/*
 * This library is part of OpenCms -
 * the Open Source Content Management System
 *
 * Copyright (c) Alkacon Software GmbH (http://www.alkacon.com)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * For further information about Alkacon Software GmbH, please see the
 * company website: http://www.alkacon.com
 *
 * For further information about OpenCms, please see the
 * project website: http://www.opencms.org
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package org.opencms.security;

import org.opencms.db.CmsSecurityManager;
import org.opencms.file.CmsGroup;
import org.opencms.file.CmsObject;
import org.opencms.file.CmsResource;
import org.opencms.file.CmsResourceFilter;
import org.opencms.file.CmsUser;
import org.opencms.main.CmsException;
import org.opencms.main.OpenCms;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Set;

import com.google.common.collect.Lists;

/**
 * This manager provide access to the role related operations.<p>
 *
 * @since 6.5.6
 */
public class CmsRoleManager {

    /** The security manager. */
    private final CmsSecurityManager m_securityManager;

    /**
     * Default constructor.<p>
     *
     * @param securityManager the security manager
     */
    public CmsRoleManager(CmsSecurityManager securityManager) {

        m_securityManager = securityManager;
    }

    /**
     * Adds a user to the given role.<p>
     *
     * @param cms the opencms context
     * @param role the role
     * @param username the name of the user that is to be added to the role
     *
     * @throws CmsException if something goes wrong
     */
    public void addUserToRole(CmsObject cms, CmsRole role, String username) throws CmsException {

        m_securityManager.addUserToGroup(cms.getRequestContext(), username, role.getGroupName(), true);
    }

    /**
     * Checks if the user of this OpenCms context is a member of the given role
     * for the given organizational unit.<p>
     *
     * The user must have the given role in at least one parent organizational unit.<p>
     *
     * @param cms the opencms context
     * @param role the role to check
     *
     * @throws CmsRoleViolationException if the user does not have the required role permissions
     */
    public void checkRole(CmsObject cms, CmsRole role) throws CmsRoleViolationException {

        m_securityManager.checkRole(cms.getRequestContext(), role);
    }

    /**
     * Checks if the user of this OpenCms context is a member of the given role
     * for the given resource.<p>
     *
     * The user must have the given role in at least one organizational unit to which this resource belongs.<p>
     *
     * @param cms the opencms context
     * @param role the role to check
     * @param resourceName the name of the resource to check the role for
     *
     * @throws CmsRoleViolationException if the user does not have the required role permissions
     * @throws CmsException if something goes wrong, while reading the resource
     */
    public void checkRoleForResource(CmsObject cms, CmsRole role, String resourceName)
    throws CmsException, CmsRoleViolationException {

        CmsResource resource = cms.readResource(resourceName);
        m_securityManager.checkRoleForResource(cms.getRequestContext(), role, resource);
    }

    /**
     * Returns all groups of organizational units for which the current user
     * has the {@link CmsRole#ACCOUNT_MANAGER} role.<p>
     *
     * @param cms the current cms context
     * @param ouFqn the fully qualified name of the organizational unit
     * @param includeSubOus if sub organizational units should be included in the search
     *
     * @return a list of {@link org.opencms.file.CmsGroup} objects
     *
     * @throws CmsException if something goes wrong
     */
    public List<CmsGroup> getManageableGroups(CmsObject cms, String ouFqn, boolean includeSubOus) throws CmsException {

        List<CmsGroup> groups = new ArrayList<CmsGroup>();
        Iterator<CmsOrganizationalUnit> it = getOrgUnitsForRole(
            cms,
            CmsRole.ACCOUNT_MANAGER.forOrgUnit(ouFqn),
            includeSubOus).iterator();
        while (it.hasNext()) {
            CmsOrganizationalUnit orgUnit = it.next();
            groups.addAll(OpenCms.getOrgUnitManager().getGroups(cms, orgUnit.getName(), false));
        }
        return groups;
    }

    /**
     * Returns a list of those organizational units whose members can be managed by the current user.<p>
     *
     * @param cms the current CMS context
     * @param ouFqn the fully qualified name of the organizational unit
     * @param includeSubOus if sub organizational units should be included in the search
     * @param includeWebusers if webuser organizational units should be included in the search
     *
     * @return a list of organizational units
     *
     * @throws CmsException if something goes wrong
     */
    public List<CmsOrganizationalUnit> getManageableOrgUnits(
        CmsObject cms,
        String ouFqn,
        boolean includeSubOus,
        boolean includeWebusers) throws CmsException {

        List<CmsOrganizationalUnit> result = Lists.newArrayList();
        List<CmsOrganizationalUnit> ous = getOrgUnitsForRole(
            cms,
            CmsRole.ACCOUNT_MANAGER.forOrgUnit(ouFqn),
            includeSubOus);
        for (CmsOrganizationalUnit ou : ous) {
            if (includeWebusers || !ou.hasFlagWebuser()) {
                result.add(ou);
            }
        }
        return result;
    }

    /**
     * Returns all resources of organizational units for which the current user has
     * the given role role.<p>
     *
     * @param cms the current cms context
     * @param role the role to check
     *
     * @return a list of {@link org.opencms.file.CmsResource} objects
     *
     * @throws CmsException if something goes wrong
     */
    public List<CmsResource> getManageableResources(CmsObject cms, CmsRole role) throws CmsException {

        return m_securityManager.getManageableResources(cms.getRequestContext(), role);
    }

    /**
     * Returns all users of organizational units for which the current user has
     * the {@link CmsRole#ACCOUNT_MANAGER} role.<p>
     *
     * @param cms the current cms context
     * @param ouFqn the fully qualified name of the organizational unit
     * @param includeSubOus if sub organizational units should be included in the search
     *
     * @return a list of {@link org.opencms.file.CmsUser} objects
     *
     * @throws CmsException if something goes wrong
     */
    public List<CmsUser> getManageableUsers(CmsObject cms, String ouFqn, boolean includeSubOus) throws CmsException {

        return getManageableUsers(cms, ouFqn, includeSubOus, false);
    }

    /**
     * Returns all users of organizational units for which the current user has
     * the {@link CmsRole#ACCOUNT_MANAGER} role.<p>
     *
     * @param cms the current cms context
     * @param ouFqn the fully qualified name of the organizational unit
     * @param includeSubOus if sub organizational units should be included in the search
     * @param includeWebusers if webuser organizational units should be included in the search
     *
     * @return a list of {@link org.opencms.file.CmsUser} objects
     *
     * @throws CmsException if something goes wrong
     */
    public List<CmsUser> getManageableUsers(CmsObject cms, String ouFqn, boolean includeSubOus, boolean includeWebusers)
    throws CmsException {

        List<CmsOrganizationalUnit> ous = getManageableOrgUnits(cms, ouFqn, includeSubOus, includeWebusers);
        List<CmsUser> users = new ArrayList<CmsUser>();
        Iterator<CmsOrganizationalUnit> it = ous.iterator();
        while (it.hasNext()) {
            CmsOrganizationalUnit orgUnit = it.next();
            users.addAll(OpenCms.getOrgUnitManager().getUsers(cms, orgUnit.getName(), false));
        }
        return users;
    }

    /**
     * Returns all the organizational units for which the current user has the given role.<p>
     *
     * @param cms the current cms context
     * @param role the role to check
     * @param includeSubOus if sub organizational units should be included in the search
     *
     * @return a list of {@link org.opencms.security.CmsOrganizationalUnit} objects
     *
     * @throws CmsException if something goes wrong
     */
    public List<CmsOrganizationalUnit> getOrgUnitsForRole(CmsObject cms, CmsRole role, boolean includeSubOus)
    throws CmsException {

        return m_securityManager.getOrgUnitsForRole(cms.getRequestContext(), role, includeSubOus);
    }

    /**
     * Returns the groups which constitute a given role, i.e. the set of groups such that a member of any of them
     * has the given role.<p>
     *
     * @param cms the CMS context
     * @param role the role
     * @param directUsersOnly if true, only the role's direct group will be returned
     *
     * @return the groups constituting the given role
     *
     * @throws CmsException if something goes wrong
     */
    public Set<CmsGroup> getRoleGroups(CmsObject cms, CmsRole role, boolean directUsersOnly) throws CmsException {

        return m_securityManager.getRoleGroups(cms.getRequestContext(), role, directUsersOnly);
    }

    /**
     * Returns all roles, in the given organizational unit.<p>
     *
     * @param cms the opencms context
     * @param ouFqn the fully qualified name of the organizational unit of the role
     * @param includeSubOus include roles of child organizational units
     *
     * @return a list of all <code>{@link CmsRole}</code> objects
     *
     * @throws CmsException if operation was not successful
     */
    public List<CmsRole> getRoles(CmsObject cms, String ouFqn, boolean includeSubOus) throws CmsException {

        CmsOrganizationalUnit ou = OpenCms.getOrgUnitManager().readOrganizationalUnit(cms, ouFqn);
        List<CmsGroup> groups = m_securityManager.getGroups(cms.getRequestContext(), ou, includeSubOus, true);
        List<CmsRole> roles = new ArrayList<CmsRole>(groups.size());
        Iterator<CmsGroup> itGroups = groups.iterator();
        while (itGroups.hasNext()) {
            CmsGroup group = itGroups.next();
            roles.add(CmsRole.valueOf(group));
        }
        return roles;
    }

    /**
     * Returns all roles the given user has over the given resource.<p>
     *
     * @param cms the current cms context
     * @param user the user
     * @param resource the resource
     *
     * @return a list of {@link CmsRole} objects
     *
     * @throws CmsException if something goes wrong
     */
    public List<CmsRole> getRolesForResource(CmsObject cms, CmsUser user, CmsResource resource) throws CmsException {

        return m_securityManager.getRolesForResource(cms.getRequestContext(), user, resource);
    }

    /**
     * Returns all roles the given user has over the given resource.<p>
     *
     * @param cms the current cms context
     * @param userFqn the user name to check
     * @param resourceName the resource name
     *
     * @return a list of {@link CmsRole} objects
     *
     * @throws CmsException if something goes wrong
     */
    public List<CmsRole> getRolesForResource(CmsObject cms, String userFqn, String resourceName) throws CmsException {

        CmsUser user = cms.readUser(userFqn);
        CmsResource resource = cms.readResource(resourceName, CmsResourceFilter.ALL);
        return m_securityManager.getRolesForResource(cms.getRequestContext(), user, resource);
    }

    /**
     * Returns all roles the given user belongs to, in the given organizational unit.<p>
     *
     * @param cms the opencms context
     * @param username the name of the user to get all roles for
     * @param ouFqn the fully qualified name of the organizational unit to restrict the search to
     * @param includeChildOus include roles of child organizational units
     * @param directRolesOnly if set only the direct assigned roles will be returned, if not also indirect roles
     * @param recursive if this is set, also roles of higher organizational unit are considered
     *
     * @return a list of <code>{@link org.opencms.security.CmsRole}</code> objects
     *
     * @throws CmsException if operation was not successful
     */
    public List<CmsRole> getRolesOfUser(
        CmsObject cms,
        String username,
        String ouFqn,
        boolean includeChildOus,
        boolean directRolesOnly,
        boolean recursive) throws CmsException {

        List<CmsGroup> groups;
        ouFqn = CmsOrganizationalUnit.removeLeadingSeparator(ouFqn);
        if (!recursive) {
            groups = m_securityManager.getGroupsOfUser(
                cms.getRequestContext(),
                username,
                ouFqn,
                includeChildOus,
                true,
                directRolesOnly,
                cms.getRequestContext().getRemoteAddress());
        } else {
            groups = new ArrayList<CmsGroup>();
            Iterator<CmsGroup> itAllGroups = m_securityManager.getGroupsOfUser(
                cms.getRequestContext(),
                username,
                "",
                true,
                true,
                directRolesOnly,
                cms.getRequestContext().getRemoteAddress()).iterator();
            while (itAllGroups.hasNext()) {
                CmsGroup role = itAllGroups.next();
                if (!includeChildOus && role.getOuFqn().equals(ouFqn)) {
                    groups.add(role);
                }
                if (includeChildOus && role.getOuFqn().startsWith(ouFqn)) {
                    groups.add(role);
                }
            }
        }
        List<CmsRole> roles = new ArrayList<CmsRole>(groups.size());
        Iterator<CmsGroup> itGroups = groups.iterator();
        while (itGroups.hasNext()) {
            CmsGroup group = itGroups.next();
            roles.add(CmsRole.valueOf(group));
        }
        return roles;
    }

    /**
     * Returns all direct users of a given role, in the given organizational unit.<p>
     *
     * Users that are "indirectly" in the role are not returned in the result.<p>
     *
     * @param cms the opencms context
     * @param role the role to get all users for
     * @param includeOtherOuUsers include users of other organizational units
     * @param directUsersOnly if set only the direct assigned users will be returned,
     *                          if not also indirect users, ie. members of child groups
     *
     * @return all <code>{@link org.opencms.file.CmsUser}</code> objects in the group
     *
     * @throws CmsException if operation was not successful
     */
    public List<CmsUser> getUsersOfRole(
        CmsObject cms,
        CmsRole role,
        boolean includeOtherOuUsers,
        boolean directUsersOnly) throws CmsException {

        return m_securityManager.getUsersOfGroup(
            cms.getRequestContext(),
            role.getGroupName(),
            includeOtherOuUsers,
            directUsersOnly,
            true);
    }

    /**
     * Checks if the given context user has the given role in the given organizational unit.<p>
     *
     * @param cms the opencms context
     * @param role the role to check
     *
     * @return <code>true</code> if the given context user has the given role in the given organizational unit
     */
    public boolean hasRole(CmsObject cms, CmsRole role) {

        return m_securityManager.hasRole(cms.getRequestContext(), cms.getRequestContext().getCurrentUser(), role);
    }

    /**
     * Checks if the given user has the given role in the given organizational unit.<p>
     *
     * @param cms the opencms context
     * @param userName the name of the user to check the role for
     * @param role the role to check
     *
     * @return <code>true</code> if the given user has the given role in the given organizational unit
     */
    public boolean hasRole(CmsObject cms, String userName, CmsRole role) {

        CmsUser user;
        try {
            user = cms.readUser(userName);
        } catch (CmsException e) {
            // ignore
            return false;
        }
        return m_securityManager.hasRole(cms.getRequestContext(), user, role);
    }

    /**
     * Checks if the given context user has the given role for the given resource.<p>
     *
     * @param cms the opencms context
     * @param role the role to check
     * @param resourceName the name of the resource to check
     *
     * @return <code>true</code> if the given context user has the given role for the given resource
     */
    public boolean hasRoleForResource(CmsObject cms, CmsRole role, String resourceName) {

        CmsResource resource;
        try {
            resource = cms.readResource(resourceName, CmsResourceFilter.ALL);
        } catch (CmsException e) {
            // ignore
            return false;
        }
        return m_securityManager.hasRoleForResource(
            cms.getRequestContext(),
            cms.getRequestContext().getCurrentUser(),
            role,
            resource);
    }

    /**
     * Checks if the given context user has the given role for the given resource.<p>
     *
     * @param cms the opencms context
     * @param userName the name of the user to check the role for
     * @param role the role to check
     * @param resourceName the name of the resource to check
     *
     * @return <code>true</code> if the given context user has the given role for the given resource
     */
    public boolean hasRoleForResource(CmsObject cms, String userName, CmsRole role, String resourceName) {

        CmsResource resource;
        try {
            resource = cms.readResource(resourceName);
        } catch (CmsException e) {
            // ignore
            return false;
        }
        CmsUser user;
        try {
            user = cms.readUser(userName);
        } catch (CmsException e) {
            // ignore
            return false;
        }
        return m_securityManager.hasRoleForResource(cms.getRequestContext(), user, role, resource);
    }

    /**
     * Removes a user from a role, in the given organizational unit.<p>
     *
     * @param cms the opencms context
     * @param role the role to remove the user from
     * @param username the name of the user that is to be removed from the group
     *
     * @throws CmsException if operation was not successful
     */
    public void removeUserFromRole(CmsObject cms, CmsRole role, String username) throws CmsException {

        m_securityManager.removeUserFromGroup(cms.getRequestContext(), username, role.getGroupName(), true);
    }

}