-module(hanguleam@composer).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).
-define(FILEPATH, "src/hanguleam/composer.gleam").
-export([combine_vowels/2, combine_character/3, combine_character_unsafe/3, assemble/1]).
-export_type([assemble_error/0]).

-if(?OTP_RELEASE >= 27).
-define(MODULEDOC(Str), -moduledoc(Str)).
-define(DOC(Str), -doc(Str)).
-else.
-define(MODULEDOC(Str), -compile([])).
-define(DOC(Str), -compile([])).
-endif.

-type assemble_error() :: {invalid_choseong, binary()} |
    {invalid_jungseong, binary()} |
    {invalid_jongseong, binary()}.

-file("src/hanguleam/composer.gleam", 27).
?DOC(
    " Combines two Korean vowels into a single complex vowel if possible.\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " combine_vowels(\"ㅗ\", \"ㅏ\")\n"
    " // -> \"ㅘ\"\n"
    "\n"
    " combine_vowels(\"ㅣ\", \"ㅏ\")\n"
    " // -> \"ㅣㅏ\" (no combination possible)\n"
    " ```\n"
).
-spec combine_vowels(binary(), binary()) -> binary().
combine_vowels(Vowel1, Vowel2) ->
    hanguleam@internal@unicode:assemble_vowel_string(
        <<Vowel1/binary, Vowel2/binary>>
    ).

-file("src/hanguleam/composer.gleam", 101).
-spec do_combine(binary(), binary(), binary()) -> binary().
do_combine(Choseong, Jungseong, Jongseong) ->
    Result = begin
        gleam@result:'try'(
            hanguleam@internal@utils:find_index(
                [<<"ㄱ"/utf8>>,
                    <<"ㄲ"/utf8>>,
                    <<"ㄴ"/utf8>>,
                    <<"ㄷ"/utf8>>,
                    <<"ㄸ"/utf8>>,
                    <<"ㄹ"/utf8>>,
                    <<"ㅁ"/utf8>>,
                    <<"ㅂ"/utf8>>,
                    <<"ㅃ"/utf8>>,
                    <<"ㅅ"/utf8>>,
                    <<"ㅆ"/utf8>>,
                    <<"ㅇ"/utf8>>,
                    <<"ㅈ"/utf8>>,
                    <<"ㅉ"/utf8>>,
                    <<"ㅊ"/utf8>>,
                    <<"ㅋ"/utf8>>,
                    <<"ㅌ"/utf8>>,
                    <<"ㅍ"/utf8>>,
                    <<"ㅎ"/utf8>>],
                Choseong
            ),
            fun(Choseong_idx) ->
                gleam@result:'try'(
                    hanguleam@internal@utils:find_index(
                        [<<"ㅏ"/utf8>>,
                            <<"ㅐ"/utf8>>,
                            <<"ㅑ"/utf8>>,
                            <<"ㅒ"/utf8>>,
                            <<"ㅓ"/utf8>>,
                            <<"ㅔ"/utf8>>,
                            <<"ㅕ"/utf8>>,
                            <<"ㅖ"/utf8>>,
                            <<"ㅗ"/utf8>>,
                            <<"ㅘ"/utf8>>,
                            <<"ㅙ"/utf8>>,
                            <<"ㅚ"/utf8>>,
                            <<"ㅛ"/utf8>>,
                            <<"ㅜ"/utf8>>,
                            <<"ㅝ"/utf8>>,
                            <<"ㅞ"/utf8>>,
                            <<"ㅟ"/utf8>>,
                            <<"ㅠ"/utf8>>,
                            <<"ㅡ"/utf8>>,
                            <<"ㅢ"/utf8>>,
                            <<"ㅣ"/utf8>>],
                        Jungseong
                    ),
                    fun(Jungseong_idx) ->
                        gleam@result:'try'(
                            hanguleam@internal@utils:find_index(
                                [<<""/utf8>>,
                                    <<"ㄱ"/utf8>>,
                                    <<"ㄲ"/utf8>>,
                                    <<"ㄳ"/utf8>>,
                                    <<"ㄴ"/utf8>>,
                                    <<"ㄵ"/utf8>>,
                                    <<"ㄶ"/utf8>>,
                                    <<"ㄷ"/utf8>>,
                                    <<"ㄹ"/utf8>>,
                                    <<"ㄺ"/utf8>>,
                                    <<"ㄻ"/utf8>>,
                                    <<"ㄼ"/utf8>>,
                                    <<"ㄽ"/utf8>>,
                                    <<"ㄾ"/utf8>>,
                                    <<"ㄿ"/utf8>>,
                                    <<"ㅀ"/utf8>>,
                                    <<"ㅁ"/utf8>>,
                                    <<"ㅂ"/utf8>>,
                                    <<"ㅄ"/utf8>>,
                                    <<"ㅅ"/utf8>>,
                                    <<"ㅆ"/utf8>>,
                                    <<"ㅇ"/utf8>>,
                                    <<"ㅈ"/utf8>>,
                                    <<"ㅊ"/utf8>>,
                                    <<"ㅋ"/utf8>>,
                                    <<"ㅌ"/utf8>>,
                                    <<"ㅍ"/utf8>>,
                                    <<"ㅎ"/utf8>>],
                                Jongseong
                            ),
                            fun(Jongseong_idx) ->
                                {ok,
                                    {Choseong_idx, Jungseong_idx, Jongseong_idx}}
                            end
                        )
                    end
                )
            end
        )
    end,
    case Result of
        {ok, {Cho, Jung, Jong}} ->
            Codepoint_int = ((16#AC00 + ((Cho * 21) * 28)) + (Jung * 28)) + Jong,
            case gleam@string:utf_codepoint(Codepoint_int) of
                {ok, Codepoint} ->
                    gleam_stdlib:utf_codepoint_list_to_string([Codepoint]);

                {error, _} ->
                    <<""/utf8>>
            end;

        {error, _} ->
            <<""/utf8>>
    end.

-file("src/hanguleam/composer.gleam", 81).
?DOC(
    " Combines Korean jamo components into a complete Hangul syllable.\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " combine_character(choseong: \"ㄱ\", jungseong: \"ㅏ\", jongseong: \"\")\n"
    " // -> Ok(\"가\")\n"
    "\n"
    " combine_character(choseong: \"ㄲ\", jungseong: \"ㅠ\", jongseong: \"ㅇ\")\n"
    " // -> Ok(\"뀽\")\n"
    " ```\n"
).
-spec combine_character(binary(), binary(), binary()) -> {ok, binary()} |
    {error, assemble_error()}.
combine_character(Choseong, Jungseong, Jongseong) ->
    Jungseong@1 = hanguleam@internal@unicode:assemble_vowel_string(Jungseong),
    Jongseong@1 = hanguleam@internal@unicode:assemble_consonant_string(
        Jongseong
    ),
    case {hanguleam@validator:can_be_choseong(Choseong),
        hanguleam@validator:can_be_jungseong(Jungseong@1),
        hanguleam@validator:can_be_jongseong(Jongseong@1)} of
        {true, true, true} ->
            {ok, do_combine(Choseong, Jungseong@1, Jongseong@1)};

        {false, _, _} ->
            {error, {invalid_choseong, Choseong}};

        {_, false, _} ->
            {error, {invalid_jungseong, Jungseong@1}};

        {_, _, false} ->
            {error, {invalid_jongseong, Jongseong@1}}
    end.

-file("src/hanguleam/composer.gleam", 39).
?DOC(
    " ⚠️ **UNSAFE**: Combines jamo into Hangul syllable without validation. **WILL PANIC** on invalid inputs.\n"
    " Use `combine_character()` for safe operation or ensure inputs are pre-validated.\n"
).
-spec combine_character_unsafe(binary(), binary(), binary()) -> binary().
combine_character_unsafe(Choseong, Jungseong, Jongseong) ->
    case combine_character(Choseong, Jungseong, Jongseong) of
        {ok, Combined} ->
            Combined;

        {error, {invalid_choseong, Invalid}} ->
            Msg = <<<<"Internal error: invalid choseong '"/utf8,
                    Invalid/binary>>/binary,
                "' from validated syllable"/utf8>>,
            erlang:error(#{gleam_error => panic,
                    message => Msg,
                    file => <<?FILEPATH/utf8>>,
                    module => <<"hanguleam/composer"/utf8>>,
                    function => <<"combine_character_unsafe"/utf8>>,
                    line => 51});

        {error, {invalid_jungseong, Invalid@1}} ->
            Msg@1 = <<<<"Internal error: invalid jungseong '"/utf8,
                    Invalid@1/binary>>/binary,
                "' from validated syllable"/utf8>>,
            erlang:error(#{gleam_error => panic,
                    message => Msg@1,
                    file => <<?FILEPATH/utf8>>,
                    module => <<"hanguleam/composer"/utf8>>,
                    function => <<"combine_character_unsafe"/utf8>>,
                    line => 58});

        {error, {invalid_jongseong, Invalid@2}} ->
            Msg@2 = <<<<"Internal error: invalid jongseong '"/utf8,
                    Invalid@2/binary>>/binary,
                "' from validated syllable"/utf8>>,
            erlang:error(#{gleam_error => panic,
                    message => Msg@2,
                    file => <<?FILEPATH/utf8>>,
                    module => <<"hanguleam/composer"/utf8>>,
                    function => <<"combine_character_unsafe"/utf8>>,
                    line => 65})
    end.

-file("src/hanguleam/composer.gleam", 225).
-spec extend_syllable_without_batchim(
    binary(),
    binary(),
    hanguleam@types:jamo()
) -> binary().
extend_syllable_without_batchim(Cho, Jung, Jamo) ->
    case Jamo of
        {consonant, Consonant} ->
            case hanguleam@validator:can_be_jongseong(Consonant) of
                true ->
                    combine_character_unsafe(Cho, Jung, Consonant);

                false ->
                    <<(combine_character_unsafe(Cho, Jung, <<""/utf8>>))/binary,
                        Consonant/binary>>
            end;

        {vowel, Vowel} ->
            Extended_vowel = <<Jung/binary, Vowel/binary>>,
            case hanguleam@validator:can_be_jungseong(Extended_vowel) of
                true ->
                    combine_character_unsafe(Cho, Extended_vowel, <<""/utf8>>);

                false ->
                    <<(combine_character_unsafe(Cho, Jung, <<""/utf8>>))/binary,
                        Vowel/binary>>
            end
    end.

-file("src/hanguleam/composer.gleam", 246).
-spec extend_syllable_with_batchim(
    binary(),
    binary(),
    binary(),
    hanguleam@types:jamo()
) -> binary().
extend_syllable_with_batchim(Cho, Jung, Jong, Jamo) ->
    case Jamo of
        {vowel, Vowel} ->
            case hanguleam@validator:can_be_choseong(Jong) of
                true ->
                    <<(combine_character_unsafe(Cho, Jung, <<""/utf8>>))/binary,
                        (combine_character_unsafe(Jong, Vowel, <<""/utf8>>))/binary>>;

                false ->
                    <<(combine_character_unsafe(Cho, Jung, Jong))/binary,
                        Vowel/binary>>
            end;

        {consonant, Consonant} ->
            Complex_batchim = <<Jong/binary, Consonant/binary>>,
            case hanguleam@validator:can_be_jongseong(Complex_batchim) of
                true ->
                    combine_character_unsafe(Cho, Jung, Complex_batchim);

                false ->
                    <<(combine_character_unsafe(Cho, Jung, Jong))/binary,
                        Consonant/binary>>
            end
    end.

-file("src/hanguleam/composer.gleam", 270).
-spec extend_complex_batchim_syllable(
    binary(),
    binary(),
    binary(),
    hanguleam@types:jamo()
) -> binary().
extend_complex_batchim_syllable(Cho, Jung, Jong, Jamo) ->
    case Jamo of
        {vowel, Vowel} ->
            Leading_consonant = gleam@string:slice(Jong, 0, 1),
            Tailing_consonant = gleam@string:slice(Jong, 1, 1),
            case hanguleam@validator:can_be_choseong(Tailing_consonant) of
                true ->
                    <<(combine_character_unsafe(Cho, Jung, Leading_consonant))/binary,
                        (combine_character_unsafe(
                            Tailing_consonant,
                            Vowel,
                            <<""/utf8>>
                        ))/binary>>;

                false ->
                    <<(combine_character_unsafe(Cho, Jung, Jong))/binary,
                        Vowel/binary>>
            end;

        {consonant, Consonant} ->
            <<(combine_character_unsafe(Cho, Jung, Jong))/binary,
                Consonant/binary>>
    end.

-file("src/hanguleam/composer.gleam", 186).
-spec try_extend_syllable(
    hanguleam@types:hangul_syllable(),
    hanguleam@types:jamo()
) -> binary().
try_extend_syllable(Syllable, Jamo) ->
    Parsed = hanguleam@internal@character:parse_hangul_syllable(Syllable),
    case Parsed of
        {simple_c_v, {choseong, Cho}, {jungseong, Jung}} ->
            extend_syllable_without_batchim(Cho, Jung, Jamo);

        {compound_c_v, {choseong, Cho@1}, {jungseong, Jung@1}} ->
            extend_syllable_without_batchim(Cho@1, Jung@1, Jamo);

        {simple_c_v_c,
            {choseong, Cho@2},
            {jungseong, Jung@2},
            {jongseong, Jong}} ->
            extend_syllable_with_batchim(Cho@2, Jung@2, Jong, Jamo);

        {compound_c_v_c,
            {choseong, Cho@3},
            {jungseong, Jung@3},
            {jongseong, Jong@1}} ->
            extend_syllable_with_batchim(Cho@3, Jung@3, Jong@1, Jamo);

        {complex_batchim,
            {choseong, Cho@4},
            {jungseong, Jung@4},
            {jongseong, Jong@2}} ->
            extend_complex_batchim_syllable(Cho@4, Jung@4, Jong@2, Jamo);

        {compound_complex_batchim,
            {choseong, Cho@5},
            {jungseong, Jung@5},
            {jongseong, Jong@3}} ->
            extend_syllable_with_batchim(Cho@5, Jung@5, Jong@3, Jamo)
    end.

-file("src/hanguleam/composer.gleam", 292).
-spec try_combine_jamos(hanguleam@types:jamo(), hanguleam@types:jamo()) -> binary().
try_combine_jamos(Last, First) ->
    case {Last, First} of
        {{consonant, Consonant}, {vowel, Vowel}} ->
            case hanguleam@validator:can_be_choseong(Consonant) of
                true ->
                    combine_character_unsafe(Consonant, Vowel, <<""/utf8>>);

                false ->
                    <<Consonant/binary, Vowel/binary>>
            end;

        {{vowel, V1}, {vowel, V2}} ->
            Combined = combine_vowels(V1, V2),
            case string:length(Combined) =:= 1 of
                true ->
                    Combined;

                false ->
                    <<V1/binary, V2/binary>>
            end;

        {{vowel, V1@1}, {consonant, C1}} ->
            <<V1@1/binary, C1/binary>>;

        {{consonant, C1@1}, {consonant, C2}} ->
            <<C1@1/binary, C2/binary>>
    end.

-file("src/hanguleam/composer.gleam", 312).
-spec get_char_type_at(
    binary(),
    fun((binary()) -> {ok, binary()} | {error, nil})
) -> hanguleam@types:character_type().
get_char_type_at(Text, Position) ->
    _pipe = Text,
    _pipe@1 = Position(_pipe),
    _pipe@2 = gleam@result:map(
        _pipe@1,
        fun hanguleam@internal@character:get_character_type/1
    ),
    gleam@result:unwrap(_pipe@2, empty).

-file("src/hanguleam/composer.gleam", 152).
-spec merge_fragments({binary(), hanguleam@types:character_type()}, binary()) -> {binary(),
    hanguleam@types:character_type()}.
merge_fragments(Acc, Fragment) ->
    {Accumulated, Last_state} = Acc,
    Next_char_type = get_char_type_at(Fragment, fun gleam@string:first/1),
    case {Last_state, Next_char_type} of
        {{incomplete_hangul, Last_jamo}, {incomplete_hangul, First_jamo}} ->
            Combined = try_combine_jamos(Last_jamo, First_jamo),
            New_text = <<<<(gleam@string:drop_end(Accumulated, 1))/binary,
                    Combined/binary>>/binary,
                (gleam@string:drop_start(Fragment, 1))/binary>>,
            New_state = get_char_type_at(New_text, fun gleam@string:last/1),
            {New_text, New_state};

        {{complete_hangul, Syllable}, {incomplete_hangul, Jamo}} ->
            Extended = try_extend_syllable(Syllable, Jamo),
            New_text@1 = <<(gleam@string:drop_end(Accumulated, 1))/binary,
                Extended/binary>>,
            New_state@1 = get_char_type_at(Extended, fun gleam@string:last/1),
            {New_text@1, New_state@1};

        {_, _} ->
            New_text@2 = <<Accumulated/binary, Fragment/binary>>,
            New_state@2 = get_char_type_at(New_text@2, fun gleam@string:last/1),
            {New_text@2, New_state@2}
    end.

-file("src/hanguleam/composer.gleam", 146).
?DOC(
    " Assembles Korean text fragments by intelligently combining characters.\n"
    " Processes fragments according to Korean linguistic rules including \n"
    " consonant-vowel combinations and Korean linking (연음).\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " assemble([\"ㄱ\", \"ㅏ\", \"ㅂ\"])\n"
    " // -> \"갑\"\n"
    "\n"
    " assemble([\"안녕하\", \"ㅅ\", \"ㅔ\", \"요\"])\n"
    " // -> \"안녕하세요\"\n"
    "\n"
    " assemble([\"뀽\", \"ㅏ\"])\n"
    " // -> \"뀨아\"\n"
    " ```\n"
).
-spec assemble(list(binary())) -> binary().
assemble(Fragments) ->
    _pipe = Fragments,
    _pipe@1 = gleam@list:fold(
        _pipe,
        {<<""/utf8>>, empty},
        fun merge_fragments/2
    ),
    gleam@pair:first(_pipe@1).