package ie.dcu.apps.ist;

import ie.dcu.segment.*;

import java.util.*;

/**
 * Registry for segmenters.
 * 
 * @author Kevin McGuinness
 */
public class SegmenterRegistry implements Iterable<Segmenter> {
	private static final String DEFAULT_SEGMENTER_NAME = "IgcSegmenter";
	private static SegmenterRegistry instance;
	private final Set<Segmenter> segmenters;
	
	private SegmenterRegistry() {
		segmenters = new LinkedHashSet<Segmenter>();
		init();
	}
	
	
	private void init() {
		// OutlineSegmenter is not very useful
		// add(new OutlineSegmenter());
		
		// Geodesic Active Contours is too sensitive to parameters
		// for general use on natural images.
		// add(new SeededGacSegmenter());
		
		//add(new SrgSegmenter());
		//add(new IgcSegmenter());
		//add(new BptSegmenter());
		//add(new SioxSegmenter());
		//add(new SpatiogramSegmenter());
	}


	public static SegmenterRegistry getInstance() {
		if (instance == null) {
			instance = new SegmenterRegistry();
		}
		return instance;
	}
	
	
	public Segmenter find(String name) {
		for (Segmenter s : segmenters) {
			
			// Check name
			String ename = s.getName();
			if (ename.equals(name)) {
				return s;
			}
			
			// Check class name
			String cname = s.getClass().getName();
			if (cname.equals(name)) {
				return s;
			}
			
			// Check simple name
			String sname = s.getClass().getSimpleName();
			if (sname.equals(name)) {
				return s;
			}
		}
		
		return null;
	}
	
	
	public boolean isDefault(Segmenter s) {
		if (s != null) {
			if (segmenters.size() == 1 && segmenters.contains(s)) {
				return true;
			}
			return s.getClass().getSimpleName().equals(DEFAULT_SEGMENTER_NAME);
		}
		return false;
	}
	
	
	public Segmenter getDefault() {
		for (Segmenter s : segmenters) {
			if (isDefault(s)) {
				return s;
			}
		}
		return null;
	}
	
	
	public void add(Segmenter segmenter) {
		segmenters.add(segmenter);
	}
	
	
	public Set<Segmenter> segmenters() {
		return Collections.unmodifiableSet(segmenters);
	}


	public Iterator<Segmenter> iterator() {
		return segmenters.iterator();
	}
}