--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/states/WDifferencesState.java	Fri Sep 09 10:07:14 2011 +0000
@@ -0,0 +1,97 @@
+package de.intevation.flys.artifacts.states;
+
+import java.util.List;
+
+import org.apache.log4j.Logger;
+
+import de.intevation.artifacts.CallContext;
+
+import de.intevation.artifactdatabase.state.Facet;
+
+import de.intevation.flys.artifacts.FLYSArtifact;
+import de.intevation.flys.artifacts.WINFOArtifact;
+
+import de.intevation.flys.artifacts.math.WKmsOperation;
+
+import de.intevation.flys.artifacts.model.DurationCurveFacet;
+import de.intevation.flys.artifacts.model.FacetTypes;
+import de.intevation.flys.artifacts.model.WKms;
+import de.intevation.flys.artifacts.model.WQKms;
+import de.intevation.flys.artifacts.model.WQDay;
+
+import de.intevation.flys.artifacts.model.DataFacet;
+import de.intevation.flys.artifacts.model.ReportFacet;
+import de.intevation.flys.artifacts.model.CalculationResult;
+
+import de.intevation.flys.artifacts.resources.Resources;
+
+import de.intevation.flys.utils.FLYSUtils;
+
+public class WDifferencesState
+extends      DefaultState
+implements   FacetTypes
+{
+    /** The logger that is used in this state. */
+    private static Logger logger = Logger.getLogger(WDifferencesState.class);
+
+    public WDifferencesState() {
+    }
+
+
+    /** Specify to display a datacage_twin_panel. */
+    @Override
+    protected String getUIProvider() {
+        return "datacage_twin_panel";
+    }
+
+
+    @Override
+    public Object computeAdvance(
+        FLYSArtifact artifact,
+        String       hash,
+        CallContext  context,
+        List<Facet>  facets,
+        Object       old
+    ) {
+        WINFOArtifact winfo = (WINFOArtifact)artifact;
+
+        // Get a data item (uuids) or parameterization of the respective
+        // artifacts.
+        // TODO Fix, choose artifacts/parameterization dynamically.
+        WINFOArtifact flys1 = (WINFOArtifact) FLYSUtils.getArtifact(
+            //"a110a16d-d155-4115-ab0d-c4c61101c9cb", //Collection
+            "a0ec533f-b05b-4dcd-9db3-7850686f90a2",
+            context);
+        WINFOArtifact flys2 = (WINFOArtifact) FLYSUtils.getArtifact(
+            //"8ebb696d-771a-4540-bd18-15e19744a6e2", //Collection
+            "ce5a2c4e-3f9c-4c4d-a35c-109dd8670992",
+            context);
+
+        if (flys1 == null) {
+            logger.warn("One of the artifacts (1) for diff calculation could not be loaded");
+        }
+        if (flys2 == null) {
+            logger.warn("One of the artifacts (2) for diff calculation could not be loaded");
+        }
+        WKms wkms = null;
+
+        if (flys1 != null && flys2 != null) {
+            WQKms[] minuend = (WQKms[]) flys1.getWaterlevelData().getData();
+            WQKms[] subtrahend = (WQKms[]) flys2.getWaterlevelData().getData();
+            wkms = WKmsOperation.SUBTRACTION.operate(minuend[0], subtrahend[0]);
+            logger.warn("Did a WKMSSubtraction");
+        }
+
+        if (facets != null) {
+            // TODO: pass computetype and state id.
+            //, ComputeType.ADVANCE, getID(), hash));
+            facets.add(new DataFacet(W_DIFFERENCES, "wdiff data"));
+        }
+        else {
+            logger.debug("Not adding facets in WDifferencesState.");
+        }
+
+        return wkms;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf-8 :