distribute

-module(distribute@codec@tagged).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/distribute/codec/tagged.gleam").
-export([new/3, payload/1, tag/1, version/1, sized_decoder/3, decoder/3, codec/3, encoder/1, encode_tagged/4, decode_tagged/4]).
-export_type([tagged_message/1]).

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

-opaque tagged_message(IWQ) :: {tagged_message, binary(), integer(), IWQ}.

-file("src/distribute/codec/tagged.gleam", 20).
?DOC(" Create a tagged message.\n").
-spec new(binary(), integer(), IWR) -> tagged_message(IWR).
new(Tag, Version, Payload) ->
    {tagged_message, Tag, Version, Payload}.

-file("src/distribute/codec/tagged.gleam", 29).
?DOC(" Extract the payload.\n").
-spec payload(tagged_message(IWT)) -> IWT.
payload(Msg) ->
    erlang:element(4, Msg).

-file("src/distribute/codec/tagged.gleam", 34).
?DOC(" Get the tag.\n").
-spec tag(tagged_message(any())) -> binary().
tag(Msg) ->
    erlang:element(2, Msg).

-file("src/distribute/codec/tagged.gleam", 39).
?DOC(" Get the version.\n").
-spec version(tagged_message(any())) -> integer().
version(Msg) ->
    erlang:element(3, Msg).

-file("src/distribute/codec/tagged.gleam", 134).
?DOC(
    " Parse and validate the `[tag_len:32][tag][version:32]` header shared by\n"
    " `decoder` and `sized_decoder`. Returns the verified tag, version, and\n"
    " the payload bytes that follow the header.\n"
).
-spec parse_header(bitstring(), binary(), integer()) -> {ok,
        {binary(), integer(), bitstring()}} |
    {error, distribute@codec:decode_error()}.
parse_header(Binary, Expected_tag, Expected_version) ->
    case Binary of
        <<Tag_len:32, Rest/bitstring>> ->
            gleam@result:'try'(
                begin
                    _pipe = gleam_stdlib:bit_array_slice(Rest, 0, Tag_len),
                    gleam@result:replace_error(
                        _pipe,
                        {insufficient_data, <<"tag truncated"/utf8>>}
                    )
                end,
                fun(Tag_bytes) ->
                    gleam@result:'try'(
                        begin
                            _pipe@1 = gleam@bit_array:to_string(Tag_bytes),
                            gleam@result:replace_error(
                                _pipe@1,
                                {invalid_binary, <<"tag not valid UTF-8"/utf8>>}
                            )
                        end,
                        fun(Tag_string) -> case Tag_string =:= Expected_tag of
                                false ->
                                    {error,
                                        {tag_mismatch, Expected_tag, Tag_string}};

                                true ->
                                    gleam@result:'try'(
                                        begin
                                            _pipe@2 = gleam_stdlib:bit_array_slice(
                                                Rest,
                                                Tag_len,
                                                erlang:byte_size(Rest) - Tag_len
                                            ),
                                            gleam@result:replace_error(
                                                _pipe@2,
                                                {insufficient_data,
                                                    <<"missing version"/utf8>>}
                                            )
                                        end,
                                        fun(After_tag) -> case After_tag of
                                                <<Ver:32,
                                                    Payload_rest/bitstring>> ->
                                                    case Ver =:= Expected_version of
                                                        false ->
                                                            {error,
                                                                {version_mismatch,
                                                                    Expected_version,
                                                                    Ver}};

                                                        true ->
                                                            {ok,
                                                                {Tag_string,
                                                                    Ver,
                                                                    Payload_rest}}
                                                    end;

                                                _ ->
                                                    {error,
                                                        {insufficient_data,
                                                            <<"missing version or payload"/utf8>>}}
                                            end end
                                    )
                            end end
                    )
                end
            );

        _ ->
            {error, {invalid_binary, <<"missing tag length"/utf8>>}}
    end.

-file("src/distribute/codec/tagged.gleam", 95).
?DOC(
    " Sized decoder for tagged messages with tag and version validation.\n"
    "\n"
    " Returns `TagMismatch` or `VersionMismatch` errors for protocol mismatches.\n"
    " Unlike `decoder`, returns remaining bytes for use in composite codecs.\n"
).
-spec sized_decoder(
    binary(),
    integer(),
    fun((bitstring()) -> {ok, {IXD, bitstring()}} |
        {error, distribute@codec:decode_error()})
) -> fun((bitstring()) -> {ok, {tagged_message(IXD), bitstring()}} |
    {error, distribute@codec:decode_error()}).
sized_decoder(Expected_tag, Expected_version, Payload_sized_decoder) ->
    fun(Binary) ->
        gleam@result:'try'(
            parse_header(Binary, Expected_tag, Expected_version),
            fun(_use0) ->
                {Tag_string, Ver, Payload_rest} = _use0,
                gleam@result:'try'(
                    Payload_sized_decoder(Payload_rest),
                    fun(_use0@1) ->
                        {Payload, Remaining} = _use0@1,
                        {ok,
                            {{tagged_message, Tag_string, Ver, Payload},
                                Remaining}}
                    end
                )
            end
        )
    end.

-file("src/distribute/codec/tagged.gleam", 115).
?DOC(
    " Decoder for tagged messages with tag and version validation.\n"
    "\n"
    " Unlike `sized_decoder`, the payload decoder receives every byte after\n"
    " the header and is responsible for its own trailing-byte policy.\n"
).
-spec decoder(
    binary(),
    integer(),
    fun((bitstring()) -> {ok, IXH} | {error, distribute@codec:decode_error()})
) -> fun((bitstring()) -> {ok, tagged_message(IXH)} |
    {error, distribute@codec:decode_error()}).
decoder(Expected_tag, Expected_version, Payload_decoder) ->
    fun(Binary) ->
        gleam@result:'try'(
            parse_header(Binary, Expected_tag, Expected_version),
            fun(_use0) ->
                {Tag_string, Ver, Payload_rest} = _use0,
                gleam@result:'try'(
                    distribute@codec:decode(Payload_decoder, Payload_rest),
                    fun(Payload) ->
                        {ok, {tagged_message, Tag_string, Ver, Payload}}
                    end
                )
            end
        )
    end.

-file("src/distribute/codec/tagged.gleam", 181).
?DOC(
    " Bundled `Codec` for tagged messages.\n"
    "\n"
    " ```gleam\n"
    " let tagged_int = tagged.codec(\"counter\", 1, codec.int())\n"
    " ```\n"
).
-spec codec(binary(), integer(), distribute@codec:codec(IXN)) -> distribute@codec:codec(tagged_message(IXN)).
codec(Expected_tag, Expected_version, Payload_codec) ->
    {codec,
        encoder(erlang:element(2, Payload_codec)),
        decoder(
            Expected_tag,
            Expected_version,
            erlang:element(3, Payload_codec)
        ),
        sized_decoder(
            Expected_tag,
            Expected_version,
            erlang:element(4, Payload_codec)
        )}.

-file("src/distribute/codec/tagged.gleam", 52).
?DOC(
    " Encoder for tagged messages.\n"
    "\n"
    " Format: `[tag_len:32][tag:utf8][version:32][payload]`\n"
    "\n"
    " Rejects values that would silently wrap when written to the fixed-width\n"
    " 32-bit fields:\n"
    " - `version` must be in `[0, 2^32 - 1]`\n"
    " - `tag` byte-length must be in `[0, 2^32 - 1]` (a 4 GiB tag is absurd\n"
    "   in practice but the bound is enforced for defence in depth)\n"
).
-spec encoder(
    fun((IWZ) -> {ok, bitstring()} | {error, distribute@codec:encode_error()})
) -> fun((tagged_message(IWZ)) -> {ok, bitstring()} |
    {error, distribute@codec:encode_error()}).
encoder(Payload_encoder) ->
    fun(Msg) ->
        case (erlang:element(3, Msg) < 0) orelse (erlang:element(3, Msg) > 4294967295) of
            true ->
                {error,
                    {value_too_large,
                        <<<<"tagged version "/utf8,
                                (erlang:integer_to_binary(
                                    erlang:element(3, Msg)
                                ))/binary>>/binary,
                            " out of unsigned 32-bit range"/utf8>>}};

            false ->
                Tag_bytes = gleam_stdlib:identity(erlang:element(2, Msg)),
                Tag_len = erlang:byte_size(Tag_bytes),
                case Tag_len > 4294967295 of
                    true ->
                        {error,
                            {value_too_large,
                                <<<<"tagged tag length "/utf8,
                                        (erlang:integer_to_binary(Tag_len))/binary>>/binary,
                                    " exceeds unsigned 32-bit range"/utf8>>}};

                    false ->
                        gleam@result:'try'(
                            distribute@codec:encode(
                                Payload_encoder,
                                erlang:element(4, Msg)
                            ),
                            fun(Payload_bytes) ->
                                {ok,
                                    <<Tag_len:32,
                                        Tag_bytes/bitstring,
                                        (erlang:element(3, Msg)):32,
                                        Payload_bytes/bitstring>>}
                            end
                        )
                end
        end
    end.

-file("src/distribute/codec/tagged.gleam", 198).
?DOC(" Convenience: encode a value as a tagged message in one step.\n").
-spec encode_tagged(
    binary(),
    integer(),
    fun((IXR) -> {ok, bitstring()} | {error, distribute@codec:encode_error()}),
    IXR
) -> {ok, bitstring()} | {error, distribute@codec:encode_error()}.
encode_tagged(Tag, Version, Payload_encoder, Value) ->
    Msg = new(Tag, Version, Value),
    distribute@codec:encode(encoder(Payload_encoder), Msg).

-file("src/distribute/codec/tagged.gleam", 209).
?DOC(" Convenience: decode binary as a tagged message and extract the payload.\n").
-spec decode_tagged(
    binary(),
    integer(),
    fun((bitstring()) -> {ok, IXV} | {error, distribute@codec:decode_error()}),
    bitstring()
) -> {ok, IXV} | {error, distribute@codec:decode_error()}.
decode_tagged(Expected_tag, Expected_version, Payload_decoder, Data) ->
    gleam@result:'try'(
        distribute@codec:decode(
            decoder(Expected_tag, Expected_version, Payload_decoder),
            Data
        ),
        fun(Msg) -> {ok, payload(Msg)} end
    ).