/*
 * Copyright (c) 2003, KNOPFLERFISH project
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials
 *   provided with the distribution.
 *
 * - Neither the name of the KNOPFLERFISH project nor the names of its
 *   contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.knopflerfish.bundle.consoletelnet;

import java.io.Writer;
import java.io.PrintWriter;
import java.io.CharArrayWriter;
import java.io.OutputStream;
import java.io.IOException;

/**
 ** This extension of a PrintWriter makes the following
 ** translations on data in the output stream
 **
 ** CR LF -> no change
 ** CR <n>, when n != LF -> CR NULL <n>
 ** <n> LF -> <n> CR LF
 **
 ** All characters in the output buffer are 
 ** anded with a mask from the session.
 ** This mask is either 0x7F (7 bit) or 0xFF (8 bit)
 **
 ** It also has a clear method to empty the output buffer
 ** and a writeCommand method to send telnet commands.
 **
 */

public class TelnetPrintWriter extends PrintWriter {
  private TelnetStateMachine tsm;
  private TelnetSession ts;
  private CharArrayWriter caw;		// Intermediate array writer
  private PrintWriter pw2;		// Private PrintWriter
  private boolean prevWasCR = false;	

  public TelnetPrintWriter (OutputStream os, TelnetStateMachine tsm, TelnetSession ts) {
    super (os);
    this.tsm = tsm;
    this.ts = ts;
    Writer w1 = super.out;		// get the underlaying writer
    caw = new CharArrayWriter(); 	// intermediate array writer
    super.out = caw;			// replace underlying Writer with a CharArrayWriter
    pw2 = new PrintWriter (w1);		// a private PrintWriter
  }
  
  /**
   ** Override flusg and close methods,
   */

  public void flush () {
    caw.flush();
    pribuf();
    pw2.flush();
  }
 
  public void close () {
    flush();
    caw.close();
    pw2.close();
  }

  /**
   ** Override all println methods, add CRLF as end of line 
   */

  public synchronized void println() {
    // super.println();
    write(TCC.CR);
    write(TCC.LF);
    flush();
  } 

  public synchronized void println(boolean b) {
    super.print(b);
    this.println();
  }

  public synchronized void println(char c) {
    synchronized (this) {
    super.print(c);
    this.println();
    }
  }

  public synchronized void println(int i) {
    super.print(i);
    this.println();
  }

  public synchronized void println(long l) {
    super.print(l);
    this.println();
  }

  public synchronized void println(float f) {
    super.print(f);
    this.println();
  }

  public synchronized void println(double d) {
    super.print(d);
    this.println();
  }

  public synchronized void println(char[] c) {
    super.print(c);
    this.println();
  }

  public synchronized void println(String s) {
    synchronized (this) {
    super.print(s);
    this.println();
    }
  }

  public synchronized void println(Object o) {
    super.print(o);
    this.println();
  }
  
  /**
   ** Override all write methods, write to internal buffer first
   */

  public synchronized void write(char [] buf) {
    caw.write(buf,0, buf.length);
  }

  public synchronized void write (char [] buf, int off, int len) {
    caw.write(buf, off, len);
  }

  public synchronized void write(String s) {
    synchronized (this) {
      try {
        caw.write(s);
      }
      catch (IOException iox ) {
        System.out.println ("Exception in TelnetPrintWriter write (String) " + iox.toString());
      }
    }
  }

  public synchronized void write(int c) {
    caw.write(c);
  }

  public synchronized void write(String s, int off, int len) {
    caw.write(s, off, len);
  }

  /**
   ** Scan the output buffer for CR<n> where n != LF, 
   ** which is translated it to CR NULL n
   */

  private synchronized void pribuf() {
    char [] buf =  caw.toCharArray();
    caw.reset();
    char mask = ts.getMask();

    for (int i = 0; i < buf.length; i++) {
      if (prevWasCR == true) {
        if (buf[i] != TCC.LF_char) { // add a NULL
          pw2.write (TCC.NULL_char);
          pw2.write (buf[i] & mask);
        } else {
          pw2.write (buf[i] & mask);
        }
      } else {
        if (buf[i] == TCC.LF_char) { // a single LF -> CRLF
          pw2.write (TCC.CR_char);
          pw2.write (TCC.LF_char);
        } else {
          pw2.write (buf[i] & mask);
        }
      }
      prevWasCR = (buf[i] == TCC.CR_char) ? true : false;
    }
    // pw2.flush();
  }

  public synchronized void reset() {
    caw.reset();
  }

  /**
   ** Write a telnet command in the output stream.
   **
   ** @parameter tc, command string to write
   */

  public synchronized void writeCommand(String tc) {
    if (tc != null) {
      pw2.print(tc);
      pw2.flush();
    }
  }
}