path: root/src/openvic-dataloader/detail/Convert.hpp

#pragma once

#include <cstddef>
#include <string_view>
#include <type_traits>

#include <lexy/_detail/config.hpp>
#include <lexy/callback/string.hpp>
#include <lexy/code_point.hpp>
#include <lexy/dsl/option.hpp>
#include <lexy/dsl/symbol.hpp>
#include <lexy/encoding.hpp>
#include <lexy/input/base.hpp>
#include <lexy/input/file.hpp>
#include <lexy/input/string_input.hpp>
#include <lexy/lexeme.hpp>

#include "openvic-dataloader/detail/Encoding.hpp"

#include "ParseState.hpp" // IWYU pragma: keep
#include "detail/InternalConcepts.hpp"
#include "detail/dsl.hpp"
#include "v2script/ParseState.hpp"

namespace ovdl::convert {
   struct map_value {
      std::string_view _value;

      constexpr map_value() noexcept : _value("") {}
      constexpr map_value(std::nullptr_t) noexcept : _value("\0", 1) {}
      constexpr explicit map_value(std::string_view val) noexcept : _value(val) {}

      static constexpr map_value invalid_value() noexcept {
         return map_value(nullptr);
      }

      constexpr bool is_invalid() const noexcept {
         return !_value.empty() && _value[0] == '\0';
      }

      constexpr bool is_pass() const noexcept {
         return _value.empty();
      }

      constexpr bool is_valid() const noexcept {
         return !_value.empty() && _value[0] != '\0';
      }

      constexpr explicit operator bool() const noexcept {
         return is_valid();
      }
   };

   template<typename T>
   concept IsConverter = requires(unsigned char c, lexy::_pr<lexy::deduce_encoding<char>>& reader) {
      { T::try_parse(reader) } -> std::same_as<map_value>;
   };

   struct Utf8 {
      static constexpr auto map = lexy::symbol_table<std::string_view>;

      template<typename Reader>
      static constexpr map_value try_parse(Reader& reader) {
         return {};
      }
   };
   static_assert(IsConverter<Utf8>);

   struct Windows1252 {
      static constexpr auto map = lexy::symbol_table<std::string_view> //
                              .map<'\x80'>("€")
                              .map<'\x82'>("‚")
                              .map<'\x83'>("ƒ")
                              .map<'\x84'>("„")
                              .map<'\x85'>("…")
                              .map<'\x86'>("†")
                              .map<'\x87'>("‡")
                              .map<'\x88'>("ˆ")
                              .map<'\x89'>("‰")
                              .map<'\x8A'>("Š")
                              .map<'\x8B'>("‹")
                              .map<'\x8C'>("Œ")
                              .map<'\x8E'>("Ž")

                              .map<'\x91'>("‘")
                              .map<'\x92'>("’")
                              .map<'\x93'>("“")
                              .map<'\x94'>("”")
                              .map<'\x95'>("•")
                              .map<'\x96'>("–")
                              .map<'\x97'>("—")
                              .map<'\x98'>("˜")
                              .map<'\x99'>("™")
                              .map<'\x9A'>("š")
                              .map<'\x9B'>("›")
                              .map<'\x9C'>("œ")
                              .map<'\x9E'>("ž")
                              .map<'\x9F'>("Ÿ")

                              .map<'\xA0'>(" ")
                              .map<'\xA1'>("¡")
                              .map<'\xA2'>("¢")
                              .map<'\xA3'>("£")
                              .map<'\xA4'>("¤")
                              .map<'\xA5'>("¥")
                              .map<'\xA6'>("¦")
                              .map<'\xA7'>("§")
                              .map<'\xA8'>("¨")
                              .map<'\xA9'>("©")
                              .map<'\xAA'>("ª")
                              .map<'\xAB'>("«")
                              .map<'\xAC'>("¬")
                              .map<'\xAD'>("­") // Soft Hyphen
                              .map<'\xAE'>("®")
                              .map<'\xAF'>("¯")

                              .map<'\xB0'>("°")
                              .map<'\xB1'>("±")
                              .map<'\xB2'>("²")
                              .map<'\xB3'>("³")
                              .map<'\xB4'>("´")
                              .map<'\xB5'>("µ")
                              .map<'\xB6'>("¶")
                              .map<'\xB7'>("·")
                              .map<'\xB8'>("¸")
                              .map<'\xB9'>("¹")
                              .map<'\xBA'>("º")
                              .map<'\xBB'>("»")
                              .map<'\xBC'>("¼")
                              .map<'\xBD'>("½")
                              .map<'\xBE'>("¾")
                              .map<'\xBF'>("¿")

                              .map<'\xC0'>("À")
                              .map<'\xC1'>("Á")
                              .map<'\xC2'>("Â")
                              .map<'\xC3'>("Ã")
                              .map<'\xC4'>("Ä")
                              .map<'\xC5'>("Å")
                              .map<'\xC6'>("Æ")
                              .map<'\xC7'>("Ç")
                              .map<'\xC8'>("È")
                              .map<'\xC9'>("É")
                              .map<'\xCA'>("Ê")
                              .map<'\xCB'>("Ë")
                              .map<'\xCC'>("Ì")
                              .map<'\xCD'>("Í")
                              .map<'\xCE'>("Î")
                              .map<'\xCF'>("Ï")

                              .map<'\xD0'>("Ð")
                              .map<'\xD1'>("Ñ")
                              .map<'\xD2'>("Ò")
                              .map<'\xD3'>("Ó")
                              .map<'\xD4'>("Ô")
                              .map<'\xD5'>("Õ")
                              .map<'\xD6'>("Ö")
                              .map<'\xD7'>("×")
                              .map<'\xD8'>("Ø")
                              .map<'\xD9'>("Ù")
                              .map<'\xDA'>("Ú")
                              .map<'\xDB'>("Û")
                              .map<'\xDC'>("Ü")
                              .map<'\xDD'>("Ý")
                              .map<'\xDE'>("Þ")
                              .map<'\xDF'>("ß")

                              .map<'\xE0'>("à")
                              .map<'\xE1'>("á")
                              .map<'\xE2'>("â")
                              .map<'\xE3'>("ã")
                              .map<'\xE4'>("ä")
                              .map<'\xE5'>("å")
                              .map<'\xE6'>("æ")
                              .map<'\xE7'>("ç")
                              .map<'\xE8'>("è")
                              .map<'\xE9'>("é")
                              .map<'\xEA'>("ê")
                              .map<'\xEB'>("ë")
                              .map<'\xEC'>("ì")
                              .map<'\xED'>("í")
                              .map<'\xEE'>("î")
                              .map<'\xEF'>("ï")

                              .map<'\xF0'>("ð")
                              .map<'\xF1'>("ñ")
                              .map<'\xF2'>("ò")
                              .map<'\xF3'>("ó")
                              .map<'\xF4'>("ô")
                              .map<'\xF5'>("õ")
                              .map<'\xF6'>("ö")
                              .map<'\xF7'>("÷")
                              .map<'\xF8'>("ø")
                              .map<'\xF9'>("ù")
                              .map<'\xFA'>("ú")
                              .map<'\xFB'>("û")
                              .map<'\xFC'>("ü")
                              .map<'\xFD'>("ý")
                              .map<'\xFE'>("þ")
                              .map<'\xFF'>("ÿ")

                              // Paradox being special, invalid Windows-1252
                              // Used for (semantically incorrect) Polish localization TODOs
                              .map<'\x8F'>("Ę");

      template<typename Reader>
      static constexpr map_value try_parse(Reader& reader) {
         auto index = map.try_parse(reader);
         if (index) {
            return map_value(map[index]);
         } else if (*reader.position() < 0) {
            return map_value::invalid_value();
         }
         return {};
      }
   };
   static_assert(IsConverter<Windows1252>);

   struct Windows1251 {
      static constexpr auto map = lexy::symbol_table<std::string_view> //
                              .map<'\x80'>("Ђ")
                              .map<'\x81'>("Ѓ")
                              .map<'\x82'>("‚")
                              .map<'\x83'>("ѓ")
                              .map<'\x84'>("„")
                              .map<'\x85'>("…")
                              .map<'\x86'>("†")
                              .map<'\x87'>("‡")
                              .map<'\x88'>("€")
                              .map<'\x89'>("‰")
                              .map<'\x8A'>("Љ")
                              .map<'\x8B'>("‹")
                              .map<'\x8C'>("Њ")
                              .map<'\x8D'>("Ќ")
                              .map<'\x8E'>("Ћ")
                              .map<'\x8F'>("Џ")

                              .map<'\x90'>("ђ")
                              .map<'\x91'>("‘")
                              .map<'\x92'>("’")
                              .map<'\x93'>("“")
                              .map<'\x94'>("”")
                              .map<'\x95'>("•")
                              .map<'\x96'>("–")
                              .map<'\x97'>("—")
                              .map<'\x99'>("™")
                              .map<'\x9A'>("љ")
                              .map<'\x9B'>("›")
                              .map<'\x9C'>("њ")
                              .map<'\x9D'>("ќ")
                              .map<'\x9E'>("ћ")
                              .map<'\x9F'>("џ")

                              .map<'\xA0'>(" ")
                              .map<'\xA1'>("Ў")
                              .map<'\xA2'>("ў")
                              .map<'\xA3'>("Ј")
                              .map<'\xA4'>("¤")
                              .map<'\xA5'>("Ґ")
                              .map<'\xA6'>("¦")
                              .map<'\xA7'>("§")
                              .map<'\xA8'>("Ё")
                              .map<'\xA9'>("©")
                              .map<'\xAA'>("Є")
                              .map<'\xAB'>("«")
                              .map<'\xAC'>("¬")
                              .map<'\xAD'>("­") // Soft Hyphen
                              .map<'\xAE'>("®")
                              .map<'\xAF'>("Ї")

                              .map<'\xB0'>("°")
                              .map<'\xB1'>("±")
                              .map<'\xB2'>("І")
                              .map<'\xB3'>("і")
                              .map<'\xB4'>("ґ")
                              .map<'\xB5'>("µ")
                              .map<'\xB6'>("¶")
                              .map<'\xB7'>("·")
                              .map<'\xB8'>("ё")
                              .map<'\xB9'>("№")
                              .map<'\xBA'>("є")
                              .map<'\xBB'>("»")
                              .map<'\xBC'>("ј")
                              .map<'\xBD'>("Ѕ")
                              .map<'\xBE'>("ѕ")
                              .map<'\xBF'>("ї")

                              .map<'\xC0'>("А")
                              .map<'\xC1'>("Б")
                              .map<'\xC2'>("В")
                              .map<'\xC3'>("Г")
                              .map<'\xC4'>("Д")
                              .map<'\xC5'>("Е")
                              .map<'\xC6'>("Ж")
                              .map<'\xC7'>("З")
                              .map<'\xC8'>("И")
                              .map<'\xC9'>("Й")
                              .map<'\xCA'>("К")
                              .map<'\xCB'>("Л")
                              .map<'\xCC'>("М")
                              .map<'\xCD'>("Н")
                              .map<'\xCE'>("О")
                              .map<'\xCF'>("П")

                              .map<'\xD0'>("Р")
                              .map<'\xD1'>("С")
                              .map<'\xD2'>("Т")
                              .map<'\xD3'>("У")
                              .map<'\xD4'>("Ф")
                              .map<'\xD5'>("Х")
                              .map<'\xD6'>("Ц")
                              .map<'\xD7'>("Ч")
                              .map<'\xD8'>("Ш")
                              .map<'\xD9'>("Щ")
                              .map<'\xDA'>("Ъ")
                              .map<'\xDB'>("Ы")
                              .map<'\xDC'>("Ь")
                              .map<'\xDD'>("Э")
                              .map<'\xDE'>("Ю")
                              .map<'\xDF'>("Я")

                              .map<'\xE0'>("а")
                              .map<'\xE1'>("б")
                              .map<'\xE2'>("в")
                              .map<'\xE3'>("г")
                              .map<'\xE4'>("д")
                              .map<'\xE5'>("е")
                              .map<'\xE6'>("ж")
                              .map<'\xE7'>("з")
                              .map<'\xE8'>("и")
                              .map<'\xE9'>("й")
                              .map<'\xEA'>("к")
                              .map<'\xEB'>("л")
                              .map<'\xEC'>("м")
                              .map<'\xED'>("н")
                              .map<'\xEE'>("о")
                              .map<'\xEF'>("п")

                              .map<'\xF0'>("р")
                              .map<'\xF1'>("с")
                              .map<'\xF2'>("т")
                              .map<'\xF3'>("у")
                              .map<'\xF4'>("ф")
                              .map<'\xF5'>("х")
                              .map<'\xF6'>("ц")
                              .map<'\xF7'>("ч")
                              .map<'\xF8'>("ш")
                              .map<'\xF9'>("щ")
                              .map<'\xFA'>("ъ")
                              .map<'\xFB'>("ы")
                              .map<'\xFC'>("ь")
                              .map<'\xFD'>("э")
                              .map<'\xFE'>("ю")
                              .map<'\xFF'>("я");

      template<typename Reader>
      static constexpr map_value try_parse(Reader& reader) {
         auto index = map.try_parse(reader);
         if (index) {
            return map_value(map[index]);
         } else if (*reader.position() < 0) {
            return map_value::invalid_value();
         }
         return {};
      }
   };
   static_assert(IsConverter<Windows1251>);

   template<typename Reader>
   constexpr map_value try_parse_map(detail::Encoding&& encoding, Reader& reader) {
      switch (encoding) {
         case detail::Encoding::Unknown:
         case detail::Encoding::Ascii:
         case detail::Encoding::Utf8: return Utf8::try_parse(reader);
         case detail::Encoding::Windows1251: return Windows1251::try_parse(reader);
         case detail::Encoding::Windows1252: return Windows1252::try_parse(reader);
      }
      ovdl::detail::unreachable();
   }

   template<typename String>
   using _string_char_type = LEXY_DECAY_DECLTYPE(LEXY_DECLVAL(String)[0]);

   template<typename T, typename CharT>
   concept IsErrorHandler =
      std::is_convertible_v<CharT, char> //
      && requires(T t, ovdl::v2script::ast::ParseState& state, lexy::_pr<lexy::deduce_encoding<CharT>> reader) {
            { T::on_invalid_character(state, reader) };
         };

   struct EmptyHandler {
      static constexpr void on_invalid_character(detail::IsStateType auto& state, auto reader) {}
   };

   template<typename String,
      IsErrorHandler<_string_char_type<String>> Error = EmptyHandler>
   constexpr auto convert_as_string =
      dsl::sink<String>(
         lexy::fold_inplace<String>(
            std::initializer_list<_string_char_type<String>> {}, //
            []<typename CharT, typename = decltype(LEXY_DECLVAL(String).push_back(CharT()))>(String& result, detail::IsStateType auto& state, CharT c) {
               if constexpr (std::is_convertible_v<CharT, char>) {
                  switch (state.encoding()) {
                     using enum ovdl::detail::Encoding;
                     case Ascii:
                     case Utf8:
                        break;
                     // Skip Ascii and Utf8 encoding
                     default: {
                        // If within ASCII range
                        if (c >= CharT {}) {
                           break;
                        }

                        map_value val = {};
                        CharT char_array[] { c, CharT() };
                        auto input = lexy::range_input(&char_array[0], &char_array[1]);
                        auto reader = input.reader();

                        // prefer preserving unknown conversion maps, least things will work, they'll just probably display wrong
                        // map = make_map_from(state.encoding(), c);
                        val = try_parse_map(state.encoding(), reader);

                        // Invalid characters are dropped
                        if (val.is_invalid()) {
                           Error::on_invalid_character(state, reader);
                           return;
                        }

                        // non-pass characters are not valid ascii and are mapped to utf8 values
                        if (!val.is_pass()) {
                           result.append(val._value);
                           return;
                        }

                        break;
                     }
                  }
               }

               result.push_back(c); //
            },                 //
            [](String& result, detail::IsStateType auto& state, String&& str) {
               if constexpr (std::is_convertible_v<typename String::value_type, char>) {
                  switch (state.encoding()) {
                     using enum ovdl::detail::Encoding;
                     case Ascii:
                     case Utf8:
                        break;
                     // Skip Ascii and Utf8 encoding
                     default: {
                        auto input = lexy::string_input(str);
                        auto reader = input.reader();
                        using encoding = decltype(reader)::encoding;
                        constexpr auto eof = encoding::eof();

                        if constexpr (requires { result.reserve(str.size()); }) {
                           result.reserve(str.size());
                        }

                        auto begin = reader.position();
                        auto last_it = begin;
                        while (reader.peek() != eof) {
                           // If not within ASCII range
                           if (*reader.position() < 0) {
                              map_value val = try_parse_map(state.encoding(), reader);

                              if (val.is_invalid()) {
                                 Error::on_invalid_character(state, reader);
                                 reader.bump();
                                 continue;
                              } else if (!val.is_pass()) {
                                 result.append(val._value);
                                 last_it = reader.position();
                                 continue;
                              }
                           }

                           while (reader.peek() != eof && *reader.position() > 0) {
                              reader.bump();
                           }
                           result.append(last_it, reader.position());
                           last_it = reader.position();
                        }
                        if (last_it != begin) {
                           return;
                        }
                        break;
                     }
                  }
               }

               result.append(LEXY_MOV(str));                                                                   //
            },                                                                                           //
            []<typename Str = String, typename Iterator>(String& result, detail::IsStateType auto& state, Iterator begin, Iterator end) //
            -> decltype(void(LEXY_DECLVAL(Str).append(begin, end))) {
               if constexpr (std::is_convertible_v<typename String::value_type, char>) {
                  switch (state.encoding()) {
                     using enum ovdl::detail::Encoding;
                     case Ascii:
                     case Utf8:
                        break;
                     // Skip Ascii and Utf8 encoding
                     default: {
                        auto input = lexy::range_input(begin, end);
                        auto reader = input.reader();
                        using encoding = decltype(reader)::encoding;
                        constexpr auto eof = encoding::eof();

                        if constexpr (requires { result.reserve(end - begin); }) {
                           result.reserve(end - begin);
                        }

                        auto begin = reader.position();
                        auto last_it = begin;
                        while (reader.peek() != eof) {
                           // If not within ASCII range
                           if (*reader.position() < 0) {
                              map_value val = try_parse_map(state.encoding(), reader);

                              if (val.is_invalid()) {
                                 Error::on_invalid_character(state, reader);
                                 reader.bump();
                                 continue;
                              } else if (!val.is_pass()) {
                                 result.append(val._value);
                                 last_it = reader.position();
                                 continue;
                              }
                           }

                           while (reader.peek() != eof && *reader.position() > 0) {
                              reader.bump();
                           }
                           result.append(last_it, reader.position());
                           last_it = reader.position();
                        }
                        if (last_it != begin) {
                           return;
                        }
                        break;
                     }
                  }
               }

               result.append(begin, end); //
            },                      //
            []<typename Reader>(String& result, detail::IsStateType auto& state, lexy::lexeme<Reader> lex) {
               using encoding = typename Reader::encoding;
               using _char_type = _string_char_type<String>;
               static_assert(lexy::char_type_compatible_with_reader<Reader, _char_type>,
                  "cannot convert lexeme to this string type");

               if constexpr ((std::same_as<encoding, lexy::default_encoding> || std::same_as<encoding, lexy::byte_encoding>) &&
                          std::convertible_to<typename String::value_type, char>) {
                  auto input = lexy::range_input(lex.begin(), lex.end());
                  auto reader = input.reader();
                  using encoding = decltype(reader)::encoding;
                  constexpr auto eof = encoding::eof();

                  if constexpr (requires { result.reserve(lex.end() - lex.begin()); }) {
                     result.reserve(lex.end() - lex.begin());
                  }

                  auto begin = reader.position();
                  auto last_it = begin;
                  while (reader.peek() != eof) {
                     // If not within ASCII range
                     if (*reader.position() < 0) {
                        map_value val = try_parse_map(state.encoding(), reader);

                        if (val.is_invalid()) {
                           Error::on_invalid_character(state, reader);
                           reader.bump();
                           continue;
                        } else if (!val.is_pass()) {
                           result.append(val._value);
                           last_it = reader.position();
                           continue;
                        }
                     }

                     while (reader.peek() != eof && *reader.position() > 0) {
                        reader.bump();
                     }
                     result.append(last_it, reader.position());
                     last_it = reader.position();
                  }
                  if (last_it != begin) {
                     return;
                  }
               }

               result.append(lex.begin(), lex.end()); //
            }));
}