/*
 * Copyright (C) 2003-2007 eXo Platform SAS.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Affero General Public License
 * as published by the Free Software Foundation; either version 3
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see<http://www.gnu.org/licenses/>.
 */

package org.etk.core.security;

import java.util.Collection;
import java.util.HashSet;
import java.util.Set;

import javax.security.auth.Subject;

/**
 * User Session encapsulates user's
 * principals such as name, groups along with JAAS subject (useful in J2EE
 * environment) as well as other optional attributes
 * 
 */

public class Identity {

  /**
   * User's identifier.
   */
  private String userId;

  /**
   * Memberships.
   */
  private Collection<MembershipEntry> memberships;

  /**
   * javax.security.auth.Subject can be used for logout process. <code>
   * LoginContext ctx = new LoginContext("exo-domain", subject);
   * ctx.logout();
   * </code>
   */
  private Subject subject;

  /**
   * User's roles.
   */
  private Collection<String> roles;

  /**
   * @param userId the iser's identifier.
   */
  public Identity(String userId) {
    this(userId, new HashSet<MembershipEntry>(), new HashSet<String>());
  }

  /**
   * @param userId the user's identifier.
   * @param memberships the memberships.
   */
  public Identity(String userId, Collection<MembershipEntry> memberships) {
    this(userId, memberships, new HashSet<String>());
  }

  /**
   * @param userId the user's identifier.
   * @param memberships the memberships.
   * @param roles the user's roles.
   */
  public Identity(String userId, Collection<MembershipEntry> memberships, Collection<String> roles) {
    this.userId = userId;
    this.memberships = memberships;
    this.roles = roles;
  }

  /**
   * @return user name.
   */
  public String getUserId() {
    return userId;
  }

  /**
   * @param group the group.
   * @param membershipType the MembershipType.
   * @return true if user has given membershipType for given group, false
   *         otherwise
   */
  public boolean isMemberOf(String group, String membershipType) {
    return containsMembership(new MembershipEntry(group, membershipType));
  }

  /**
   * @param me the MembershipEntry.
   * @return true if user has given MembershipEntry, false otherwise.
   */
  public boolean isMemberOf(MembershipEntry me) {
    return containsMembership(me);
  }

  /**
   * Check is user member of group.
   * 
   * @param group the group.
   * @return true if user has any membershipType for given group, false
   *         otherwise.
   */
  public boolean isMemberOf(String group) {
    return containsMembership(new MembershipEntry(group));
  }

  /**
   * @return set of groups to which this user belongs to.
   */
  public Set<String> getGroups() {
    Set<String> groups = new HashSet<String>();
    for (MembershipEntry m : memberships) {
      groups.add(m.getGroup());
    }
    return groups;
  }

  /**
   * @deprecated for back compatibility.
   */
  public void setMemberships(Collection<MembershipEntry> memberships) {
    this.memberships = memberships;
  }

  /**
   * @return user's memberships.
   */
  public Collection<MembershipEntry> getMemberships() {
    return memberships;
  }

  /**
   * Sets the roles for J2EE environment using.
   * 
   * @param roles the roles.
   */
  public void setRoles(Collection<String> roles) {
    this.roles = roles;
  }

  /**
   * @return roles users'roles.
   */
  public Collection<String> getRoles() {
    return roles;
  }

  /**
   * @return @see {@link Subject} .
   */
  public Subject getSubject() {
    return subject;
  }

  /**
   * @param subject @see {@link Subject} .
   */
  public void setSubject(Subject subject) {
    this.subject = subject;
  }

  /**
   * Check is given {@link MembershipEntry} presents in user's memberships.
   * 
   * @param checkMe the MembershipEntry.
   * @return true if presents false otherwise.
   */
  private boolean containsMembership(MembershipEntry checkMe) {
    for (MembershipEntry membership : memberships) {
      if (checkMe.equals(membership))
        return true;
    }
    return false;
  }

}