multipartkit

-module(multipartkit@internal@bytes).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/multipartkit/internal/bytes.gleam").
-export([find_index/3, slice_or_empty/3, drop/2, find_blank_line/2, equals_ascii_ci/2]).

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

?MODULEDOC(false).

-file("src/multipartkit/internal/bytes.gleam", 29).
?DOC(false).
-spec find_index_loop(bitstring(), bitstring(), integer(), integer(), integer()) -> {ok,
        integer()} |
    {error, nil}.
find_index_loop(Haystack, Needle, From, Needle_len, Haystack_len) ->
    case (From + Needle_len) > Haystack_len of
        true ->
            {error, nil};

        false ->
            case gleam_stdlib:bit_array_slice(Haystack, From, Needle_len) of
                {ok, Window} ->
                    case Window =:= Needle of
                        true ->
                            {ok, From};

                        false ->
                            find_index_loop(
                                Haystack,
                                Needle,
                                From + 1,
                                Needle_len,
                                Haystack_len
                            )
                    end;

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

-file("src/multipartkit/internal/bytes.gleam", 16).
?DOC(false).
-spec find_index(bitstring(), bitstring(), integer()) -> {ok, integer()} |
    {error, nil}.
find_index(Haystack, Needle, From) ->
    Needle_len = erlang:byte_size(Needle),
    Haystack_len = erlang:byte_size(Haystack),
    case Needle_len of
        0 ->
            {ok, From};

        _ ->
            find_index_loop(Haystack, Needle, From, Needle_len, Haystack_len)
    end.

-file("src/multipartkit/internal/bytes.gleam", 60).
?DOC(false).
-spec slice_or_empty(bitstring(), integer(), integer()) -> bitstring().
slice_or_empty(Buf, At, Length) ->
    gleam@result:unwrap(gleam_stdlib:bit_array_slice(Buf, At, Length), <<>>).

-file("src/multipartkit/internal/bytes.gleam", 65).
?DOC(false).
-spec drop(bitstring(), integer()) -> bitstring().
drop(Buf, From) ->
    Total = erlang:byte_size(Buf),
    case From >= Total of
        true ->
            <<>>;

        false ->
            slice_or_empty(Buf, From, Total - From)
    end.

-file("src/multipartkit/internal/bytes.gleam", 118).
?DOC(false).
-spec next_line_offset(bitstring(), integer(), integer()) -> {ok, integer()} |
    {error, nil}.
next_line_offset(Buf, From, Total) ->
    case From >= Total of
        true ->
            {error, nil};

        false ->
            case gleam_stdlib:bit_array_slice(Buf, From, 2) of
                {ok, <<"\r\n"/utf8>>} ->
                    {ok, From + 2};

                {ok, <<10, _>>} ->
                    {ok, From + 1};

                _ ->
                    case gleam_stdlib:bit_array_slice(Buf, From, 1) of
                        {ok, <<10>>} ->
                            {ok, From + 1};

                        _ ->
                            next_line_offset(Buf, From + 1, Total)
                    end
            end
    end.

-file("src/multipartkit/internal/bytes.gleam", 94).
?DOC(false).
-spec find_blank_line_loop(bitstring(), integer(), integer()) -> {ok,
        {integer(), integer()}} |
    {error, nil}.
find_blank_line_loop(Buf, At, Total) ->
    case At >= Total of
        true ->
            {error, nil};

        false ->
            case gleam_stdlib:bit_array_slice(Buf, At, 2) of
                {ok, <<"\r\n"/utf8>>} ->
                    {ok, {At, At + 2}};

                {ok, <<10, _>>} ->
                    {ok, {At, At + 1}};

                _ ->
                    case gleam_stdlib:bit_array_slice(Buf, At, 1) of
                        {ok, <<10>>} ->
                            {ok, {At, At + 1}};

                        _ ->
                            case next_line_offset(Buf, At, Total) of
                                {error, _} ->
                                    {error, nil};

                                {ok, Next} ->
                                    find_blank_line_loop(Buf, Next, Total)
                            end
                    end
            end
    end.

-file("src/multipartkit/internal/bytes.gleam", 89).
?DOC(false).
-spec find_blank_line(bitstring(), integer()) -> {ok, {integer(), integer()}} |
    {error, nil}.
find_blank_line(Buf, From) ->
    Total = erlang:byte_size(Buf),
    find_blank_line_loop(Buf, From, Total).

-file("src/multipartkit/internal/bytes.gleam", 148).
?DOC(false).
-spec fold_ascii(integer()) -> integer().
fold_ascii(Byte) ->
    case (Byte >= 16#41) andalso (Byte =< 16#5A) of
        true ->
            Byte + 32;

        false ->
            Byte
    end.

-file("src/multipartkit/internal/bytes.gleam", 136).
?DOC(false).
-spec equals_ascii_ci(bitstring(), bitstring()) -> boolean().
equals_ascii_ci(A, B) ->
    case {A, B} of
        {<<>>, <<>>} ->
            true;

        {<<X, Ax/binary>>, <<Y, By/binary>>} ->
            case fold_ascii(X) =:= fold_ascii(Y) of
                true ->
                    equals_ascii_ci(Ax, By);

                false ->
                    false
            end;

        {_, _} ->
            false
    end.