/*
    * Copyright 2017 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 static io.netty.util.internal.ObjectUtil.checkPositive;
  
  import io.netty.buffer.ByteBuf;
  import io.netty.buffer.Unpooled;
  import io.netty.handler.codec.mqtt.MqttProperties.MqttPropertyType;
  import io.netty.util.CharsetUtil;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.List;
  
  public final class MqttMessageBuilders {
  
      public static final class PublishBuilder {
          private String topic;
          private boolean retained;
          private MqttQoS qos;
          private ByteBuf payload;
          private int messageId;
          private MqttProperties mqttProperties;
  
          PublishBuilder() {
          }
  
          public PublishBuilder topicName(String topic) {
              this.topic = topic;
              return this;
          }
  
          public PublishBuilder retained(boolean retained) {
              this.retained = retained;
              return this;
          }
  
          public PublishBuilder qos(MqttQoS qos) {
              this.qos = qos;
              return this;
          }
  
          public PublishBuilder payload(ByteBuf payload) {
              this.payload = payload;
              return this;
          }
  
          public PublishBuilder messageId(int messageId) {
              this.messageId = messageId;
              return this;
          }
  
          public PublishBuilder properties(MqttProperties properties) {
              this.mqttProperties = properties;
              return this;
          }
  
          public MqttPublishMessage build() {
              MqttFixedHeader mqttFixedHeader = new MqttFixedHeader(MqttMessageType.PUBLISH, false, qos, retained, 0);
              MqttPublishVariableHeader mqttVariableHeader =
                      new MqttPublishVariableHeader(topic, messageId, mqttProperties);
              return new MqttPublishMessage(mqttFixedHeader, mqttVariableHeader, Unpooled.buffer().writeBytes(payload));
          }
      }
  
      public static final class ConnectBuilder {
  
          private MqttVersion version = MqttVersion.MQTT_3_1_1;
          private String clientId;
          private boolean cleanSession;
          private boolean hasUser;
          private boolean hasPassword;
          private int keepAliveSecs;
          private MqttProperties willProperties = MqttProperties.NO_PROPERTIES;
          private boolean willFlag;
          private boolean willRetain;
          private MqttQoS willQos = MqttQoS.AT_MOST_ONCE;
          private String willTopic;
          private byte[] willMessage;
          private String username;
          private byte[] password;
          private MqttProperties properties = MqttProperties.NO_PROPERTIES;
  
          ConnectBuilder() {
          }
 
         public ConnectBuilder protocolVersion(MqttVersion version) {
             this.version = version;
             return this;
         }
 
         public ConnectBuilder clientId(String clientId) {
             this.clientId = clientId;
             return this;
         }
 
         public ConnectBuilder cleanSession(boolean cleanSession) {
             this.cleanSession = cleanSession;
             return this;
         }
 
         public ConnectBuilder keepAlive(int keepAliveSecs) {
             this.keepAliveSecs = keepAliveSecs;
             return this;
         }
 
         public ConnectBuilder willFlag(boolean willFlag) {
             this.willFlag = willFlag;
             return this;
         }
 
         public ConnectBuilder willQoS(MqttQoS willQos) {
             this.willQos = willQos;
             return this;
         }
 
         public ConnectBuilder willTopic(String willTopic) {
             this.willTopic = willTopic;
             return this;
         }
 
         /**
          * @deprecated use {@link ConnectBuilder#willMessage(byte[])} instead
          */
         @Deprecated
         public ConnectBuilder willMessage(String willMessage) {
             willMessage(willMessage == null ? null : willMessage.getBytes(CharsetUtil.UTF_8));
             return this;
         }
 
         public ConnectBuilder willMessage(byte[] willMessage) {
             this.willMessage = willMessage;
             return this;
         }
 
         public ConnectBuilder willRetain(boolean willRetain) {
             this.willRetain = willRetain;
             return this;
         }
 
         public ConnectBuilder willProperties(MqttProperties willProperties) {
             this.willProperties = willProperties;
             return this;
         }
 
         public ConnectBuilder hasUser(boolean value) {
             this.hasUser = value;
             return this;
         }
 
         public ConnectBuilder hasPassword(boolean value) {
             this.hasPassword = value;
             return this;
         }
 
         public ConnectBuilder username(String username) {
             this.hasUser = username != null;
             this.username = username;
             return this;
         }
 
         /**
          * @deprecated use {@link ConnectBuilder#password(byte[])} instead
          */
         @Deprecated
         public ConnectBuilder password(String password) {
             password(password == null ? null : password.getBytes(CharsetUtil.UTF_8));
             return this;
         }
 
         public ConnectBuilder password(byte[] password) {
             this.hasPassword = password != null;
             this.password = password;
             return this;
         }
 
         public ConnectBuilder properties(MqttProperties properties) {
             this.properties = properties;
             return this;
         }
 
         public MqttConnectMessage build() {
             MqttFixedHeader mqttFixedHeader =
                     new MqttFixedHeader(MqttMessageType.CONNECT, false, MqttQoS.AT_MOST_ONCE, false, 0);
             MqttConnectVariableHeader mqttConnectVariableHeader =
                     new MqttConnectVariableHeader(
                             version.protocolName(),
                             version.protocolLevel(),
                             hasUser,
                             hasPassword,
                             willRetain,
                             willQos.value(),
                             willFlag,
                             cleanSession,
                             keepAliveSecs,
                             properties);
             MqttConnectPayload mqttConnectPayload =
                     new MqttConnectPayload(clientId, willProperties, willTopic, willMessage, username, password);
             return new MqttConnectMessage(mqttFixedHeader, mqttConnectVariableHeader, mqttConnectPayload);
         }
     }
 
     public static final class SubscribeBuilder {
 
         private List<MqttTopicSubscription> subscriptions;
         private int messageId;
         private MqttProperties properties;
 
         SubscribeBuilder() {
         }
 
         public SubscribeBuilder addSubscription(MqttQoS qos, String topic) {
             ensureSubscriptionsExist();
             subscriptions.add(new MqttTopicSubscription(topic, qos));
             return this;
         }
 
         public SubscribeBuilder addSubscription(String topic, MqttSubscriptionOption option) {
             ensureSubscriptionsExist();
             subscriptions.add(new MqttTopicSubscription(topic, option));
             return this;
         }
 
         public SubscribeBuilder messageId(int messageId) {
             this.messageId = messageId;
             return this;
         }
 
         public SubscribeBuilder properties(MqttProperties properties) {
             this.properties = properties;
             return this;
         }
 
         public MqttSubscribeMessage build() {
             MqttFixedHeader mqttFixedHeader =
                     new MqttFixedHeader(MqttMessageType.SUBSCRIBE, false, MqttQoS.AT_LEAST_ONCE, false, 0);
             MqttMessageIdAndPropertiesVariableHeader mqttVariableHeader =
                     new MqttMessageIdAndPropertiesVariableHeader(messageId, properties);
             MqttSubscribePayload mqttSubscribePayload = new MqttSubscribePayload(subscriptions);
             return new MqttSubscribeMessage(mqttFixedHeader, mqttVariableHeader, mqttSubscribePayload);
         }
 
         private void ensureSubscriptionsExist() {
             if (subscriptions == null) {
                 subscriptions = new ArrayList<MqttTopicSubscription>(5);
             }
         }
     }
 
     public static final class UnsubscribeBuilder {
 
         private List<String> topicFilters;
         private int messageId;
         private MqttProperties properties;
 
         UnsubscribeBuilder() {
         }
 
         public UnsubscribeBuilder addTopicFilter(String topic) {
             if (topicFilters == null) {
                 topicFilters = new ArrayList<String>(5);
             }
             topicFilters.add(topic);
             return this;
         }
 
         public UnsubscribeBuilder messageId(int messageId) {
             this.messageId = messageId;
             return this;
         }
 
         public UnsubscribeBuilder properties(MqttProperties properties) {
             this.properties = properties;
             return this;
         }
 
         public MqttUnsubscribeMessage build() {
             MqttFixedHeader mqttFixedHeader =
                     new MqttFixedHeader(MqttMessageType.UNSUBSCRIBE, false, MqttQoS.AT_LEAST_ONCE, false, 0);
             MqttMessageIdAndPropertiesVariableHeader mqttVariableHeader =
                     new MqttMessageIdAndPropertiesVariableHeader(messageId, properties);
             MqttUnsubscribePayload mqttSubscribePayload = new MqttUnsubscribePayload(topicFilters);
             return new MqttUnsubscribeMessage(mqttFixedHeader, mqttVariableHeader, mqttSubscribePayload);
         }
     }
 
     public interface PropertiesInitializer<T> {
         void apply(T builder);
     }
 
     public static final class ConnAckBuilder {
 
         private MqttConnectReturnCode returnCode;
         private boolean sessionPresent;
         private MqttProperties properties = MqttProperties.NO_PROPERTIES;
         private ConnAckPropertiesBuilder propsBuilder;
 
         private ConnAckBuilder() {
         }
 
         public ConnAckBuilder returnCode(MqttConnectReturnCode returnCode) {
             this.returnCode = returnCode;
             return this;
         }
 
         public ConnAckBuilder sessionPresent(boolean sessionPresent) {
             this.sessionPresent = sessionPresent;
             return this;
         }
 
         public ConnAckBuilder properties(MqttProperties properties) {
             this.properties = properties;
             return this;
         }
 
         public ConnAckBuilder properties(PropertiesInitializer<ConnAckPropertiesBuilder> consumer) {
             if (propsBuilder == null) {
                 propsBuilder = new ConnAckPropertiesBuilder();
             }
             consumer.apply(propsBuilder);
             return this;
         }
 
         public MqttConnAckMessage build() {
             if (propsBuilder != null) {
                 properties = propsBuilder.build();
             }
             MqttFixedHeader mqttFixedHeader =
                     new MqttFixedHeader(MqttMessageType.CONNACK, false, MqttQoS.AT_MOST_ONCE, false, 0);
             MqttConnAckVariableHeader mqttConnAckVariableHeader =
                     new MqttConnAckVariableHeader(returnCode, sessionPresent, properties);
             return new MqttConnAckMessage(mqttFixedHeader, mqttConnAckVariableHeader);
         }
     }
 
     public static final class ConnAckPropertiesBuilder {
         private String clientId;
         private Long sessionExpiryInterval;
         private int receiveMaximum;
         private Byte maximumQos;
         private boolean retain;
         private Long maximumPacketSize;
         private int topicAliasMaximum;
         private String reasonString;
         private final MqttProperties.UserProperties userProperties = new MqttProperties.UserProperties();
         private Boolean wildcardSubscriptionAvailable;
         private Boolean subscriptionIdentifiersAvailable;
         private Boolean sharedSubscriptionAvailable;
         private Integer serverKeepAlive;
         private String responseInformation;
         private String serverReference;
         private String authenticationMethod;
         private byte[] authenticationData;
 
         public MqttProperties build() {
             final MqttProperties props = new MqttProperties();
             if (clientId != null) {
                 props.add(new MqttProperties.StringProperty(MqttPropertyType.ASSIGNED_CLIENT_IDENTIFIER.value(),
                         clientId));
             }
             if (sessionExpiryInterval != null) {
                 props.add(new MqttProperties.IntegerProperty(
                         MqttPropertyType.SESSION_EXPIRY_INTERVAL.value(), sessionExpiryInterval.intValue()));
             }
             if (receiveMaximum > 0) {
                 props.add(new MqttProperties.IntegerProperty(MqttPropertyType.RECEIVE_MAXIMUM.value(), receiveMaximum));
             }
             if (maximumQos != null) {
                 props.add(new MqttProperties.IntegerProperty(MqttPropertyType.MAXIMUM_QOS.value(),
                         maximumQos.intValue()));
             }
             props.add(new MqttProperties.IntegerProperty(MqttPropertyType.RETAIN_AVAILABLE.value(), retain ? 1 : 0));
             if (maximumPacketSize != null) {
                 props.add(new MqttProperties.IntegerProperty(MqttPropertyType.MAXIMUM_PACKET_SIZE.value(),
                         maximumPacketSize.intValue()));
             }
             props.add(new MqttProperties.IntegerProperty(MqttPropertyType.TOPIC_ALIAS_MAXIMUM.value(),
                     topicAliasMaximum));
             if (reasonString != null) {
                 props.add(new MqttProperties.StringProperty(MqttPropertyType.REASON_STRING.value(), reasonString));
             }
             props.add(userProperties);
             if (wildcardSubscriptionAvailable != null) {
                 props.add(new MqttProperties.IntegerProperty(MqttPropertyType.WILDCARD_SUBSCRIPTION_AVAILABLE.value(),
                         wildcardSubscriptionAvailable ? 1 : 0));
             }
             if (subscriptionIdentifiersAvailable != null) {
                 props.add(new MqttProperties.IntegerProperty(MqttPropertyType.SUBSCRIPTION_IDENTIFIER_AVAILABLE.value(),
                         subscriptionIdentifiersAvailable ? 1 : 0));
             }
             if (sharedSubscriptionAvailable != null) {
                 props.add(new MqttProperties.IntegerProperty(MqttPropertyType.SHARED_SUBSCRIPTION_AVAILABLE.value(),
                         sharedSubscriptionAvailable ? 1 : 0));
             }
             if (serverKeepAlive != null) {
                 props.add(new MqttProperties.IntegerProperty(MqttPropertyType.SERVER_KEEP_ALIVE.value(),
                         serverKeepAlive));
             }
             if (responseInformation != null) {
                 props.add(new MqttProperties.StringProperty(MqttPropertyType.RESPONSE_INFORMATION.value(),
                         responseInformation));
             }
             if (serverReference != null) {
                 props.add(new MqttProperties.StringProperty(MqttPropertyType.SERVER_REFERENCE.value(),
                         serverReference));
             }
             if (authenticationMethod != null) {
                 props.add(new MqttProperties.StringProperty(MqttPropertyType.AUTHENTICATION_METHOD.value(),
                         authenticationMethod));
             }
             if (authenticationData != null) {
                 props.add(new MqttProperties.BinaryProperty(MqttPropertyType.AUTHENTICATION_DATA.value(),
                         authenticationData));
             }
 
             return props;
         }
 
         public ConnAckPropertiesBuilder sessionExpiryInterval(long seconds) {
             this.sessionExpiryInterval = seconds;
             return this;
         }
 
         public ConnAckPropertiesBuilder receiveMaximum(int value) {
             this.receiveMaximum = checkPositive(value, "value");
             return this;
         }
 
         public ConnAckPropertiesBuilder maximumQos(byte value) {
             if (value != 0 && value != 1) {
                 throw new IllegalArgumentException("maximum QoS property could be 0 or 1");
             }
             this.maximumQos = value;
             return this;
         }
 
         public ConnAckPropertiesBuilder retainAvailable(boolean retain) {
             this.retain = retain;
             return this;
         }
 
         public ConnAckPropertiesBuilder maximumPacketSize(long size) {
             this.maximumPacketSize = checkPositive(size, "size");
             return this;
         }
 
         public ConnAckPropertiesBuilder assignedClientId(String clientId) {
             this.clientId = clientId;
             return this;
         }
 
         public ConnAckPropertiesBuilder topicAliasMaximum(int value) {
             this.topicAliasMaximum = value;
             return this;
         }
 
         public ConnAckPropertiesBuilder reasonString(String reason) {
             this.reasonString = reason;
             return this;
         }
 
         public ConnAckPropertiesBuilder userProperty(String name, String value) {
             userProperties.add(name, value);
             return this;
         }
 
         public ConnAckPropertiesBuilder wildcardSubscriptionAvailable(boolean value) {
             this.wildcardSubscriptionAvailable = value;
             return this;
         }
 
         public ConnAckPropertiesBuilder subscriptionIdentifiersAvailable(boolean value) {
             this.subscriptionIdentifiersAvailable = value;
             return this;
         }
 
         public ConnAckPropertiesBuilder sharedSubscriptionAvailable(boolean value) {
             this.sharedSubscriptionAvailable = value;
             return this;
         }
 
         public ConnAckPropertiesBuilder serverKeepAlive(int seconds) {
             this.serverKeepAlive = seconds;
             return this;
         }
 
         public ConnAckPropertiesBuilder responseInformation(String value) {
             this.responseInformation = value;
             return this;
         }
 
         public ConnAckPropertiesBuilder serverReference(String host) {
             this.serverReference = host;
             return this;
         }
 
         public ConnAckPropertiesBuilder authenticationMethod(String methodName) {
             this.authenticationMethod = methodName;
             return this;
         }
 
         public ConnAckPropertiesBuilder authenticationData(byte[] rawData) {
             this.authenticationData = rawData.clone();
             return this;
         }
     }
 
     public static final class PubAckBuilder {
 
         private int packetId;
         private byte reasonCode;
         private MqttProperties properties;
 
         PubAckBuilder() {
         }
 
         public PubAckBuilder reasonCode(byte reasonCode) {
             this.reasonCode = reasonCode;
             return this;
         }
 
         public PubAckBuilder packetId(int packetId) {
             this.packetId = packetId;
             return this;
         }
 
         /**
          * @deprecated use {@link PubAckBuilder#packetId(int)} instead
          */
         @Deprecated
         public PubAckBuilder packetId(short packetId) {
             return packetId(packetId & 0xFFFF);
         }
 
         public PubAckBuilder properties(MqttProperties properties) {
             this.properties = properties;
             return this;
         }
 
         public MqttMessage build() {
             MqttFixedHeader mqttFixedHeader =
                     new MqttFixedHeader(MqttMessageType.PUBACK, false, MqttQoS.AT_MOST_ONCE, false, 0);
             MqttPubReplyMessageVariableHeader mqttPubAckVariableHeader =
                     new MqttPubReplyMessageVariableHeader(packetId, reasonCode, properties);
             return new MqttMessage(mqttFixedHeader, mqttPubAckVariableHeader);
         }
     }
 
     public static final class SubAckBuilder {
 
         private int packetId;
         private MqttProperties properties;
         private final List<MqttQoS> grantedQoses = new ArrayList<MqttQoS>();
 
         SubAckBuilder() {
         }
 
         public SubAckBuilder packetId(int packetId) {
             this.packetId = packetId;
             return this;
         }
 
         /**
          * @deprecated use {@link SubAckBuilder#packetId(int)} instead
          */
         @Deprecated
         public SubAckBuilder packetId(short packetId) {
             return packetId(packetId & 0xFFFF);
         }
 
         public SubAckBuilder properties(MqttProperties properties) {
             this.properties = properties;
             return this;
         }
 
         public SubAckBuilder addGrantedQos(MqttQoS qos) {
             this.grantedQoses.add(qos);
             return this;
         }
 
         public SubAckBuilder addGrantedQoses(MqttQoS... qoses) {
             this.grantedQoses.addAll(Arrays.asList(qoses));
             return this;
         }
 
         public MqttSubAckMessage build() {
             MqttFixedHeader mqttFixedHeader =
                     new MqttFixedHeader(MqttMessageType.SUBACK, false, MqttQoS.AT_MOST_ONCE, false, 0);
             MqttMessageIdAndPropertiesVariableHeader mqttSubAckVariableHeader =
                     new MqttMessageIdAndPropertiesVariableHeader(packetId, properties);
 
             //transform to primitive types
             int[] grantedQoses = new int[this.grantedQoses.size()];
             int i = 0;
             for (MqttQoS grantedQos : this.grantedQoses) {
                 grantedQoses[i++] = grantedQos.value();
             }
 
             MqttSubAckPayload subAckPayload = new MqttSubAckPayload(grantedQoses);
             return new MqttSubAckMessage(mqttFixedHeader, mqttSubAckVariableHeader, subAckPayload);
         }
     }
 
     public static final class UnsubAckBuilder {
 
         private int packetId;
         private MqttProperties properties;
         private final List<Short> reasonCodes = new ArrayList<Short>();
 
         UnsubAckBuilder() {
         }
 
         public UnsubAckBuilder packetId(int packetId) {
             this.packetId = packetId;
             return this;
         }
 
         /**
          * @deprecated use {@link UnsubAckBuilder#packetId(int)} instead
          */
         @Deprecated
         public UnsubAckBuilder packetId(short packetId) {
             return packetId(packetId & 0xFFFF);
         }
 
         public UnsubAckBuilder properties(MqttProperties properties) {
             this.properties = properties;
             return this;
         }
 
         public UnsubAckBuilder addReasonCode(short reasonCode) {
             this.reasonCodes.add(reasonCode);
             return this;
         }
 
         public UnsubAckBuilder addReasonCodes(Short... reasonCodes) {
             this.reasonCodes.addAll(Arrays.asList(reasonCodes));
             return this;
         }
 
         public MqttUnsubAckMessage build() {
             MqttFixedHeader mqttFixedHeader =
                     new MqttFixedHeader(MqttMessageType.UNSUBACK, false, MqttQoS.AT_MOST_ONCE, false, 0);
             MqttMessageIdAndPropertiesVariableHeader mqttSubAckVariableHeader =
                     new MqttMessageIdAndPropertiesVariableHeader(packetId, properties);
 
             MqttUnsubAckPayload subAckPayload = new MqttUnsubAckPayload(reasonCodes);
             return new MqttUnsubAckMessage(mqttFixedHeader, mqttSubAckVariableHeader, subAckPayload);
         }
     }
 
     public static final class DisconnectBuilder {
 
         private MqttProperties properties;
         private byte reasonCode;
 
         DisconnectBuilder() {
         }
 
         public DisconnectBuilder properties(MqttProperties properties) {
             this.properties = properties;
             return this;
         }
 
         public DisconnectBuilder reasonCode(byte reasonCode) {
             this.reasonCode = reasonCode;
             return this;
         }
 
         public MqttMessage build() {
             MqttFixedHeader mqttFixedHeader =
                     new MqttFixedHeader(MqttMessageType.DISCONNECT, false, MqttQoS.AT_MOST_ONCE, false, 0);
             MqttReasonCodeAndPropertiesVariableHeader mqttDisconnectVariableHeader =
                     new MqttReasonCodeAndPropertiesVariableHeader(reasonCode, properties);
 
             return new MqttMessage(mqttFixedHeader, mqttDisconnectVariableHeader);
         }
     }
 
     public static final class AuthBuilder {
 
         private MqttProperties properties;
         private byte reasonCode;
 
         AuthBuilder() {
         }
 
         public AuthBuilder properties(MqttProperties properties) {
             this.properties = properties;
             return this;
         }
 
         public AuthBuilder reasonCode(byte reasonCode) {
             this.reasonCode = reasonCode;
             return this;
         }
 
         public MqttMessage build() {
             MqttFixedHeader mqttFixedHeader =
                     new MqttFixedHeader(MqttMessageType.AUTH, false, MqttQoS.AT_MOST_ONCE, false, 0);
             MqttReasonCodeAndPropertiesVariableHeader mqttAuthVariableHeader =
                     new MqttReasonCodeAndPropertiesVariableHeader(reasonCode, properties);
 
             return new MqttMessage(mqttFixedHeader, mqttAuthVariableHeader);
         }
     }
 
     public static ConnectBuilder connect() {
         return new ConnectBuilder();
     }
 
     public static ConnAckBuilder connAck() {
         return new ConnAckBuilder();
     }
 
     public static PublishBuilder publish() {
         return new PublishBuilder();
     }
 
     public static SubscribeBuilder subscribe() {
         return new SubscribeBuilder();
     }
 
     public static UnsubscribeBuilder unsubscribe() {
         return new UnsubscribeBuilder();
     }
 
     public static PubAckBuilder pubAck() {
         return new PubAckBuilder();
     }
 
     public static SubAckBuilder subAck() {
         return new SubAckBuilder();
     }
 
     public static UnsubAckBuilder unsubAck() {
         return new UnsubAckBuilder();
     }
 
     public static DisconnectBuilder disconnect() {
         return new DisconnectBuilder();
     }
 
     public static AuthBuilder auth() {
         return new AuthBuilder();
     }
 
     private MqttMessageBuilders() {
     }
 }