/*
 * 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.queryengine.plan.planner.plan.node.process;

import org.apache.iotdb.db.queryengine.plan.planner.plan.node.PlanNode;
import org.apache.iotdb.db.queryengine.plan.planner.plan.node.PlanNodeId;
import org.apache.iotdb.db.queryengine.plan.planner.plan.node.PlanNodeType;
import org.apache.iotdb.db.queryengine.plan.planner.plan.node.PlanVisitor;
import org.apache.iotdb.tsfile.utils.ReadWriteIOUtils;

import java.io.DataOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;

public class SingleDeviceViewNode extends SingleChildProcessNode {

  private final String device;

  // To reduce memory cost, SingleDeviceViewNode doesn't serialize and deserialize
  // outputColumnNames.It just rebuilds using the infos from parent node.
  private final List<String> outputColumnNames;
  private final List<Integer> deviceToMeasurementIndexes;
  // For some isolated SingleDeviceViewNodes without parent node, they need to cache
  // the outputColumnNames themselves.
  private boolean cacheOutputColumnNames = false;

  public SingleDeviceViewNode(
      PlanNodeId id,
      List<String> outputColumnNames,
      String device,
      List<Integer> deviceToMeasurementIndexes) {
    super(id);
    this.device = device;
    this.outputColumnNames = outputColumnNames;
    this.deviceToMeasurementIndexes = deviceToMeasurementIndexes;
  }

  public SingleDeviceViewNode(
      PlanNodeId id,
      boolean cacheOutputColumnNames,
      List<String> outputColumnNames,
      String device,
      List<Integer> deviceToMeasurementIndexes) {
    super(id);
    this.device = device;
    this.cacheOutputColumnNames = cacheOutputColumnNames;
    this.outputColumnNames = outputColumnNames;
    this.deviceToMeasurementIndexes = deviceToMeasurementIndexes;
  }

  @Override
  public PlanNode clone() {
    return new SingleDeviceViewNode(
        getPlanNodeId(),
        cacheOutputColumnNames,
        outputColumnNames,
        device,
        deviceToMeasurementIndexes);
  }

  @Override
  public List<String> getOutputColumnNames() {
    return this.outputColumnNames;
  }

  public void setCacheOutputColumnNames(boolean cacheOutputColumnNames) {
    this.cacheOutputColumnNames = cacheOutputColumnNames;
  }

  public String getDevice() {
    return device;
  }

  public boolean isCacheOutputColumnNames() {
    return cacheOutputColumnNames;
  }

  public List<Integer> getDeviceToMeasurementIndexes() {
    return deviceToMeasurementIndexes;
  }

  @Override
  public <R, C> R accept(PlanVisitor<R, C> visitor, C context) {
    return visitor.visitSingleDeviceView(this, context);
  }

  @Override
  protected void serializeAttributes(ByteBuffer byteBuffer) {
    PlanNodeType.SINGLE_DEVICE_VIEW.serialize(byteBuffer);
    ReadWriteIOUtils.write(device, byteBuffer);
    ReadWriteIOUtils.write(cacheOutputColumnNames, byteBuffer);
    ReadWriteIOUtils.write(deviceToMeasurementIndexes.size(), byteBuffer);
    for (Integer index : deviceToMeasurementIndexes) {
      ReadWriteIOUtils.write(index, byteBuffer);
    }
    if (cacheOutputColumnNames) {
      ReadWriteIOUtils.write(outputColumnNames.size(), byteBuffer);
      for (String column : outputColumnNames) {
        ReadWriteIOUtils.write(column, byteBuffer);
      }
    }
  }

  @Override
  protected void serializeAttributes(DataOutputStream stream) throws IOException {
    PlanNodeType.SINGLE_DEVICE_VIEW.serialize(stream);
    ReadWriteIOUtils.write(device, stream);
    ReadWriteIOUtils.write(cacheOutputColumnNames, stream);
    ReadWriteIOUtils.write(deviceToMeasurementIndexes.size(), stream);
    for (Integer index : deviceToMeasurementIndexes) {
      ReadWriteIOUtils.write(index, stream);
    }
    if (cacheOutputColumnNames) {
      ReadWriteIOUtils.write(outputColumnNames.size(), stream);
      for (String column : outputColumnNames) {
        ReadWriteIOUtils.write(column, stream);
      }
    }
  }

  public static SingleDeviceViewNode deserialize(ByteBuffer byteBuffer) {
    String device = ReadWriteIOUtils.readString(byteBuffer);
    boolean cacheOutputColumnNames = ReadWriteIOUtils.readBool(byteBuffer);
    int listSize = ReadWriteIOUtils.readInt(byteBuffer);
    List<Integer> deviceToMeasurementIndexes = new ArrayList<>(listSize);
    while (listSize > 0) {
      deviceToMeasurementIndexes.add(ReadWriteIOUtils.readInt(byteBuffer));
      listSize--;
    }
    List<String> outputColumnNames = null;
    if (cacheOutputColumnNames) {
      int columnSize = ReadWriteIOUtils.readInt(byteBuffer);
      outputColumnNames = new ArrayList<>();
      while (columnSize > 0) {
        outputColumnNames.add(ReadWriteIOUtils.readString(byteBuffer));
        columnSize--;
      }
    }

    PlanNodeId planNodeId = PlanNodeId.deserialize(byteBuffer);
    return new SingleDeviceViewNode(
        planNodeId, cacheOutputColumnNames, outputColumnNames, device, deviceToMeasurementIndexes);
  }

  @Override
  public boolean equals(Object o) {
    if (this == o) {
      return true;
    }
    if (o == null || o.getClass() != getClass()) {
      return false;
    }
    if (!super.equals(o)) {
      return false;
    }
    SingleDeviceViewNode that = (SingleDeviceViewNode) o;
    return device.equals(that.device)
        && outputColumnNames.equals(that.outputColumnNames)
        && deviceToMeasurementIndexes.equals(that.deviceToMeasurementIndexes);
  }

  @Override
  public int hashCode() {
    return Objects.hash(super.hashCode(), device, outputColumnNames, deviceToMeasurementIndexes);
  }

  @Override
  public String toString() {
    return "SingleDeviceView-" + this.getPlanNodeId();
  }
}
