/*
 * Copyright (c) 2004-2022, University of Oslo
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * Neither the name of the HISP project nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.hisp.dhis.security.vote;

import com.opensymphony.xwork2.config.entities.ActionConfig;
import java.util.Collection;
import java.util.Collections;
import java.util.Set;
import lombok.extern.slf4j.Slf4j;
import org.springframework.security.access.ConfigAttribute;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.GrantedAuthority;

/**
 * AccessDecisionVoter which grants access if one of the granted authorities matches attribute
 * prefix + module name. The module name is taken from an <code>
 * com.opensymphony.xwork.config.entities.ActionConfig</code> object, which is the only type of
 * object this voter supports.
 *
 * @author Torgeir Lorange Ostby
 * @version $Id: ModuleAccessVoter.java 6352 2008-11-20 15:49:52Z larshelg $
 */
@Slf4j
public class ModuleAccessVoter extends AbstractPrefixedAccessDecisionVoter {
  // -------------------------------------------------------------------------
  // Configuration
  // -------------------------------------------------------------------------

  private Set<String> alwaysAccessible = Collections.emptySet();

  /** Sets a set of names for modules which are always accessible. */
  public void setAlwaysAccessible(Set<String> alwaysAccessible) {
    this.alwaysAccessible = alwaysAccessible;
  }

  // -------------------------------------------------------------------------
  // AccessDecisionVoter implementation
  // -------------------------------------------------------------------------

  /**
   * Returns true if the class equals <code>com.opensymphony.xwork.config.entities.ActionConfig
   * </code>. False otherwise.
   */
  @Override
  public boolean supports(Class<?> clazz) {
    boolean result = ActionConfig.class.equals(clazz);

    log.debug("Supports class: " + clazz + ", " + result);

    return result;
  }

  /**
   * Votes. Votes ACCESS_ABSTAIN if the object class is not supported. Votes ACCESS_GRANTED if there
   * is a granted authority which equals attribute prefix + module name, or the module name is in
   * the always accessible set. Otherwise votes ACCESS_DENIED.
   */
  @Override
  public int vote(
      Authentication authentication, Object object, Collection<ConfigAttribute> attributes) {
    if (!supports(object.getClass())) {
      log.debug("ACCESS_ABSTAIN [" + object.toString() + "]: Class not supported.");

      return ACCESS_ABSTAIN;
    }

    ActionConfig target = (ActionConfig) object;

    if (alwaysAccessible.contains(target.getPackageName())) {
      log.debug("ACCESS_GRANTED [" + target.getPackageName() + "] by configuration.");

      return ACCESS_GRANTED;
    }

    String requiredAuthority = attributePrefix + target.getPackageName();

    for (GrantedAuthority grantedAuthority : authentication.getAuthorities()) {
      if (grantedAuthority.getAuthority().equals(requiredAuthority)) {
        log.debug("ACCESS_GRANTED [" + target.getPackageName() + "]");

        return ACCESS_GRANTED;
      }
    }

    log.debug("ACCESS_DENIED [" + target.getPackageName() + "]");

    return ACCESS_DENIED;
  }
}
