tom@8858: /* Copyright (C) 2011, 2012, 2013 by Bundesanstalt für Gewässerkunde
tom@8858:  * Software engineering by Intevation GmbH
tom@8858:  *
tom@8858:  * This file is Free Software under the GNU AGPL (>=v3)
tom@8858:  * and comes with ABSOLUTELY NO WARRANTY! Check out the
tom@8858:  * documentation coming with Dive4Elements River for details.
tom@8858:  */
tom@8858: 
rrenkert@8251: package org.dive4elements.river.exports.injector;
rrenkert@8251: 
rrenkert@8251: import org.apache.log4j.Logger;
rrenkert@8251: import org.dive4elements.artifacts.Artifact;
rrenkert@8251: import org.dive4elements.artifacts.ArtifactNamespaceContext;
rrenkert@8251: import org.dive4elements.artifacts.CallContext;
rrenkert@8251: import org.dive4elements.artifacts.ContextInjector;
rrenkert@8251: import org.dive4elements.artifacts.common.utils.XMLUtils;
rrenkert@8251: import org.dive4elements.river.artifacts.D4EArtifact;
rrenkert@8251: import org.dive4elements.river.artifacts.access.RangeAccess;
rrenkert@8251: import org.w3c.dom.Document;
rrenkert@8251: import org.w3c.dom.Element;
rrenkert@8251: 
rrenkert@8251: import static org.dive4elements.river.exports.injector.InjectorConstants.CURRENT_KM;
rrenkert@8251: 
rrenkert@8251: 
tom@8349: public class KmFromRequestInjector
rrenkert@8251: implements ContextInjector
rrenkert@8251: {
tom@8856:     private static final Logger log = Logger.getLogger(
tom@8856:         KmFromRequestInjector.class);
rrenkert@8251: 
rrenkert@8251:     public static final String XPATH_CHART_CURRENTKM =
rrenkert@8251:         "/art:action/art:attributes/art:currentKm/@art:km";
rrenkert@8251:     @Override
rrenkert@8251:     public void setup(Element cfg) {
rrenkert@8251: 
rrenkert@8251:     }
rrenkert@8251: 
rrenkert@8251:     @Override
rrenkert@8251:     public void injectContext(
rrenkert@8251:         CallContext ctx,
rrenkert@8251:         Artifact artifact,
tom@8367:         Document request
tom@8367:     ) {
tom@8367:         if (ctx.getContextValue(CURRENT_KM) instanceof Number) {
tom@8367:             return;
tom@8367:         }
tom@8367: 
rrenkert@8251:         Double km = getCurrentKmFromRequest(request);
rrenkert@8326:         if (Double.isNaN(km)) {
rrenkert@8251:             RangeAccess access = new RangeAccess((D4EArtifact)artifact);
rrenkert@8251:             km = access.getFrom();
rrenkert@8251:         }
rrenkert@8251:         ctx.putContextValue(CURRENT_KM, km);
rrenkert@8251:     }
rrenkert@8251: 
rrenkert@8251:     private Double getCurrentKmFromRequest(Document request) {
rrenkert@8251: 
rrenkert@8251:         String km = XMLUtils.xpathString(
rrenkert@8251:             request,
rrenkert@8251:             XPATH_CHART_CURRENTKM,
rrenkert@8251:             ArtifactNamespaceContext.INSTANCE);
rrenkert@8251: 
rrenkert@8251:         if (km == null) {
rrenkert@8251:             return Double.NaN;
rrenkert@8251:         }
rrenkert@8251: 
rrenkert@8251:         try {
rrenkert@8251:             return Double.valueOf(km);
rrenkert@8251:         }
rrenkert@8251:         catch (NumberFormatException nfe) {
rrenkert@8251:             return Double.NaN;
rrenkert@8251:         }
rrenkert@8251:     }
rrenkert@8251: }