package org.eclipse.stem.loggers.imagewriter.logger;

import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import org.apache.commons.collections.map.ReferenceMap;
import org.eclipse.stem.core.common.Identifiable;
import org.eclipse.stem.core.graph.NodeLabel;
import org.eclipse.stem.definitions.adapters.spatial.geo.LatLong;
import org.eclipse.stem.definitions.adapters.spatial.geo.LatLongProvider;
import org.eclipse.stem.definitions.adapters.spatial.geo.LatLongProviderAdapter;
import org.eclipse.stem.definitions.adapters.spatial.geo.LatLongProviderAdapterFactory;
import org.eclipse.stem.loggers.imagewriter.logger.projections.IMapProjection;

public class PolygonHandler 
{

	
	private static final Map<Class<? extends IMapProjection>, Map> cachedPolygons = 
			new HashMap<Class<? extends IMapProjection>, Map>();
	
	
	public static class ProjectedPolygons
	{
		public Identifiable identifiable;
		public List<ProjectedPolygon> polygons = new LinkedList<ProjectedPolygon>();
		
		public ProjectedPolygons()
		{
			
		}
	}
	
	public static class ProjectedPolygon
	{
		public double[] points;
		
		public ProjectedPolygon(int vertexCount)
		{
			points = new double[vertexCount*2+1];
		}
	}
	
	
	private static final ProjectedPolygons getProjectedPolygons(IMapProjection projection, Identifiable identifiable, LatLong points)
	{

		ProjectedPolygons polygons = new ProjectedPolygons();
		polygons.identifiable = identifiable;
		if (points != null) {
			for (LatLong.Segment segment : points.getSegments()) {
				if (segment.size() > 0) {
					ProjectedPolygon poly = new ProjectedPolygon(segment.size());
					polygons.polygons.add(poly);
					int vertexCount = segment.size();
					for (int i = 0; i < vertexCount; i++) {
						double[] pt = projection.project(segment.latitude(i), segment.longitude(i));
	
						poly.points[i*2] = pt[0];
						poly.points[i*2+1] = pt[1];
					}
				}
			}
		}
		
		if (polygons.polygons.size() < 1) {
			polygons = null;
		}
		
		return polygons;
	}
	
	
	public static ProjectedPolygons getPolygonsForProjection(IMapProjection projection, NodeLabel label)
	{
		
		Map projectionCache = cachedPolygons.get(projection.getClass());
		if (projectionCache == null) {
			// create a new map entry for the projection
			projectionCache = new ReferenceMap(ReferenceMap.SOFT, ReferenceMap.SOFT);
			cachedPolygons.put(projection.getClass(), projectionCache);
		}
		
		ProjectedPolygons retVal = null;
		
		Object obj = projectionCache.get(label.getIdentifiable().getURI());
		if (obj != null) {
			System.out.println("LoadFromCache "+ label.getIdentifiable().getURI());
			
			// We have an existing polygon set in cache.  return
			retVal = (ProjectedPolygons)obj;
		} else {
			
			System.err.println("LoadFromFile "+ label.getIdentifiable().getURI());
			
			// The polygon is not cached.  We need to acquire the lat/lng data, project, and cache 
			LatLongProviderAdapter latLongProvider = (LatLongProviderAdapter)LatLongProviderAdapterFactory.INSTANCE.adapt(label, LatLongProvider.class);

			latLongProvider.setTarget(label.getIdentifiable());
			LatLong latLong = latLongProvider.getLatLong();
			
			retVal = getProjectedPolygons(projection, label.getIdentifiable(), latLong);
			if (retVal != null) {
				projectionCache.put(label.getIdentifiable().getURI(), retVal);
			}
		}
		
		return retVal;


	}
	
	
}