ywt_core

-module(ywt@internal@core).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/ywt/internal/core.gleam").
-export([bits_decoder/0, int_decoder/0, bits_to_json/1, int_to_json/1, rsa_modulus_is_large_enough/1, bits_of_length_decoder/1, curve_decoder/0, named_curve/1, named_curve_size/1, rsa_padding/1, digest_type/1, digest_size/1]).
-export_type([error/0, named_curve/0, padding/0, digest_type/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.

?MODULEDOC(false).

-type error() :: malformed_token |
    invalid_header_encoding |
    invalid_payload_encoding |
    invalid_signature_encoding |
    {invalid_header_json, gleam@json:decode_error()} |
    {header_decoding_error, list(gleam@dynamic@decode:decode_error())} |
    unsupported_critical_header |
    unsupported_unencoded_payload |
    {invalid_payload_json, gleam@json:decode_error()} |
    no_matching_key |
    invalid_signature |
    {token_expired, gleam@time@timestamp:timestamp()} |
    {token_not_yet_valid, gleam@time@timestamp:timestamp()} |
    {invalid_issuer, list(binary()), binary()} |
    {invalid_audience, list(binary()), list(binary())} |
    {invalid_type, binary(), binary()} |
    {invalid_subject, list(binary()), binary()} |
    {invalid_id, list(binary()), binary()} |
    {missing_claim, binary()} |
    {claim_decoding_error, binary(), list(gleam@dynamic@decode:decode_error())} |
    {invalid_custom_claim, binary()} |
    {payload_decoding_error, list(gleam@dynamic@decode:decode_error())}.

-type named_curve() :: secp256r1 | secp384r1 | secp521r1.

-type padding() :: rsa_pkcs1_padding | rsa_pkcs1_pss_padding.

-type digest_type() :: sha256 | sha384 | sha512.

-file("src/ywt/internal/core.gleam", 72).
?DOC(false).
-spec bits_decoder() -> gleam@dynamic@decode:decoder(bitstring()).
bits_decoder() ->
    gleam@dynamic@decode:then(
        {decoder, fun gleam@dynamic@decode:decode_string/1},
        fun(Str) -> case ywt@internal@base64url:decode(Str) of
                {ok, Bits} ->
                    gleam@dynamic@decode:success(Bits);

                {error, _} ->
                    gleam@dynamic@decode:failure(<<>>, <<"Base64Url"/utf8>>)
            end end
    ).

-file("src/ywt/internal/core.gleam", 36).
?DOC(false).
-spec int_decoder() -> gleam@dynamic@decode:decoder(bigi:big_int()).
int_decoder() ->
    gleam@dynamic@decode:then(
        bits_decoder(),
        fun(Bits) -> case bigi_ffi:from_bytes(Bits, big_endian, unsigned) of
                {ok, Int} ->
                    gleam@dynamic@decode:success(Int);

                {error, _} ->
                    gleam@dynamic@decode:failure(
                        bigi_ffi:zero(),
                        <<"BigInt"/utf8>>
                    )
            end end
    ).

-file("src/ywt/internal/core.gleam", 44).
?DOC(false).
-spec bits_to_json(bitstring()) -> gleam@json:json().
bits_to_json(Bits) ->
    gleam@json:string(gleam@bit_array:base64_url_encode(Bits, false)).

-file("src/ywt/internal/core.gleam", 54).
?DOC(false).
-spec int_byte_size(bigi:big_int(), integer()) -> integer().
int_byte_size(Int, Bytes) ->
    case bigi_ffi:compare(Int, bigi_ffi:zero()) of
        gt ->
            int_byte_size(bigi_ffi:bitwise_shift_right(Int, 8), Bytes + 1);

        _ ->
            Bytes
    end.

-file("src/ywt/internal/core.gleam", 48).
?DOC(false).
-spec int_to_json(bigi:big_int()) -> gleam@json:json().
int_to_json(Int) ->
    Size = int_byte_size(Int, 0),
    Bytes@1 = case bigi_ffi:to_bytes(Int, big_endian, unsigned, Size) of
        {ok, Bytes} -> Bytes;
        _assert_fail ->
            erlang:error(#{gleam_error => let_assert,
                        message => <<"Pattern match failed, no pattern matched the value."/utf8>>,
                        file => <<?FILEPATH/utf8>>,
                        module => <<"ywt/internal/core"/utf8>>,
                        function => <<"int_to_json"/utf8>>,
                        line => 50,
                        value => _assert_fail,
                        start => 1615,
                        'end' => 1693,
                        pattern_start => 1626,
                        pattern_end => 1635})
    end,
    gleam@json:string(gleam@bit_array:base64_url_encode(Bytes@1, false)).

-file("src/ywt/internal/core.gleam", 61).
?DOC(false).
-spec rsa_modulus_is_large_enough(bigi:big_int()) -> boolean().
rsa_modulus_is_large_enough(Modulus) ->
    Minimum_bits = 2048,
    Minimum_modulus = bigi_ffi:bitwise_shift_left(
        bigi_ffi:one(),
        Minimum_bits - 1
    ),
    case bigi_ffi:compare(Modulus, Minimum_modulus) of
        lt ->
            false;

        eq ->
            true;

        gt ->
            true
    end.

-file("src/ywt/internal/core.gleam", 80).
?DOC(false).
-spec bits_of_length_decoder(integer()) -> gleam@dynamic@decode:decoder(bitstring()).
bits_of_length_decoder(Byte_count) ->
    gleam@dynamic@decode:then(
        bits_decoder(),
        fun(Bits) -> case erlang:bit_size(Bits) =:= (Byte_count * 8) of
                true ->
                    gleam@dynamic@decode:success(Bits);

                false ->
                    gleam@dynamic@decode:failure(
                        <<>>,
                        <<"Base64UrlLength"/utf8>>
                    )
            end end
    ).

-file("src/ywt/internal/core.gleam", 97).
?DOC(false).
-spec curve_decoder() -> gleam@dynamic@decode:decoder(named_curve()).
curve_decoder() ->
    gleam@dynamic@decode:then(
        {decoder, fun gleam@dynamic@decode:decode_string/1},
        fun(Crv) -> case Crv of
                <<"P-256"/utf8>> ->
                    gleam@dynamic@decode:success(secp256r1);

                <<"P-384"/utf8>> ->
                    gleam@dynamic@decode:success(secp384r1);

                <<"P-521"/utf8>> ->
                    gleam@dynamic@decode:success(secp521r1);

                _ ->
                    gleam@dynamic@decode:failure(secp256r1, <<"crv"/utf8>>)
            end end
    ).

-file("src/ywt/internal/core.gleam", 114).
?DOC(false).
-spec named_curve(named_curve()) -> binary().
named_curve(Curve) ->
    case Curve of
        secp256r1 ->
            <<"P-256"/utf8>>;

        secp384r1 ->
            <<"P-384"/utf8>>;

        secp521r1 ->
            <<"P-521"/utf8>>
    end.

-file("src/ywt/internal/core.gleam", 122).
?DOC(false).
-spec named_curve_size(named_curve()) -> integer().
named_curve_size(Curve) ->
    case Curve of
        secp256r1 ->
            32;

        secp384r1 ->
            48;

        secp521r1 ->
            66
    end.

-file("src/ywt/internal/core.gleam", 136).
?DOC(false).
-spec rsa_padding(padding()) -> binary().
rsa_padding(Padding) ->
    case Padding of
        rsa_pkcs1_padding ->
            <<"RSASSA-PKCS1-v1_5"/utf8>>;

        rsa_pkcs1_pss_padding ->
            <<"RSA-PSS"/utf8>>
    end.

-file("src/ywt/internal/core.gleam", 150).
?DOC(false).
-spec digest_type(digest_type()) -> binary().
digest_type(Digest_type) ->
    case Digest_type of
        sha256 ->
            <<"SHA-256"/utf8>>;

        sha384 ->
            <<"SHA-384"/utf8>>;

        sha512 ->
            <<"SHA-512"/utf8>>
    end.

-file("src/ywt/internal/core.gleam", 158).
?DOC(false).
-spec digest_size(digest_type()) -> integer().
digest_size(Digest_type) ->
    case Digest_type of
        sha256 ->
            32;

        sha384 ->
            48;

        sha512 ->
            64
    end.