package fdl;

import java.nio.ByteBuffer;

public class MetaReply extends PSXReply {

	public int id;
	public TupleSpace ts;

	public MetaReply(int mode, int id,TupleSpace ts) {
		this.mode = mode;
		this.id = id;
		this.ts = ts;
		this.command = ByteBuffer.allocate(PSX.LINDA_HEADER_SIZE);
	}

	public MetaReply(int mode, int id, TupleSpace ts,PSXCallback callback) {
		this(mode,id,ts);
		this.callback = callback;
	}

	public MetaReply(int mode, int id, TupleSpace ts,ByteBuffer data,
			PSXCallback callback) {
		this(mode,id,ts);
		this.data = data;
		this.callback = callback;
	}

	void checkTuple() {
		ByteBuffer data = ts.IN(id, mode, command);
		if (data!=null) {
			this.data = data;
			mode = PSX.PSX_ANSWER;
			if (callback!=null) callback.callback(data);
		}
	}
	
	public boolean ready() {
		switch(mode) {
		case PSX.PSX_IN:
		case PSX.PSX_RD:
			checkTuple();
			break;
		case PSX.PSX_CHECK:
			data = ts.check1(null, command);
			if (data!=null) {
				mode = PSX.PSX_ANSWER;
			}
			break;
		case PSX.PSX_OUT:
			ts.Out(null, command, data);
			return true;
		case PSX.PSX_UPDATE:
			// not implemented
			break;
		}
		return mode==PSX.PSX_ANSWER;
	}

}