gleam_bson

-module(bson@object_id).
-compile(no_auto_import).

-export([to_bit_string/1, to_string/1, from_string/1, from_bit_string/1]).
-export_type([object_id/0]).

-opaque object_id() :: {object_id, bitstring()}.

-spec to_bit_string(object_id()) -> bitstring().
to_bit_string(Id) ->
    case Id of
        {object_id, Value} ->
            Value
    end.

-spec to_string(object_id()) -> binary().
to_string(Id) ->
    case Id of
        {object_id, Value} ->
            _pipe = Value,
            to_string_internal(_pipe, <<""/utf8>>)
    end.

-spec from_string(binary()) -> {ok, object_id()} | {error, nil}.
from_string(Id) ->
    case begin
        _pipe = Id,
        gleam@string:length(_pipe)
    end
    =:= 24 of
        true ->
            Codes = begin
                _pipe@1 = Id,
                _pipe@2 = gleam@string:to_graphemes(_pipe@1),
                _pipe@4 = gleam@list:map(
                    _pipe@2,
                    fun(Char) ->
                        <<Code>> = begin
                            _pipe@3 = Char,
                            gleam@bit_string:from_string(_pipe@3)
                        end,
                        Code
                    end
                ),
                gleam@list:map(
                    _pipe@4,
                    fun(Code@1) ->
                        _pipe@5 = Code@1,
                        to_digit(_pipe@5)
                    end
                )
            end,
            case begin
                _pipe@6 = Codes,
                gleam@list:any(
                    _pipe@6,
                    fun(Item) -> gleam@result:is_error(Item) end
                )
            end of
                false ->
                    Value = begin
                        _pipe@7 = Codes,
                        _pipe@8 = gleam@list:map(
                            _pipe@7,
                            fun(Item@1) ->
                                {ok, Digit@1} = case Item@1 of
                                    {ok, Digit} -> {ok, Digit};
                                    _try ->
                                        erlang:error(#{gleam_error => assert,
                                                       message => <<"Assertion pattern match failed"/utf8>>,
                                                       value => _try,
                                                       module => <<"bson/object_id"/utf8>>,
                                                       function => <<"from_string"/utf8>>,
                                                       line => 48})
                                end,
                                Digit@1
                            end
                        ),
                        _pipe@9 = gleam@list:sized_chunk(_pipe@8, 2),
                        _pipe@10 = gleam@list:map(
                            _pipe@9,
                            fun(Pair) ->
                                [A, B] = Pair,
                                <<A:4, B:4>>
                            end
                        ),
                        gleam@bit_string:concat(_pipe@10)
                    end,
                    {ok, {object_id, Value}};

                true ->
                    {error, nil}
            end;

        false ->
            {error, nil}
    end.

-spec from_bit_string(bitstring()) -> {ok, object_id()} | {error, nil}.
from_bit_string(Id) ->
    case gleam@bit_string:byte_size(Id) =:= 12 of
        true ->
            {ok, {object_id, Id}};

        false ->
            {error, nil}
    end.

-spec to_string_internal(bitstring(), binary()) -> binary().
to_string_internal(Remaining, Storage) ->
    <<Low:4, High:4, Remaining@1/binary>> = Remaining,
    New_storage = begin
        _pipe = Storage,
        _pipe@1 = gleam@string:append(_pipe, to_char(Low)),
        gleam@string:append(_pipe@1, to_char(High))
    end,
    case gleam@bit_string:byte_size(Remaining@1) =:= 0 of
        true ->
            New_storage;

        false ->
            to_string_internal(Remaining@1, New_storage)
    end.

-spec to_digit(integer()) -> {ok, integer()} | {error, nil}.
to_digit(Char) ->
    case (Char >= 48) andalso (Char =< 57) of
        true ->
            {ok, Char - 48};

        false ->
            case (Char >= 65) andalso (Char =< 70) of
                true ->
                    {ok, Char - 55};

                false ->
                    case (Char >= 97) andalso (Char =< 102) of
                        true ->
                            {ok, Char - 87};

                        false ->
                            {error, nil}
                    end
            end
    end.

-spec to_char(integer()) -> binary().
to_char(Digit) ->
    Ch = case Digit < 10 of
        true ->
            Digit + 48;

        false ->
            Digit + 87
    end,
    {ok, Digit@2} = case gleam@bit_string:to_string(<<Ch>>) of
        {ok, Digit@1} -> {ok, Digit@1};
        _try ->
            erlang:error(#{gleam_error => assert,
                           message => <<"Assertion pattern match failed"/utf8>>,
                           value => _try,
                           module => <<"bson/object_id"/utf8>>,
                           function => <<"to_char"/utf8>>,
                           line => 107})
    end,
    Digit@2.