#ifndef QUERY_FIELD_HPP
#define QUERY_FIELD_HPP

#include "matador/sql/any_type.hpp"
#include "matador/sql/any_type_to_visitor.hpp"

#include "matador/utils/types.hpp"

#include <optional>
#include <string>

namespace matador::sql {

enum class field_type {
  Integer,
  FloatingPoint,
  String,
  Boolean,
  Blob,
  Null
};

template < typename Type, typename Enable = void >
struct field_traits;

template<typename Type>
struct field_traits<Type, typename std::enable_if<std::is_integral<Type>::value && !std::is_same<Type, bool>::value>::type>
{
  static field_type type() { return field_type::Integer; }
};

template<typename Type>
struct field_traits<Type, typename std::enable_if<std::is_floating_point<Type>::value>::type>
{
  static field_type type() { return field_type::FloatingPoint; }
};

template<typename Type>
struct field_traits<Type, typename std::enable_if<std::is_same<Type, std::string>::value>::type>
{
  static field_type type() { return field_type::String; }
};

template<typename Type>
struct field_traits<Type, typename std::enable_if<std::is_same<Type, bool>::value>::type>
{
  static field_type type() { return field_type::Boolean; }
};

template<typename Type>
struct field_traits<Type, typename std::enable_if<std::is_same<Type, nullptr_t>::value>::type>
{
  static field_type type() { return field_type::Null; }
};

template<typename Type>
struct field_traits<Type, typename std::enable_if<std::is_same<Type, utils::blob>::value>::type>
{
  static field_type type() { return field_type::Blob; }
};

class field
{
public:
  explicit field(std::string name);
  template<typename Type>
  field(std::string name, Type value)
  : name_(std::move(name))
  , value_(value)
  , type_(field_traits<Type>::type()) {}
  field(const field &x) = default;
  field& operator=(const field &x) = default;
  field(field &&x) noexcept;
  field& operator=(field &&x) noexcept;

  template<typename Type>
  field& operator=(Type value) {
    value_ = std::move(value);
    type_ = field_traits<Type>::type();
    return *this;
  }

  [[nodiscard]] const std::string& name() const;

  template<class Type>
  std::optional<Type> as() const
  {
    any_type_to_visitor<Type> visitor;
    std::visit(visitor, const_cast<any_type&>(value_));
    return visitor.result;
  }

  [[nodiscard]] std::string str() const;

  [[nodiscard]] bool is_integer() const;
  [[nodiscard]] bool is_floating_point() const;
  [[nodiscard]] bool is_bool() const;
  [[nodiscard]] bool is_string() const;
  [[nodiscard]] bool is_blob() const;
  [[nodiscard]] bool is_null() const;

  friend std::ostream& operator<<(std::ostream &out, const field &col);

private:
  std::string name_;
  any_type value_;
  field_type type_;
};

}
#endif //QUERY_FIELD_HPP