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    
020    package org.crsh.processor.jline;
021    
022    import org.crsh.shell.ShellProcessContext;
023    import org.crsh.shell.ShellResponse;
024    import org.crsh.text.Chunk;
025    import org.crsh.text.Style;
026    import org.crsh.text.Text;
027    
028    import java.io.IOException;
029    import java.util.concurrent.CountDownLatch;
030    import java.util.concurrent.atomic.AtomicReference;
031    
032    class 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 provide(Chunk element) throws IOException {
116        if (element instanceof Text) {
117          Text textChunk = (Text)element;
118          processor.writer.append(textChunk.getText());
119        } else if (element instanceof Style) {
120          try {
121            ((Style)element).writeAnsiTo(processor.writer);
122          }
123          catch (IOException ignore) {
124          }
125        } else {
126    
127    
128          // Clear screen
129          processor.writer.print("\033[2J");
130          processor.writer.print("\033[1;1H");
131        }
132      }
133    
134      public void flush() {
135        processor.writer.flush();
136      }
137    
138      public void end(ShellResponse response) {
139        try {
140          resp.set(response);
141          latch.countDown();
142        }
143        finally {
144          // Release screen if it wasn't done
145          releaseAlternateBuffer();
146        }
147      }
148    }