/*
* Copyright (c) 2010 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.profile;
import java.util.List;
import org.apache.commons.logging.Log;
import org.eurekastreams.commons.actions.ExecutionStrategy;
import org.eurekastreams.commons.actions.context.PrincipalActionContext;
import org.eurekastreams.commons.logging.LogFactory;
import org.eurekastreams.server.action.request.profile.GetFollowersFollowingRequest;
import org.eurekastreams.server.domain.FollowerStatusable;
import org.eurekastreams.server.domain.PagedSet;
import org.eurekastreams.server.domain.Follower.FollowerStatus;
import org.eurekastreams.server.domain.strategies.FollowerStatusPopulator;
import org.eurekastreams.server.persistence.mappers.DomainMapper;
/**
* Action to get the followers of a person.
*
*/
public class GetFollowingExecution implements ExecutionStrategy<PrincipalActionContext>
{
/** Logger. */
private final Log log = LogFactory.make();
/** Mapper to find the follower's id given their account id. */
private final DomainMapper<String, Long> getPersonIdByAccountIdMapper;
/** Mapper returning the ids of the entities being followed. */
private final DomainMapper<Long, List<Long>> idsMapper;
/** Mapper returning entities (people, groups) given their ids. */
private final DomainMapper<List<Long>, List<FollowerStatusable>> bulkModelViewMapper;
/**
* Populator for follower status of results.
*/
private final FollowerStatusPopulator<FollowerStatusable> followerStatusPopulator;
/**
* Constructor.
*
* @param inGetPersonIdByAccountIdMapper
* Mapper to find the follower's id given their account id.
* @param inIdsMapper
* Mapper returning the ids of the entities being followed.
* @param inBulkModelViewMapper
* Mapper returning entities (people, groups) given their ids.
* @param inFollowerStatusPopulator
* populates each PersonModelView with the current user's follow status
*/
public GetFollowingExecution(final DomainMapper<String, Long> inGetPersonIdByAccountIdMapper,
final DomainMapper<Long, List<Long>> inIdsMapper,
final DomainMapper<List<Long>, List<FollowerStatusable>> inBulkModelViewMapper,
final FollowerStatusPopulator<FollowerStatusable> inFollowerStatusPopulator)
{
getPersonIdByAccountIdMapper = inGetPersonIdByAccountIdMapper;
idsMapper = inIdsMapper;
bulkModelViewMapper = inBulkModelViewMapper;
followerStatusPopulator = inFollowerStatusPopulator;
}
/**
* Returns Set of people following a user excluding themselves.
*
* @param inActionContext
* The action context.
* @return true if the group exists and the user is authorized, false otherwise
*/
@Override
public PagedSet<FollowerStatusable> execute(final PrincipalActionContext inActionContext)
{
// get the request
GetFollowersFollowingRequest inRequest = (GetFollowersFollowingRequest) inActionContext.getParams();
// get the unique entity Id
final String entityUniqueId = inRequest.getEntityId();
final long currentUserId = inActionContext.getPrincipal().getId();
Long entityId = getPersonIdByAccountIdMapper.execute(entityUniqueId);
List<Long> allIds = idsMapper.execute(entityId);
// determine the page
int startIndex = (inRequest.getStartIndex()).intValue();
int endIndex = (inRequest.getEndIndex()).intValue();
PagedSet<FollowerStatusable> pagedSet;
if (allIds.isEmpty())
{
pagedSet = new PagedSet<FollowerStatusable>();
}
else if (startIndex >= allIds.size())
{
// if asking for a range beyond the end of the list return an empty set
pagedSet = new PagedSet<FollowerStatusable>();
pagedSet.setTotal(allIds.size());
}
else
{
if (endIndex >= allIds.size())
{
endIndex = allIds.size() - 1;
}
List<Long> pageIds = allIds.subList(startIndex, endIndex + 1);
List<FollowerStatusable> list = bulkModelViewMapper.execute(pageIds);
followerStatusPopulator.execute(currentUserId, list, FollowerStatus.NOTSPECIFIED);
pagedSet = new PagedSet<FollowerStatusable>(startIndex, endIndex, allIds.size(), list);
}
if (log.isTraceEnabled())
{
log.trace("Retrieved " + pagedSet.getFromIndex() + " to " + pagedSet.getToIndex() + " of "
+ pagedSet.getTotal() + " following for person " + entityUniqueId);
}
return pagedSet;
}
}