gsmtp

-module(smtp).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).

-export([send/4]).
-export_type([error/0]).

-type error() :: {tcp_error, mug:error()} |
    {invalid_server_code_error, binary(), integer()}.

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 16).
-spec tcp_connect(binary(), integer(), integer()) -> {ok, mug:socket()} |
    {error, error()}.
tcp_connect(Host, Port, Timeout) ->
    _pipe = mug:new(Host, Port),
    _pipe@1 = mug:timeout(_pipe, Timeout),
    _pipe@2 = mug:connect(_pipe@1),
    gleam@result:map_error(_pipe@2, fun(Field@0) -> {tcp_error, Field@0} end).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 23).
-spec tcp_send(mug:socket(), binary()) -> {ok, nil} | {error, error()}.
tcp_send(Socket, Message) ->
    logging:log(debug, <<"CLIENT: "/utf8, Message/binary>>),
    _pipe = mug:send(Socket, <<Message/binary>>),
    gleam@result:map_error(_pipe, fun(Field@0) -> {tcp_error, Field@0} end).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 30).
-spec tcp_receive(mug:socket(), integer()) -> {ok, bitstring()} |
    {error, error()}.
tcp_receive(Socket, Timeout) ->
    gleam@result:'try'(
        begin
            _pipe = mug:'receive'(Socket, Timeout),
            gleam@result:map_error(
                _pipe,
                fun(Field@0) -> {tcp_error, Field@0} end
            )
        end,
        fun(Packet) ->
            _assert_subject = gleam@bit_array:to_string(Packet),
            {ok, Packet_str} = case _assert_subject of
                {ok, _} -> _assert_subject;
                _assert_fail ->
                    erlang:error(#{gleam_error => let_assert,
                                message => <<"Pattern match failed, no pattern matched the value."/utf8>>,
                                value => _assert_fail,
                                module => <<"smtp"/utf8>>,
                                function => <<"tcp_receive"/utf8>>,
                                line => 36})
            end,
            logging:log(debug, <<"SERVER: "/utf8, Packet_str/binary>>),
            {ok, Packet}
        end
    ).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 42).
-spec check_server_code(integer(), bitstring()) -> {ok, nil} | {error, error()}.
check_server_code(Expected_code, Response) ->
    _assert_subject = gleam@bit_array:to_string(Response),
    {ok, Response_str} = case _assert_subject of
        {ok, _} -> _assert_subject;
        _assert_fail ->
            erlang:error(#{gleam_error => let_assert,
                        message => <<"Pattern match failed, no pattern matched the value."/utf8>>,
                        value => _assert_fail,
                        module => <<"smtp"/utf8>>,
                        function => <<"check_server_code"/utf8>>,
                        line => 43})
    end,
    Server_code = gleam@string:slice(Response_str, 0, 3),
    gleam@result:'try'(
        begin
            _pipe = gleam_stdlib:parse_int(Server_code),
            gleam@result:map_error(
                _pipe,
                fun(_) ->
                    {invalid_server_code_error, Server_code, Expected_code}
                end
            )
        end,
        fun(Parsed_code) -> case Parsed_code =:= Expected_code of
                true ->
                    {ok, nil};

                false ->
                    {error,
                        {invalid_server_code_error, Server_code, Expected_code}}
            end end
    ).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 60).
-spec cmd(mug:socket(), integer(), binary()) -> {ok, bitstring()} |
    {error, error()}.
cmd(Socket, Expected_code, Message) ->
    gleam@result:'try'(
        tcp_send(Socket, <<Message/binary, "\r\n"/utf8>>),
        fun(_) ->
            gleam@result:'try'(
                tcp_receive(Socket, 500),
                fun(Packet) ->
                    gleam@result:'try'(
                        check_server_code(Expected_code, Packet),
                        fun(_) -> {ok, Packet} end
                    )
                end
            )
        end
    ).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 70).
-spec opening_message(mug:socket(), integer()) -> {ok, nil} | {error, error()}.
opening_message(Socket, Timeout) ->
    gleam@result:'try'(
        tcp_receive(Socket, Timeout),
        fun(Packet) -> check_server_code(220, Packet) end
    ).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 75).
-spec find_extension(bitstring()) -> {ok, list(binary())} | {error, any()}.
find_extension(Response) ->
    Try_split_once = fun(Extension, Delimiter) ->
        _pipe = gleam@string:split_once(Extension, Delimiter),
        gleam@result:map(
            _pipe,
            fun(Extension@1) -> erlang:element(2, Extension@1) end
        )
    end,
    _assert_subject = gleam@bit_array:to_string(Response),
    {ok, Response_str} = case _assert_subject of
        {ok, _} -> _assert_subject;
        _assert_fail ->
            erlang:error(#{gleam_error => let_assert,
                        message => <<"Pattern match failed, no pattern matched the value."/utf8>>,
                        value => _assert_fail,
                        module => <<"smtp"/utf8>>,
                        function => <<"find_extension"/utf8>>,
                        line => 81})
    end,
    Extensions = begin
        _pipe@1 = gleam@string:split(Response_str, <<"\n"/utf8>>),
        _pipe@2 = gleam@list:drop(_pipe@1, 1),
        _pipe@4 = gleam@list:map(
            _pipe@2,
            fun(Extension@2) ->
                _pipe@3 = Try_split_once(Extension@2, <<"-"/utf8>>),
                gleam@result:'or'(
                    _pipe@3,
                    Try_split_once(Extension@2, <<" "/utf8>>)
                )
            end
        ),
        gleam@list:filter_map(_pipe@4, fun(X) -> X end)
    end,
    {ok, Extensions}.

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 95).
-spec has_extension(list(binary()), binary()) -> boolean().
has_extension(Extensions, Search) ->
    _pipe = gleam@list:find(
        Extensions,
        fun(Extension) -> gleam_stdlib:string_starts_with(Extension, Search) end
    ),
    gleam@result:is_ok(_pipe).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 112).
-spec helo(mug:socket(), binary()) -> {ok, bitstring()} | {error, error()}.
helo(Socket, Host) ->
    cmd(Socket, 250, <<"HELO "/utf8, Host/binary>>).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 100).
-spec ehlo(mug:socket(), binary()) -> {ok, list(binary())} | {error, error()}.
ehlo(Socket, Host) ->
    case cmd(Socket, 250, <<"EHLO "/utf8, Host/binary>>) of
        {ok, Response} ->
            find_extension(Response);

        {error, _} ->
            _pipe = helo(Socket, Host),
            gleam@result:map(_pipe, fun(_) -> [] end)
    end.

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 116).
-spec auth_plain(
    mug:socket(),
    list(binary()),
    gleam@option:option({binary(), binary()})
) -> {ok, bitstring()} | {error, error()}.
auth_plain(Socket, Extensions, Auth) ->
    Has_auth_extension = has_extension(Extensions, <<"AUTH"/utf8>>),
    case {Has_auth_extension, Auth} of
        {true, {some, {User, Password}}} ->
            User_and_password = <<<<<<"\x{0000}"/utf8, User/binary>>/binary,
                    "\x{0000}"/utf8>>/binary,
                Password/binary>>,
            Base64_encoded = gleam_stdlib:bit_array_base64_encode(
                <<User_and_password/binary>>,
                true
            ),
            cmd(Socket, 235, <<"AUTH PLAIN "/utf8, Base64_encoded/binary>>);

        {_, _} ->
            {ok, <<>>}
    end.

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 131).
-spec mail_from(mug:socket(), binary()) -> {ok, bitstring()} | {error, error()}.
mail_from(Socket, From) ->
    cmd(Socket, 250, <<<<"MAIL FROM:<"/utf8, From/binary>>/binary, ">"/utf8>>).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 135).
-spec rcpt_to(mug:socket(), list(binary())) -> {ok, bitstring()} |
    {error, error()}.
rcpt_to(Socket, To) ->
    cmd(
        Socket,
        250,
        <<<<"RCPT TO:<"/utf8, (gleam@string:join(To, <<","/utf8>>))/binary>>/binary,
            ">"/utf8>>
    ).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 139).
-spec data(mug:socket()) -> {ok, bitstring()} | {error, error()}.
data(Socket) ->
    cmd(Socket, 354, <<"DATA"/utf8>>).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 143).
-spec data_body(mug:socket(), builder:message()) -> {ok, bitstring()} |
    {error, error()}.
data_body(Socket, Message) ->
    Body = begin
        _pipe = <<""/utf8>>,
        _pipe@1 = gleam@string:append(
            _pipe,
            <<<<"Subject: "/utf8, (erlang:element(4, Message))/binary>>/binary,
                "\r\n"/utf8>>
        ),
        _pipe@2 = gleam@string:append(
            _pipe@1,
            <<<<"From: "/utf8, (erlang:element(2, Message))/binary>>/binary,
                "\r\n"/utf8>>
        ),
        _pipe@3 = gleam@string:append(
            _pipe@2,
            <<<<"To: "/utf8,
                    (gleam@string:join(erlang:element(3, Message), <<","/utf8>>))/binary>>/binary,
                "\r\n"/utf8>>
        ),
        _pipe@4 = gleam@string:append(_pipe@3, <<"\r\n"/utf8>>),
        _pipe@5 = gleam@string:append(_pipe@4, erlang:element(5, Message)),
        gleam@string:append(_pipe@5, <<"\r\n."/utf8>>)
    end,
    cmd(Socket, 250, Body).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 156).
-spec quit(mug:socket()) -> {ok, bitstring()} | {error, error()}.
quit(Socket) ->
    cmd(Socket, 221, <<"QUIT"/utf8>>).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 160).
-spec log_message(binary(), integer(), builder:message()) -> nil.
log_message(Host, Port, Message) ->
    logging:log(debug, <<"SENDING MAIL"/utf8>>),
    logging:log(
        debug,
        <<<<<<"HOST: "/utf8, Host/binary>>/binary, ":"/utf8>>/binary,
            (begin
                _pipe = Port,
                erlang:integer_to_binary(_pipe)
            end)/binary>>
    ),
    logging:log(debug, <<"FROM: "/utf8, (erlang:element(2, Message))/binary>>),
    logging:log(
        debug,
        <<"TO: "/utf8,
            (gleam@string:join(erlang:element(3, Message), <<", "/utf8>>))/binary>>
    ),
    logging:log(
        debug,
        <<"SUBJECT: "/utf8, (erlang:element(4, Message))/binary>>
    ),
    logging:log(debug, <<"BODY: "/utf8, (erlang:element(5, Message))/binary>>).

-file("/home/andre/Code/gleam/gsmtp/src/smtp.gleam", 169).
-spec send(
    binary(),
    integer(),
    gleam@option:option({binary(), binary()}),
    builder:message()
) -> {ok, nil} | {error, error()}.
send(Host, Port, Auth, Message) ->
    log_message(Host, Port, Message),
    Timeout = 500,
    gleam@result:'try'(
        tcp_connect(Host, Port, Timeout),
        fun(Socket) ->
            gleam@result:'try'(
                opening_message(Socket, Timeout),
                fun(_) ->
                    gleam@result:'try'(
                        ehlo(Socket, <<"localhost"/utf8>>),
                        fun(Extensions) ->
                            gleam@result:'try'(
                                auth_plain(Socket, Extensions, Auth),
                                fun(_) ->
                                    gleam@result:'try'(
                                        mail_from(
                                            Socket,
                                            erlang:element(2, Message)
                                        ),
                                        fun(_) ->
                                            gleam@result:'try'(
                                                rcpt_to(
                                                    Socket,
                                                    erlang:element(3, Message)
                                                ),
                                                fun(_) ->
                                                    gleam@result:'try'(
                                                        data(Socket),
                                                        fun(_) ->
                                                            gleam@result:'try'(
                                                                data_body(
                                                                    Socket,
                                                                    Message
                                                                ),
                                                                fun(_) ->
                                                                    gleam@result:'try'(
                                                                        quit(
                                                                            Socket
                                                                        ),
                                                                        fun(_) ->
                                                                            {ok,
                                                                                nil}
                                                                        end
                                                                    )
                                                                end
                                                            )
                                                        end
                                                    )
                                                end
                                            )
                                        end
                                    )
                                end
                            )
                        end
                    )
                end
            )
        end
    ).