source: main/trunk/greenstone3/src/java/org/greenstone/gsdl3/action/AppletAction.java@ 24993

package org.greenstone.gsdl3.action;

import org.greenstone.gsdl3.core.ModuleInterface;
import org.greenstone.gsdl3.util.*;
// XML classes
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

import java.util.HashMap;
import java.io.File;

import org.apache.log4j.*;

/** action class for handling applets */
public class AppletAction extends Action
{

    static Logger logger = Logger.getLogger(org.greenstone.gsdl3.action.AppletAction.class.getName());

    public Node process(Node message_node)
    {

        Element message = this.converter.nodeToElement(message_node);

        Element request = (Element) GSXML.getChildByTagName(message, GSXML.REQUEST_ELEM);
        Element result = this.doc.createElement(GSXML.MESSAGE_ELEM);
        Element page_response = this.doc.createElement(GSXML.RESPONSE_ELEM);
        result.appendChild(page_response);

        // get the collection and service params
        Element cgi_param_list = (Element) GSXML.getChildByTagName(request, GSXML.PARAM_ELEM + GSXML.LIST_MODIFIER);
        HashMap params = GSXML.extractParams(cgi_param_list, false);

        // request_type is display (d) or request (r)
        String request_type = (String) params.get(GSParams.REQUEST_TYPE);
        if (!request_type.equals("d") && !request_type.equals("r"))
        {
            logger.error("AppletAction Error: the rt arg should be either d or r, instead it was " + request_type + "!");
            return result;
        }

        String collection = (String) params.get(GSParams.COLLECTION);
        boolean coll_specified = true;
        String service_name = (String) params.get(GSParams.SERVICE);
        UserContext userContext = new UserContext(request);
        String to = null;
        if (collection == null || collection.equals(""))
        {
            coll_specified = false;
            to = service_name;
        }
        else
        {
            to = GSPath.appendLink(collection, service_name);
        }

        if (request_type.equals("r"))
        {
            // we are processing stuff for the applet send a message to the service, type="query", and take out the something element, and return that as our result - the applet must take xml

            Element mr_message = this.doc.createElement(GSXML.MESSAGE_ELEM);
            Element mr_request = GSXML.createBasicRequest(this.doc, GSXML.REQUEST_TYPE_PROCESS, to, userContext);
            mr_message.appendChild(mr_request);
            // just append all the params for now - should filter out unneeded ones
            mr_request.appendChild(this.doc.importNode(cgi_param_list, true));

            // process the request
            Element mr_response = (Element) this.mr.process(mr_message);
            // get the applet data out and pass it back as is. 
            String path = GSPath.appendLink(GSXML.RESPONSE_ELEM, GSXML.APPLET_DATA_ELEM);
            Element applet_info = GSXML.getFirstElementChild(GSXML.getNodeByPath(mr_response, path));
            //Element applet_info = (Element)GSXML.getNodeByPath(mr_response, path).getFirstChild();
            return applet_info;

        }

        // get the applet description, and the collection info if a collection is specified

        Element mr_message = this.doc.createElement(GSXML.MESSAGE_ELEM);
        Element applet_request = GSXML.createBasicRequest(this.doc, GSXML.REQUEST_TYPE_DESCRIBE, to, userContext);
        mr_message.appendChild(applet_request);

        Element mr_response = (Element) this.mr.process(mr_message);

        // add in the applet info
        String path = GSPath.appendLink(GSXML.RESPONSE_ELEM, GSXML.SERVICE_ELEM);
        //path = GSPath.appendLink(path, GSXML.APPLET_ELEM);
        Element service_elem = (Element) this.doc.importNode(GSXML.getNodeByPath(mr_response, path), true);
        Element applet_elem = (Element) GSXML.getChildByTagName(service_elem, GSXML.APPLET_ELEM);
        // must handle any params that have values that are not 
        // necessarily known by the service
        // should this be done here or by web receptionist??
        // cant really have an applet without web?
        editLocalParams(applet_elem, (String) config_params.get(GSConstants.LIBRARY_NAME), collection);
        page_response.appendChild(service_elem);

        return result;

    }

    /**
     * this method looks through the PARAMs of the applet description for
     * 'library' or 'collection'. If found, the params are set to the
     * appropriate values should this be done here or in the receptionist?
     */
    protected void editLocalParams(Element description, String library_name, String full_collection_name)
    {

        Node child = description.getFirstChild();
        while (child != null)
        {
            if (child.getNodeType() == Node.ELEMENT_NODE)
            {
                String param = child.getNodeName();
                if (param.equals("PARAM") || param.equals("param"))
                {
                    String name = ((Element) child).getAttribute("NAME");
                    if (name == null || name.equals(""))
                    {
                        // somethings wrong!!
                    }
                    else if (name.equals("library"))
                    {
                        ((Element) child).setAttribute("VALUE", library_name);
                    }
                    else if (name.equals("collection"))
                    {
                        ((Element) child).setAttribute("VALUE", full_collection_name);
                    }

                }
            }
            child = child.getNextSibling();
        }
    }

}