/**
 * 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_REGEXP_INSTR_
#define OCEANBASE_SQL_ENGINE_EXPR_OB_EXPR_REGEXP_INSTR_

#include "lib/string/ob_string.h"
#include "sql/engine/expr/ob_expr_regexp_context.h"

namespace oceanbase
{
namespace sql
{
class ObExprRegexpInstr : public ObFuncExprOperator
{
public:
  explicit ObExprRegexpInstr(common::ObIAllocator &alloc);
  virtual ~ObExprRegexpInstr();
  virtual int calc_result_typeN(ObExprResType &type,
                                ObExprResType *types,
                                int64_t param_num,
                                common::ObExprTypeCtx &type_ctx) const;
  virtual int cg_expr(ObExprCGCtx &op_cg_ctx,
                      const ObRawExpr &raw_expr,
                      ObExpr &rt_expr) const override;
  virtual bool need_rt_ctx() const override { return true; }

  static int eval_regexp_instr(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &expr_datum);
private:
  static int calc(int64_t &ret_pos, const common::ObString &text,
                  const common::ObString &pattern, int64_t position,
                  int64_t occurrence, int64_t return_option,
                  const common::ObCollationType cs_type, const common::ObString &match_param,
                  int64_t subexpr, bool has_null_argument, bool reusable,
                  ObExprRegexContext *regexp_ptr, common::ObExprStringBuf &string_buf,
                  common::ObIAllocator &exec_ctx_alloc);
private:
  DISALLOW_COPY_AND_ASSIGN(ObExprRegexpInstr);
};
}
}
#endif /* OCEANBASE_SQL_ENGINE_EXPR_OB_EXPR_REGEXP_SUBSTR_ */