/*
    * Copyright 2017 LINE Corporation
    *
    * LINE Corporation 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:
    *
    *   https://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 com.linecorp.centraldogma.server.internal.admin.auth;
  
  import static java.util.Objects.requireNonNull;
  
  import javax.annotation.Nullable;
  
  import com.google.common.annotations.VisibleForTesting;
  
  import com.linecorp.armeria.common.RequestContext;
  import com.linecorp.armeria.server.ServiceRequestContext;
  import com.linecorp.centraldogma.common.Author;
  import com.linecorp.centraldogma.server.metadata.User;
  
  import io.netty.util.AttributeKey;
  
  /**
   * A utility class to manage a {@link User} and its {@link Author} instances of the current login user.
   */
  public final class AuthUtil {
  
      @VisibleForTesting
      public static final AttributeKey<User> CURRENT_USER =
              AttributeKey.valueOf(AuthUtil.class, "CURRENT_USER");
  
      public static Author currentAuthor(ServiceRequestContext ctx) {
          final User user = ctx.attr(CURRENT_USER);
          assert user != null;
          return user == User.DEFAULT ? Author.DEFAULT
                                      : new Author(user.name(), user.email());
      }
  
      public static Author currentAuthor() {
          return currentAuthor(RequestContext.current());
      }
  
      public static User currentUser(ServiceRequestContext ctx) {
          return ctx.attr(CURRENT_USER);
      }
  
      public static User currentUser() {
          return currentUser(RequestContext.current());
      }
  
      @Nullable
      public static User currentUserOrNull() {
          final ServiceRequestContext currentOrNull = ServiceRequestContext.currentOrNull();
          if (currentOrNull == null) {
              return null;
          }
          return currentUser(currentOrNull);
      }
  
      public static void setCurrentUser(ServiceRequestContext ctx, User currentUser) {
          requireNonNull(ctx, "ctx");
          requireNonNull(currentUser, "currentUser");
          ctx.setAttr(CURRENT_USER, currentUser);
      }
  
      private AuthUtil() {}
  }