-module(glethers@signer).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).

-export([sign_hash/2, sign_typed_data/4, sign_message/2, verify_signature/3]).
-export_type([signer/0]).

-type signer() :: {signer,
        glethers@provider:provider(),
        glethers@signer@signing_key:private_key()}.

-spec sign_hash(
    glethers@signer@signing_key:private_key(),
    glethers@hash@message:hash()
) -> secp256k1_gleam:signature().
sign_hash(Private_key, Hash) ->
    Private_key@1 = begin
        _pipe = Private_key,
        glethers@signer@signing_key:to_bit_array(_pipe)
    end,
    Message = begin
        _pipe@1 = Hash,
        glethers@hash@message:to_bit_array(_pipe@1)
    end,
    _assert_subject = secp256k1_gleam:sign(Message, Private_key@1),
    {ok, Signature} = case _assert_subject of
        {ok, _} -> _assert_subject;
        _assert_fail ->
            erlang:error(#{gleam_error => let_assert,
                        message => <<"Assertion pattern match failed"/utf8>>,
                        value => _assert_fail,
                        module => <<"glethers/signer"/utf8>>,
                        function => <<"sign_hash"/utf8>>,
                        line => 17})
    end,
    Signature.

-spec sign_typed_data(
    glethers@signer@signing_key:private_key(),
    glethers@hash@typed_data:typed_data_domain(),
    HVV,
    fun((HVV) -> {binary(),
        list({binary(), glethers@hash@typed_data:complex_field()})})
) -> secp256k1_gleam:signature().
sign_typed_data(Private_key, Domain, Struct, Encoder) ->
    Hash = glethers@hash@typed_data:hash_message(Domain, Struct, Encoder),
    sign_hash(Private_key, Hash).

-spec sign_message(glethers@signer@signing_key:private_key(), binary()) -> secp256k1_gleam:signature().
sign_message(Private_key, Message) ->
    Hash = glethers@hash@message:hash_message(Message),
    sign_hash(Private_key, Hash).

-spec verify_signature(
    glethers@signer@signing_key:private_key(),
    binary(),
    secp256k1_gleam:signature()
) -> boolean().
verify_signature(Private_key, Message, Signature) ->
    Private_key@1 = begin
        _pipe = Private_key,
        glethers@signer@signing_key:to_bit_array(_pipe)
    end,
    _assert_subject = 'Elixir.ExSecp256k1':create_public_key(Private_key@1),
    {ok, Public_key} = case _assert_subject of
        {ok, _} -> _assert_subject;
        _assert_fail ->
            erlang:error(#{gleam_error => let_assert,
                        message => <<"Assertion pattern match failed"/utf8>>,
                        value => _assert_fail,
                        module => <<"glethers/signer"/utf8>>,
                        function => <<"verify_signature"/utf8>>,
                        line => 42})
    end,
    Hash = begin
        _pipe@1 = glethers@hash@message:hash_message(Message),
        glethers@hash@message:to_bit_array(_pipe@1)
    end,
    case secp256k1_gleam:verify(Hash, Signature, Public_key) of
        {ok, _} ->
            true;

        {error, _} ->
            false
    end.