/**
 * Licensed to Apereo under one or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information regarding copyright ownership. Apereo
 * licenses this file to you 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 the
 * following location:
 *
 * <p>http://www.apache.org/licenses/LICENSE-2.0
 *
 * <p>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.apereo.portal.groups;

import java.util.Set;
import javax.naming.Name;

/**
 * An <code>IEntityGroup</code> is a composite, or non-leaf <code>IGroupMember</code>. It contains
 * <code>IEntities</code> and other <code>IEntityGroups</code>.
 *
 * <p>The api defines methods for adding a member to, and removing it from, a group, though not vice
 * versa. (Although there is nothing to prevent a given <code>IGroupMember</code> implementation
 * from storing references to its containing groups.) These methods only change the group structure
 * in memory.
 *
 * <p><code>addChild(IGroupMember gm)</code><br>
 * <code>removeChild(IGroupMember gm)</code><br>
 *
 * <p>The following methods commit changes in the group structure to the persistent store:
 *
 * <p><code>delete()</code> - delete the group and its memberships<br>
 * <code>update()</code> - insert or update the group, as appropriate<br>
 * <code>updateMembers()</code> - insert/update/delete group memberships as appropriate<br>
 *
 * <p>The following methods were added to permit an <code>IEntityGroup</code> to function within a
 * composite group service:
 *
 * <p><code>getLocalKey()</code> - returns the key within the service of origin.<br>
 * <code>getServiceName()</code> - returns the Name of the group service of origin.<br>
 * <code>setLocalGroupService()</code> - sets the group service of origin.<br>
 *
 * <p>
 *
 */
public interface IEntityGroup extends IGroupMember {

    /**
     * Answers if this <code>IGroupMember</code> has any members.
     *
     * @return boolean
     */
    boolean hasMembers() throws GroupsException;

    /** Answers if <code>IGroupMember</code> gm is a member of <code>this</code>. */
    boolean contains(IGroupMember gm) throws GroupsException;

    /**
     * Answers if <code>IGroupMember</code> gm is a recursive member of <code>this</code>.
     *
     * @return boolean
     * @param gm org.apereo.portal.groups.IGroupMember
     */
    boolean deepContains(IGroupMember gm) throws GroupsException;

    /** Returns a collection of this <code>IGroupMember's</code> children. */
    Set<IGroupMember> getChildren() throws GroupsException;

    /**
     * Returns a collection of this <code>IGroupMember's</code> recursively-retrieved <code>
     * IGroupMembers</code>.
     */
    Set<IGroupMember> getDescendants() throws GroupsException;

    /**
     * Adds <code>IGroupMember</code> gm to this group, but does not commit it to the data store.
     * Use <code>updateMembers()</code> to commit memberships to the data store.
     *
     * @param gm org.apereo.portal.groups.IGroupMember
     * @exception GroupsException is thrown if the member is a group and this group already has a
     *     group with the same name or if the addition of the group creates a circular reference.
     */
    void addChild(IGroupMember gm) throws GroupsException;

    /**
     * Deletes the <code>IEntityGroup</code> from the data store.
     *
     * @exception GroupsException if the delete cannot be performed.
     */
    void delete() throws GroupsException;
    /**
     * Returns the name of the group creator. May be null.
     *
     * @return String
     */
    String getCreatorID();
    /**
     * Returns the group description, which may be null.
     *
     * @return String
     */
    String getDescription();
    /**
     * Returns the key from the group service of origin.
     *
     * @return String
     */
    String getLocalKey();
    /**
     * Returns the group name.
     *
     * @return String
     */
    String getName();
    /**
     * Returns the Name of the group service of origin.
     *
     * @return String
     */
    Name getServiceName();
    /**
     * Answers if this <code>IEntityGroup</code> can be changed or deleted.
     *
     * @return boolean
     * @exception GroupsException
     */
    boolean isEditable() throws GroupsException;
    /**
     * Removes the <code>IGroupMember</code> from this group, but does not remove the membership
     * from the data store.
     *
     * @param gm org.apereo.portal.groups.IGroupMember
     */
    void removeChild(IGroupMember gm) throws GroupsException;
    /** @param userID String (required) */
    void setCreatorID(String userID);
    /** @param name String (may be null) */
    void setDescription(String name);
    /**
     * Sets the group name which must be unique within any of its containing groups.
     *
     * @param name String
     * @exception GroupsException
     */
    void setName(String name) throws GroupsException;
    /**
     * Commit the <code>IEntityGroup</code> AND ITS MEMBERSHIPS to the data store.
     *
     * @exception GroupsException if the update cannot be performed.
     */
    void update() throws GroupsException;
    /**
     * Commit this <code>IEntityGroup's</code> memberships to the data store.
     *
     * @exception GroupsException if the update cannot be performed.
     */
    void updateMembers() throws GroupsException;

    /** Sets the group service of origin. */
    void setLocalGroupService(IIndividualGroupService groupService) throws GroupsException;
}