// ComPort.java
//
// Copyright (C) 1998 Henrik Bjorkman. This is free software you 
// may use, copy and distribute this program freely. But you
// must do it on your own risk. No responsibilities taken and
// all rights reserved.
//
// This class is an interface between a java program and a serial 
// port. It works on Windows NT and it should work on most unix
// systems but it does not work on Win95.
//
//
// Credits
//
// SUNs jdk 1.1.5 was used when developing this program.
//
// I had help by looking at how these things where done in a program 
// called "Elgaard Positioning System" when creating this program.
//
//
// History
//
// 1998-05-20 Created by Henrik Bjorkman
// 1998-06-02 Added package. /Henrik
//

package se.beod.henrik.nav;
import java.io.*;

class ComPort
{
  String portName;
  File file;  
  FileInputStream in;

  static void error(String s)
  {
    System.err.println("ComPort: " + s);
  }

  static void debug(String s)
  {
    //System.out.println("ComPort: " + s);
  }

  public ComPort(String port_name) 
  {
    debug("serialOpen");
    try 
    { 
      String init=null;

      debug("system "+System.getProperty("os.name"));

      if (System.getProperty("os.name").toUpperCase().indexOf("WINDOWS")>=0) 
      {
        debug("dos");
        portName="com1";
        if ((System.getProperty("os.name").toUpperCase().indexOf("WINDOWS NT")>=0))
        {
          init = "MODE.COM " + portName + " 4800,N,8,1 ";
        }
        else
        {
          error("Windows 95 is a bag of shit! Set baudrate manually to 4800,n,8,1");
        }
      } 
      else 
      {
        debug("unix");
        portName="/dev/cua0";
        init = "/bin/sh " + "-c " + "stty 4800 pass8 -parenb  -inlcr  ixany -ixon < " + portName;
      }

      if (init!=null)
      {
        Process pid=Runtime.getRuntime().exec(init);

        InputStream in = new DataInputStream(pid.getInputStream());

        while (true) 
        {
          int ch=1;
	  ch = in.read();
          if (ch<0) break;
          System.out.print((char)ch);
        }
      }

      file = new File(portName);
      in = new FileInputStream(file);

    } 
    catch(IOException e) 
    {
      error("IOException " + e);
    } 
    catch(SecurityException e) 
    {
      error("SecurityException "+ e);
    }
  }


  String readLine()
  {
    StringBuffer line=new StringBuffer();

    try 
    {
      while(true)
      {
        int ch;
        ch=in.read();
        if ((ch=='\r') || (ch=='\n'))
        {
          break;
        }
        else if (ch>0)
        {
          line.append((char)ch);
        }
        else
        {
          synchronized (this) {try {this.wait(50);}  catch (InterruptedException e) {;}}
        }
      }
    }
    catch( IOException e ) 
    {
      error("read " + e );
    }

    debug(line.toString());
    return(line.toString());
  }

  void serialClose() 
  {
    debug("serialClose");
    try 
    {
      if (in != null)
      {
        debug("close");
	in.close();
	in=null;
      }
    }
    catch( IOException e ) 
    {
      error("close " + e );
    }  
  }
}