daw_json_serialize_policy.h

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// Copyright (c) Darrell Wright
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE or copy at http://www.boost.org/LICENSE_1_0.txt)
//
// Official repository: https://github.com/beached/daw_json_link
//
 
#pragma once
 
#include "version.h"
 
#include "daw_json_option_bits.h"
#include "daw_json_parse_options_impl.h"
#include "daw_json_serialize_options_impl.h"
#include "daw_json_serialize_policy_details.h"
#include <daw/json/concepts/daw_writable_output.h>
 
#include <daw/daw_move.h>
 
#include <cstddef>
#include <iterator>
#include <memory>
 
namespace daw::json {
  inline namespace DAW_JSON_VER {
    /***
     * Create the parser options flag for BasicParsePolicy
     * @tparam Policies Policy types that satisfy the `is_policy_flag` trait.
     * @param policies A list of parser options to change from the defaults.
     * @return A json_options_t that encodes the options for the parser
     */
    template<typename... Policies>
    constexpr json_options_t serialize_options( Policies... policies ) {
      static_assert( json_details::are_option_flags<Policies...>,
                     "Only registered policy types are allowed" );
      auto result = json_details::serialization::default_policy_flag;
      if constexpr( sizeof...( Policies ) > 0 ) {
        result |=
          ( json_details::serialization::set_bits_for( policies ) | ... );
      }
      return result;
    }
    namespace json_details {
      template<typename T>
      DAW_ATTRIB_INLINE constexpr daw::string_view as_sv( T const &value ) {
        if constexpr( std::is_same_v<char, DAW_TYPEOF( value )> ) {
          return daw::string_view( &value, 1 );
        } else {
          return daw::string_view( value );
        }
      }
    } // namespace json_details
 
    template<typename WritableType,
             json_options_t PolicyFlags =
               json_details::serialization::default_policy_flag>
    struct serialization_policy {
      static_assert(
        concepts::is_writable_output_type_v<WritableType>,
        "Output type does not have a writeable_output_trait specialization" );
      using i_am_a_serialization_policy = void;
      WritableType *m_writable;
 
      DAW_ATTRIB_INLINE static DAW_CONSTEVAL json_options_t policy_flags( ) {
        return PolicyFlags;
      }
 
      std::size_t indentation_level = 0;
 
      DAW_ATTRIB_INLINE constexpr WritableType const &get( ) const {
        return *m_writable;
      }
 
      DAW_ATTRIB_INLINE constexpr WritableType &get( ) {
        return *m_writable;
      }
 
      DAW_ATTRIB_INLINE explicit constexpr serialization_policy( WritableType &writable )
        : m_writable( std::addressof( writable ) ) {}
 
      static constexpr options::SerializationFormat serialization_format =
        json_details::serialization::get_bits_for<options::SerializationFormat>(
          PolicyFlags );
 
      static constexpr options::IndentationType indentation_type =
        json_details::serialization::get_bits_for<options::IndentationType>(
          PolicyFlags );
 
      static constexpr options::RestrictedStringOutput
        restricted_string_output = json_details::serialization::get_bits_for<
          options::RestrictedStringOutput>( PolicyFlags );
 
      static constexpr options::NewLineDelimiter newline_delimiter =
        json_details::serialization::get_bits_for<options::NewLineDelimiter>(
          PolicyFlags );
 
      static constexpr options::OutputTrailingComma output_trailing_comma =
        json_details::serialization::get_bits_for<options::OutputTrailingComma>(
          PolicyFlags );
 
      DAW_ATTRIB_INLINE constexpr void add_indent( ) {
        if constexpr( serialization_format !=
                      options::SerializationFormat::Minified ) {
          ++indentation_level;
        }
      }
 
      DAW_ATTRIB_INLINE constexpr void del_indent( ) {
        if constexpr( serialization_format !=
                      options::SerializationFormat::Minified ) {
          --indentation_level;
        }
      }
 
      DAW_ATTRIB_INLINE constexpr void output_indent( ) {
        if constexpr( serialization_format !=
                      options::SerializationFormat::Minified ) {
          constexpr std::string_view indent =
            json_details::serialization::generate_indent<serialization_format,
                                                         indentation_type>;
          if( not indent.empty( ) ) {
            for( std::size_t n = 0; n < indentation_level; ++n ) {
              write_output( *m_writable, indent );
            }
          }
        }
      }
 
      static constexpr std::string_view newline =
        newline_delimiter == options::NewLineDelimiter::n ? "\n" : "\r\n";
 
      DAW_ATTRIB_INLINE constexpr void output_newline( ) {
        if constexpr( serialization_format !=
                      options::SerializationFormat::Minified ) {
          write_output( *m_writable, newline );
        }
      }
 
      static constexpr daw::string_view space =
        serialization_format != options::SerializationFormat::Minified
          ? " "
          : nullptr;
 
      DAW_ATTRIB_INLINE constexpr void next_member( ) {
        output_newline( );
        output_indent( );
      }
 
      template<typename ContiguousCharRange, typename... ContiguousCharRanges>
      DAW_ATTRIB_FLATINLINE constexpr void
      write( ContiguousCharRange const &chr,
             ContiguousCharRanges const &...chrs ) {
 
        write_output( *m_writable, json_details::as_sv( chr ),
                      json_details::as_sv( chrs )... );
      }
 
      DAW_ATTRIB_INLINE constexpr void copy_buffer( char const *first,
                                                    char const *last ) {
        write(
          daw::string_view( first, static_cast<std::size_t>( last - first ) ) );
      }
 
      DAW_ATTRIB_FLATINLINE constexpr void put( char c ) {
        put_output( *m_writable, c );
      }
 
      DAW_ATTRIB_INLINE constexpr serialization_policy &operator=( char c ) {
        put_output( *m_writable, c );
        return *this;
      }
 
      DAW_ATTRIB_INLINE constexpr serialization_policy &operator*( ) {
        return *this;
      }
 
      DAW_ATTRIB_INLINE constexpr serialization_policy &operator++( ) {
        return *this;
      }
 
      DAW_ATTRIB_INLINE constexpr serialization_policy operator++( int ) & {
        return *this;
      }
    };
 
    template<typename, typename...>
    inline constexpr bool is_serialization_policy_v = false;
 
    template<typename OutputIterator, json_options_t PolicyFlags>
    inline constexpr bool is_serialization_policy_v<
      serialization_policy<OutputIterator, PolicyFlags>> = true;
  } // namespace DAW_JSON_VER
} // namespace daw::json