/**
 * This program will demonstrate the sftp protocol support. If everything works fine, you will get a
 * prompt 'sftp>'. 'help' command will show available command. In current implementation, the
 * destination path for 'get' and 'put' commands must be a file, not a directory.
 */
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import com.jcraft.jsch.SftpATTRS;
import com.jcraft.jsch.SftpException;
import com.jcraft.jsch.SftpProgressMonitor;
import com.jcraft.jsch.SftpStatVFS;
import com.jcraft.jsch.UIKeyboardInteractive;
import com.jcraft.jsch.UserInfo;
import java.awt.Container;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
import javax.swing.ProgressMonitor;

public class Sftp {
  public static void main(String[] arg) {

    try {
      JSch jsch = new JSch();

      String host = null;
      if (arg.length > 0) {
        host = arg[0];
      } else {
        host = JOptionPane.showInputDialog("Enter username@hostname",
            System.getProperty("user.name") + "@localhost");
      }
      String user = host.substring(0, host.indexOf('@'));
      host = host.substring(host.indexOf('@') + 1);
      int port = 22;

      Session session = jsch.getSession(user, host, port);

      // username and password will be given via UserInfo interface.
      UserInfo ui = new MyUserInfo();
      session.setUserInfo(ui);

      session.connect();

      Channel channel = session.openChannel("sftp");
      channel.connect();
      ChannelSftp c = (ChannelSftp) channel;

      java.io.InputStream in = System.in;
      java.io.PrintStream out = System.out;

      java.util.List<String> cmds = new java.util.ArrayList<>();
      byte[] buf = new byte[1024];
      int i;
      String str;
      int level = 0;

      while (true) {
        out.print("sftp> ");
        cmds.clear();
        i = in.read(buf, 0, 1024);
        if (i <= 0)
          break;

        i--;
        if (i > 0 && buf[i - 1] == 0x0d)
          i--;
        // str = new String(buf, 0, i);
        // System.out.println("|" + str + "|");
        int s = 0;
        for (int ii = 0; ii < i; ii++) {
          if (buf[ii] == ' ') {
            if (ii - s > 0) {
              cmds.add(new String(buf, s, ii - s));
            }
            while (ii < i) {
              if (buf[ii] != ' ')
                break;
              ii++;
            }
            s = ii;
          }
        }
        if (s < i) {
          cmds.add(new String(buf, s, i - s));
        }
        if (cmds.isEmpty())
          continue;

        String cmd = cmds.get(0);
        if (cmd.equals("quit")) {
          c.quit();
          break;
        }
        if (cmd.equals("exit")) {
          c.exit();
          break;
        }
        if (cmd.equals("rekey")) {
          session.rekey();
          continue;
        }
        if (cmd.equals("compression")) {
          if (cmds.size() < 2) {
            out.println("compression level: " + level);
            continue;
          }
          try {
            level = Integer.parseInt(cmds.get(1));
            if (level == 0) {
              session.setConfig("compression.s2c", "none");
              session.setConfig("compression.c2s", "none");
            } else {
              session.setConfig("compression.s2c", "zlib@openssh.com,zlib,none");
              session.setConfig("compression.c2s", "zlib@openssh.com,zlib,none");
            }
          } catch (Exception e) {
          }
          session.rekey();
          continue;
        }
        if (cmd.equals("cd") || cmd.equals("lcd")) {
          if (cmds.size() < 2)
            continue;
          String path = cmds.get(1);
          try {
            if (cmd.equals("cd"))
              c.cd(path);
            else
              c.lcd(path);
          } catch (SftpException e) {
            System.out.println(e);
          }
          continue;
        }
        if (cmd.equals("rm") || cmd.equals("rmdir") || cmd.equals("mkdir")) {
          if (cmds.size() < 2)
            continue;
          String path = cmds.get(1);
          try {
            if (cmd.equals("rm"))
              c.rm(path);
            else if (cmd.equals("rmdir"))
              c.rmdir(path);
            else
              c.mkdir(path);
          } catch (SftpException e) {
            System.out.println(e);
          }
          continue;
        }
        if (cmd.equals("chgrp") || cmd.equals("chown") || cmd.equals("chmod")) {
          if (cmds.size() != 3)
            continue;
          String path = cmds.get(2);
          int foo = 0;
          if (cmd.equals("chmod")) {
            byte[] bar = cmds.get(1).getBytes();
            for (int k : bar) {
              if (k < '0' || k > '7') {
                foo = -1;
                break;
              }
              foo <<= 3;
              foo |= (k - '0');
            }
            if (foo == -1)
              continue;
          } else {
            try {
              foo = Integer.parseInt(cmds.get(1));
            } catch (Exception e) {
              continue;
            }
          }
          try {
            if (cmd.equals("chgrp")) {
              c.chgrp(foo, path);
            } else if (cmd.equals("chown")) {
              c.chown(foo, path);
            } else if (cmd.equals("chmod")) {
              c.chmod(foo, path);
            }
          } catch (SftpException e) {
            System.out.println(e);
          }
          continue;
        }
        if (cmd.equals("pwd") || cmd.equals("lpwd")) {
          str = (cmd.equals("pwd") ? "Remote" : "Local");
          str += " working directory: ";
          if (cmd.equals("pwd"))
            str += c.pwd();
          else
            str += c.lpwd();
          out.println(str);
          continue;
        }
        if (cmd.equals("ls") || cmd.equals("dir")) {
          String path = ".";
          if (cmds.size() == 2)
            path = cmds.get(1);
          try {
            java.util.Vector<ChannelSftp.LsEntry> vv = c.ls(path);
            if (vv != null) {
              for (ChannelSftp.LsEntry le : vv) {
                // out.println(le);
                out.println(le.getLongname());
              }
            }
          } catch (SftpException e) {
            System.out.println(e);
          }
          continue;
        }
        if (cmd.equals("lls") || cmd.equals("ldir")) {
          String path = ".";
          if (cmds.size() == 2)
            path = cmds.get(1);
          try {
            java.io.File file = new java.io.File(path);
            if (!file.exists()) {
              out.println(path + ": No such file or directory");
              continue;
            }
            if (file.isDirectory()) {
              String[] list = file.list();
              for (String l : list) {
                out.println(l);
              }
              continue;
            }
            out.println(path);
          } catch (Exception e) {
            System.out.println(e);
          }
          continue;
        }
        if (cmd.equals("get") || cmd.equals("get-resume") || cmd.equals("get-append")
            || cmd.equals("put") || cmd.equals("put-resume") || cmd.equals("put-append")) {
          if (cmds.size() != 2 && cmds.size() != 3)
            continue;
          String p1 = cmds.get(1);
          // String p2 = p1;
          String p2 = ".";
          if (cmds.size() == 3)
            p2 = cmds.get(2);
          try {
            SftpProgressMonitor monitor = new MyProgressMonitor();
            if (cmd.startsWith("get")) {
              int mode = ChannelSftp.OVERWRITE;
              if (cmd.equals("get-resume")) {
                mode = ChannelSftp.RESUME;
              } else if (cmd.equals("get-append")) {
                mode = ChannelSftp.APPEND;
              }
              c.get(p1, p2, monitor, mode);
            } else {
              int mode = ChannelSftp.OVERWRITE;
              if (cmd.equals("put-resume")) {
                mode = ChannelSftp.RESUME;
              } else if (cmd.equals("put-append")) {
                mode = ChannelSftp.APPEND;
              }
              c.put(p1, p2, monitor, mode);
            }
          } catch (SftpException e) {
            System.out.println(e);
          }
          continue;
        }
        if (cmd.equals("ln") || cmd.equals("symlink") || cmd.equals("rename")
            || cmd.equals("hardlink")) {
          if (cmds.size() != 3)
            continue;
          String p1 = cmds.get(1);
          String p2 = cmds.get(2);
          try {
            if (cmd.equals("hardlink")) {
              c.hardlink(p1, p2);
            } else if (cmd.equals("rename"))
              c.rename(p1, p2);
            else
              c.symlink(p1, p2);
          } catch (SftpException e) {
            System.out.println(e);
          }
          continue;
        }
        if (cmd.equals("df")) {
          if (cmds.size() > 2)
            continue;
          String p1 = cmds.size() == 1 ? "." : cmds.get(1);
          SftpStatVFS stat = c.statVFS(p1);

          long size = stat.getSize();
          long used = stat.getUsed();
          long avail = stat.getAvailForNonRoot();
          long root_avail = stat.getAvail();
          long capacity = stat.getCapacity();

          System.out.println("Size: " + size);
          System.out.println("Used: " + used);
          System.out.println("Avail: " + avail);
          System.out.println("(root): " + root_avail);
          System.out.println("%Capacity: " + capacity);

          continue;
        }
        if (cmd.equals("stat") || cmd.equals("lstat")) {
          if (cmds.size() != 2)
            continue;
          String p1 = cmds.get(1);
          SftpATTRS attrs = null;
          try {
            if (cmd.equals("stat"))
              attrs = c.stat(p1);
            else
              attrs = c.lstat(p1);
          } catch (SftpException e) {
            System.out.println(e);
          }
          if (attrs != null) {
            out.println(attrs);
          } else {
          }
          continue;
        }
        if (cmd.equals("readlink")) {
          if (cmds.size() != 2)
            continue;
          String p1 = cmds.get(1);
          String filename = null;
          try {
            filename = c.readlink(p1);
            out.println(filename);
          } catch (SftpException e) {
            System.out.println(e);
          }
          continue;
        }
        if (cmd.equals("realpath")) {
          if (cmds.size() != 2)
            continue;
          String p1 = cmds.get(1);
          String filename = null;
          try {
            filename = c.realpath(p1);
            out.println(filename);
          } catch (SftpException e) {
            System.out.println(e);
          }
          continue;
        }
        if (cmd.equals("version")) {
          out.println("SFTP protocol version " + c.version());
          continue;
        }
        if (cmd.equals("help") || cmd.equals("?")) {
          out.println(help);
          continue;
        }
        out.println("unimplemented command: " + cmd);
      }
      session.disconnect();
    } catch (Exception e) {
      System.out.println(e);
    }
    System.exit(0);
  }

  public static class MyUserInfo implements UserInfo, UIKeyboardInteractive {
    @Override
    public String getPassword() {
      return passwd;
    }

    @Override
    public boolean promptYesNo(String str) {
      Object[] options = {"yes", "no"};
      int foo = JOptionPane.showOptionDialog(null, str, "Warning", JOptionPane.DEFAULT_OPTION,
          JOptionPane.WARNING_MESSAGE, null, options, options[0]);
      return foo == 0;
    }

    String passwd;
    JTextField passwordField = new JPasswordField(20);

    @Override
    public String getPassphrase() {
      return null;
    }

    @Override
    public boolean promptPassphrase(String message) {
      return true;
    }

    @Override
    public boolean promptPassword(String message) {
      Object[] ob = {passwordField};
      int result = JOptionPane.showConfirmDialog(null, ob, message, JOptionPane.OK_CANCEL_OPTION);
      if (result == JOptionPane.OK_OPTION) {
        passwd = passwordField.getText();
        return true;
      } else {
        return false;
      }
    }

    @Override
    public void showMessage(String message) {
      JOptionPane.showMessageDialog(null, message);
    }

    final GridBagConstraints gbc = new GridBagConstraints(0, 0, 1, 1, 1, 1,
        GridBagConstraints.NORTHWEST, GridBagConstraints.NONE, new Insets(0, 0, 0, 0), 0, 0);
    private Container panel;

    @Override
    public String[] promptKeyboardInteractive(String destination, String name, String instruction,
        String[] prompt, boolean[] echo) {
      panel = new JPanel();
      panel.setLayout(new GridBagLayout());

      gbc.weightx = 1.0;
      gbc.gridwidth = GridBagConstraints.REMAINDER;
      gbc.gridx = 0;
      panel.add(new JLabel(instruction), gbc);
      gbc.gridy++;

      gbc.gridwidth = GridBagConstraints.RELATIVE;

      JTextField[] texts = new JTextField[prompt.length];
      for (int i = 0; i < prompt.length; i++) {
        gbc.fill = GridBagConstraints.NONE;
        gbc.gridx = 0;
        gbc.weightx = 1;
        panel.add(new JLabel(prompt[i]), gbc);

        gbc.gridx = 1;
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.weighty = 1;
        if (echo[i]) {
          texts[i] = new JTextField(20);
        } else {
          texts[i] = new JPasswordField(20);
        }
        panel.add(texts[i], gbc);
        gbc.gridy++;
      }

      if (JOptionPane.showConfirmDialog(null, panel, destination + ": " + name,
          JOptionPane.OK_CANCEL_OPTION, JOptionPane.QUESTION_MESSAGE) == JOptionPane.OK_OPTION) {
        String[] response = new String[prompt.length];
        for (int i = 0; i < prompt.length; i++) {
          response[i] = texts[i].getText();
        }
        return response;
      } else {
        return null; // cancel
      }
    }
  }

  public static class MyProgressMonitor implements SftpProgressMonitor {
    ProgressMonitor monitor;
    long count = 0;
    long max = 0;

    @Override
    public void init(int op, String src, String dest, long max) {
      this.max = max;
      monitor = new ProgressMonitor(null,
          ((op == SftpProgressMonitor.PUT) ? "put" : "get") + ": " + src, "", 0, (int) max);
      count = 0;
      percent = -1;
      monitor.setProgress((int) this.count);
      monitor.setMillisToDecideToPopup(1000);
    }

    private long percent = -1;

    @Override
    public boolean count(long count) {
      this.count += count;

      if (percent >= this.count * 100 / max) {
        return true;
      }
      percent = this.count * 100 / max;

      monitor.setNote("Completed " + this.count + "(" + percent + "%) out of " + max + ".");
      monitor.setProgress((int) this.count);

      return !(monitor.isCanceled());
    }

    @Override
    public void end() {
      monitor.close();
    }
  }

  private static String help = "      Available commands:\n"
      + "      * means unimplemented command.\n"
      + "cd path                       Change remote directory to 'path'\n"
      + "lcd path                      Change local directory to 'path'\n"
      + "chgrp grp path                Change group of file 'path' to 'grp'\n"
      + "chmod mode path               Change permissions of file 'path' to 'mode'\n"
      + "chown own path                Change owner of file 'path' to 'own'\n"
      + "df [path]                     Display statistics for current directory or\n"
      + "                              filesystem containing 'path'\n"
      + "help                          Display this help text\n"
      + "get remote-path [local-path]  Download file\n"
      + "get-resume remote-path [local-path]  Resume to download file.\n"
      + "get-append remote-path [local-path]  Append remote file to local file\n"
      + "hardlink oldpath newpath      Hardlink remote file\n"
      + "*lls [ls-options [path]]      Display local directory listing\n"
      + "ln oldpath newpath            Symlink remote file\n"
      + "*lmkdir path                  Create local directory\n"
      + "lpwd                          Print local working directory\n"
      + "ls [path]                     Display remote directory listing\n"
      + "*lumask umask                 Set local umask to 'umask'\n"
      + "mkdir path                    Create remote directory\n"
      + "put local-path [remote-path]  Upload file\n"
      + "put-resume local-path [remote-path]  Resume to upload file\n"
      + "put-append local-path [remote-path]  Append local file to remote file.\n"
      + "pwd                           Display remote working directory\n"
      + "stat path                     Display info about path\n"
      + "exit                          Quit sftp\n" + "quit                          Quit sftp\n"
      + "rename oldpath newpath        Rename remote file\n"
      + "rmdir path                    Remove remote directory\n"
      + "rm path                       Delete remote file\n"
      + "symlink oldpath newpath       Symlink remote file\n"
      + "readlink path                 Check the target of a symbolic link\n"
      + "realpath path                 Canonicalize the path\n"
      + "rekey                         Key re-exchanging\n"
      + "compression level             Packet compression will be enabled\n"
      + "version                       Show SFTP version\n"
      + "?                             Synonym for help";
}