/*
 * Copyright (C) 2009  Manish Pandya, [manish at meetamanish dot com]
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General protected
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General protected License for more details.
 *
 * You should have received a copy of the GNU Lesser General protected
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 * 
 */
package org.hooliguns.ninja.telnet.teensyninja.test;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import gnu.io.CommPort;
import gnu.io.CommPortIdentifier;
import gnu.io.SerialPort;

/**
 * A simple abstract class that provides test framework for TeensyNinja modded Ninja.
 * 
 * @author Manish Pandya (March 1 2009)
 * 
 */
public abstract class TestFrameworkForTeensyNinja {

  /**
   * max x pisition
   */
  protected static final int XMAX = 1800;

  /**
   * min x position
   */
  protected static final int XMIN = -1800;

  /**
   * max y position
   */
  protected static final int YMAX = 550;

  /**
   * min y position
   */
  protected static final int YMIN = -1200;

  /**
   * maximum velocity
   */
  protected static final int VMAX = 63;

  /**
   * minimum velocity
   */
  protected static final int VMIN = 0;

  /**
   * Should carry on? false will quit movement thread.
   */
  protected volatile boolean keepOn = true;

  /**
   * The terminal output stream that we print co-ordinates to.
   */
  protected OutputStream out = null;

  /**
   * The terminal input stream that we read response from.
   */
  protected InputStream in = null;

  /**
   * the shutdown hook
   */
  protected ShutdownHook shook = null;

  /**
   * The initialization method that sets up the comm port, adds shutdown hook and starts the random
   * movement thread. It uses gnu.io from RXTX.org but can readily converted to use javax.comm API.
   * 
   * @param portName
   *          the com port
   * @throws Exception
   *           when bad things happen
   */
  void connect(String portName, Runnable task) throws Exception {
    CommPortIdentifier portIdentifier = CommPortIdentifier
      .getPortIdentifier(portName);
    if (portIdentifier.isCurrentlyOwned()) {
      System.out.println("Error: Port is currently in use");
    }
    else {
      CommPort commPort = portIdentifier.open(this.getClass().getName(), 2000);
      if (commPort instanceof SerialPort) {
        SerialPort serialPort = (SerialPort) commPort;
        serialPort.setSerialPortParams(38400, SerialPort.DATABITS_8,
          SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);
        serialPort.setFlowControlMode(SerialPort.FLOWCONTROL_NONE);
        in = serialPort.getInputStream();
        out = serialPort.getOutputStream();
        shook = new ShutdownHook(this);
        (new Thread(task)).start();
      }
      else {
        System.out
          .println("Error: Only serial ports are handled by this example.");
      }
    }
  }

  /**
   * Method that checks if the Ninja unit is moving.
   * 
   * @param out
   *          the com port output stream where command for ninja is to be written
   * @param in
   *          the com port input stream where responce from ninja is to be read from
   * @return true if unit is moving, false otherwise
   */
  protected static boolean isInMotion(OutputStream out, InputStream in) {
    String status = new String(executeAndGetResponse("?", out, in));
    int pos = status.indexOf("IS_HALTED=");
    return '0' == status.charAt(pos + 10);
  }

  /**
   * A method that writes the randomly generated commands to the serial port and waits for about 6
   * seconds before returning.
   * 
   * @param command
   *          the command to be written
   * @param out
   *          the com port output stream where command for ninja is to be written
   * @param in
   *          the com port input stream where responce from ninja is to be read from
   */
  protected static byte[] executeAndGetResponse(String command,
    OutputStream out, InputStream in) {
    byte[] retval = new byte[0];
    try {
      if (out != null) {
        out.write(command.getBytes());
        // TeensyNinja's USB interface needs \r to declare that
        // data is available to read : usb_comm.c, recv_cmd()
        out.write("\r".getBytes());
        out.flush();
        // give some time to hardware to respond to the request
        try {
          Thread.sleep(100);
        }
        catch (InterruptedException e) {
          // wake up!
          e.printStackTrace();
        }
      }
      if (in != null) {
        int availCount = in.available();
        if (availCount > 0) {
          retval = new byte[availCount];
          int readcount = 0;
          while (readcount != availCount) {
            readcount += in.read(retval, readcount, availCount - readcount);
          }
        }
      }
    }
    catch (IOException e) {
      e.printStackTrace();
    }
    return retval;
  }

  /**
   * The shutdown hook that breaks the infinite loop of execution
   * 
   * @author Manish Pandya (March 1 2009)
   * 
   */
  protected class ShutdownHook extends Thread {
    /**
     * the test instance
     */
    TestFrameworkForTeensyNinja tftn;

    /**
     * A method that breaks the execution loop and centers the unit as last execution
     * 
     * @param rms
     *          the instance of the running test
     */
    protected ShutdownHook(TestFrameworkForTeensyNinja rms) {
      this.tftn = rms;
    }

    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Thread#run()
     */
    @Override
    public void run() {
      System.out.println("Shut down requested. Shutting down...");
      keepOn = false;
      String retstr = new String(executeAndGetResponse("c", tftn.out, tftn.in));
      System.out.println(retstr);
      while (isInMotion(tftn.out, tftn.in)) {
        try {
          Thread.sleep(1200);
          System.out.print('.');
        }
        catch (InterruptedException e) {
          // wake up!
        }
      }
    }
  }
}