content: /*
   * Copyright (C) 2016-2023 ActionTech.
   * 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.net.mysql.*;
  import com.actiontech.dble.services.mysqlsharding.ShardingService;
  import com.actiontech.dble.util.StringUtil;
  
  import java.nio.ByteBuffer;
  import java.util.List;
  
  public final class ShowTrace {
      private ShowTrace() {
      }
  
      private static final int FIELD_COUNT = 6;
      private static final FieldPacket[] FIELDS = new FieldPacket[FIELD_COUNT];
  
      static {
          FIELDS[0] = PacketUtil.getField("OPERATION", Fields.FIELD_TYPE_VAR_STRING);
          FIELDS[1] = PacketUtil.getField("START(ms)", Fields.FIELD_TYPE_VAR_STRING);
          FIELDS[2] = PacketUtil.getField("END(ms)", Fields.FIELD_TYPE_VAR_STRING);
          FIELDS[3] = PacketUtil.getField("DURATION(ms)", Fields.FIELD_TYPE_VAR_STRING);
          FIELDS[4] = PacketUtil.getField("SHARDING_NODE", Fields.FIELD_TYPE_VAR_STRING);
          FIELDS[5] = PacketUtil.getField("SQL/REF", Fields.FIELD_TYPE_VAR_STRING);
      }
  
      public static void response(ShardingService shardingService) {
          ByteBuffer buffer = shardingService.allocate();
  
          // writeDirectly header
          ResultSetHeaderPacket header = PacketUtil.getHeader(FIELD_COUNT);
          byte packetId = header.getPacketId();
          buffer = header.write(buffer, shardingService, true);
  
          // writeDirectly fields
          for (FieldPacket field : FIELDS) {
              field.setPacketId(++packetId);
              buffer = field.write(buffer, shardingService, true);
          }
  
          // writeDirectly eof
          EOFPacket eof = new EOFPacket();
          eof.setPacketId(++packetId);
          buffer = eof.write(buffer, shardingService, true);
  
          List<String[]> results = shardingService.getSession2().genTraceResult();
          if (results != null) {
              for (String[] result : results) {
                  RowDataPacket row = new RowDataPacket(FIELD_COUNT);
                  for (int i = 0; i < FIELD_COUNT; i++) {
                      row.add(StringUtil.encode(result[i], shardingService.getCharset().getResults()));
                  }
                  row.setPacketId(++packetId);
                  buffer = row.write(buffer, shardingService, true);
              }
          }
          // writeDirectly last eof
          EOFRowPacket lastEof = new EOFRowPacket();
          lastEof.setPacketId(++packetId);
          lastEof.write(buffer, shardingService);
      }
  }
  