package org.apache.tuscany.sca.binding.erlang.impl;

import com.ericsson.otp.erlang.OtpErlangAtom;
import com.ericsson.otp.erlang.OtpErlangList;
import com.ericsson.otp.erlang.OtpErlangObject;
import com.ericsson.otp.erlang.OtpErlangPid;
import com.ericsson.otp.erlang.OtpErlangRef;
import com.ericsson.otp.erlang.OtpErlangTuple;

public class MessageHelper {

	private static String ATOM_BADRPC = "badrpc";
	private static String ATOM_EXIT = "EXIT";
	private static String ATOM_UNDEF = "undef";

	public static OtpErlangObject functionUndefMessage(String module, String function, OtpErlangList args, String tuscanyMsg) {
		OtpErlangObject[] args4 = new OtpErlangObject[3];
		args4[0] = new OtpErlangAtom(module);
		args4[1] = new OtpErlangAtom(function);
		args4[2] = args;
		
		OtpErlangObject[] args3 = new OtpErlangObject[2];
		args3[0] = new OtpErlangTuple(args4);
		args3[1] = new OtpErlangAtom(tuscanyMsg);
		
		OtpErlangObject[] args2 = new OtpErlangObject[2];
		args2[0] = new OtpErlangAtom(ATOM_UNDEF);
		args2[1] = new OtpErlangList(args3);
		
		OtpErlangObject[] args1 = new OtpErlangObject[2];
		args1[0] = new OtpErlangAtom(ATOM_EXIT);
		args1[1] = new OtpErlangTuple(args2);
		
 		OtpErlangTuple result = new OtpErlangTuple(args1);
		return result;
	}
	
	public static boolean isfunctionUndefMessage(OtpErlangObject msg) {
		if (msg.getClass().equals(OtpErlangTuple.class)) {
			OtpErlangTuple tupleMsg = (OtpErlangTuple) msg;
			if (tupleMsg.arity() == 2
					&& tupleMsg.elementAt(0).getClass().equals(
							OtpErlangAtom.class)
					&& tupleMsg.elementAt(1).getClass().equals(
							OtpErlangTuple.class)
					&& ((OtpErlangAtom) tupleMsg.elementAt(0)).atomValue()
							.equals(ATOM_BADRPC)) {
				OtpErlangTuple badrpcTuple = (OtpErlangTuple) tupleMsg
						.elementAt(1);
				if (badrpcTuple.arity() == 2
						&& badrpcTuple.elementAt(0).getClass().equals(
								OtpErlangAtom.class)
						&& badrpcTuple.elementAt(1).getClass().equals(
								OtpErlangTuple.class)
						&& ((OtpErlangAtom) badrpcTuple.elementAt(0))
								.atomValue().equals(ATOM_EXIT)) {
					OtpErlangTuple exitTuple = (OtpErlangTuple) badrpcTuple
							.elementAt(1);
					if (exitTuple.arity() == 2
							&& exitTuple.elementAt(0).getClass().equals(
									OtpErlangAtom.class)
							&& ((OtpErlangAtom) exitTuple.elementAt(0))
									.atomValue().equals(ATOM_UNDEF)) {
						return true;
					}
				}

			}
		}
		return false;
	}
	
	public static OtpErlangTuple rpcMessage(OtpErlangPid senderPid, OtpErlangRef ref, String module, String function, OtpErlangList args) {
		OtpErlangObject[] args3 = new OtpErlangObject[5];
		args3[0] = new OtpErlangAtom("call");
		args3[1] = new OtpErlangAtom(module);
		args3[2] = new OtpErlangAtom(function);
		args3[3] = args;
		args3[4] = senderPid;
		
		OtpErlangObject[] args2 = new OtpErlangObject[2];
		args2[0] = senderPid;
		args2[1] = ref;
		
		OtpErlangObject[] args1 = new OtpErlangObject[3];
		args1[0] = new OtpErlangAtom("$gen_call");
		args1[1] = new OtpErlangTuple(args2);
		args1[2] = new OtpErlangTuple(args3);
		
		OtpErlangTuple result = new OtpErlangTuple(args1);
		return result;
	}
}