--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/artifacts/src/main/java/org/dive4elements/river/artifacts/states/DischargeState.java	Thu Apr 25 15:23:37 2013 +0200
@@ -0,0 +1,161 @@
+package org.dive4elements.river.artifacts.states;
+
+import java.util.List;
+
+import org.apache.log4j.Logger;
+
+import org.dive4elements.artifacts.Artifact;
+import org.dive4elements.artifacts.CallContext;
+
+import org.dive4elements.artifacts.common.model.KVP;
+
+import org.dive4elements.river.model.DischargeZone;
+import org.dive4elements.river.model.River;
+
+import org.dive4elements.river.artifacts.FLYSArtifact;
+import org.dive4elements.river.utils.FLYSUtils;
+
+
+public class DischargeState extends MultiIntArrayState {
+
+    public static final String MAIN_CHANNEL  = "main_channel";
+    public static final String TOTAL_CHANNEL = "total_channel";
+
+
+    private static final Logger logger = Logger.getLogger(DischargeState.class);
+
+
+    /** Let client display a matrix. */
+    @Override
+    public String getUIProvider() {
+        return "parameter-matrix";
+    }
+
+
+    /**
+     * This method fetches all DischargeZones for a given river (extracted from
+     * <i>artifact</i>) and returns a KVP[] where the key is the ID of the
+     * DischargeZone and the value is a string that consists of lower discharge
+     * and upper discharge.
+     *
+     * @param artifact Needs to be a FLYSArtifact that provides river
+     * information.
+     * @param parameterName The name of a parameter.
+     *
+     * @return a KVP[].
+     */
+    @Override
+    protected KVP<Integer, String>[] getOptions(
+        Artifact artifact,
+        String   parameterName
+    )
+    throws IllegalArgumentException
+    {
+        if (!testParameterName(parameterName)) {
+            throw new IllegalArgumentException(
+                "Invalid parameter for state: '" + parameterName + "'");
+        }
+
+        List<DischargeZone> zones = getDischargeZones(artifact);
+
+        KVP[] kvp = new KVP[zones.size()];
+
+        for (int i = 0, Z = zones.size(); i < Z; i++) {
+            DischargeZone zone = zones.get(i);
+
+            String lower = zone.getLowerDischarge();
+            String upper = zone.getUpperDischarge();
+
+            if (lower.equals(upper)) {
+                kvp[i] = new KVP(zone.getId(), lower);
+            }
+            else {
+                kvp[i] = new KVP(zone.getId(), lower + " - " + upper);
+            }
+        }
+
+        return kvp;
+    }
+
+
+    @Override
+    protected String getLabelFor(
+        CallContext cc,
+        String      parameterName,
+        int         value
+    ) throws IllegalArgumentException
+    {
+        if (!testParameterName(parameterName)) {
+            throw new IllegalArgumentException(
+                "Invalid parameter for state: '" + parameterName + "'");
+        }
+
+        DischargeZone zone = DischargeZone.getDischargeZoneById(value);
+
+        if (zone == null) {
+            throw new IllegalArgumentException(
+                "Invalid id for DischargeZone: '" + value + "'");
+        }
+
+        String lo = zone.getLowerDischarge();
+        String hi = zone.getUpperDischarge();
+
+        return hi != null && !lo.equals(hi)
+            ? lo + " - " + hi
+            : lo;
+    }
+
+
+    /**
+     * This method might be used to test, if a parameter name is handled by this
+     * state.
+     *
+     * @param parameterName The name of a parameter.
+     *
+     * @return true, if parameterName is one of <i>MAIN_CHANNEL</i> or
+     * <i>TOTAL_CHANNEL</i>. Otherwise false.
+     */
+    protected boolean testParameterName(String parameterName) {
+        if (parameterName == null || parameterName.length() == 0) {
+            return false;
+        }
+        else if (parameterName.equals(MAIN_CHANNEL)) {
+            return true;
+        }
+        else if (parameterName.equals(TOTAL_CHANNEL)) {
+            return true;
+        }
+        else {
+            return false;
+        }
+    }
+
+
+    /**
+     * Returns all discharge zones for a given river. The river information is
+     * extracted from <i>artifact</i> using FLYSUtils.getRiver().
+     *
+     * @param artifact Needs to be a FLYSArtifact that stores a rivername.
+     *
+     * @return a list of DischargeZones.
+     *
+     * @throws IllegalArgumentException if no river information is provided by
+     * <i>artifact</i>.
+     */
+    protected List<DischargeZone> getDischargeZones(Artifact artifact)
+    throws IllegalArgumentException
+    {
+        River river = FLYSUtils.getRiver((FLYSArtifact) artifact);
+
+        if (river == null) {
+            throw new IllegalArgumentException("No river found");
+        }
+
+        List<DischargeZone> zones = DischargeZone.getDischargeZones(river);
+
+        logger.debug("Found " + zones.size() + " DischargeZones.");
+
+        return zones;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :