content: package tim.prune.cmd;
  
  import tim.prune.DataSubscriber;
  import tim.prune.data.DataPoint;
  import tim.prune.data.TrackInfo;
  
  import java.util.ArrayList;
  
  /**
   * Remove the end of the track, cropping it to a smaller size
   */
  public class DeleteFinalRangeCmd extends Command
  {
  	private final int _numPointsToDelete;
  
  	public DeleteFinalRangeCmd(int inNumToDelete) {
  		this(null, inNumToDelete);
  	}
  
  	protected DeleteFinalRangeCmd(Command inParent, int inNumToDelete)
  	{
  		super(inParent);
  		_numPointsToDelete = inNumToDelete;
  	}
  
  	@Override
  	public int getUpdateFlags() {
  		return DataSubscriber.DATA_ADDED_OR_REMOVED;
  	}
  
  	@Override
  	protected boolean executeCommand(TrackInfo inInfo)
  	{
  		if (_numPointsToDelete < 0 || _numPointsToDelete > inInfo.getTrack().getNumPoints()) {
  			return false;
  		}
  		inInfo.getTrack().cropTo(inInfo.getTrack().getNumPoints() - _numPointsToDelete);
  		inInfo.getSelection().clearAll();
  		return true;
  	}
  
  	@Override
  	protected Command makeInverse(TrackInfo inInfo)
  	{
  		ArrayList<DataPoint> points = new ArrayList<>();
  		final int totalPoints = inInfo.getTrack().getNumPoints();
  		final int startIdx = totalPoints - _numPointsToDelete;
  		for (int i=startIdx; i<totalPoints; i++) {
  			points.add(inInfo.getTrack().getPoint(i));
  		}
  		return new AppendRangeCmd(this, points);
  	}
  }
  