/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF 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 org.apache.iotdb.db.protocol.mqtt;

import org.apache.iotdb.common.rpc.thrift.TSStatus;
import org.apache.iotdb.commons.conf.IoTDBConstant.ClientVersion;
import org.apache.iotdb.db.auth.AuthorityChecker;
import org.apache.iotdb.db.conf.IoTDBConfig;
import org.apache.iotdb.db.conf.IoTDBDescriptor;
import org.apache.iotdb.db.protocol.session.MqttClientSession;
import org.apache.iotdb.db.protocol.session.SessionManager;
import org.apache.iotdb.db.queryengine.plan.Coordinator;
import org.apache.iotdb.db.queryengine.plan.analyze.ClusterPartitionFetcher;
import org.apache.iotdb.db.queryengine.plan.analyze.IPartitionFetcher;
import org.apache.iotdb.db.queryengine.plan.analyze.cache.schema.DataNodeDevicePathCache;
import org.apache.iotdb.db.queryengine.plan.analyze.schema.ClusterSchemaFetcher;
import org.apache.iotdb.db.queryengine.plan.analyze.schema.ISchemaFetcher;
import org.apache.iotdb.db.queryengine.plan.execution.ExecutionResult;
import org.apache.iotdb.db.queryengine.plan.statement.crud.InsertRowStatement;
import org.apache.iotdb.db.utils.CommonUtils;
import org.apache.iotdb.db.utils.TimestampPrecisionUtils;
import org.apache.iotdb.rpc.TSStatusCode;
import org.apache.iotdb.service.rpc.thrift.TSProtocolVersion;

import io.moquette.interception.AbstractInterceptHandler;
import io.moquette.interception.messages.InterceptConnectMessage;
import io.moquette.interception.messages.InterceptDisconnectMessage;
import io.moquette.interception.messages.InterceptPublishMessage;
import io.netty.buffer.ByteBuf;
import io.netty.handler.codec.mqtt.MqttQoS;
import org.apache.tsfile.enums.TSDataType;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.time.ZoneId;
import java.util.List;
import java.util.concurrent.ConcurrentHashMap;

/** PublishHandler handle the messages from MQTT clients. */
public class MPPPublishHandler extends AbstractInterceptHandler {

  private static final Logger LOG = LoggerFactory.getLogger(MPPPublishHandler.class);

  private static final IoTDBConfig config = IoTDBDescriptor.getInstance().getConfig();
  private final SessionManager sessionManager = SessionManager.getInstance();

  private final ConcurrentHashMap<String, MqttClientSession> clientIdToSessionMap =
      new ConcurrentHashMap<>();
  private final PayloadFormatter payloadFormat;
  private final IPartitionFetcher partitionFetcher;
  private final ISchemaFetcher schemaFetcher;

  public MPPPublishHandler(IoTDBConfig config) {
    this.payloadFormat = PayloadFormatManager.getPayloadFormat(config.getMqttPayloadFormatter());
    partitionFetcher = ClusterPartitionFetcher.getInstance();
    schemaFetcher = ClusterSchemaFetcher.getInstance();
  }

  @Override
  public String getID() {
    return "iotdb-mqtt-broker-listener";
  }

  @Override
  public void onConnect(InterceptConnectMessage msg) {
    if (msg.getClientID() == null || msg.getClientID().trim().isEmpty()) {
      LOG.error(
          "Connection refused: client_id is missing or empty. A valid client_id is required to establish a connection.");
    }
    if (!clientIdToSessionMap.containsKey(msg.getClientID())) {
      MqttClientSession session = new MqttClientSession(msg.getClientID());
      sessionManager.login(
          session,
          msg.getUsername(),
          new String(msg.getPassword()),
          ZoneId.systemDefault().toString(),
          TSProtocolVersion.IOTDB_SERVICE_PROTOCOL_V3,
          ClientVersion.V_1_0);
      sessionManager.registerSessionForMqtt(session);
      clientIdToSessionMap.put(msg.getClientID(), session);
    }
  }

  @Override
  public void onDisconnect(InterceptDisconnectMessage msg) {
    MqttClientSession session = clientIdToSessionMap.remove(msg.getClientID());
    if (null != session) {
      sessionManager.removeCurrSessionForMqtt(session);
      sessionManager.closeSession(session, Coordinator.getInstance()::cleanupQueryExecution);
    }
  }

  @Override
  public void onPublish(InterceptPublishMessage msg) {
    try {
      String clientId = msg.getClientID();
      if (!clientIdToSessionMap.containsKey(clientId)) {
        return;
      }
      MqttClientSession session = clientIdToSessionMap.get(msg.getClientID());
      ByteBuf payload = msg.getPayload();
      String topic = msg.getTopicName();
      String username = msg.getUsername();
      MqttQoS qos = msg.getQos();

      LOG.debug(
          "Receive publish message. clientId: {}, username: {}, qos: {}, topic: {}, payload: {}",
          clientId,
          username,
          qos,
          topic,
          payload);

      List<Message> events = payloadFormat.format(topic, payload);
      if (events == null) {
        return;
      }

      for (Message event : events) {
        if (event == null) {
          continue;
        }

        TSStatus tsStatus = null;
        try {
          InsertRowStatement statement = new InsertRowStatement();
          statement.setDevicePath(
              DataNodeDevicePathCache.getInstance().getPartialPath(event.getDevice()));
          TimestampPrecisionUtils.checkTimestampPrecision(event.getTimestamp());
          statement.setTime(event.getTimestamp());
          statement.setMeasurements(event.getMeasurements().toArray(new String[0]));
          if (event.getDataTypes() == null) {
            statement.setDataTypes(new TSDataType[event.getMeasurements().size()]);
            statement.setValues(event.getValues().toArray(new Object[0]));
            statement.setNeedInferType(true);
          } else {
            List<TSDataType> dataTypes = event.getDataTypes();
            List<String> values = event.getValues();
            Object[] inferredValues = new Object[values.size()];
            for (int i = 0; i < values.size(); ++i) {
              inferredValues[i] = CommonUtils.parseValue(dataTypes.get(i), values.get(i));
            }
            statement.setDataTypes(dataTypes.toArray(new TSDataType[0]));
            statement.setValues(inferredValues);
          }
          statement.setAligned(false);

          tsStatus = AuthorityChecker.checkAuthority(statement, session);
          if (tsStatus.getCode() != TSStatusCode.SUCCESS_STATUS.getStatusCode()) {
            LOG.warn(tsStatus.message);
          } else {
            long queryId = sessionManager.requestQueryId();
            ExecutionResult result =
                Coordinator.getInstance()
                    .executeForTreeModel(
                        statement,
                        queryId,
                        sessionManager.getSessionInfo(session),
                        "",
                        partitionFetcher,
                        schemaFetcher,
                        config.getQueryTimeoutThreshold(),
                        false);
            tsStatus = result.status;
          }
        } catch (Exception e) {
          LOG.warn(
              "meet error when inserting device {}, measurements {}, at time {}, because ",
              event.getDevice(),
              event.getMeasurements(),
              event.getTimestamp(),
              e);
        }
        LOG.debug("event process result: {}", tsStatus);
      }
    } finally {
      // release the payload of the message
      super.onPublish(msg);
    }
  }

  @Override
  public void onSessionLoopError(Throwable throwable) {
    // TODO: Implement something sensible here ...
  }
}
