--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gwt-client/src/main/java/org/dive4elements/river/client/server/ChartInfoServiceImpl.java	Thu Apr 25 15:23:37 2013 +0200
@@ -0,0 +1,283 @@
+package org.dive4elements.river.client.server;
+
+import java.io.InputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+import java.util.Map;
+
+import javax.xml.xpath.XPathConstants;
+
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+import org.w3c.dom.NodeList;
+
+import org.apache.log4j.Logger;
+
+import com.google.gwt.user.server.rpc.RemoteServiceServlet;
+
+import org.dive4elements.artifacts.common.ArtifactNamespaceContext;
+import org.dive4elements.artifacts.common.utils.ClientProtocolUtils;
+import org.dive4elements.artifacts.common.utils.XMLUtils;
+
+import org.dive4elements.artifacts.httpclient.http.HttpClient;
+import org.dive4elements.artifacts.httpclient.http.HttpClientImpl;
+
+import org.dive4elements.river.client.shared.Transform2D;
+import org.dive4elements.river.client.shared.exceptions.ServerException;
+import org.dive4elements.river.client.shared.model.Axis;
+import org.dive4elements.river.client.shared.model.DateAxis;
+import org.dive4elements.river.client.shared.model.NumberAxis;
+import org.dive4elements.river.client.shared.model.ChartInfo;
+import org.dive4elements.river.client.shared.model.Collection;
+
+import org.dive4elements.river.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
+{
+    private static final Logger logger =
+        Logger.getLogger(ChartInfoServiceImpl.class);
+
+    public static final String XPATH_TRANSFORM_MATRIX =
+        "/art:chartinfo/art:transformation-matrix/art:matrix";
+
+    public static final String XPATH_X_AXES =
+        "/art:chartinfo/art:axes/art:domain";
+
+    public static final String XPATH_Y_AXES =
+        "/art:chartinfo/art:axes/art:range";
+
+    public static final String EXCEPTION_STRING = "error_chart_info_service";
+
+
+    public ChartInfo getChartInfo(
+        Collection          collection,
+        String              locale,
+        String              type,
+        Map<String, String> attr)
+    throws ServerException
+    {
+        logger.info("ChartInfoServiceImpl.getChartInfo");
+
+        String url  = getServletContext().getInitParameter("server-url");
+
+        Document request = ClientProtocolUtils.newOutCollectionDocument(
+                collection.identifier(),
+                type,
+                type,
+                ChartServiceHelper.getChartAttributes(attr));
+
+        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) {
+            ioe.printStackTrace();
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+
+        logger.debug("Error while fetching chart info.");
+
+        throw new ServerException(EXCEPTION_STRING);
+    }
+
+
+    /**
+     * Parse ChartInfo-Part of document, create Transforms and axes
+     * from it.
+     */
+    protected ChartInfo parseInfoDocument(Document doc) {
+        Transform2D[] transformer = parseTransformationMatrix(doc);
+        Axis[]      xAxes         = parseXAxes(doc);
+        Axis[]      yAxes         = parseYAxes(doc);
+
+        return new ChartInfo(xAxes, yAxes, transformer);
+    }
+
+
+    protected Axis[] parseXAxes(Document doc) {
+        logger.debug("ChartInfoServiceImpl.parseXAxes");
+
+        NodeList axes = (NodeList) XMLUtils.xpath(
+            doc,
+            XPATH_X_AXES,
+            XPathConstants.NODESET,
+            ArtifactNamespaceContext.INSTANCE);
+
+        return parseAxes(axes);
+    }
+
+
+    protected Axis[] parseYAxes(Document doc) {
+        logger.debug("ChartInfoServiceImpl.parseYAxes");
+
+        NodeList axes = (NodeList) XMLUtils.xpath(
+            doc,
+            XPATH_Y_AXES,
+            XPathConstants.NODESET,
+            ArtifactNamespaceContext.INSTANCE);
+
+        return parseAxes(axes);
+    }
+
+
+    protected Axis[] parseAxes(NodeList axes) {
+        logger.debug("ChartInfoServiceImpl.parseAxes");
+
+        int count = axes != null ? axes.getLength() : 0;
+
+        logger.debug("Chart has " + count + " axes.");
+
+        if (count == 0) {
+            return null;
+        }
+
+        Axis[] result = new Axis[count];
+
+        String ns = ArtifactNamespaceContext.NAMESPACE_URI;
+
+        for (int i = 0; i < count; i++) {
+            Element node = (Element) axes.item(i);
+
+            String posStr   = node.getAttributeNS(ns, "pos");
+            String fromStr  = node.getAttributeNS(ns, "from");
+            String toStr    = node.getAttributeNS(ns, "to");
+            String minStr   = node.getAttributeNS(ns, "min");
+            String maxStr   = node.getAttributeNS(ns, "max");
+            String axisType = node.getAttributeNS(ns, "axistype");
+
+            try {
+                int    pos  = Integer.parseInt(posStr);
+
+                if (pos >= result.length) {
+                    // this should never happen
+                    logger.debug("The axis is out of valid range: " + pos);
+                    continue;
+                }
+
+                if (axisType != null && axisType.equals(DateAxis.TYPE)) {
+                    long from = Long.parseLong(fromStr);
+                    long to   = Long.parseLong(toStr);
+                    long min  = Long.parseLong(minStr);
+                    long max  = Long.parseLong(maxStr);
+
+                    if (logger.isDebugEnabled()) {
+                        logger.debug("date axis from: " + new Date(from));
+                        logger.debug("date axis to  : " + new Date(to));
+                        logger.debug("date axis min : " + new Date(min));
+                        logger.debug("date axis max : " + new Date(max));
+                    }
+
+                    result[pos] = new DateAxis(pos, from, to, min, max);
+                }
+                else {
+                    double from = Double.parseDouble(fromStr);
+                    double to   = Double.parseDouble(toStr);
+                    double min  = Double.parseDouble(minStr);
+                    double max  = Double.parseDouble(maxStr);
+
+                    result[pos] = new NumberAxis(pos, from, to, min, max);
+                }
+            }
+            catch (NumberFormatException nfe) {
+                nfe.printStackTrace();
+            }
+        }
+
+        logger.debug("Parsed " + result.length + " axes");
+
+        return result;
+    }
+
+
+    /**
+     * 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[] parseTransformationMatrix(Document doc) {
+        logger.debug("ChartInfoServiceImpl.parseTransformationMatrix");
+
+        NodeList matrix = (NodeList) XMLUtils.xpath(
+            doc,
+            XPATH_TRANSFORM_MATRIX,
+            XPathConstants.NODESET,
+            ArtifactNamespaceContext.INSTANCE);
+
+        int num = matrix != null ? matrix.getLength() : 0;
+
+        List<Transform2D> transformer = new ArrayList<Transform2D>(num);
+
+        for (int i = 0; i < num; i++) {
+            Transform2D t = createTransformer((Element) matrix.item(i));
+
+            if (t == null) {
+                logger.warn("Broken transformation matrix at pos: " + i);
+                continue;
+            }
+
+            transformer.add(t);
+        }
+
+        return transformer.toArray(new Transform2D[num]);
+    }
+
+
+    protected Transform2D createTransformer(Element matrix) {
+        String ns = ArtifactNamespaceContext.NAMESPACE_URI;
+
+        String sx    = matrix.getAttributeNS(ns, "sx");
+        String sy    = matrix.getAttributeNS(ns, "sy");
+        String tx    = matrix.getAttributeNS(ns, "tx");
+        String ty    = matrix.getAttributeNS(ns, "ty");
+        String xType = matrix.getAttributeNS(ns, "xtype");
+        String yType = matrix.getAttributeNS(ns, "ytype");
+
+        xType = xType == null || xType.length() == 0 ? "number" : xType;
+        yType = yType == null || yType.length() == 0 ? "number" : yType;
+
+        if (sx != null && sy != null && tx != null && ty != null) {
+            try {
+                logger.debug("Create new Transform2D with x format: " + xType);
+                logger.debug("Create new Transform2D with y format: " + yType);
+
+                return new Transform2D(
+                    Double.parseDouble(sx),
+                    Double.parseDouble(sy),
+                    Double.parseDouble(tx),
+                    Double.parseDouble(ty),
+                    xType, yType);
+            }
+            catch (NumberFormatException nfe) {
+                logger.warn("Error while parsing matrix values.");
+            }
+        }
+
+        logger.warn("No matrix values found.");
+
+        return new Transform2D(1d, 1d, 0d, 0d);
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :