content: /*
   * Copyright 2021-2024 Aklivity Inc.
   *
   * Aklivity 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 io.aklivity.zilla.runtime.binding.http.config;
  
  import static java.util.function.Function.identity;
  
  import java.util.Set;
  import java.util.regex.Matcher;
  
  public final class HttpAllowConfig
  {
      public final Set<String> origins;
      public final Set<String> methods;
      public final Set<String> headers;
      public final boolean credentials;
  
      private final Set<String> implicitOrigins;
  
      public static HttpAllowConfigBuilder<HttpAllowConfig> builder()
      {
          return new HttpAllowConfigBuilder<>(identity());
      }
  
      HttpAllowConfig(
          Set<String> origins,
          Set<String> methods,
          Set<String> headers,
          boolean credentials)
      {
          this.origins = origins;
          this.implicitOrigins = origins != null ? HttpAccessControlConfig.asImplicitOrigins(origins) : null;
          this.methods = methods;
          this.headers = headers != null ? HttpAccessControlConfig.asCaseless(headers) : null;
          this.credentials = credentials;
      }
  
      boolean origin(
          String origin)
      {
          return origins == null ||
                 origins.contains(origin) ||
                 implicitOrigins.contains(origin);
      }
  
      boolean method(
          String method)
      {
          return methods == null ||
                 methods.contains(method);
      }
  
      boolean headers(
          String headers)
      {
          return headers == null ||
                 headersMatch(headers);
      }
  
      private boolean headersMatch(
          String headers)
      {
          int match = 0;
  
          Matcher matchHeaders = HttpAccessControlConfig.HEADERS_MATCHER.get().reset(headers);
          while (matchHeaders.find())
          {
              if (header(matchHeaders.group(1)))
              {
                  match++;
              }
          }
  
          return match > 0;
      }
  
      private boolean header(
          String header)
      {
          return headers == null ||
                 headers.contains(header);
      }
  
      boolean originExplicit()
      {
          return credentials || origins != null;
      }
  
      boolean methodsExplicit()
      {
          return credentials || methods != null;
      }
  
      boolean headersExplicit()
      {
          return credentials || headers != null;
      }
  
      boolean credentialsExplicit()
      {
          return credentials;
      }
  }
  