/**
 * Copyright (c) Istituto Nazionale di Fisica Nucleare (INFN). 2006-2016
 *
 * 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.glite.security.voms.admin.operations.requests;

import org.glite.security.voms.admin.configuration.VOMSConfiguration;
import org.glite.security.voms.admin.error.IllegalStateException;
import org.glite.security.voms.admin.operations.AuthorizationResponse;
import org.glite.security.voms.admin.operations.CurrentAdmin;
import org.glite.security.voms.admin.persistence.model.VOMSGroup;
import org.glite.security.voms.admin.persistence.model.VOMSRole;
import org.glite.security.voms.admin.persistence.model.VOMSUser;
import org.glite.security.voms.admin.persistence.model.request.GroupScopeRequest;
import org.glite.security.voms.admin.persistence.model.request.Request;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public abstract class GroupManagerRoleHolderOperation<T extends Request> extends
  BaseHandleRequestOperation<T> {

  public static final Logger LOGGER = LoggerFactory
    .getLogger(GroupManagerRoleHolderOperation.class);

  public GroupManagerRoleHolderOperation(T request, DECISION decision) {

    super(request, decision);

  }

  @Override
  final protected AuthorizationResponse isAllowed() {

    CurrentAdmin admin = CurrentAdmin.instance();

    if (!admin.isVoUser()) {
      LOGGER.debug("Current admin has no corresponding VO user.");
      return super.isAllowed();
    }

    final VOMSUser user = admin.getVoUser();
    
    String groupManagerRoleName = VOMSConfiguration
      .instance().getGroupManagerRoleName();

    
    VOMSRole gmRole = findRoleByNameAllowNull(groupManagerRoleName);

    if (gmRole == null) {
      LOGGER.debug("{} role is not defined, falling back to ACL authz.",
        groupManagerRoleName);

      return super.isAllowed();
    }

    if (!(request instanceof GroupScopeRequest)) {
      throw new IllegalStateException(
        "This is a bug: this class should only be instantiated "
          + "to handle group scoped requests.");
    }

    GroupScopeRequest gr = (GroupScopeRequest) request;
    VOMSGroup requestGroup = findGroupByName(gr.getGroupName());
    
    if (requestGroup.isRootGroup()){
      return super.isAllowed();
    }
    
    if (!user.isMember(requestGroup)){
      return super.isAllowed();
    }
    
    if (!user.hasRole(requestGroup, gmRole)) {
      return super.isAllowed();
    }

    return AuthorizationResponse.permit();
  }

}