/*
 *  Copyright 2010 Anyware Services
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package org.ametys.web;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import org.apache.cocoon.environment.Request;
import org.apache.commons.lang.StringUtils;

import org.ametys.core.observation.Event;
import org.ametys.core.user.population.PopulationContextHelper;
import org.ametys.plugins.repository.AmetysObject;
import org.ametys.web.repository.SiteAwareAmetysObject;
import org.ametys.web.repository.page.SitemapElement;
import org.ametys.web.repository.page.ZoneItem;
import org.ametys.web.repository.site.Site;

/**
 * Helper for web
 */
public final class WebHelper
{
    private WebHelper()
    {
        // Empty
    }
    
    /**
     * Get the site name from the request.
     * The site name is searched in the following order: the 'siteName' request parameter, the 'site' request attribute, the 'siteName' request attribute.
     * @param request the request. Cannot be null.
     * @return the site name or <code>null</code> if not found
     */
    public static String getSiteName(Request request)
    {
        return getSiteName(request, null);
    }
    
    /**
     * Get the site name from a object or current request.
     * The site name is searched in the following order: the Ametys object, the 'siteName' request parameter, the 'site' request attribute, the 'siteName' request attribute.
     * @param request the request. Cannot be null.
     * @param object the object. Can be null.
     * @return the site name or <code>null</code> if not found
     */
    public static String getSiteName(Request request, AmetysObject object)
    {
        String siteName = null;
        if (object != null && object instanceof SiteAwareAmetysObject)
        {
            siteName = ((SiteAwareAmetysObject) object).getSiteName();
        }
        else
        {
            siteName = request.getParameter("siteName");
            
            if (siteName == null)
            {
                siteName = (String) request.getAttribute("siteName"); // From FO request
            }
            
            if (siteName == null)
            {
                siteName = (String) request.getAttribute(WebConstants.REQUEST_ATTR_SITE_NAME);
            }
            
            if (siteName == null)
            {
                Site site = (Site) request.getAttribute(WebConstants.REQUEST_ATTR_SITE);
                if (site != null)
                {
                    siteName = site.getName();
                }
            }
        }
        
        return siteName;
    }
    
    /**
     * Retrieves the site from an observation {@link Event}.<br>
     * This method search in the events' arguments to find :<br>
     * <ul>
     * <li><code>ObservationConstants.ARGS_SITE</code>
     * <li><code>ObservationConstants.ARGS_PAGE</code>
     * <li><code>ObservationConstants.ARGS_ZONE_ITEM</code>
     * <li><code>ObservationConstants.ARGS_ACL_CONTEXT</code>
     * <li><code>object</code> if it's instance of {@link SiteAwareAmetysObject}
     * </ul>
     * @param event the {@link Event}.
     * @return the current site or null if not found.
     */
    public static Site findSite(Event event)
    {
        Map<String, Object> args = event.getArguments();
        
        if (args.containsKey(ObservationConstants.ARGS_SITE))
        {
            return (Site) args.get(ObservationConstants.ARGS_SITE);
        }
        else if (args.containsKey(ObservationConstants.ARGS_SITEMAP_ELEMENT))
        {
            return ((SitemapElement) args.get(ObservationConstants.ARGS_SITEMAP_ELEMENT)).getSite();
        }
        else if (args.containsKey(ObservationConstants.ARGS_ZONE_ITEM))
        {
            return ((ZoneItem) args.get(ObservationConstants.ARGS_ZONE_ITEM)).getZone().getSitemapElement().getSite();
        }
        else if (args.containsKey(org.ametys.core.ObservationConstants.ARGS_ACL_CONTEXT))
        {
            Object object = args.get(org.ametys.core.ObservationConstants.ARGS_ACL_CONTEXT);
            if (object != null && object instanceof SiteAwareAmetysObject)
            {
                return ((SiteAwareAmetysObject) object).getSite();
            }
        }
        else
        {
            AmetysObject ao = (AmetysObject) args.get("object");
            if (ao != null && ao instanceof SiteAwareAmetysObject)
            {
                return ((SiteAwareAmetysObject) ao).getSite();
            }
        }

        return null;
    }
    
    /**
     * Set the population context attribute from the given site in the request
     * @param request the request
     * @param site the site. Can be null. In this case, take the site in the request
     */
    public static void setPopulationContextAttribute(Request request, Site site)
    {
        String siteName = site != null ? site.getName() : getSiteName(request);
        if (StringUtils.isNotBlank(siteName))
        {
            // Set the site name into the request for the other components to be able to retrieve it.
            request.setAttribute("siteName", siteName);
            
            List<String> populationContexts = new ArrayList<>();
            
            // Set the population contexts to be able to get allowed users
            populationContexts.add("/sites/" + siteName);
            populationContexts.add("/sites-fo/" + siteName);
            
            request.setAttribute(PopulationContextHelper.POPULATION_CONTEXTS_REQUEST_ATTR, populationContexts);
        }
    }
}