/**
 * Copyright (c) 2021 OceanBase
 * OceanBase CE 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 OCEANBASE_SQL_ENGINE_EXPR_OB_EXPR_WEGHT_STRING_H_
#define OCEANBASE_SQL_ENGINE_EXPR_OB_EXPR_WEGHT_STRING_H_
#include "sql/engine/expr/ob_expr_operator.h"
#include "share/object/ob_obj_cast.h"

namespace oceanbase
{
namespace sql
{
class ObExprWeightString : public ObStringExprOperator
{
public:
  explicit ObExprWeightString(common::ObIAllocator &alloc);
  virtual ~ObExprWeightString() override;
  virtual int calc_resultN(common::ObObj &result,
                           const common::ObObj *objs,
                           int64_t param_num,
                           common::ObExprCtx &expr_ctx) const override;
  virtual int calc_result_typeN(ObExprResType &type,
                                ObExprResType *types,
                                int64_t param_num,
                                common::ObExprTypeCtx &type_ctx) const override;
  static int eval_weight_string(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &epr_datum);
  virtual int cg_expr(ObExprCGCtx &op_cg_ctx, const ObRawExpr &raw_expr, ObExpr &rt_expr) const override;

private:
  static uint64_t ob_strxfrm_flag_normalize(uint64_t flags, uint64_t maximum);
  DISALLOW_COPY_AND_ASSIGN(ObExprWeightString);
};
}
}
#endif /* OCEANBASE_SQL_ENGINE_EXPR_OB_EXPR_WEGHT_STRING_H_ */