename);
            winscp.StandardInput.WriteLine(string.Format("mv {0} {1}", filename, dotlessFilename));
            winscp.StandardInput.Close();

            // Collect all output
            string output = winscp.StandardOutput.ReadToEnd();
            _log.Debug(output);
            output = winscp.StandardError.ReadToEnd();
            if (!output.Trim().IsNullOrEmpty())
                _log.Warn(output);

            // Wait until WinSCP finishes
            winscp.WaitForExit();

            /*
            // Parse and interpret the XML log
            // (Note that in case of fatal failure the log file may not exist at all)
            XPathDocument log = new XPathDocument(Properties.Settings.Default.SFTPLog);
            XmlNamespaceManager ns = new XmlNamespaceManager(new NameTable());
            ns.AddNamespace("w", @"http://winscp.net/schema/session/1.0");
            XPathNavigator nav = log.CreateNavigator();

            // Success (0) or error?
            if (winscp.ExitCode != 0)
            {
                Console.WriteLine("Error occured");

                // See if there are any messages associated with the error
                foreach (XPathNavigator message in nav.Select("//w:message", ns))
                {
                    Console.WriteLine(message.Value);
                }
            }
            else
            {
                // It can be worth looking for directory listing even in case of
                // error as possibly only upload may fail

                XPathNodeIterator files = nav.Select("//w:file", ns);
                Console.WriteLine(string.Format("There are {0} files and subdirectories:", files.Count));
                foreach (XPathNavigator file in files)
                {
                    Console.WriteLine(file.SelectSingleNode("w:filename/@value", ns).Value);
                }
            }
            */
              
        }        

        private static Process StartWinSCPProcess()
        {
            Process winscp = new Process();
            winscp.StartInfo.FileName = Properties.Settings.Default.WINSCPFullPath;
            winscp.StartInfo.Arguments = "/xmllog=\"" + Properties.Settings.Default.SFTPLog + "\"";
            winscp.StartInfo.UseShellExecute = false;
            winscp.StartInfo.RedirectStandardInput = true;
            winscp.StartInfo.RedirectStandardOutput = true;
            winscp.StartInfo.RedirectStandardError = true;
            winscp.StartInfo.CreateNoWindow = true;
            //winscp.EnableRaisingEvents = true;
            //winscp.OutputDataReceived += (s, e) => { if (!e.Data.IsNullOrEmpty()) _log.Debug(e.Data); };
            //winscp.ErrorDataReceived += (s, e) => { if (!e.Data.IsNullOrEmpty()) _log.Warn(e.Data); };
            winscp.Start();
            //winscp.BeginErrorReadLine();
            //winscp.BeginOutputReadLine();

            return winscp;
        }

        public static void TransmitAllFiles(string remoteDir, string localDir, string host, string user, string keyPath, string hostkey)
        {
            try
            {
                SessionOptions sessionOptions = new SessionOptions();
                
                sessionOptions.Protocol = Protocol.Sftp;
                sessionOptions.HostName = host;
                sessionOptions.UserName = user;
                sessionOptions.SshPrivateKeyPath = keyPath;
                sessionOptions.SshHostKeyFingerprint = hostkey;

                using (Session session = new Session())
                {
                    session.Open(sessionOptions);

                    // upload
                    TransferOptions transferOptions = new TransferOptions();
                    transferOptions.TransferMode = TransferMode.Binary;

                    TransferOperationResult transferResult = session.PutFiles(localDir, remoteDir, false, transferOptions);

                    transferResult.Check();

                    foreach(TransferEventArgs tea in transferResult.Transfers.Cast<TransferEventArgs>())
                    {
                        _log.InfoFormat("Upload of {0} successful", tea.FileName);
                    }                       
                }

            }
            catch(Exception e)
            {
                _log.Error(e);
            }
        }

        public static void ReceiveAllFiles(string remoteDir, string localDir, string host, string user, string keyPath, string hostkey)
        {
            try
            {
                SessionOptions sessionOptions = new SessionOptions();

                sessionOptions.Protocol = Protocol.Sftp;
                sessionOptions.HostName = host;
                sessionOptions.UserName = user;
                sessionOptions.SshPrivateKeyPath = keyPath;
                sessionOptions.SshHostKeyFingerprint = hostkey;

                using (Session session = new Session())
                {
                    session.Open(sessionOptions);

                    // upload
                    TransferOptions transferOptions = new TransferOptions();
                    transferOptions.TransferMode = TransferMode.Binary;
                    
                    TransferOperationResult transferResult = session.GetFiles(remoteDir, localDir, false, transferOptions);                                       
                    transferResult.Check();

                    foreach (TransferEventArgs tea in transferResult.Transfers.Cast<TransferEventArgs>())
                    {
                        _log.InfoFormat("Download of {0} successful", tea.FileName);
                    }

                    if (transferResult.Transfers.Count > 0)
                    {
                        RemovalOperationResult removalResult = session.RemoveFiles(remoteDir + "/*.*");
                        if ((removalResult.IsSuccess) && (removalResult.Removals.Count > 0))
                        {
                            _log.InfoFormat("Removed {0} downloaded files on remote host", removalResult.Removals);
                        }
                        if (!removalResult.IsSuccess)
                        {
                            _log.WarnFormat("RemoveFiles was not successful, {0} failures", removalResult.Failures.Count);
                        }
                    }
                }

            }
            catch (Exception e)
            {
                _log.Error(e);
            }
        }

        public static void TransmitAll(string remoteDir, string localDir, Direction direction, string openCommand)
        {
            Process winscp = StartWinSCPProcess();            

            // Feed in the scripting commands
            winscp.StandardInput.WriteLine("option batch abort");
            winscp.StandardInput.WriteLine("option confirm off");
            winscp.StandardInput.WriteLine(openCommand);
            winscp.StandardInput.WriteLine("lcd " + localDir);
            // winscp.StandardInput.WriteLine("ls");
            if (remoteDir != null)
                winscp.StandardInput.WriteLine("cd " + remoteDir);
            if(direction == Direction.INCOMING)
                winscp.StandardInput.WriteLine("get *.xml");
            if(direction == Direction.OUTGOING)
                winscp.StandardInput.WriteLine("put *.xml");                     
            winscp.StandardInput.Close();

            // Collect all output
            string output = winscp.StandardOutput.ReadToEnd();
            _log.Debug(output);
            output = winscp.StandardError.ReadToEnd();
            if (!output.Trim().IsNullOrEmpty())
                _log.Warn(output);
            // Wait until WinSCP finishes
            winscp.WaitForExit();
            if(winscp.ExitCode != 0)
            {
                _log.Warn("WinSCP exited with an error");
            }
        }

        public static void RemoveProcessedFile(string remoteDir, string filename, string openCommand)
        {
            Process winscp = StartWinSCPProcess();            

            // Feed in the scripting commands
            winscp.StandardInput.WriteLine("option batch abort");
            winscp.StandardInput.WriteLine("option confirm off");
            winscp.StandardInput.WriteLine(openCommand);
            
            // winscp.StandardInput.WriteLine("ls");
            if (remoteDir != null)
                winscp.StandardInput.WriteLine("cd " + remoteDir);
            winscp.StandardInput.WriteLine("rm " + filename);            
            winscp.StandardInput.Close();            

            // Wait until WinSCP finishes
            winscp.WaitForExit();
        }
    }
}