/*
 * Copyright (c) 2010-2012 Lockheed Martin Corporation
 *
 * 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.eurekastreams.server.action.execution.notification.translator;

import java.util.List;

import org.eurekastreams.server.action.execution.notification.NotificationBatch;
import org.eurekastreams.server.action.execution.notification.NotificationPropertyKeys;
import org.eurekastreams.server.action.request.notification.ActivityNotificationsRequest;
import org.eurekastreams.server.domain.NotificationType;
import org.eurekastreams.server.domain.stream.ActivityDTO;
import org.eurekastreams.server.persistence.mappers.DomainMapper;
import org.eurekastreams.server.search.modelview.DomainGroupModelView;
import org.eurekastreams.server.search.modelview.PersonModelView;
import org.eurekastreams.server.service.utility.ui.UiUrlBuilder;

/**
 * Translates the event of someone posting to a group stream to appropriate notifications.
 */
public class PostGroupStreamTranslator implements NotificationTranslator<ActivityNotificationsRequest>
{
    /** DAO to get group coordinator ids. */
    private final DomainMapper<Long, List<Long>> coordinatorDAO;

    /** DAO to get all group subscriber ids. */
    private final DomainMapper<Long, List<Long>> allSubscriberDAO;

    /** DAO to get unrestricted group subscriber ids. */
    private final DomainMapper<Long, List<Long>> unrestrictedSubscriberDAO;

    /**
     * Constructor.
     * 
     * @param inCoordinatorDAO
     *            DAO to get group coordinator ids.
     * @param inAllSubscriberDAO
     *            DAO to get all group subscriber ids.
     * @param inUnrestrictedSubscriberDAO
     *            DAO to get unrestricted group subscriber ids.
     */
    public PostGroupStreamTranslator(final DomainMapper<Long, List<Long>> inCoordinatorDAO,
            final DomainMapper<Long, List<Long>> inAllSubscriberDAO,
            final DomainMapper<Long, List<Long>> inUnrestrictedSubscriberDAO)
    {
        coordinatorDAO = inCoordinatorDAO;
        allSubscriberDAO = inAllSubscriberDAO;
        unrestrictedSubscriberDAO = inUnrestrictedSubscriberDAO;
    }

    /**
     * {@inheritDoc}
     */
    public NotificationBatch translate(final ActivityNotificationsRequest inRequest)
    {
        // determine if actor is a group coordinator to whether to get all subscribers or only those who subscribed
        // to all notifications (unrestricted)
        boolean fromCoord = coordinatorDAO.execute(inRequest.getTargetEntityId()).contains(inRequest.getActorId());
        DomainMapper<Long, List<Long>> subscriberDAO = fromCoord ? allSubscriberDAO : unrestrictedSubscriberDAO;

        // NOTE: This code assumes that the DAO returns a list which can be safely altered, specifically that it
        // supports removing elements and is not used elsewhere (e.g. stored off).
        List<Long> idsToNotify = subscriberDAO.execute(inRequest.getTargetEntityId());
        idsToNotify.remove(inRequest.getActorId());

        if (idsToNotify.isEmpty())
        {
            return null;
        }

        NotificationBatch batch = new NotificationBatch(NotificationType.POST_TO_FOLLOWED_STREAM, idsToNotify);
        batch.setProperty(NotificationPropertyKeys.ACTOR, PersonModelView.class, inRequest.getActorId());
        batch.setProperty("stream", DomainGroupModelView.class, inRequest.getTargetEntityId());
        batch.setProperty("activity", ActivityDTO.class, inRequest.getActivityId());
        batch.setPropertyAlias(NotificationPropertyKeys.SOURCE, "stream");
        batch.setProperty(NotificationPropertyKeys.URL, UiUrlBuilder.relativeUrlForActivity(inRequest.getActivityId()));
        return batch;
    }
}