source: trunk/gsdl3/src/java/org/greenstone/gsdl3/service/GS3MGRetrieve.java@ 8439

/*
 *    GS3MGRetrieve.java
 *    Copyright (C) 2002 New Zealand Digital Library, http://www.nzdl.org
 *
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
package org.greenstone.gsdl3.service;


// Greenstone classes
import org.greenstone.mg.*;
import org.greenstone.gsdl3.util.*;

// XML classes
import org.w3c.dom.Element;

// General Java classes
import java.io.File;


/** The content retrieval class for GS3 building
 *
 * @author <a href="mailto:[email protected]">Katherine Don</a>
 * @version $Revision: 8439 $
 */

public class GS3MGRetrieve
    extends ServiceRack {
    // the services on offer
    protected static final String DOCUMENT_CONTENT_RETRIEVE_SERVICE = "DocumentContentRetrieve";
    
    // Parameters used
    private static final String INDEX_PARAM = "index";

    // Elements used in the config file that are specific to this class
    private static final String DEFAULT_INDEX_ELEM = "defaultIndex";

    private MGWrapper mg_src = null;
    protected SQLQuery database = null;
    
    protected Element config_info = null; // the xml from the config file

    private String default_index = null;

    /** constructor */
    public GS3MGRetrieve()
    {
    this.database = new SQLQuery();
    this.mg_src = new MGWrapper();
    }


    /** configure this service */
    public boolean configure(Element info, Element extra_info)
    {
    this.config_info = info;
    // Do specific configuration
    System.out.println("Configuring GS3MGRetrieve...");
    // System.out.println("info:\n" + converter_.getString(info));
    // System.out.println("extra_info:\n" + converter_.getString(extra_info));

    // Get the default index out of <defaultIndex> (buildConfig.xml)
    Element def = (Element) GSXML.getChildByTagName(info, DEFAULT_INDEX_ELEM);
    if (def != null) {
        this.default_index = def.getAttribute(GSXML.NAME_ATT);
    }
    if (this.default_index == null || this.default_index.equals("")) {
        System.err.println("Error: default index not specified!");
        return false;
    }

    // System.out.println("Default index: " + this.default_index);
    Element dcr_service = this.doc.createElement(GSXML.SERVICE_ELEM);
    dcr_service.setAttribute(GSXML.TYPE_ATT, GSXML.SERVICE_TYPE_RETRIEVE);
    dcr_service.setAttribute(GSXML.NAME_ATT, DOCUMENT_CONTENT_RETRIEVE_SERVICE);
    this.short_service_info.appendChild(dcr_service);

    // check that site_home is set
    if (this.site_home == null || this.site_home.equals("")) {
        System.err.println("GS3Retrieve Error: site_home is not set, so cannot work out the site name and cannot determine the database name");
        return false;
    }
    String site_name = this.site_home.substring(this.site_home.lastIndexOf(File.separator)+1);
    if (site_name.equals("")) {
        System.err.println("GS3Retrieve Error: Cannot extract the site name from site home: "+this.site_home);
        return false;
    }
    if (!database.setDatabase(site_name+"_"+this.cluster_name)) {
        System.err.println("GS3Retrieve Error: Could not open SQL database!");
        return false;
    }

    // look for document display format
    String path = GSPath.appendLink(GSXML.DISPLAY_ELEM, GSXML.FORMAT_ELEM);
    Element display_format = (Element)GSXML.getNodeByPath(extra_info, path);
    if (display_format != null) {
        this.format_info_map.put(DOCUMENT_CONTENT_RETRIEVE_SERVICE, this.doc.importNode(display_format, true));
        // should we make a copy?
    }

    return true;
    }

    protected Element getServiceDescription(String service_id, String lang, String subset) {
    if (service_id.equals(DOCUMENT_CONTENT_RETRIEVE_SERVICE)) {
        Element dcr_service = this.doc.createElement(GSXML.SERVICE_ELEM);
        dcr_service.setAttribute(GSXML.TYPE_ATT, GSXML.SERVICE_TYPE_RETRIEVE);
        dcr_service.setAttribute(GSXML.NAME_ATT, DOCUMENT_CONTENT_RETRIEVE_SERVICE);
        return dcr_service;
    }

    return null;
    }
    /** Retrieve the content of a document */
    protected Element processDocumentContentRetrieve(Element request)
    {
    // Create a new (empty) result message
    Element result = this.doc.createElement(GSXML.RESPONSE_ELEM);
    result.setAttribute(GSXML.FROM_ATT, DOCUMENT_CONTENT_RETRIEVE_SERVICE);
    result.setAttribute(GSXML.TYPE_ATT, GSXML.REQUEST_TYPE_PROCESS);

    // Get the parameters of the request - no parameters at this stage
    //Element param_list = (Element) GSXML.getChildByTagName(request, GSXML.PARAM_ELEM+GSXML.LIST_MODIFIER);

    // Get the request content 
    
    Element query_doc_list = (Element) GSXML.getChildByTagName(request, GSXML.DOC_NODE_ELEM+GSXML.LIST_MODIFIER);
    if (query_doc_list == null) {
        System.err.println("Error: DocumentContentRetrieve request specified no doc nodes.\n");
        return result;
    }
    
    Element doc_list = this.doc.createElement(GSXML.DOC_NODE_ELEM+GSXML.LIST_MODIFIER);
    result.appendChild(doc_list);
    
    // The location of the MG index and text files
    String basedir = GSFile.collectionBaseDir(this.site_home, this.cluster_name) + File.separatorChar;  // Needed by MG
    String textdir = GSFile.collectionTextPath("index");//this.cluster_name);
    // index is only needed to start up MG, not used so just use the default index
    String indexpath = GSFile.collectionIndexPath("index"/*this.cluster_name*/, this.default_index);
    this.mg_src.setIndex(indexpath);
    
    // Get the documents
    String[] doc_ids = GSXML.getAttributeValuesFromList(query_doc_list, 
                                 GSXML.NODE_ID_ATT);
    for (int i = 0; i < doc_ids.length; i++) {
        //ystem.out.println("getting doc id "+doc_ids[i]);
        String doc_id = doc_ids[i];
        if (GS3OID.needsTranslating(doc_id)) {
        //doc_id = this.gdbm_src.translateOID(doc_id);
        doc_id = GS3OID.translateOID(doc_id);
        //ystem.out.println("translated id = "+doc_id);
        }
        if (GS3OID.isDocTop(doc_id) && database.isHierarchicalDocument(doc_id)) {
        // if we have a whole doc id, and the document is hierarchical,
        // we want to change the id to be the top id of the section 
        // hierarchy
            doc_id = GS3OID.createOID(doc_id, "1");
        }
        String doc_num = this.database.OID2MGNum(doc_id);       
        // doc nums have the index prefixed 
        doc_num = doc_num.substring(doc_num.indexOf(".")+1);
        int doc_int = Integer.parseInt(doc_num);
        
        String doc_content = "";
        try {
        doc_content = this.mg_src.getDocument(basedir, textdir, doc_int);
        } catch (Exception e) {
        System.out.println("exception happended with mg_src.getDocument()");
        doc_content = "this is the content for section hash id "+ doc_id+", mg doc num "+doc_int+"\n";
        }
        //ystem.out.println("Doc content: " + doc_content + "|");
        //ystem.out.println("Doc ID: " + doc_id);
        // remove any ctrl-c or ctrl-b (I hope these are the right codes)
        doc_content = doc_content.replaceAll("\u0002|\u0003", "");
        // replace _httpimg_ with the correct address
        //doc_content = resolveImages(doc_content, doc_id);
        // Stick it in a text node
        Element doc = this.doc.createElement(GSXML.DOC_NODE_ELEM);
        doc.setAttribute(GSXML.NODE_ID_ATT, doc_id);
        GSXML.addDocText(this.doc, doc, doc_content);
        doc_list.appendChild(doc);
    }

    return result;
    }

}