/*
    * 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.syncope.sra.security.saml2;
  
  import java.net.URI;
  import org.apache.syncope.sra.security.PublicRouteMatcher;
  import org.apache.syncope.sra.session.SessionUtils;
  import org.springframework.http.HttpStatus;
  import org.springframework.security.web.server.util.matcher.ServerWebExchangeMatcher;
  import org.springframework.security.web.server.util.matcher.ServerWebExchangeMatchers;
  import org.springframework.web.server.ServerWebExchange;
  import org.springframework.web.server.WebFilter;
  import org.springframework.web.server.WebFilterChain;
  import reactor.core.publisher.Mono;
  
  public class SAML2AnonymousWebFilter implements WebFilter {
  
      private final ServerWebExchangeMatcher matcher;
  
      public SAML2AnonymousWebFilter(final PublicRouteMatcher publicRouteMatcher) {
          this.matcher = ServerWebExchangeMatchers.matchers(
                  publicRouteMatcher,
                  SessionUtils.authInSession(),
                  SAML2LogoutResponseWebFilter.MATCHER);
      }
  
      @Override
      public Mono<Void> filter(final ServerWebExchange exchange, final WebFilterChain chain) {
          return matcher.matches(exchange).
                  filter(matchResult -> !matchResult.isMatch()).
                  switchIfEmpty(chain.filter(exchange).then(Mono.empty())).
                  flatMap(r -> exchange.getSession()).
                  flatMap(session -> {
                      session.getAttributes().put(SessionUtils.INITIAL_REQUEST_URI, exchange.getRequest().getURI());
  
                      exchange.getResponse().setStatusCode(HttpStatus.SEE_OTHER);
                      exchange.getResponse().getHeaders().
                              setLocation(URI.create(SAML2WebSsoAuthenticationRequestWebFilter.AUTHENTICATE_URL));
                      return exchange.getResponse().setComplete();
                  });
      }
  }