ingo@2063: package de.intevation.flys.artifacts.model;
ingo@2063: 
ingo@2063: import net.sf.ehcache.Cache;
ingo@2063: import net.sf.ehcache.Element;
ingo@2063: 
ingo@2063: import org.apache.log4j.Logger;
ingo@2063: 
ingo@2063: import de.intevation.flys.model.Annotation;
ingo@2063: import de.intevation.flys.model.Position;
sascha@2127: import de.intevation.flys.model.Range;
ingo@2063: 
ingo@2063: import de.intevation.flys.artifacts.cache.CacheFactory;
ingo@2063: import de.intevation.flys.artifacts.model.AnnotationsFactory;
ingo@2063: 
sascha@2127: import java.util.Map;
sascha@2127: import java.util.TreeMap;
sascha@2127: import java.util.Comparator;
sascha@2127: import java.util.Iterator;
sascha@2127: 
sascha@2127: import java.io.Serializable;
sascha@2127: 
ingo@2063: 
ingo@2063: public class LocationProvider {
ingo@2063: 
sascha@2127:     public static final double EPSILON = 1e-5;
sascha@2127: 
sascha@2127:     public static class KmComparator
sascha@2127:     implements          Serializable, Comparator<Double>
sascha@2127:     {
sascha@2127:         @Override
sascha@2127:         public int compare(Double a, Double b) {
sascha@2127:             double diff = a - b;
sascha@2127:             if (diff < -EPSILON) return -1;
sascha@2127:             if (diff > +EPSILON) return +1;
sascha@2127:             return 0;
sascha@2127:         }
sascha@2127:     } // class KmComparator
sascha@2127: 
ingo@2063:     public static final String CACHE_KEY = "location-provider";
ingo@2063: 
sascha@2127:     public static final String PREFIX = "lp-";
sascha@2127: 
ingo@2063: 
ingo@2063:     private static final Logger logger =
ingo@2063:         Logger.getLogger(LocationProvider.class);
ingo@2063: 
ingo@2063: 
ingo@2063:     private LocationProvider() {
ingo@2063:     }
ingo@2063: 
sascha@2127:     public static String getLocation(String river, double km) {
ingo@2063: 
sascha@2127:         Double KM = Double.valueOf(km);
sascha@2127: 
sascha@2127:         return getKmMap(river, KM).get(KM);
ingo@2063:     }
ingo@2063: 
sascha@2127:     protected static Map<Double, String> getKmMap(String river, double km) {
ingo@2063: 
ingo@2063:         Cache cache = CacheFactory.getCache(CACHE_KEY);
ingo@2063: 
sascha@2127:         if (cache == null) {
sascha@2127:             return uncachedKmMap(river, km);
ingo@2063:         }
sascha@2127: 
sascha@2127:         String key = PREFIX + river;
sascha@2127: 
sascha@2127:         Element element = cache.get(key);
sascha@2127: 
sascha@2127:         if (element != null) {
sascha@2127:             return (Map<Double, String>)element.getValue();
ingo@2063:         }
sascha@2127: 
sascha@2127:         Map<Double, String> map = uncachedKmMap(river, null);
sascha@2127: 
sascha@2127:         cache.put(new Element(key, map));
sascha@2127: 
sascha@2127:         return map;
ingo@2063:     }
ingo@2063: 
sascha@2127:     protected static Map<Double, String> uncachedKmMap(
ingo@2063:         String river,
sascha@2127:         Double queryKm
ingo@2063:     ) {
sascha@2127:         Map<Double, String> map =
sascha@2127:             new TreeMap<Double, String>(new KmComparator());
sascha@2127:         
sascha@2127:         if (queryKm != null) {
sascha@2127:             Annotation annotation =
sascha@2127:                 AnnotationsFactory.getAnnotation(river, queryKm);
sascha@2127:             if (annotation != null) {
sascha@2127:                 map.put(queryKm, annotation.getPosition().getValue());
sascha@2127:             }
sascha@2127:             return map;
ingo@2063:         }
ingo@2063: 
sascha@2127:         for (Iterator<Annotation> iter =
sascha@2127:             AnnotationsFactory.getAnnotationsIterator(river);
sascha@2127:             iter.hasNext();
sascha@2127:         ) {
sascha@2127:             Annotation annotation = iter.next();
sascha@2127:             Position pos   = annotation.getPosition();
sascha@2127:             Range    range = annotation.getRange();
sascha@2127:             Double   km    = range.getA().doubleValue();
sascha@2127:             map.put(km, pos.getValue());
ingo@2063:         }
ingo@2063: 
sascha@2127:         return map;
ingo@2063:     }
ingo@2063: }
ingo@2063: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :