/**
 *
 * @author sherlock
 */
public class NxtMessage
{
	final static public int INCOMING = 0;
	final static public int REQUEST = 1;
	final static public byte[] RESPONSE_MSG = new byte[]{ 0x02, 0x09, 0x00 };
	int type;
	int mailbox;
	String message;
	boolean responseNeeded;
	
	
	public class UnknownMessage extends Exception{} 
	
	int getType ()
	{
		return type;
	}
    
	int getMailbox ()
	{
		return mailbox;
	}
    
	String getMessage ()
    	{
		return message;
	}
	boolean getResponseNeeded ()
	{
		return responseNeeded;
	}
    

	public NxtMessage (int _type, int _mailbox, String _message,boolean _responseNeeded)
	{
		
		type = _type;
		mailbox = _mailbox;
		message = _message;
		responseNeeded = _responseNeeded;
	} 

	public NxtMessage (byte[]cmd) throws UnknownMessage 
	{
		
		if ((cmd[0] & 0x7F) == 0 && cmd[1] == 0x09)
		{
			type = INCOMING;	
			mailbox = (int) cmd[3];
			message = new String (cmd, 4, (int) cmd[3] - 1);
			responseNeeded = cmd[0] == 0x00;
		}
		else if ((cmd[0] & 0x7F) == 0x02 && cmd[1] == 0x13)
		{
			type = REQUEST;	
			message = "";
			mailbox = (int) cmd[2];		
		}
		else
			throw new UnknownMessage ();
	}
    

	public String toString ()
	{
		
		String s = (type == INCOMING ? "INCOMING" : "REQUEST") +(responseNeeded ? " (R)" : "") + ": " + mailbox + ", " +"'" + message + "'" + ", " + message.length ();
		return s;
	}
    

	public byte[]pack ()
	{
		byte[]cmd = new byte[80];
		cmd[2] = (byte) 0x80;
		cmd[3] = (byte) 0x09;
		cmd[4] = (byte) mailbox;
		String msg = message + "\0";
		cmd[5] = (byte) (msg.length () & 0xff);

		for (int i = 0; i < msg.length (); i++)
			cmd[6 + i] = (byte) msg.charAt (i);
	
		cmd[0] = (byte) ((cmd.length - 2) & 0xFF);
		cmd[1] = (byte) ((cmd.length - 2) >> 8);

		return cmd;
    
	}

}