daw_from_json.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 "daw/json/impl/version.h"
 
#include "daw/json/daw_from_json_fwd.h"
#include "daw/json/impl/daw_json_parse_class.h"
#include "daw/json/impl/daw_json_parse_value.h"
#include "daw/json/impl/daw_json_value.h"
 
#include <daw/daw_data_end.h>
#include <daw/daw_not_null.h>
#include <daw/traits/daw_traits_conditional.h>
 
#include <daw/stdinc/data_access.h>
#include <daw/stdinc/move_fwd_exch.h>
#include <string_view>
 
namespace daw::json {
  inline namespace DAW_JSON_VER {
 
    template<typename JsonMember, bool KnownBounds, typename String,
             auto... PolicyFlags>
    [[nodiscard]] constexpr auto
    from_json( String &&json_data, options::parse_flags_t<PolicyFlags...> ) {
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
      daw_json_ensure( std::size( json_data ) != 0,
                       ErrorReason::EmptyJSONDocument );
 
      static_assert(
        json_details::has_json_deduced_type_v<JsonMember>,
        "Missing specialization of daw::json::json_data_contract for class "
        "mapping or specialization of daw::json::json_link_basic_type_map" );
      using json_member = json_details::json_deduced_type<JsonMember>;
      using ParsePolicy =
        BasicParsePolicy<options::parse_flags_t<PolicyFlags...>::value>;
 
      using policy_zstring_t = json_details::apply_zstring_policy_option_t<
        ParsePolicy,
        String,
        options::ZeroTerminatedString::yes>;
 
      auto first =
        daw::not_null<typename ParsePolicy::iterator>( std::data( json_data ) );
      auto last = daw::not_null<typename ParsePolicy::iterator>(
        daw::data_end( json_data ) );
      if( first != last and last[-1] == 0 ) {
        --last;
      }
 
      using ParseState =
        daw::conditional_t<policy_zstring_t::is_default_parse_policy,
                           DefaultParsePolicy,
                           policy_zstring_t>;
 
      auto parse_state = ParseState( first.get( ), last.get( ) );
 
      if constexpr( ParseState::must_verify_end_of_data_is_valid ) {
        auto result =
          json_details::parse_value<json_member,
                                    KnownBounds,
                                    json_member::expected_type>( parse_state );
        parse_state.trim_left( );
        daw_json_ensure(
          parse_state.empty( ), ErrorReason::InvalidEndOfValue, parse_state );
        return result;
      } else {
        return json_details::
          parse_value<json_member, KnownBounds, json_member::expected_type>(
            parse_state );
      }
    }
 
    template<typename JsonMember, bool KnownBounds, typename String>
    [[nodiscard]] constexpr auto from_json( String &&json_data ) {
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
      return from_json<JsonMember, KnownBounds>( DAW_FWD( json_data ),
                                                 options::parse_flags<> );
    }
 
    template<typename JsonMember, bool KnownBounds, typename String,
             auto... PolicyFlags>
    [[nodiscard]] constexpr auto
    from_json_insitu( String &&json_data,
                      options::parse_flags_t<PolicyFlags...> ) {
      static_assert( std::is_same_v<decltype( std::data( json_data ) ), char *>,
                     "from_json_insitu requires a mutable character buffer" );
      return from_json<JsonMember, KnownBounds>(
        DAW_FWD( json_data ),
        options::parse_flags<PolicyFlags...,
                             options::AllowStringMutation::yes> );
    }
 
    template<typename JsonMember, bool KnownBounds, typename String>
    [[nodiscard]] constexpr auto from_json_insitu( String &&json_data ) {
      return from_json_insitu<JsonMember, KnownBounds>(
        DAW_FWD( json_data ), options::parse_flags<> );
    }
 
    template<typename JsonMember, bool KnownBounds, typename String,
             typename Allocator, auto... PolicyFlags>
    [[nodiscard]] constexpr auto
    from_json_alloc( String &&json_data, Allocator const &alloc,
                     options::parse_flags_t<PolicyFlags...> ) {
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
      daw_json_ensure( std::size( json_data ) != 0,
                       ErrorReason::EmptyJSONDocument );
 
      using json_member = json_details::json_deduced_type<JsonMember>;
 
      static_assert(
        json_details::has_unnamed_default_type_mapping_v<JsonMember>,
        "Missing specialization of daw::json::json_data_contract for class "
        "mapping or specialization of daw::json::json_link_basic_type_map" );
 
      auto f = daw::not_null<char const *>( std::data( json_data ) );
      auto l = daw::not_null<char const *>( daw::data_end( json_data ) );
      Allocator a = alloc;
 
      using ParsePolicy =
        BasicParsePolicy<options::parse_flags_t<PolicyFlags...>::value>;
 
      using ParseState = json_details::apply_zstring_policy_option_t<
        ParsePolicy,
        String,
        options::ZeroTerminatedString::yes>;
 
      auto parse_state = ParseState::with_allocator( f.get( ), l.get( ), a );
      if constexpr( ParseState::must_verify_end_of_data_is_valid ) {
        auto result =
          json_details::parse_value<json_member,
                                    KnownBounds,
                                    json_member::expected_type>( parse_state );
        parse_state.trim_left( );
        daw_json_ensure(
          parse_state.empty( ), ErrorReason::InvalidEndOfValue, parse_state );
        return result;
      } else {
        return json_details::
          parse_value<json_member, KnownBounds, json_member::expected_type>(
            parse_state );
      }
    }
 
    template<typename JsonMember, bool KnownBounds, typename String,
             typename Allocator>
    [[nodiscard]] constexpr auto from_json_alloc( String &&json_data,
                                                  Allocator const &alloc ) {
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
      return from_json_alloc<JsonMember, KnownBounds>(
        DAW_FWD( json_data ), alloc, options::parse_flags<> );
    }
 
    template<typename JsonMember, bool KnownBounds, typename String,
             auto... PolicyFlags>
    [[nodiscard]] constexpr auto
    from_json( String &&json_data, std::string_view member_path,
               options::parse_flags_t<PolicyFlags...> ) {
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
 
      daw_json_ensure( std::size( json_data ) != 0,
                       ErrorReason::EmptyJSONDocument );
      daw_json_ensure( std::data( json_data ) != nullptr,
                       ErrorReason::EmptyJSONPath );
      daw_json_ensure( std::data( member_path ) != nullptr,
                       ErrorReason::EmptyJSONPath );
 
      using json_member = json_details::json_deduced_type<JsonMember>;
      static_assert(
        json_details::has_unnamed_default_type_mapping_v<JsonMember>,
        "Missing specialization of daw::json::json_data_contract for class "
        "mapping or specialization of daw::json::json_link_basic_type_map" );
 
      using ParsePolicy =
        BasicParsePolicy<options::parse_flags_t<PolicyFlags...>::value>;
 
      using policy_zstring_t = json_details::apply_zstring_policy_option_t<
        ParsePolicy,
        String,
        options::ZeroTerminatedString::yes>;
 
      using ParseState =
        daw::conditional_t<policy_zstring_t::is_default_parse_policy,
                           DefaultParsePolicy,
                           policy_zstring_t>;
      auto first = std::data( json_data );
      auto last = daw::data_end( json_data );
      if( first != last and last[-1] == 0 ) {
        --last;
      }
      auto jv = basic_json_value( ParseState( first, last ) );
      jv = jv.find_member( member_path );
 
      if constexpr( json_details::is_json_nullable_v<json_member> ) {
        if( not jv ) {
          return json_details::construct_nullable_empty<
            json_details::json_constructor_t<json_member>>( );
        }
      } else {
        daw_json_ensure( jv, ErrorReason::JSONPathNotFound );
      }
      auto parse_state = jv.get_raw_state( );
      if constexpr( ParseState::must_verify_end_of_data_is_valid ) {
        auto result =
          json_details::parse_value<json_member,
                                    KnownBounds,
                                    json_member::expected_type>( parse_state );
        parse_state.trim_left( );
        daw_json_ensure(
          parse_state.empty( ), ErrorReason::InvalidEndOfValue, parse_state );
        return result;
      } else {
        return json_details::
          parse_value<json_member, KnownBounds, json_member::expected_type>(
            parse_state );
      }
    }
 
    template<typename JsonMember, bool KnownBounds, typename String>
    [[nodiscard]] constexpr auto from_json( String &&json_data,
                                            std::string_view member_path ) {
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
 
      return from_json<JsonMember, KnownBounds>(
        DAW_FWD( json_data ), member_path, options::parse_flags<> );
    }
 
    template<typename JsonMember, bool KnownBounds, typename String,
             typename Allocator, auto... PolicyFlags>
    [[nodiscard]] constexpr auto
    from_json_alloc( String &&json_data, std::string_view member_path,
                     Allocator const &alloc,
                     options::parse_flags_t<PolicyFlags...> ) {
 
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
      daw_json_ensure( std::size( json_data ) != 0,
                       ErrorReason::EmptyJSONDocument );
      daw_json_ensure( std::data( json_data ) != nullptr,
                       ErrorReason::EmptyJSONDocument );
      daw_json_ensure( std::data( member_path ) != nullptr,
                       ErrorReason::EmptyJSONPath );
 
      using json_member = json_details::json_deduced_type<JsonMember>;
      static_assert(
        json_details::has_unnamed_default_type_mapping_v<JsonMember>,
        "Missing specialization of daw::json::json_data_contract for class "
        "mapping or specialization of daw::json::json_link_basic_type_map" );
 
      using ParsePolicy =
        BasicParsePolicy<options::parse_flags_t<PolicyFlags...>::value>;
 
      using ParseState = json_details::apply_zstring_policy_option_t<
        ParsePolicy,
        String,
        options::ZeroTerminatedString::yes>;
 
      auto first = std::data( json_data );
      auto last = daw::data_end( json_data );
      if( first != last and last[-1] == 0 ) {
        --last;
      }
      auto jv = basic_json_value(
        ParseState( first, last, first, last ).with_allocator( alloc ) );
      jv = jv.find_member( member_path );
 
      if constexpr( json_details::is_json_nullable_v<json_member> ) {
        if( not jv ) {
          return json_details::construct_nullable_empty<
            json_details::json_constructor_t<json_member>>( );
        }
      } else {
        daw_json_ensure( jv, ErrorReason::JSONPathNotFound );
      }
      auto parse_state = jv.get_raw_state( );
      if constexpr( ParseState::must_verify_end_of_data_is_valid ) {
        auto result =
          json_details::parse_value<json_member,
                                    KnownBounds,
                                    json_member::expected_type>( parse_state );
        parse_state.trim_left( );
        daw_json_ensure(
          parse_state.empty( ), ErrorReason::InvalidEndOfValue, parse_state );
        return result;
      } else {
        return json_details::
          parse_value<json_member, KnownBounds, json_member::expected_type>(
            parse_state );
      }
    }
 
    template<typename JsonMember, bool KnownBounds, typename String,
             typename Allocator>
    [[nodiscard]] constexpr auto from_json_alloc( String &&json_data,
                                                  std::string_view member_path,
                                                  Allocator const &alloc ) {
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
 
      return from_json_alloc<JsonMember, KnownBounds>(
        DAW_FWD( json_data ), member_path, alloc, options::parse_flags<> );
    }
 
    template<typename JsonMember, bool KnownBounds, json_options_t P,
             typename Allocator, auto... PolicyFlags>
    [[nodiscard]] constexpr auto
    from_json( basic_json_value<P, Allocator> value,
               options::parse_flags_t<PolicyFlags...> ) {
      using json_member = json_details::json_deduced_type<JsonMember>;
      static_assert(
        json_details::has_unnamed_default_type_mapping_v<JsonMember>,
        "Missing specialization of daw::json::json_data_contract for class "
        "mapping or specialization of daw::json::json_link_basic_type_map" );
      using ParsePolicy =
        typename BasicParsePolicy<P, Allocator>::template SetPolicyOptions<
          PolicyFlags...>;
      using ParseState =
        daw::conditional_t<ParsePolicy::is_default_parse_policy,
                           DefaultParsePolicy,
                           ParsePolicy>;
      auto const old_parse_state = value.get_raw_state( );
      auto parse_state = ParseState( old_parse_state.first,
                                     old_parse_state.last,
                                     old_parse_state.class_first,
                                     old_parse_state.class_last,
                                     old_parse_state.get_allocator( ) );
 
      return json_details::
        parse_value<json_member, KnownBounds, json_member::expected_type>(
          parse_state );
    }
 
    template<typename JsonMember, bool KnownBounds, json_options_t PolicyFlags,
             typename Allocator>
    [[nodiscard]] constexpr auto
    from_json( basic_json_value<PolicyFlags, Allocator> value ) {
 
      return from_json<JsonMember, KnownBounds>( std::move( value ),
                                                 options::parse_flags<> );
    }
 
    template<typename JsonMember, bool KnownBounds, json_options_t P,
             typename Allocator, auto... PolicyFlags>
    [[nodiscard]] constexpr auto
    from_json( basic_json_value<P, Allocator> value,
               std::string_view member_path,
               options::parse_flags_t<PolicyFlags...> ) {
      using json_member = json_details::json_deduced_type<JsonMember>;
      static_assert(
        json_details::has_unnamed_default_type_mapping_v<JsonMember>,
        "Missing specialization of daw::json::json_data_contract for class "
        "mapping or specialization of daw::json::json_link_basic_type_map" );
      using ParsePolicy =
        BasicParsePolicy<options::parse_flags_t<PolicyFlags...>::value>;
      auto const old_parse_state = value.get_raw_state( );
      using ParseState =
        daw::conditional_t<ParsePolicy::is_default_parse_policy,
                           DefaultParsePolicy,
                           ParsePolicy>;
      auto jv =
        basic_json_value( ParseState( old_parse_state.first,
                                      old_parse_state.last,
                                      old_parse_state.class_first,
                                      old_parse_state.class_last,
                                      old_parse_state.get_allocator( ) ) );
 
      jv = jv.find_member( member_path );
 
      if constexpr( json_details::is_json_nullable_v<json_member> ) {
        if( not jv ) {
          return json_details::construct_nullable_empty<
            json_details::json_constructor_t<json_member>>( );
        }
      } else {
        daw_json_ensure( jv, ErrorReason::JSONPathNotFound );
      }
      auto parse_state = jv.get_raw_state( );
      return json_details::
        parse_value<json_member, KnownBounds, json_member::expected_type>(
          parse_state );
    }
 
    template<typename JsonMember, bool KnownBounds, json_options_t PolicyFlags,
             typename Allocator>
    [[nodiscard]] constexpr auto from_json( basic_json_value<PolicyFlags> value,
                                            std::string_view member_path ) {
      return from_json<JsonMember, KnownBounds>(
        std::move( value ), member_path, options::parse_flags<> );
    }
 
    template<typename JsonElement, typename Container, typename Constructor,
             bool KnownBounds, typename String, auto... PolicyFlags>
    [[nodiscard]] constexpr Container
    from_json_array( String &&json_data,
                     options::parse_flags_t<PolicyFlags...> ) {
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
 
      daw_json_ensure( std::size( json_data ) != 0,
                       ErrorReason::EmptyJSONDocument );
      daw_json_ensure( std::data( json_data ) != nullptr,
                       ErrorReason::EmptyJSONPath );
      static_assert(
        json_details::has_unnamed_default_type_mapping_v<JsonElement>,
        "Missing specialization of daw::json::json_data_contract for class "
        "mapping or specialization of daw::json::json_link_basic_type_map" );
      using element_type = json_details::json_deduced_type<JsonElement>;
      static_assert( not std::is_same_v<element_type, void>,
                     "Unknown JsonElement type." );
 
      using parser_t =
        json_base::json_array<JsonElement, Container, Constructor>;
 
      using ParsePolicy =
        BasicParsePolicy<options::parse_flags_t<PolicyFlags...>::value>;
 
      using policy_zstring_t = json_details::apply_zstring_policy_option_t<
        ParsePolicy,
        String,
        options::ZeroTerminatedString::yes>;
 
      using ParseState =
        daw::conditional_t<policy_zstring_t::is_default_parse_policy,
                           DefaultParsePolicy,
                           policy_zstring_t>;
      auto parse_state =
        ParseState{ std::data( json_data ), daw::data_end( json_data ) };
 
      parse_state.trim_left_unchecked( );
#if defined( DAW_JSON_BUGFIX_FROM_JSON_001 )
      daw_json_ensure( parse_state.is_opening_bracket_checked( ),
                       ErrorReason::InvalidArrayStart,
                       parse_state );
#else
      daw_json_assert_weak( parse_state.is_opening_bracket_checked( ),
                            ErrorReason::InvalidArrayStart,
                            parse_state );
#endif
      if constexpr( ParseState::must_verify_end_of_data_is_valid ) {
        auto result =
          json_details::parse_value_array<parser_t, KnownBounds>( parse_state );
        parse_state.trim_left( );
        daw_json_ensure(
          parse_state.empty( ), ErrorReason::InvalidEndOfValue, parse_state );
        return result;
      } else {
        return json_details::parse_value_array<parser_t, KnownBounds>(
          parse_state );
      }
    }
 
    template<typename JsonElement, typename Container, typename Constructor,
             bool KnownBounds, typename String>
    [[nodiscard]] constexpr Container from_json_array( String &&json_data ) {
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
      return from_json_array<JsonElement, Container, Constructor, KnownBounds>(
        DAW_FWD( json_data ), options::parse_flags<> );
    }
 
    template<typename JsonElement, typename Container, typename Constructor,
             bool KnownBounds, typename String, auto... PolicyFlags>
    [[nodiscard]] constexpr Container
    from_json_array( String &&json_data, std::string_view member_path,
                     options::parse_flags_t<PolicyFlags...> ) {
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
 
      daw_json_ensure( std::size( json_data ) != 0,
                       ErrorReason::EmptyJSONDocument );
      daw_json_ensure( std::data( json_data ) != nullptr,
                       ErrorReason::EmptyJSONPath );
      daw_json_ensure( std::data( member_path ) != nullptr,
                       ErrorReason::EmptyJSONPath );
      static_assert(
        json_details::has_unnamed_default_type_mapping_v<JsonElement>,
        "Missing specialization of daw::json::json_data_contract for class "
        "mapping or specialization of daw::json::json_link_basic_type_map" );
      using element_type = json_details::json_deduced_type<JsonElement>;
      static_assert( not std::is_same_v<element_type, void>,
                     "Unknown JsonElement type." );
 
      using parser_t =
        json_base::json_array<JsonElement, Container, Constructor>;
 
      using ParsePolicy =
        BasicParsePolicy<options::parse_flags_t<PolicyFlags...>::value>;
 
      using policy_zstring_t = json_details::apply_zstring_policy_option_t<
        ParsePolicy,
        String,
        options::ZeroTerminatedString::yes>;
 
      using ParseState =
        daw::conditional_t<policy_zstring_t::is_default_parse_policy,
                           DefaultParsePolicy,
                           policy_zstring_t>;
      auto first = std::data( json_data );
      auto last = daw::data_end( json_data );
      if( first != last and last[-1] == 0 ) {
        --last;
      }
      auto jv = basic_json_value( ParseState( first, last ) );
      jv = jv.find_member( member_path );
 
      if constexpr( json_details::is_json_nullable_v<parser_t> ) {
        if( not jv ) {
          return json_details::construct_nullable_empty<
            json_details::json_constructor_t<parser_t>>( );
        }
      } else {
        daw_json_ensure( jv, ErrorReason::JSONPathNotFound );
      }
      auto parse_state = jv.get_raw_state( );
      parse_state.trim_left_unchecked( );
#if defined( DAW_JSON_BUGFIX_FROM_JSON_001 )
      daw_json_ensure( parse_state.is_opening_bracket_checked( ),
                       ErrorReason::InvalidArrayStart,
                       parse_state );
#else
      daw_json_assert_weak( parse_state.is_opening_bracket_checked( ),
                            ErrorReason::InvalidArrayStart,
                            parse_state );
#endif
      if constexpr( ParseState::must_verify_end_of_data_is_valid ) {
        auto result =
          json_details::parse_value_array<parser_t, KnownBounds>( parse_state );
        parse_state.trim_left( );
        daw_json_ensure(
          parse_state.empty( ), ErrorReason::InvalidEndOfValue, parse_state );
        return result;
      } else {
        return json_details::parse_value_array<parser_t, KnownBounds>(
          parse_state );
      }
    }
 
    template<typename JsonElement, typename Container, typename Constructor,
             bool KnownBounds, typename String>
    [[nodiscard]] constexpr Container
    from_json_array( String &&json_data, std::string_view member_path ) {
      static_assert(
        json_details::is_string_view_like_v<String>,
        "String type must have a be a contiguous range of Characters" );
 
      return from_json_array<JsonElement, Container, Constructor, KnownBounds>(
        DAW_FWD( json_data ), member_path, options::parse_flags<> );
    }
  } // namespace DAW_JSON_VER
} // namespace daw::json