/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF 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
 *
 *   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.apache.fineract.cn.anubis.security;

import org.apache.fineract.cn.lang.ApplicationName;
import org.slf4j.Logger;
import org.springframework.security.access.AccessDecisionVoter;
import org.springframework.security.access.ConfigAttribute;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.web.FilterInvocation;

import java.util.Collection;
import java.util.Optional;

/**
 * @author Myrle Krantz
 */
public class UrlPermissionChecker implements AccessDecisionVoter<FilterInvocation> {
  private final Logger logger;
  private final ApplicationName applicationName;

  public UrlPermissionChecker(final Logger logger, final ApplicationName applicationName) {
    this.logger = logger;
    this.applicationName = applicationName;
  }

  @Override public boolean supports(final ConfigAttribute attribute) {
    return attribute.getAttribute().equals(ApplicationPermission.URL_AUTHORITY);
  }

  @Override public boolean supports(final Class<?> clazz) {
    return FilterInvocation.class.isAssignableFrom(clazz);
  }

  @Override public int vote(
      final Authentication unAuthentication,
      final FilterInvocation filterInvocation,
      final Collection<ConfigAttribute> attributes) {
    if (!AnubisAuthentication.class.isAssignableFrom(unAuthentication.getClass()))
      return ACCESS_ABSTAIN;

    if (filterInvocation == null)
      return ACCESS_ABSTAIN;

    final AnubisAuthentication authentication = (AnubisAuthentication) unAuthentication;

    final Collection<? extends GrantedAuthority> authorities = authentication.getAuthorities();
    final Optional<ApplicationPermission> matchedPermission = authorities.stream()
            .map(x -> (ApplicationPermission) x)
            .filter(x -> x.matches(filterInvocation, applicationName, authentication.getPrincipal()))
            .findAny();

    //Do not put full .getRequestUrl() into log info, because in the case of identity, it includes the password.
    matchedPermission.ifPresent(x -> logger.debug("Authorizing access to {} based on permission: {}"
            , filterInvocation.getRequest().getServletPath(),  x));

    return matchedPermission.map(x -> ACCESS_GRANTED).orElse(ACCESS_DENIED);
  }
}