/**
 * The contents of this file are subject to the license and copyright
 * detailed in the LICENSE and NOTICE files at the root of the source
 * tree and available online at
 *
 * http://www.dspace.org/license/
 */
package org.dspace.app.webui.servlet;

import java.io.IOException;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.locks.*;

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

import org.apache.log4j.Logger;
import org.dspace.app.webui.util.JSPManager;
import org.dspace.authorize.AuthorizeException;
import org.dspace.authorize.AuthorizeManager;
import org.dspace.content.Collection;
import org.dspace.content.Community;
import org.dspace.core.Context;
import org.dspace.core.LogManager;

/**
 * Servlet for listing communities (and collections within them)
 * 
 * @author Robert Tansley
 * @version $Revision$
 */
public class CommunityListServlet extends DSpaceServlet
{
    
    // This will map community IDs to arrays of collections
    private Map<Integer, Collection[]> colMap;

    // This will map communityIDs to arrays of sub-communities
    private Map<Integer, Community[]> commMap;
    private static final Object staticLock = new Object();
    
    /** log4j category */
    private static Logger log = Logger.getLogger(CommunityListServlet.class);

    protected void doDSGet(Context context, HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException,
            SQLException, AuthorizeException
    { 
           synchronized (staticLock) 
           {
            colMap = new HashMap<Integer, Collection[]>();
            commMap = new HashMap<Integer, Community[]>();

            log.info(LogManager.getHeader(context, "view_community_list", ""));

            Community[] communities = Community.findAllTop(context);

            for (int com = 0; com < communities.length; com++) 
            {
                build(communities[com]);
            }

            // can they admin communities?
            if (AuthorizeManager.isAdmin(context)) 
            {
                // set a variable to create an edit button
                request.setAttribute("admin_button", Boolean.TRUE);
            }

            request.setAttribute("communities", communities);
            request.setAttribute("collections.map", colMap);
            request.setAttribute("subcommunities.map", commMap);
            JSPManager.showJSP(request, response, "/community-list.jsp");
           }
    }
    /*
     * Get all subcommunities and collections from a community
     */
    private void build(Community c) throws SQLException {

        Integer comID = Integer.valueOf(c.getID());

        // Find collections in community
        Collection[] colls = c.getCollections();
        colMap.put(comID, colls);

        // Find subcommunties in community
        Community[] comms = c.getSubcommunities();
        
        // Get all subcommunities for each communities if they have some
        if (comms.length > 0) 
        {
            commMap.put(comID, comms);
            
            for (int sub = 0; sub < comms.length; sub++) {
                
                build(comms[sub]);
            }
        }
    }
}