/*
    * Copyright 2019 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.metadata;
  
  import static java.util.Objects.requireNonNull;
  
  import java.io.Serializable;
  import java.util.List;
  
  import com.fasterxml.jackson.annotation.JsonCreator;
  import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
  import com.fasterxml.jackson.annotation.JsonInclude;
  import com.fasterxml.jackson.annotation.JsonInclude.Include;
  import com.fasterxml.jackson.annotation.JsonProperty;
  import com.google.common.base.MoreObjects;
  import com.google.common.base.Strings;
  import com.google.common.collect.ImmutableList;
  
  import com.linecorp.centraldogma.internal.Util;
  
  /**
   * A user.
   */
  @JsonIgnoreProperties(ignoreUnknown = true)
  @JsonInclude(Include.NON_NULL)
  public class User implements Identifiable, Serializable {
  
      private static final long serialVersionUID = -5429782019985526549L;
  
      private static final String LEVEL_USER_STR = "LEVEL_USER";
      private static final String LEVEL_SYSTEM_ADMIN_STR = "LEVEL_SYSTEM_ADMIN";
  
      // System-wide roles for a user. It is different from the role in a project.
      public static final List<String> LEVEL_USER = ImmutableList.of(LEVEL_USER_STR);
      public static final List<String> LEVEL_SYSTEM_ADMIN =
              ImmutableList.of(LEVEL_SYSTEM_ADMIN_STR, LEVEL_USER_STR);
  
      public static final User DEFAULT = new User("user@localhost.localdomain", LEVEL_USER);
      public static final User SYSTEM_ADMIN = new User("admin@localhost.localdomain", LEVEL_SYSTEM_ADMIN);
      public static final User SYSTEM = new User("system@localhost.localdomain", LEVEL_SYSTEM_ADMIN);
  
      private final String login;
      private final String name;
      private final String email;
      private final List<String> roles;
  
      private final boolean isSystemAdmin;
  
      /**
       * Creates a new instance.
       */
      @JsonCreator
      public User(@JsonProperty("login") String login,
                  @JsonProperty("name") String name,
                  @JsonProperty("email") String email,
                  @JsonProperty("roles") List<String> roles) {
          this.login = requireNonNull(login, "login");
          this.name = requireNonNull(name, "name");
          this.email = requireNonNull(email, "email");
          this.roles = ImmutableList.copyOf(requireNonNull(roles, "roles"));
          isSystemAdmin = roles.stream().anyMatch(LEVEL_SYSTEM_ADMIN_STR::equals);
      }
  
      /**
       * Creates a new instance.
       */
      public User(String login) {
          this(login, LEVEL_USER);
      }
  
      /**
       * Creates a new instance.
       */
      public User(String login, List<String> roles) {
          if (Strings.isNullOrEmpty(login)) {
              throw new IllegalArgumentException("login");
          }
          requireNonNull(roles, "roles");
  
          this.login = login;
          email = Util.toEmailAddress(login, "login");
          name = Util.emailToUsername(email, "login");
  
          this.roles = ImmutableList.copyOf(roles);
          isSystemAdmin = roles.stream().anyMatch(LEVEL_SYSTEM_ADMIN_STR::equals);
     }
 
     /**
      * Returns the login ID of the user.
      */
     @JsonProperty
     public String login() {
         return login;
     }
 
     /**
      * Returns the human friendly name of the user.
      */
     @JsonProperty
     public String name() {
         return name;
     }
 
     /**
      * Returns the e-mail address of the user.
      */
     @JsonProperty
     public String email() {
         return email;
     }
 
     /**
      * Returns the roles of the user.
      */
     @JsonProperty
     public List<String> roles() {
         return roles;
     }
 
     @Override
     public String id() {
         return email();
     }
 
     /**
      * Returns {@code true} if this user has system administrative privileges.
      */
     public boolean isSystemAdmin() {
         return isSystemAdmin;
     }
 
     @Override
     public boolean equals(Object o) {
         if (this == o) {
             return true;
         }
         if (o == null || getClass() != o.getClass()) {
             return false;
         }
 
         final User user = (User) o;
         return login.equals(user.login);
     }
 
     @Override
     public int hashCode() {
         return login.hashCode();
     }
 
     @Override
     public String toString() {
         return MoreObjects.toStringHelper(this)
                           .add("login", login())
                           .add("name", name())
                           .add("email", email())
                           .add("roles", roles())
                           .add("isSystemAdmin", isSystemAdmin())
                           .toString();
     }
 }