/*
 * Copyright (c) 2015, 2023, Oracle and/or its affiliates.
 *
 * 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 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.
 *
 * 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
 */

#ifndef _XPL_EXPR_GENERATOR_H_
#define _XPL_EXPR_GENERATOR_H_

#include "query_string_builder.h"
#include "ngs_common/protocol_protobuf.h"
#include <stdexcept>


namespace xpl
{

class Expression_generator
{
public:
  typedef ::Mysqlx::Expr::Expr Expr;
  typedef ::google::protobuf::RepeatedPtrField< ::Mysqlx::Datatypes::Scalar > Args;

  class Error : public std::invalid_argument
  {
    int m_error;
  public:
    Error(int error_code, const std::string& message);

    int error() const { return m_error; }
  };

  // source: ``Mysqlx.Resultset.ColumnMetadata`` for list of known values
  enum Octets_content_type
  {
    CT_PLAIN = 0x0000,       //   default value; general use of octets
    CT_GEOMETRY = 0x0001,    //   BYTES  0x0001 GEOMETRY (WKB encoding)
    CT_JSON = 0x0002,        //   BYTES  0x0002 JSON (text encoding)
    CT_XML = 0x0003          //   BYTES  0x0003 XML (text encoding)
  };

  Expression_generator(Query_string_builder &qb, const Args &args, const std::string &default_schema, const bool &is_relational)
  : m_qb(qb), m_args(args), m_default_schema(default_schema), m_is_relational(is_relational)
  {}

  template<typename T>
  inline void feed(const T &expr) const { generate(expr); }

  Expression_generator clone(Query_string_builder &qb) const;
  Query_string_builder &query_string_builder() const { return m_qb; }

private:
  typedef ::google::protobuf::RepeatedPtrField< ::Mysqlx::Expr::DocumentPathItem > Document_path;
  typedef ::google::protobuf::uint32 Placeholder;

  void generate(const Mysqlx::Expr::Expr &arg) const;
  void generate(const Mysqlx::Expr::Identifier &arg, const bool is_function=false) const;
  void generate(const Mysqlx::Expr::ColumnIdentifier &arg) const;
  void generate(const Mysqlx::Expr::FunctionCall &arg) const;
  void generate(const Mysqlx::Expr::Operator &arg) const;
  void generate(const Mysqlx::Datatypes::Any &arg) const;
  void generate(const Mysqlx::Datatypes::Scalar &arg) const;
  void generate(const Mysqlx::Datatypes::Scalar::Octets &arg) const;
  void generate(const Document_path &arg) const;
  void generate(const Placeholder &arg) const;
  void generate(const Mysqlx::Expr::Object &arg) const;
  void generate(const Mysqlx::Expr::Object::ObjectField &arg) const;
  void generate(const Mysqlx::Expr::Array &arg) const;

  template <typename T>
  void generate_for_each(const ::google::protobuf::RepeatedPtrField<T> &list,
                         void (Expression_generator::*generate_fun)(const T&) const,
                         const typename ::google::protobuf::RepeatedPtrField<T>::size_type offset = 0) const;
  void generate_unquote_param(const Mysqlx::Expr::Expr &arg) const;

  void binary_operator(const Mysqlx::Expr::Operator &arg, const char* str) const;
  void unary_operator(const Mysqlx::Expr::Operator &arg, const char* str) const;
  void nullary_operator(const Mysqlx::Expr::Operator &arg, const char* str) const;
  void in_expression(const Mysqlx::Expr::Operator &arg, const char* str) const;
  void like_expression(const Mysqlx::Expr::Operator &arg, const char* str) const;
  void between_expression(const Mysqlx::Expr::Operator &arg, const char* str) const;
  void date_expression(const Mysqlx::Expr::Operator &arg, const char* str) const;
  void cast_expression(const Mysqlx::Expr::Operator &arg) const;
  void binary_expression(const Mysqlx::Expr::Operator &arg, const char* str) const;
  void asterisk_operator(const Mysqlx::Expr::Operator &arg) const;

  Query_string_builder &m_qb;
  const Args &m_args;
  const std::string &m_default_schema;
  const bool &m_is_relational;
};


template<typename T>
void generate_expression(Query_string_builder &qb, const T &expr,
                         const Expression_generator::Args &args,
                         const std::string &default_schema,
                         bool is_relational)
{
  Expression_generator gen(qb, args, default_schema, is_relational);
  gen.feed(expr);
}


template<typename T>
ngs::PFS_string generate_expression(const T &expr,
                                const Expression_generator::Args &args,
                                const std::string &default_schema,
                                bool is_relational)
{
  Query_string_builder qb;
  generate_expression(qb, expr, args, default_schema, is_relational);
  return qb.get();
}


template<typename T>
void generate_expression(Query_string_builder &qb, const T &expr, const std::string &default_schema, bool is_relational)
{
  generate_expression(qb, expr, Expression_generator::Args(), default_schema, is_relational);
}


template<typename T>
ngs::PFS_string generate_expression(const T &expr, const std::string &default_schema, bool is_relational)
{
  return generate_expression(expr, Expression_generator::Args(), default_schema, is_relational);
}

} // namespace xpl

#endif // _XPL_EXPR_GENERATOR_H_