001/*
002 * Copyright (C) 2012 eXo Platform SAS.
003 *
004 * This is free software; you can redistribute it and/or modify it
005 * under the terms of the GNU Lesser General Public License as
006 * published by the Free Software Foundation; either version 2.1 of
007 * the License, or (at your option) any later version.
008 *
009 * This software is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * You should have received a copy of the GNU Lesser General Public
015 * License along with this software; if not, write to the Free
016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018 */
019
020package org.crsh.processor.jline;
021
022import org.crsh.shell.ShellProcessContext;
023import org.crsh.shell.ShellResponse;
024import org.crsh.text.Chunk;
025import org.crsh.text.Style;
026import org.crsh.text.Text;
027
028import java.io.IOException;
029import java.util.concurrent.CountDownLatch;
030import java.util.concurrent.atomic.AtomicReference;
031
032class JLineProcessContext implements ShellProcessContext {
033
034  /** . */
035  private static final Character NO_ECHO = (char)0;
036
037  /** . */
038  final JLineProcessor processor;
039
040  /** . */
041  final CountDownLatch latch = new CountDownLatch(1);
042
043  /** . */
044  final AtomicReference<ShellResponse> resp = new AtomicReference<ShellResponse>();
045
046  public JLineProcessContext(JLineProcessor processor) {
047    this.processor = processor;
048  }
049
050  public boolean takeAlternateBuffer() {
051    if (!processor.useAlternate) {
052      processor.useAlternate = true;
053
054      // To get those codes I captured the output of telnet running top
055      // on OSX:
056      // 1/ sudo /usr/libexec/telnetd -debug #run telnet
057      // 2/ telnet localhost >output.txt
058      // 3/ type username + enter
059      // 4/ type password + enter
060      // 5/ type top + enter
061      // 6/ ctrl-c
062      // 7/ type exit + enter
063
064      // Save screen and erase
065      processor.writer.print("\033[?47h"); // Switches to the alternate screen
066      // writer.print("\033[1;43r");
067//      processor.writer.print("\033[m"); // Reset to normal (Sets SGR parameters : 0 m == m)
068      // writer.print("\033[4l");
069      // writer.print("\033[?1h");
070      // writer.print("\033[=");
071//      processor.writer.print("\033[H"); // Move the cursor to home
072//      processor.writer.print("\033[2J"); // Clear screen
073//      processor.writer.flush();
074    }
075    return true;
076  }
077
078  public boolean releaseAlternateBuffer() {
079    if (processor.useAlternate) {
080      processor.useAlternate = false;
081      processor.writer.print("\033[?47l"); // Switches back to the normal screen
082    }
083    return true;
084  }
085
086  public int getWidth() {
087    return processor.reader.getTerminal().getWidth();
088  }
089
090  public int getHeight() {
091    return processor.reader.getTerminal().getHeight();
092  }
093
094  public String getProperty(String name) {
095    return null;
096  }
097
098  public String readLine(String msg, boolean echo) {
099    try {
100      if (echo) {
101        return processor.reader.readLine(msg);
102      } else {
103        return processor.reader.readLine(msg, NO_ECHO);
104      }
105    }
106    catch (IOException e) {
107      return null;
108    }
109  }
110
111  public Class<Chunk> getConsumedType() {
112    return Chunk.class;
113  }
114
115  public void write(Chunk chunk) throws IOException {
116    provide(chunk);
117  }
118
119  public void provide(Chunk element) throws IOException {
120    if (element instanceof Text) {
121      Text textChunk = (Text)element;
122      processor.writer.append(textChunk.getText());
123    } else if (element instanceof Style) {
124      try {
125        ((Style)element).writeAnsiTo(processor.writer);
126      }
127      catch (IOException ignore) {
128      }
129    } else {
130
131
132      // Clear screen
133      processor.writer.print("\033[2J");
134      processor.writer.print("\033[1;1H");
135    }
136  }
137
138  public void flush() {
139    processor.writer.flush();
140  }
141
142  public void end(ShellResponse response) {
143    try {
144      resp.set(response);
145      latch.countDown();
146    }
147    finally {
148      // Release screen if it wasn't done
149      releaseAlternateBuffer();
150    }
151  }
152}