/* Copyright (c) 2018, 2021, Alibaba and/or its affiliates. All rights reserved.
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.
   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL/PolarDB-X Engine hereby grant you an
   additional permission to link the program and your derivative works with the
   separately licensed software that they have included with
   MySQL/PolarDB-X Engine.
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License, version 2.0, for more details.
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */


#include "sql/package/proc.h"

class sys_var;
class THD;

namespace im {
extern LEX_CSTRING ADMIN_PROC_SCHEMA;

class Sql_cmd_show_native_procedure : public Sql_cmd_admin_proc {
 public:
  explicit Sql_cmd_show_native_procedure(THD *thd, List<Item> *list,
                                         const Proc *proc)
      : Sql_cmd_admin_proc(thd, list, proc) {}
  /**
    Implementation of Proc execution body.

    @param[in]    THD           Thread context

    @retval       true          Failure
    @retval       false         Success
  */
  virtual bool pc_execute(THD *thd);

  /* Override default send_result */
  virtual void send_result(THD *thd, bool error);
};

class Show_native_procedure_proc : public Proc, public Disable_copy_base {
  using Sql_cmd_type = Sql_cmd_show_native_procedure;

  enum enum_column {
    COLUMN_SCHEMA_NAME = 0,
    COLUMN_ELEMENT_NAME,
    PROC_TYPE,
    PARAMETERS,
    COLUMN_LAST
  };

 public:
  explicit Show_native_procedure_proc(PSI_memory_key key = 0) : Proc(key) {
    m_result_type = Result_type::RESULT_SET;
    Column_element elements[COLUMN_LAST] = {
        {MYSQL_TYPE_VARCHAR, C_STRING_WITH_LEN("SCHEMA_NAME"), 128},
        {MYSQL_TYPE_VARCHAR, C_STRING_WITH_LEN("PROC_NAME"), 128},
        {MYSQL_TYPE_VARCHAR, C_STRING_WITH_LEN("PROC_TYPE"), 128},
        {MYSQL_TYPE_VARCHAR, C_STRING_WITH_LEN("PARAMETERS"), 1024}};
    for (size_t i = 0; i < COLUMN_LAST; i++) {
      m_columns.assign_at(i, elements[i]);
    }
  }
  
  /* Singleton instance */
  static Proc *instance();

  /**
    Evoke the sql_cmd object for proc.
  */
  virtual Sql_cmd *evoke_cmd(THD *thd, List<Item> *list) const;

  virtual ~Show_native_procedure_proc() {}

  /* Proc name */
  virtual const std::string str() const {
    return std::string("show_native_procedure");
  }

  virtual const std::string qname() const {
    std::stringstream ss;
    ss << im::ADMIN_PROC_SCHEMA.str << "." << str();
    return ss.str();
  }
};

} /* namespace im */