/**
 * Copyright (c) 2021 OceanBase
 * OceanBase Database Proxy(ODP) is licensed under Mulan PubL v2.
 * You can use this software according to the terms and conditions of the Mulan PubL v2.
 * You may obtain a copy of Mulan PubL v2 at:
 *          http://license.coscl.org.cn/MulanPubL-2.0
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
 * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
 * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 * See the Mulan PubL v2 for more details.
 */

#ifndef OBPROXY_MYSQL_ANALYZER_UTILS_H
#define OBPROXY_MYSQL_ANALYZER_UTILS_H

#include "lib/ob_define.h"
#include "proxy/mysqllib/ob_mysql_common_define.h"

namespace oceanbase
{
namespace obproxy
{
class ObZlibStreamCompressor;
namespace event
{
class ObIOBufferReader;
class ObMIOBuffer;
}
namespace proxy
{
class ObMysqlCompressedAnalyzeResult;

class ObMysqlAnalyzerUtils
{
public:
  // judge whether one mysql compressed packet has been received complete, and get packt len
  // if completed, return ANALYZE_DONE
  // if not,       return ANALYZE_CONT
  static int analyze_one_compressed_packet(event::ObIOBufferReader &reader,
                                           ObMysqlCompressedAnalyzeResult &result);

  static int analyze_compressed_packet_header(const char *start, const int64_t len,
                                              ObMysqlCompressedPacketHeader &header);

  // @reader, contain the standard mysql data;
  // @data_len, the len of standard mysql data to be compressed
  // @write_buf, the compressed data will be written to
  // if succ, reader will consume data_len
  static int consume_and_normal_compress_data(event::ObIOBufferReader *reader,
                                              event::ObMIOBuffer *write_buf,
                                              const int64_t data_len,
                                              uint8_t &compressed_seq,
                                              const bool is_checksum_on);

  // @reader, contain the standard mysql data;
  // @data_len, the len of standard mysql data to be compressed
  // @write_buf, the compressed data will be written to
  // if succ, reader will consume data_len
  static int consume_and_fast_compress_data(event::ObIOBufferReader *reader,
                                            event::ObMIOBuffer *write_buf,
                                            const int64_t data_len,
                                            uint8_t &compressed_seq);

  static int consume_and_compress_data(event::ObIOBufferReader *reader,
                                       event::ObMIOBuffer *write_buf,
                                       const int64_t data_len,
                                       const bool use_fast_compress,
                                       uint8_t &compressed_seq,
                                       const bool is_checksum_on);

  static int stream_compress_data(ObZlibStreamCompressor &compressor,
                                  event::ObMIOBuffer *write_buf, const char *buf,
                                  const int64_t len, const bool is_last_data,
                                  int64_t &compressed_len);

  static int stream_compress_data(event::ObMIOBuffer *write_buf, const char *buf,
                                  const int64_t len, int64_t &compressed_len);


  static int reserve_compressed_hdr(event::ObMIOBuffer *write_buf, char *&hdr_start);

  static int fill_compressed_header(const int64_t uncompress_len, const uint8_t seq,
                                    const int64_t compressed_len,
                                    char *compressed_hdr_buf_start);

};

} // end of namespace proxy
} // end of namespace obproxy
} // end of namespace oceanbase
#endif /* OBPROXY_MYSQL_ANALYZER_UTILS_H */