--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-client/src/main/java/org/dive4elements/river/client/client/ui/AbstractUIProvider.java	Thu Apr 25 12:31:32 2013 +0200
@@ -0,0 +1,341 @@
+package de.intevation.flys.client.client.ui;
+
+import com.google.gwt.core.client.GWT;
+
+import com.smartgwt.client.util.SC;
+import com.smartgwt.client.widgets.Button;
+import com.smartgwt.client.widgets.Canvas;
+import com.smartgwt.client.widgets.Img;
+import com.smartgwt.client.widgets.events.ClickEvent;
+import com.smartgwt.client.widgets.events.ClickHandler;
+import com.smartgwt.client.widgets.layout.VLayout;
+
+import de.intevation.flys.client.client.FLYSConstants;
+import de.intevation.flys.client.client.event.HasStepBackHandlers;
+import de.intevation.flys.client.client.event.HasStepForwardHandlers;
+import de.intevation.flys.client.client.event.StepBackEvent;
+import de.intevation.flys.client.client.event.StepBackHandler;
+import de.intevation.flys.client.client.event.StepForwardEvent;
+import de.intevation.flys.client.client.event.StepForwardHandler;
+import de.intevation.flys.client.shared.model.Artifact;
+import de.intevation.flys.client.shared.model.ArtifactDescription;
+import de.intevation.flys.client.shared.model.Collection;
+import de.intevation.flys.client.shared.model.Data;
+import de.intevation.flys.client.shared.model.DataItem;
+import de.intevation.flys.client.shared.model.DataList;
+import de.intevation.flys.client.shared.model.DefaultData;
+import de.intevation.flys.client.shared.model.DefaultDataItem;
+
+import java.util.ArrayList;
+import java.util.List;
+
+
+/**
+ * An abstract UIProvider that provides some basic methods.
+ *
+ * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
+ */
+public abstract class AbstractUIProvider
+implements   UIProvider, HasStepForwardHandlers, ClickHandler,
+             HasStepBackHandlers
+{
+    private static final long serialVersionUID = -1610874613377494184L;
+
+    /** The message class that provides i18n strings. */
+    protected FLYSConstants MSG = GWT.create(FLYSConstants.class);
+
+    /** The StepForwardHandlers. */
+    protected List<StepForwardHandler> forwardHandlers;
+
+    /** The StepForwardHandlers. */
+    protected List<StepBackHandler> backHandlers;
+
+    /** The container that is used to position helper widgets. */
+    protected VLayout helperContainer;
+
+    /** The artifact that contains status information. */
+    protected Artifact artifact;
+
+    /** The Collection. */
+    protected Collection collection;
+
+    /** The ParameterList. */
+    protected ParameterList parameterList;
+
+    /**
+     * Creates a new UIProvider instance of this class.
+     */
+    public AbstractUIProvider() {
+        forwardHandlers = new ArrayList<StepForwardHandler>();
+        backHandlers    = new ArrayList<StepBackHandler>();
+    }
+
+
+    /**
+     * Appends a StepBackHandler that wants to listen to StepBackEvents.
+     *
+     * @param handler A new StepBackHandler.
+     */
+    @Override
+    public void addStepBackHandler(StepBackHandler handler) {
+        if (handler != null) {
+            backHandlers.add(handler);
+        }
+    }
+
+
+    /**
+     * Appends a StepForwardHandler that wants to listen to StepForwardEvents.
+     *
+     * @param handler A new StepForwardHandler.
+     */
+    @Override
+    public void addStepForwardHandler(StepForwardHandler handler) {
+        if (handler != null) {
+            forwardHandlers.add(handler);
+        }
+    }
+
+
+    /**
+     * This method is called after the user has clicked one of the buttons to
+     * step back to a previous state.
+     *
+     * @param e The StepBackEvent.
+     */
+    protected void fireStepBackEvent(StepBackEvent e) {
+        GWT.log("AbstractUIProvider - fireStepBackEvent() handlers: " + backHandlers.size());
+        for (StepBackHandler handler: backHandlers) {
+            handler.onStepBack(e);
+        }
+    }
+
+
+    /**
+     * This method is called after the user has clicked on the 'next' button to
+     * step to the next state.
+     *
+     * @param e The StepForwardEvent.
+     */
+    protected void fireStepForwardEvent(StepForwardEvent e) {
+        GWT.log("AbstractUIProvider - fireStepForwardEvent() handlers: " + forwardHandlers.size());
+        for (StepForwardHandler handler: forwardHandlers) {
+            handler.onStepForward(e);
+        }
+    }
+
+
+    /**
+     * This method is used to listen to click events on the 'next' button. The
+     * fireStepForwardEvent() method is called here.
+     *
+     * @param e The click event.
+     */
+    @Override
+    public void onClick(ClickEvent e) {
+        List<String> errors = validate();
+        if (errors == null || errors.isEmpty()) {
+            Data[] data = getData();
+            fireStepForwardEvent(new StepForwardEvent(data));
+        }
+        else {
+            showErrors(errors);
+        }
+    }
+
+
+    protected void showErrors(List<String> errors) {
+        StringBuilder sb = new StringBuilder();
+
+        for (String error: errors) {
+            sb.append(error);
+            sb.append("<br>");
+        }
+
+        SC.warn(sb.toString());
+    }
+
+
+    /**
+     * Creates the 'next' button to step forward to the next state.
+     *
+     * @return the 'next' button.
+     */
+    protected Canvas getNextButton() {
+        Button next = new Button(MSG.buttonNext());
+        next.addClickHandler(this);
+
+        return next;
+    }
+
+
+    @Override
+    public Canvas createHelpLink(DataList dataList, Data data) {
+        String iUrl    = GWT.getHostPageBaseURL() + MSG.getFeatureInfo();
+        String helpUrl = dataList.getHelpText();
+
+        return new ImgLink(iUrl, helpUrl, 30, 30, true);
+    }
+
+
+    /**
+     * Creates the 'back' button to step back to a previous state.
+     *
+     * @param targetState The identifier of the target state.
+     *
+     * @return the 'back' button.
+     */
+    protected Canvas getBackButton(final String targetState) {
+        String url = GWT.getHostPageBaseURL() + MSG.imageBack();
+        Img back   = new Img(url, 16, 16);
+
+        back.addClickHandler(new ClickHandler() {
+            @Override
+            public void onClick(ClickEvent event) {
+                fireStepBackEvent(new StepBackEvent(targetState));
+            }
+        });
+
+        return back;
+    }
+
+
+    /**
+     * This method injects a container that is used to position helper widgets.
+     *
+     * @param helperContainer A container that is used to position helper
+     * widgets.
+     */
+    @Override
+    public void setContainer(VLayout helperContainer) {
+        this.helperContainer = helperContainer;
+    }
+
+
+    /**
+     * This method injects an artifact that contains the status information.
+     *
+     * @param art An artifact containing status information.
+     */
+    @Override
+    public void setArtifact(Artifact art) {
+        this.artifact = art;
+    }
+
+
+    @Override
+    public void setCollection(Collection collection) {
+        this.collection = collection;
+    }
+
+
+    @Override
+    public void setParameterList(ParameterList list) {
+        this.parameterList = list;
+    }
+
+
+    public Collection getCollection() {
+        return collection;
+    }
+
+
+    /**
+     * This method greps the Data with name <i>name</i> from the list and
+     * returns it.
+     *
+     * @param items A list of Data.
+     * @param name The name of the Data that we are searching for.
+     *
+     * @return the Data with the name <i>name</i>.
+     */
+    protected Data getData(List<Data> data, String name) {
+        for (Data d: data) {
+            if (name.equals(d.getLabel())) {
+                return d;
+            }
+        }
+
+        return null;
+    }
+
+
+    protected String getDataValue(String state, String name) {
+        ArtifactDescription desc = artifact.getArtifactDescription();
+
+        DataList[] old = desc.getOldData();
+
+        for (DataList list: old) {
+            if (list == null) {
+                continue;
+            }
+            Data d = getData(list.getAll(), name);
+
+            if (d != null) {
+                return d.getItems()[0].getStringValue();
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * This method greps the DataItem with name <i>name</i> from the list and
+     * returns it.
+     *
+     * @param items A list of DataItems.
+     * @param name The name of the DataItem that we are searching for.
+     *
+     * @return the DataItem with the name <i>name</i>.
+     */
+    protected DataItem getDataItem(DataItem[] items, String name) {
+        for (DataItem item: items) {
+            if (name.equals(item.getLabel())) {
+                return item;
+            }
+        }
+
+        return null;
+    }
+
+
+    public List<String> validate() {
+        return new ArrayList<String>(); // FIXME: What's this?
+    }
+
+
+    /** Create simple DefaultData with single DataItem inside. */
+    public static DefaultData createDataArray(String name, String value) {
+        DataItem item = new DefaultDataItem(
+            name,
+            name,
+            value);
+
+        return new DefaultData(name,
+            null,
+            null,
+            new DataItem[] {item});
+    }
+
+
+    /**
+     * This method needs to be implemented by concrete subclasses. It should
+     * create a new Canvas object with a representation of <i>data</i>.
+     *
+     * @param data The data that should be displayed.
+     *
+     * @return a Canvas object that displays <i>data</i>.
+     */
+    @Override
+    public abstract Canvas create(DataList data);
+
+
+    /**
+     * This method needs to be implemented by concrete subclasses. It should
+     * return the selected data.
+     *
+     * @return the selected data.
+     */
+    protected abstract Data[] getData();
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :