/**
 * $OpenXM: OpenXM/src/OpenMath/OMproxy.java,v 1.4 1999/11/04 18:21:42 tam Exp $
 */

import JP.ac.kobe_u.math.tam.OpenXM.*;
import java.util.Stack;
import java.io.*;

class OMproxy implements Runnable{
  private OpenXM ox;
  private Stack stack = new Stack();
  private boolean debug = true;

  public OMproxy(String host,int ControlPort,int DataPort) throws IOException{
    ox = new OpenXM(this,host,ControlPort,DataPort);
  }

  public void run(){
    OM2OXM P = new OM2OXM();

    try{
      while(true){
	synchronized(ox){
	  int ox_tag = ox.receiveOXtag();

	  switch(ox_tag){
	  case OpenXM.OX_COMMAND:
	    StackMachine(ox.receiveSM());
	    break;

	  case OpenXM.OX_DATA:
	    stack.push(ox.receiveCMO());
	    debug("push: "+ stack.peek());
	    break;
	  }
	}
      }
    }catch(java.io.IOException e){
      System.err.println(e.getMessage());
      e.printStackTrace();
    }

    System.out.println("breaking...");
  }

  public void stop(){
    System.out.println("OMproxy Stoping...");
    synchronized(ox){
      //this.stop();
      while(!stack.empty()){
	stack.pop();
      }
      System.out.println("OMproxy Stopped");
    }
  }

  private void SM_popCMO() throws java.io.IOException{
    if(stack.empty()){
      ox.send(new CMO_NULL());
    }else{
      ox.send(stack.pop());
    }
  }

  private void SM_executeFunction() throws java.io.IOException{
    String function_name;
    CMO[] argv;
    int argc = 1;

    if(!(stack.peek() instanceof CMO_STRING)){
      stack.push(new CMO_ERROR2());
      return;
    }
    function_name = ((CMO_STRING)stack.pop()).getString();
    //argc = ((CMO_INT32)stack.pop()).intValue();
    argv = new CMO[argc];
    for(int i=0;i<argc;i++){
      argv[i] = (CMO)stack.pop();
    }

    if(argc != 1){
      stack.push(new CMO_ERROR2());
      return;
    }

    if(function_name.equals("OMXML2CMO")){
      stack.push(OMXML2CMO(argv[0]));
      return;
    }else if(function_name.equals("CMO2OMXML")){
      stack.push(CMO2OMXML(argv[0]));
      return;
    }

    stack.push(new CMO_ERROR2());
    return;
  }

  private void StackMachine(SM mesg) throws java.io.IOException{
    debug("receive: "+mesg);

    switch(mesg.getCode()){
    case SM.SM_popCMO:
      SM_popCMO();
      break;

    case SM.SM_executeFunction:
      SM_executeFunction();
      break;

    default:
      System.out.println("received "+ mesg);
    }
  }

  private CMO CMO2OMXML(CMO obj){
    String str = OM2OXM.CMO2OM(obj);

    return new CMO_STRING(str);
  }

  private CMO OMXML2CMO(CMO obj){
    OM2OXM trans = new OM2OXM();
    //StringBufferInputStream stream;
    ByteArrayInputStream stream;
    CMO ret;

    debug("OMXML2CMO called: "+ret);

    if(obj instanceof CMO_STRING){
      return new CMO_ERROR2();
    }

    try{
      stream = new ByteArrayInputStream(((CMO_STRING)obj).getString().getBytes());
      ret = trans.parse(stream);
    }catch(IOException e){
      return new CMO_ERROR2(new CMO_STRING(e.toString()));
    }

    debug("push: "+ret);
    return ret;
  }

  private void debug(String str){
    if(debug){
      System.out.println(str);
    }
  }

  private static String usage(){
    String ret = "";

    ret += "usage\t: java OMproxy [options]\n";
    ret += "options\t:\n";
    ret += "\t -h \t show this message\n";
    ret += "\t -host hostname \t (default localhost)\n";
    ret += "\t -data port \t (default 1300)\n";
    ret += "\t -control port \t (default 1200)\n";

    return ret;
  }

  public static void main(String argv[]){
    String host = "localhost";
    int DataPort = 1300, ControlPort = 1200;

    for(int i=0;i<argv.length;i++){
      if(argv[i].equals("-h")){
	System.out.print(usage());
	System.exit(0);
      }else if(argv[i].equals("-host")){
	host = argv[++i];
      }else if(argv[i].equals("-data")){
	DataPort = Integer.valueOf(argv[++i]).intValue();
      }else if(argv[i].equals("-control")){
	ControlPort = Integer.valueOf(argv[++i]).intValue();
      }else{
	System.err.println("unknown option : "+ argv[i]);
	System.err.print(usage());
	System.exit(1);
      }
    }

    System.out.println("host(ctrl,data): "+ host
		       +"("+ ControlPort +","+ DataPort +")");

    try{
      new OMproxy(host,ControlPort,DataPort);
      System.out.println("connected.");
    }catch(IOException e){
      System.err.println("Error occured: "+ e);
      System.err.println(e.getLocalizedMessage());
      System.err.println(e.getMessage());
    }
  }
}