--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-client/src/main/java/de/intevation/flys/client/server/ChartInfoServiceImpl.java	Wed Jun 01 08:15:58 2011 +0000
@@ -0,0 +1,164 @@
+package de.intevation.flys.client.server;
+
+import java.io.InputStream;
+import java.io.IOException;
+
+import javax.xml.xpath.XPathConstants;
+
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+import org.w3c.dom.Node;
+
+import com.google.gwt.user.server.rpc.RemoteServiceServlet;
+
+import de.intevation.artifacts.common.ArtifactNamespaceContext;
+import de.intevation.artifacts.common.utils.ClientProtocolUtils;
+import de.intevation.artifacts.common.utils.XMLUtils;
+import de.intevation.artifacts.common.utils.XMLUtils.ElementCreator;
+
+import de.intevation.artifacts.httpclient.http.HttpClient;
+import de.intevation.artifacts.httpclient.http.HttpClientImpl;
+
+import de.intevation.flys.client.shared.Transform2D;
+import de.intevation.flys.client.shared.exceptions.ServerException;
+import de.intevation.flys.client.shared.model.Collection;
+
+import de.intevation.flys.client.client.services.ChartInfoService;
+
+
+/**
+ * This service fetches a document that contains meta information for a specific
+ * chart.
+ *
+ * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
+ */
+public class ChartInfoServiceImpl
+extends      RemoteServiceServlet
+implements   ChartInfoService
+{
+    public static final String XPATH_TRANSFORM_MATRIX =
+        "/art:chartinfo/art:transformation-matrix";
+
+    public static final String EXCEPTION_STRING = "error_chart_info_service";
+
+
+    public Transform2D getChartInfo(
+        Collection collection,
+        String     url,
+        String     locale,
+        String     type,
+        int        width,
+        int        height)
+    throws ServerException
+    {
+        System.out.println("ChartInfoServiceImpl.getChartInfo");
+
+        Document request = ClientProtocolUtils.newOutCollectionDocument(
+                collection.identifier(),
+                type,
+                type,
+                getChartAttributes(width, height));
+
+        try {
+            HttpClient client = new HttpClientImpl(url, locale);
+            InputStream in    = client.collectionOut(
+                request,
+                collection.identifier(),
+                type + "_chartinfo");
+
+            Document info = XMLUtils.parseDocument(in);
+
+            return parseInfoDocument(info);
+        }
+        catch (IOException ioe) {
+            // do nothing
+        }
+
+        System.err.println("Error while fetching chart info.");
+
+        throw new ServerException(EXCEPTION_STRING);
+    }
+
+
+    /**
+     * This method returns a document which might contain parameters to adjust
+     * chart settings. The document is created using the information that are
+     * contained in the request object.
+     *
+     * @param req The request document.
+     *
+     * @return a document to adjust chart settings.
+     */
+    protected Document getChartAttributes(int width, int height) {
+        Document doc = XMLUtils.newDocument();
+
+        ElementCreator ec = new ElementCreator(
+            doc,
+            ArtifactNamespaceContext.NAMESPACE_URI,
+            ArtifactNamespaceContext.NAMESPACE_PREFIX);
+
+        Element size = ec.create("size");
+
+        ec.addAttr(size, "width", String.valueOf(width), true);
+        ec.addAttr(size, "height", String.valueOf(height), true);
+
+        doc.appendChild(size);
+
+        return doc;
+    }
+
+
+    /**
+     * Parses the chart info document and extract the Transform2D values.
+     *
+     * @param doc The chart info document.
+     *
+     * @return a Transform2D object to transfrom pixel coordinates into chart
+     * coordinates.
+     */
+    protected Transform2D parseInfoDocument(Document doc) {
+        System.out.println("ChartInfoServiceImpl.parseInfoDocument");
+
+        XMLDebug.out(doc);
+
+        Node matrix = (Node) XMLUtils.xpath(
+            doc,
+            XPATH_TRANSFORM_MATRIX,
+            XPathConstants.NODE,
+            ArtifactNamespaceContext.INSTANCE);
+
+        if (matrix == null) {
+            return new Transform2D(1d, 1d, 0d, 0d);
+        }
+
+        String sx = XMLUtils.xpathString(
+            matrix, "@art:sx", ArtifactNamespaceContext.INSTANCE);
+
+        String sy = XMLUtils.xpathString(
+            matrix, "@art:sy", ArtifactNamespaceContext.INSTANCE);
+
+        String tx = XMLUtils.xpathString(
+            matrix, "@art:tx", ArtifactNamespaceContext.INSTANCE);
+
+        String ty = XMLUtils.xpathString(
+            matrix, "@art:ty", ArtifactNamespaceContext.INSTANCE);
+
+        if (sx != null && sy != null && tx != null && ty != null) {
+            try {
+                return new Transform2D(
+                    Double.parseDouble(sx),
+                    Double.parseDouble(sy),
+                    Double.parseDouble(tx),
+                    Double.parseDouble(ty));
+            }
+            catch (NumberFormatException nfe) {
+                System.err.println("Error while parsing matrix values.");
+            }
+        }
+
+        System.err.println("No matrix values found.");
+
+        return new Transform2D(1d, 1d, 0d, 0d);
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :