package de.intevation.gnv.action;

import de.intevation.gnv.action.sessionmodel.SessionModel;
import de.intevation.gnv.action.sessionmodel.SessionModelFactory;

import de.intevation.gnv.artifactdatabase.client.ArtifactDatabaseClient;
import de.intevation.gnv.artifactdatabase.client.ArtifactDatabaseClientFactory;

import de.intevation.gnv.artifactdatabase.objects.ArtifactDescription;

import de.intevation.gnv.util.ArtifactNamespaceContext;
import de.intevation.gnv.util.XMLUtils;
import de.intevation.gnv.util.XSLTransformer;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import javax.xml.xpath.XPathConstants;

import org.apache.log4j.Logger;

import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;

import org.w3c.dom.Node;

/**
 * @author Ingo Weinzierl (ingo.weinzierl@intevation.de)
 */
public class DescribeUIAction extends ArtifactDatabaseActionBase {

    public static final String XPATH_DYNAMIC_UI = "art:dynamic";
    public static final String XPATH_STATIC_UI  = "art:static";

    public static final String XSL_SHEET_DYNAMIC =
        "WEB-INF/config/templates/describe-ui.xsl";

    public static final String XSL_SHEET_STATIC =
        "WEB-INF/config/templates/describe-ui-static.xsl";

    private static Logger logger = Logger.getLogger(DescribeUIAction.class);


    public DescribeUIAction() {
        super();
    }


    @Override
    public ActionForward execute(
        ActionMapping       mapping,
        ActionForm          form,
        HttpServletRequest  request,
        HttpServletResponse response
    ) throws Exception
    {
        logger.info("describe user interface");
        try {
            // render describe document and create user interface
            SessionModel sm = SessionModelFactory.getInstance().getSessionModel(
                request);

            ArtifactDatabaseClient adc = ArtifactDatabaseClientFactory
                .getInstance().getArtifactDatabaseClient(getLocale(request));

            ArtifactDescription artifactDescription =
                adc.getCurrentStepDescription(
                    sm.getSelectedArtifactFactory(),
                    sm.getCurrentArtifact(),
                    true);

            Node currentUI = artifactDescription.getCurrentUI();
            if (currentUI != null) {
                XSLTransformer transformer = new XSLTransformer();

                String url = response.encodeURL(
                    mapping.findForward("back").getPath());
                transformer.addParameter("back-url", url);

                String fisUrl = response.encodeURL(
                    mapping.findForward("selectfis").getPath());
                transformer.addParameter("selectfis", fisUrl);

                // fetch dynamic part from describe document and transform it
                Node dynamicNode = (Node) XMLUtils.xpath(
                    currentUI,
                    XPATH_DYNAMIC_UI,
                    XPathConstants.NODE,
                    ArtifactNamespaceContext.INSTANCE
                );

                String ui = transformer.transform(
                    dynamicNode,
                    "UTF-8",
                    request.getRealPath(XSL_SHEET_DYNAMIC
                ));

                if (ui != null && ui.length() > 1)
                    request.setAttribute("ui", ui);

                // fetch static part from describe document and transform it
                Node staticNode = (Node) XMLUtils.xpath(
                    currentUI,
                    XPATH_STATIC_UI,
                    XPathConstants.NODE,
                    ArtifactNamespaceContext.INSTANCE
                );

                String staticUI = transformer.transform(
                    staticNode,
                    "UTF-8",
                    request.getRealPath(XSL_SHEET_STATIC));

                if (staticUI != null && staticUI.length() > 1)
                    request.setAttribute("staticui", staticUI); 
            }

            return super.execute(mapping, form, request, response);
        }
        catch (Exception e) {
            logger.error(e, e);
            request.setAttribute(
                CommunicationKeys.REQUEST_EXCEPTION_MESSAGE_ID,
                e.getMessage());

            return super.getExceptionForward(mapping);
        }
    }
}
// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf-8 :