/** Data structure representing a single monitoring command.
 * <p>
 * This version only supports ongoing monitoring, not recurring monitoring. 
 * To perform one-time-only monitoring, set startTime = stopTime.
 *
 * @version 0.2
 * @author Glenn Matthews
 */
public class MonitorNode implements Comparable<MonitorNode> {

/** The simulation time at which this monitoring command becomes relevant. */
double startTime;

/** The simulation time after which this monitoring command becomes irrelevant
 * and should be discarded. */
double stopTime;

/** The identifier of the variable to be monitored. */
String targetVar;

/** The identifier of the monitoring app that asked for this information. */
int clientID;

/** Basic constructor. */
public MonitorNode(double start, double stop, String target, int source)
{
	startTime = start;
	stopTime = stop;
	targetVar = target;
	clientID = source;

//added by yin for debugging only
 System.out.println("\nin MonitorNode constructor 1: " );
 System.out.println("client id: " + clientID);
 System.out.println("targetVar: " + targetVar);
 System.out.println("startTime: " + startTime);
 System.out.println("stopTime: " + stopTime);

} //constructor

/** Simpler constructor that is more future-compatible - parses the given
 * String to determine all parameters except {@link #clientID}.
 * @param source Numeric identifier of the monitoring app making this request
 * @param attribs String of the format "{@link #targetVar}\r\n{@link 
 * #startTime}\r\n{@link #stopTime}"
 */
public MonitorNode(int source, String attribs)
{
	clientID = source;
	String[] s = attribs.split("\r\n");
	targetVar = s[0];
	startTime = Double.parseDouble(s[1]);
	stopTime = Double.parseDouble(s[2]);

//added by yin for debugging only
 System.out.println("\nin MonitorNode constructor 2: " );
 System.out.println("client id: " + clientID);
 System.out.println("targetVar: " + targetVar);
 System.out.println("startTime: " + startTime);
 System.out.println("stopTime: " + stopTime);

} //constructor

/* GETTERS */
public double getStartTime() { return startTime; }
public double getStopTime() { return stopTime; }
public String getTargetVar() { return targetVar; }
public int getClientID() { return clientID; }

/* SETTERS */
public void setStartTime(double t) { startTime = t; }
public void setStopTime(double t) { stopTime = t; }
public void setTargetVar(String s) { targetVar = s; }
public void setClientID(int i) { clientID = i; }

/** Compares two MonitorNodes. Ordering is as follows:
 * <ol><li>by {@link #startTime}
 * <li>by {@link #stopTime}
 * <li>by {@link #targetVar}
 * <li>by {@link #clientID}
 * </ol>
 */
public int compareTo(MonitorNode o)
{
	if (startTime < o.startTime)
		return -1;
	else if (startTime > o.startTime)
		return 1;
	else {
		if (stopTime < o.stopTime)
			return -1;
		else if (stopTime > o.stopTime)
			return 1;
		else {
			int i = targetVar.compareTo(o.targetVar);
			if (i != 0)
				return i;
			if (clientID < o.clientID)
				return -1;
			else if (clientID > o.clientID)
				return 1;
			else
				return 0;
		}
	}
} //compareTo

/** Checks for equality. A MonitorNode is never equal to an Object that is not
 * another MonitorNode; two MonitorNodes are equal if they have equal startTime,
 * stopTime, targetVar, and clientID. */
public boolean equals(Object o)
{
	if (!(o instanceof MonitorNode))
		return false;
	MonitorNode m = (MonitorNode)o;
	return (startTime == m.startTime &&
		stopTime == m.stopTime &&
		targetVar.equals(m.targetVar) &&
		clientID == m.clientID);
} //equals

} //MonitorNode