/*
    * Copyright 2014 The Netty Project
    *
    * The Netty Project 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 io.netty.handler.codec.mqtt;
  
  import io.netty.handler.codec.DecoderResult;
  import io.netty.util.internal.StringUtil;
  
  /**
   * Base class for all MQTT message types.
   */
  public class MqttMessage {
  
      private final MqttFixedHeader mqttFixedHeader;
      private final Object variableHeader;
      private final Object payload;
      private final DecoderResult decoderResult;
  
      // Constants for fixed-header only message types with all flags set to 0 (see
      // https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html#_Table_2.2_-)
      public static final MqttMessage PINGREQ = new MqttMessage(new MqttFixedHeader(MqttMessageType.PINGREQ, false,
              MqttQoS.AT_MOST_ONCE, false, 0));
  
      public static final MqttMessage PINGRESP = new MqttMessage(new MqttFixedHeader(MqttMessageType.PINGRESP, false,
              MqttQoS.AT_MOST_ONCE, false, 0));
  
      public static final MqttMessage DISCONNECT = new MqttMessage(new MqttFixedHeader(MqttMessageType.DISCONNECT, false,
              MqttQoS.AT_MOST_ONCE, false, 0));
  
      public MqttMessage(MqttFixedHeader mqttFixedHeader) {
          this(mqttFixedHeader, null, null);
      }
  
      public MqttMessage(MqttFixedHeader mqttFixedHeader, Object variableHeader) {
          this(mqttFixedHeader, variableHeader, null);
      }
  
      public MqttMessage(MqttFixedHeader mqttFixedHeader, Object variableHeader, Object payload) {
          this(mqttFixedHeader, variableHeader, payload, DecoderResult.SUCCESS);
      }
  
      public MqttMessage(
              MqttFixedHeader mqttFixedHeader,
              Object variableHeader,
              Object payload,
              DecoderResult decoderResult) {
          this.mqttFixedHeader = mqttFixedHeader;
          this.variableHeader = variableHeader;
          this.payload = payload;
          this.decoderResult = decoderResult;
      }
  
      public MqttFixedHeader fixedHeader() {
          return mqttFixedHeader;
      }
  
      public Object variableHeader() {
          return variableHeader;
      }
  
      public Object payload() {
          return payload;
      }
  
      public DecoderResult decoderResult() {
          return decoderResult;
      }
  
      @Override
      public String toString() {
          return new StringBuilder(StringUtil.simpleClassName(this))
              .append('[')
              .append("fixedHeader=").append(fixedHeader() != null ? fixedHeader().toString() : "")
              .append(", variableHeader=").append(variableHeader() != null ? variableHeader.toString() : "")
              .append(", payload=").append(payload() != null ? payload.toString() : "")
              .append(']')
              .toString();
      }
  }