content: /*
   * Copyright (C) 2016-2023 ActionTech.
   * License: http://www.gnu.org/licenses/gpl.html GPL version 2 or higher.
   */
  
  package com.actiontech.dble.services.manager.response;
  
  import com.actiontech.dble.backend.mysql.CharsetUtil;
  import com.actiontech.dble.backend.mysql.CollationInfo;
  import com.actiontech.dble.backend.mysql.PacketUtil;
  import com.actiontech.dble.config.Fields;
  import com.actiontech.dble.net.mysql.*;
  import com.actiontech.dble.services.manager.ManagerService;
  import com.actiontech.dble.util.LongUtil;
  import com.actiontech.dble.util.StringUtil;
  
  import java.nio.ByteBuffer;
  
  /**
   * Created by szf on 2018/12/7.
   */
  public final class ShowCollatin {
      private ShowCollatin() {
      }
  
      private static final int FIELD_COUNT = 6;
      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();
  
      static {
          int i = 0;
          byte packetId = 0;
          HEADER.setPacketId(++packetId);
  
          FIELDS[i] = PacketUtil.getField("Collation", Fields.FIELD_TYPE_VAR_STRING);
          FIELDS[i++].setPacketId(++packetId);
          FIELDS[i] = PacketUtil.getField("Charset", Fields.FIELD_TYPE_VAR_STRING);
          FIELDS[i++].setPacketId(++packetId);
          FIELDS[i] = PacketUtil.getField("Id", Fields.FIELD_TYPE_LONG);
          FIELDS[i++].setPacketId(++packetId);
          FIELDS[i] = PacketUtil.getField("Default", Fields.FIELD_TYPE_VAR_STRING);
          FIELDS[i++].setPacketId(++packetId);
          FIELDS[i] = PacketUtil.getField("Compiled", Fields.FIELD_TYPE_VAR_STRING);
          FIELDS[i++].setPacketId(++packetId);
          FIELDS[i] = PacketUtil.getField("Sortlen", Fields.FIELD_TYPE_LONG);
          FIELDS[i++].setPacketId(++packetId);
          EOF.setPacketId(++packetId);
      }
  
      public static void execute(ManagerService service) {
  
          ByteBuffer buffer = service.allocate();
  
          // write header
          buffer = HEADER.write(buffer, service, true);
  
          // write fields
          for (FieldPacket field : FIELDS) {
              buffer = field.write(buffer, service, true);
          }
  
          // write eof
          buffer = EOF.write(buffer, service, true);
  
          // write rows
          byte packetId = EOF.getPacketId();
  
          CollationInfo[] list = CharsetUtil.getAllCollationInfo();
          for (int i = 1; i < list.length; i++) {
              if (list[i] != null) {
                  RowDataPacket row = getRow(list[i], service.getCharset().getResults());
                  row.setPacketId(++packetId);
                  buffer = row.write(buffer, service, true);
              }
          }
  
          // write last eof
          EOFRowPacket lastEof = new EOFRowPacket();
          lastEof.setPacketId(++packetId);
  
  
          lastEof.write(buffer, service);
  
      }
  
  
      private static RowDataPacket getRow(CollationInfo collationInfo, String charset) {
          RowDataPacket row = new RowDataPacket(FIELD_COUNT);
          row.add(StringUtil.encode(collationInfo.getCollation(), charset));
          row.add(StringUtil.encode(collationInfo.getCharset(), charset));
          row.add(LongUtil.toBytes(collationInfo.getId()));
          row.add(StringUtil.encode(collationInfo.isDefault() ? "Yes" : "", charset));
          row.add(StringUtil.encode("Yes", charset));
          row.add(LongUtil.toBytes(1));
          return row;
      }
  }
  