gchess

-module(pgn).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function]).

-export([pop_move/1, split_movetext/1, remove_tags/1]).

-spec pop_move(binary()) -> gleam@option:option({binary(), binary()}).
pop_move(Pgn) ->
    case gleam@string:pop_grapheme(Pgn) of
        {ok, {Index_first_digit, Rest}} when ((((((((Index_first_digit =:= <<"1"/utf8>>) orelse (Index_first_digit =:= <<"2"/utf8>>)) orelse (Index_first_digit =:= <<"3"/utf8>>)) orelse (Index_first_digit =:= <<"4"/utf8>>)) orelse (Index_first_digit =:= <<"5"/utf8>>)) orelse (Index_first_digit =:= <<"6"/utf8>>)) orelse (Index_first_digit =:= <<"7"/utf8>>)) orelse (Index_first_digit =:= <<"8"/utf8>>)) orelse (Index_first_digit =:= <<"9"/utf8>>) ->
            case gleam@string:split_once(Rest, <<"."/utf8>>) of
                {error, _} ->
                    (erlang:error(#{gleam_error => panic,
                            message => <<"panic expression evaluated"/utf8>>,
                            module => <<"pgn"/utf8>>,
                            function => <<"pop_move"/utf8>>,
                            line => 18}))(<<"Could not parse move index"/utf8>>);

                {ok, {_, Rest@1}} ->
                    Rest@2 = gleam@string:trim(Rest@1),
                    case gleam@string:split_once(Rest@2, <<" "/utf8>>) of
                        {ok, {First_ply, Rest@3}} ->
                            case gleam@string:split_once(Rest@3, <<" "/utf8>>) of
                                {ok, {Second_ply, Rest@4}} ->
                                    case gleam@string:first(Second_ply) of
                                        {ok, <<"1"/utf8>>} ->
                                            {some, {First_ply, <<""/utf8>>}};

                                        {ok, <<"2"/utf8>>} ->
                                            {some, {First_ply, <<""/utf8>>}};

                                        {ok, <<"3"/utf8>>} ->
                                            {some, {First_ply, <<""/utf8>>}};

                                        {ok, <<"4"/utf8>>} ->
                                            {some, {First_ply, <<""/utf8>>}};

                                        {ok, <<"5"/utf8>>} ->
                                            {some, {First_ply, <<""/utf8>>}};

                                        {ok, <<"6"/utf8>>} ->
                                            {some, {First_ply, <<""/utf8>>}};

                                        {ok, <<"7"/utf8>>} ->
                                            {some, {First_ply, <<""/utf8>>}};

                                        {ok, <<"8"/utf8>>} ->
                                            {some, {First_ply, <<""/utf8>>}};

                                        {ok, <<"9"/utf8>>} ->
                                            {some, {First_ply, <<""/utf8>>}};

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

                                        _ ->
                                            {some,
                                                {<<<<First_ply/binary,
                                                            " "/utf8>>/binary,
                                                        Second_ply/binary>>,
                                                    Rest@4}}
                                    end;

                                {error, _} ->
                                    {some,
                                        {<<<<First_ply/binary, " "/utf8>>/binary,
                                                Rest@3/binary>>,
                                            <<""/utf8>>}}
                            end;

                        {error, _} ->
                            {some, {Rest@2, <<""/utf8>>}}
                    end
            end;

        {error, _} ->
            none;

        _ ->
            (erlang:error(#{gleam_error => panic,
                    message => <<"panic expression evaluated"/utf8>>,
                    module => <<"pgn"/utf8>>,
                    function => <<"pop_move"/utf8>>,
                    line => 53}))(<<"could not parse move"/utf8>>)
    end.

-spec split_movetext(binary()) -> list(binary()).
split_movetext(Pgn) ->
    case pop_move(Pgn) of
        {some, {Move, Rest}} ->
            gleam@list:append([Move], split_movetext(Rest));

        none ->
            []
    end.

-spec remove_tags(binary()) -> binary().
remove_tags(Pgn) ->
    case gleam@string:pop_grapheme(Pgn) of
        {ok, {<<"["/utf8>>, Rest}} ->
            case gleam@string:split_once(Rest, <<"]"/utf8>>) of
                {error, _} ->
                    (erlang:error(#{gleam_error => panic,
                            message => <<"panic expression evaluated"/utf8>>,
                            module => <<"pgn"/utf8>>,
                            function => <<"remove_tags"/utf8>>,
                            line => 61}))(<<"Invalid PGN"/utf8>>);

                {ok, {_, Rest@1}} ->
                    remove_tags(Rest@1)
            end;

        _ ->
            Pgn
    end.