ingo@535: package de.intevation.flys.client.server;
ingo@535: 
ingo@535: import java.io.InputStream;
ingo@535: import java.io.IOException;
ingo@535: 
ingo@535: import javax.xml.xpath.XPathConstants;
ingo@535: 
ingo@535: import org.w3c.dom.Document;
ingo@535: import org.w3c.dom.Element;
ingo@535: import org.w3c.dom.Node;
ingo@535: 
ingo@535: import com.google.gwt.user.server.rpc.RemoteServiceServlet;
ingo@535: 
ingo@535: import de.intevation.artifacts.common.ArtifactNamespaceContext;
ingo@535: import de.intevation.artifacts.common.utils.ClientProtocolUtils;
ingo@535: import de.intevation.artifacts.common.utils.XMLUtils;
ingo@535: import de.intevation.artifacts.common.utils.XMLUtils.ElementCreator;
ingo@535: 
ingo@535: import de.intevation.artifacts.httpclient.http.HttpClient;
ingo@535: import de.intevation.artifacts.httpclient.http.HttpClientImpl;
ingo@535: 
ingo@535: import de.intevation.flys.client.shared.Transform2D;
ingo@535: import de.intevation.flys.client.shared.exceptions.ServerException;
ingo@535: import de.intevation.flys.client.shared.model.Collection;
ingo@535: 
ingo@535: import de.intevation.flys.client.client.services.ChartInfoService;
ingo@535: 
ingo@535: 
ingo@535: /**
ingo@535:  * This service fetches a document that contains meta information for a specific
ingo@535:  * chart.
ingo@535:  *
ingo@535:  * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
ingo@535:  */
ingo@535: public class ChartInfoServiceImpl
ingo@535: extends      RemoteServiceServlet
ingo@535: implements   ChartInfoService
ingo@535: {
ingo@535:     public static final String XPATH_TRANSFORM_MATRIX =
ingo@535:         "/art:chartinfo/art:transformation-matrix";
ingo@535: 
ingo@535:     public static final String EXCEPTION_STRING = "error_chart_info_service";
ingo@535: 
ingo@535: 
ingo@535:     public Transform2D getChartInfo(
ingo@535:         Collection collection,
ingo@535:         String     url,
ingo@535:         String     locale,
ingo@535:         String     type,
ingo@535:         int        width,
ingo@535:         int        height)
ingo@535:     throws ServerException
ingo@535:     {
ingo@535:         System.out.println("ChartInfoServiceImpl.getChartInfo");
ingo@535: 
ingo@535:         Document request = ClientProtocolUtils.newOutCollectionDocument(
ingo@535:                 collection.identifier(),
ingo@535:                 type,
ingo@535:                 type,
ingo@535:                 getChartAttributes(width, height));
ingo@535: 
ingo@535:         try {
ingo@535:             HttpClient client = new HttpClientImpl(url, locale);
ingo@535:             InputStream in    = client.collectionOut(
ingo@535:                 request,
ingo@535:                 collection.identifier(),
ingo@535:                 type + "_chartinfo");
ingo@535: 
ingo@535:             Document info = XMLUtils.parseDocument(in);
ingo@535: 
ingo@535:             return parseInfoDocument(info);
ingo@535:         }
ingo@535:         catch (IOException ioe) {
ingo@535:             // do nothing
ingo@535:         }
ingo@535: 
ingo@535:         System.err.println("Error while fetching chart info.");
ingo@535: 
ingo@535:         throw new ServerException(EXCEPTION_STRING);
ingo@535:     }
ingo@535: 
ingo@535: 
ingo@535:     /**
ingo@535:      * This method returns a document which might contain parameters to adjust
ingo@535:      * chart settings. The document is created using the information that are
ingo@535:      * contained in the request object.
ingo@535:      *
ingo@535:      * @param req The request document.
ingo@535:      *
ingo@535:      * @return a document to adjust chart settings.
ingo@535:      */
ingo@535:     protected Document getChartAttributes(int width, int height) {
ingo@535:         Document doc = XMLUtils.newDocument();
ingo@535: 
ingo@535:         ElementCreator ec = new ElementCreator(
ingo@535:             doc,
ingo@535:             ArtifactNamespaceContext.NAMESPACE_URI,
ingo@535:             ArtifactNamespaceContext.NAMESPACE_PREFIX);
ingo@535: 
ingo@535:         Element size = ec.create("size");
ingo@535: 
ingo@535:         ec.addAttr(size, "width", String.valueOf(width), true);
ingo@535:         ec.addAttr(size, "height", String.valueOf(height), true);
ingo@535: 
ingo@535:         doc.appendChild(size);
ingo@535: 
ingo@535:         return doc;
ingo@535:     }
ingo@535: 
ingo@535: 
ingo@535:     /**
ingo@535:      * Parses the chart info document and extract the Transform2D values.
ingo@535:      *
ingo@535:      * @param doc The chart info document.
ingo@535:      *
ingo@535:      * @return a Transform2D object to transfrom pixel coordinates into chart
ingo@535:      * coordinates.
ingo@535:      */
ingo@535:     protected Transform2D parseInfoDocument(Document doc) {
ingo@535:         System.out.println("ChartInfoServiceImpl.parseInfoDocument");
ingo@535: 
ingo@535:         Node matrix = (Node) XMLUtils.xpath(
ingo@535:             doc,
ingo@535:             XPATH_TRANSFORM_MATRIX,
ingo@535:             XPathConstants.NODE,
ingo@535:             ArtifactNamespaceContext.INSTANCE);
ingo@535: 
ingo@535:         if (matrix == null) {
ingo@535:             return new Transform2D(1d, 1d, 0d, 0d);
ingo@535:         }
ingo@535: 
ingo@535:         String sx = XMLUtils.xpathString(
ingo@535:             matrix, "@art:sx", ArtifactNamespaceContext.INSTANCE);
ingo@535: 
ingo@535:         String sy = XMLUtils.xpathString(
ingo@535:             matrix, "@art:sy", ArtifactNamespaceContext.INSTANCE);
ingo@535: 
ingo@535:         String tx = XMLUtils.xpathString(
ingo@535:             matrix, "@art:tx", ArtifactNamespaceContext.INSTANCE);
ingo@535: 
ingo@535:         String ty = XMLUtils.xpathString(
ingo@535:             matrix, "@art:ty", ArtifactNamespaceContext.INSTANCE);
ingo@535: 
ingo@535:         if (sx != null && sy != null && tx != null && ty != null) {
ingo@535:             try {
ingo@535:                 return new Transform2D(
ingo@535:                     Double.parseDouble(sx),
ingo@535:                     Double.parseDouble(sy),
ingo@535:                     Double.parseDouble(tx),
ingo@535:                     Double.parseDouble(ty));
ingo@535:             }
ingo@535:             catch (NumberFormatException nfe) {
ingo@535:                 System.err.println("Error while parsing matrix values.");
ingo@535:             }
ingo@535:         }
ingo@535: 
ingo@535:         System.err.println("No matrix values found.");
ingo@535: 
ingo@535:         return new Transform2D(1d, 1d, 0d, 0d);
ingo@535:     }
ingo@535: }
ingo@535: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :