content: /*
   * Copyright (C) 2016-2023 ActionTech.
   * based on code by MyCATCopyrightHolder Copyright (c) 2013, OpenCloudDB/MyCAT.
   * License: http://www.gnu.org/licenses/gpl.html GPL version 2 or higher.
   */
  package com.actiontech.dble.server.response;
  
  import com.actiontech.dble.backend.mysql.PacketUtil;
  import com.actiontech.dble.config.Fields;
  import com.actiontech.dble.config.Versions;
  import com.actiontech.dble.net.mysql.*;
  import com.actiontech.dble.services.mysqlsharding.ShardingService;
  
  import java.nio.ByteBuffer;
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * @author mycat
   */
  public final class SelectVersion implements InnerFuncResponse {
  
      private static final int FIELD_COUNT = 1;
      private static final ResultSetHeaderPacket HEADER = PacketUtil.getHeader(FIELD_COUNT);
      private static final FieldPacket[] FIELDS = new FieldPacket[FIELD_COUNT];
      private static final EOFPacket EOF = new EOFPacket();
  
  
      public static void response(ShardingService service) {
          HEADER.setPacketId(service.nextPacketId());
          FIELDS[0] = PacketUtil.getField("VERSION()", Fields.FIELD_TYPE_VAR_STRING);
          FIELDS[0].setPacketId(service.nextPacketId());
          EOF.setPacketId(service.nextPacketId());
  
  
          ByteBuffer buffer = service.allocate();
          buffer = HEADER.write(buffer, service, true);
          for (FieldPacket field : FIELDS) {
              buffer = field.write(buffer, service, true);
          }
          buffer = EOF.write(buffer, service, true);
  
          RowDataPacket row = new RowDataPacket(FIELD_COUNT);
          row.add(Versions.getServerVersion());
          row.setPacketId(service.nextPacketId());
          buffer = row.write(buffer, service, true);
          EOFRowPacket lastEof = new EOFRowPacket();
          lastEof.setPacketId(service.nextPacketId());
          lastEof.write(buffer, service);
      }
  
  
      public List<FieldPacket> getField() {
          List<FieldPacket> result = new ArrayList<>();
          result.add(PacketUtil.getField("VERSION()", Fields.FIELD_TYPE_VAR_STRING));
          return result;
      }
  
      public List<RowDataPacket> getRows(ShardingService service) {
          List<RowDataPacket> result = new ArrayList<>();
          RowDataPacket row = new RowDataPacket(FIELD_COUNT);
          row.add(Versions.getServerVersion());
          result.add(row);
          return result;
      }
  
  }
  