package explicit;

import java.util.BitSet;
import java.util.Objects;

/**
 * An AccumulationState contains a reference to an AccumulationTracker, 
 * a pointer to the latest restart and the numberOfTracks in the tracker.
 * It can optionally contain a BitSet marking the goodTracks.
 * 
 * @author Sascha Wunderlich
 *
 */
public class AccumulationState<Component> {
	protected final int trackerId;
	
	protected int lastRestartNr;
	protected int numberOfTracks;
	
	protected BitSet goodTracks;
	
	public AccumulationState(int trackerId, int lastRestartNr, int numberOfTracks, BitSet goodTracks) {
		this(trackerId, lastRestartNr, numberOfTracks);
		this.goodTracks = goodTracks;
	}
	
	public AccumulationState(int trackerId, int lastRestartNr, int numberOfTracks) {
		super();
		this.trackerId      = trackerId;
		this.lastRestartNr  = lastRestartNr;
		this.numberOfTracks = numberOfTracks;
		this.goodTracks     = new BitSet();
	}

	public int getTrackerId() {
		return trackerId;
	}
	
	public AccumulationTracker<Component> getTracker(StoragePool<AccumulationTracker<Component>> trackers) {
		return trackers.getById(trackerId);
	}
	
	public int getNextRestartNr() {
		return (lastRestartNr + 1) % numberOfTracks;
	}
	
	public boolean importantTrackIsGood() {
		return goodTracks.get(getNextRestartNr());
	}
	
	public BitSet getGoodTracks() {
		return goodTracks;
	}
	
	@Override
	public int hashCode() {
		return Objects.hash(goodTracks, lastRestartNr, numberOfTracks, trackerId);
	}

	@SuppressWarnings("rawtypes")
	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		AccumulationState other = (AccumulationState) obj;
		return Objects.equals(goodTracks, other.goodTracks) && lastRestartNr == other.lastRestartNr
				&& numberOfTracks == other.numberOfTracks && trackerId == other.trackerId;
	}

	@Override
	public String toString() {
		StringBuffer result = new StringBuffer();
		result.append("S");
		
		result.append(trackerId);
		
		return result.toString();
	}
	
}