ewe

-module(ewe).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/ewe.gleam").
-export([ip_address_to_string/1, get_client_info/1, get_server_info/1, text/2, bytes/2, bits/2, string_tree/2, empty/1, json/2, new/1, bind/2, bind_all/1, with_port/2, with_random_port/1, with_ipv6/1, with_tls/3, with_name/2, on_start/2, on_crash/2, start/1, supervised/1, read_body/2, with_read_body/3, continue/0, stop/0, stop_abnormal/1, upgrade_websocket/2, use_expression/1]).
-export_type([ip_address/0, server_info/0, response_body/0, builder/1, body_error/0, exit_reason/0, next/0, websocket_message/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.

-type ip_address() :: {ip_v4, integer(), integer(), integer(), integer()} |
    {ip_v6,
        integer(),
        integer(),
        integer(),
        integer(),
        integer(),
        integer(),
        integer(),
        integer()}.

-type server_info() :: {server_info,
        gleam@http:scheme(),
        ip_address(),
        integer()}.

-opaque response_body() :: {text_data, binary()} |
    {bytes_data, gleam@bytes_tree:bytes_tree()} |
    {bits_data, bitstring()} |
    {string_tree_data, gleam@string_tree:string_tree()} |
    {websocket_connection,
        gleam@erlang@process:selector(gleam@erlang@process:down())} |
    empty.

-opaque builder(KQS) :: {builder,
        fun((gleam@http@request:request(KQS)) -> gleam@http@response:response(response_body())),
        integer(),
        binary(),
        boolean(),
        gleam@option:option({binary(), binary()}),
        fun((server_info()) -> nil),
        gleam@http@response:response(response_body()),
        gleam@erlang@process:name(ewe@internal@info:message(server_info()))}.

-type body_error() :: body_too_large | invalid_body.

-type exit_reason() :: normal | {abnormal, binary()}.

-opaque next() :: continue | {stop, exit_reason()}.

-type websocket_message() :: {text, binary()} | {binary, bitstring()}.

-file("src/ewe.gleam", 54).
-spec glisten_to_ewe_ip(glisten:ip_address()) -> ip_address().
glisten_to_ewe_ip(Ip) ->
    case Ip of
        {ip_v4, N1, N2, N3, N4} ->
            {ip_v4, N1, N2, N3, N4};

        {ip_v6, N1@1, N2@1, N3@1, N4@1, N5, N6, N7, N8} ->
            {ip_v6, N1@1, N2@1, N3@1, N4@1, N5, N6, N7, N8}
    end.

-file("src/ewe.gleam", 62).
-spec glisten_options_to_ewe_ip(glisten@socket@options:ip_address()) -> ip_address().
glisten_options_to_ewe_ip(Ip) ->
    case Ip of
        {ip_v4, N1, N2, N3, N4} ->
            {ip_v4, N1, N2, N3, N4};

        {ip_v6, N1@1, N2@1, N3@1, N4@1, N5, N6, N7, N8} ->
            {ip_v6, N1@1, N2@1, N3@1, N4@1, N5, N6, N7, N8}
    end.

-file("src/ewe.gleam", 70).
-spec ewe_to_glisten_ip(ip_address()) -> glisten:ip_address().
ewe_to_glisten_ip(Ip) ->
    case Ip of
        {ip_v4, N1, N2, N3, N4} ->
            {ip_v4, N1, N2, N3, N4};

        {ip_v6, N1@1, N2@1, N3@1, N4@1, N5, N6, N7, N8} ->
            {ip_v6, N1@1, N2@1, N3@1, N4@1, N5, N6, N7, N8}
    end.

-file("src/ewe.gleam", 49).
?DOC(" Converts an `IpAddress` to a string for later printing.\n").
-spec ip_address_to_string(ip_address()) -> binary().
ip_address_to_string(Address) ->
    _pipe = ewe_to_glisten_ip(Address),
    glisten:ip_address_to_string(_pipe).

-file("src/ewe.gleam", 89).
?DOC(" Performs an attempt to get the client's IP address and port.\n").
-spec get_client_info(ewe@internal@http:connection()) -> {ok,
        {ip_address(), integer()}} |
    {error, nil}.
get_client_info(Connection) ->
    _pipe = glisten@transport:peername(
        erlang:element(2, Connection),
        erlang:element(3, Connection)
    ),
    gleam@result:map(
        _pipe,
        fun(Tuple) ->
            {Ip, Port} = Tuple,
            {glisten_options_to_ewe_ip(Ip), Port}
        end
    ).

-file("src/ewe.gleam", 100).
?DOC(
    " Retrieves server's information. Requires the same name as the one used in\n"
    " `ewe.with_name` and server to be started. Otherwise, will crash the program.\n"
).
-spec get_server_info(
    gleam@erlang@process:name(ewe@internal@info:message(server_info()))
) -> {ok, server_info()} | {error, nil}.
get_server_info(Name) ->
    ewe@internal@info:get(gleam@erlang@process:named_subject(Name)).

-file("src/ewe.gleam", 129).
-spec transform_response_body(gleam@http@response:response(response_body())) -> gleam@http@response:response(ewe@internal@http:response_body()).
transform_response_body(Resp) ->
    gleam@http@response:set_body(Resp, case erlang:element(4, Resp) of
            {text_data, Text} ->
                {text_data, Text};

            {bytes_data, Bytes} ->
                {bytes_data, Bytes};

            {bits_data, Bits} ->
                {bits_data, Bits};

            {string_tree_data, String_tree} ->
                {string_tree_data, String_tree};

            {websocket_connection, Selector} ->
                {websocket_connection, Selector};

            empty ->
                empty
        end).

-file("src/ewe.gleam", 145).
?DOC(
    " Sets response body from string, sets `content-type` to\n"
    " `text/plain; charset=utf-8` and `content-length` headers.\n"
).
-spec text(gleam@http@response:response(any()), binary()) -> gleam@http@response:response(response_body()).
text(Response, Text) ->
    _pipe = gleam@http@response:set_body(Response, {text_data, Text}),
    _pipe@1 = gleam@http@response:set_header(
        _pipe,
        <<"content-type"/utf8>>,
        <<"text/plain; charset=utf-8"/utf8>>
    ),
    gleam@http@response:set_header(
        _pipe@1,
        <<"content-length"/utf8>>,
        erlang:integer_to_binary(erlang:byte_size(Text))
    ).

-file("src/ewe.gleam", 157).
?DOC(
    " Sets response body from bytes, sets `content-length` header. Doesn't set\n"
    " `content-type` header.\n"
).
-spec bytes(gleam@http@response:response(any()), gleam@bytes_tree:bytes_tree()) -> gleam@http@response:response(response_body()).
bytes(Response, Bytes) ->
    _pipe = gleam@http@response:set_body(Response, {bytes_data, Bytes}),
    gleam@http@response:set_header(
        _pipe,
        <<"content-length"/utf8>>,
        erlang:integer_to_binary(erlang:iolist_size(Bytes))
    ).

-file("src/ewe.gleam", 168).
?DOC(
    " Sets response body from bits, sets `content-length` header. Doesn't set\n"
    " `content-type` header.\n"
).
-spec bits(gleam@http@response:response(any()), bitstring()) -> gleam@http@response:response(response_body()).
bits(Response, Bits) ->
    _pipe = gleam@http@response:set_body(Response, {bits_data, Bits}),
    gleam@http@response:set_header(
        _pipe,
        <<"content-length"/utf8>>,
        erlang:integer_to_binary(erlang:byte_size(Bits))
    ).

-file("src/ewe.gleam", 179).
?DOC(
    " Sets response body from string tree, sets `content-length` header. Doesn't\n"
    " set `content-type` header.\n"
).
-spec string_tree(
    gleam@http@response:response(any()),
    gleam@string_tree:string_tree()
) -> gleam@http@response:response(response_body()).
string_tree(Response, String_tree) ->
    _pipe = gleam@http@response:set_body(
        Response,
        {string_tree_data, String_tree}
    ),
    gleam@http@response:set_header(
        _pipe,
        <<"content-length"/utf8>>,
        erlang:integer_to_binary(erlang:iolist_size(String_tree))
    ).

-file("src/ewe.gleam", 192).
?DOC(" Sets response body to empty, sets `content-length` header to `0`.\n").
-spec empty(gleam@http@response:response(any())) -> gleam@http@response:response(response_body()).
empty(Response) ->
    _pipe = gleam@http@response:set_body(Response, empty),
    gleam@http@response:set_header(
        _pipe,
        <<"content-length"/utf8>>,
        <<"0"/utf8>>
    ).

-file("src/ewe.gleam", 201).
?DOC(
    " Sets response body from string tree (use `gleam_json` package and encode\n"
    " using `json.to_string_tree`), sets `content-type` to `application/json;\n"
    " charset=utf-8` and `content-length` headers.\n"
).
-spec json(gleam@http@response:response(any()), gleam@string_tree:string_tree()) -> gleam@http@response:response(response_body()).
json(Response, Json) ->
    _pipe = string_tree(Response, Json),
    gleam@http@response:set_header(
        _pipe,
        <<"content-type"/utf8>>,
        <<"application/json; charset=utf-8"/utf8>>
    ).

-file("src/ewe.gleam", 248).
?DOC(
    " Creates new server builder with handler provided.\n"
    " \n"
    " Default configuration:\n"
    " - port: `8080`\n"
    " - interface: `127.0.0.1`\n"
    " - No ipv6 support\n"
    " - No TLS support\n"
    " - Default process name for server information retrieval\n"
    " - on_start: prints `Listening on <scheme>://<ip_address>:<port>`\n"
    " - on_crash: empty 500 response\n"
).
-spec new(
    fun((gleam@http@request:request(KRT)) -> gleam@http@response:response(response_body()))
) -> builder(KRT).
new(Handler) ->
    {builder,
        Handler,
        8080,
        <<"127.0.0.1"/utf8>>,
        false,
        none,
        fun(Server) ->
            Address = case erlang:element(3, Server) of
                {ip_v6, _, _, _, _, _, _, _, _} ->
                    <<<<"["/utf8,
                            (ip_address_to_string(erlang:element(3, Server)))/binary>>/binary,
                        "]"/utf8>>;

                {ip_v4, _, _, _, _} ->
                    ip_address_to_string(erlang:element(3, Server))
            end,
            Url = <<<<<<<<(gleam@http:scheme_to_string(
                                erlang:element(2, Server)
                            ))/binary,
                            "://"/utf8>>/binary,
                        Address/binary>>/binary,
                    ":"/utf8>>/binary,
                (erlang:integer_to_binary(erlang:element(4, Server)))/binary>>,
            gleam_stdlib:println(<<"Listening on "/utf8, Url/binary>>)
        end,
        begin
            _pipe = gleam@http@response:new(500),
            gleam@http@response:set_body(_pipe, empty)
        end,
        gleam_erlang_ffi:new_name(<<"ewe_server_info"/utf8>>)}.

-file("src/ewe.gleam", 279).
?DOC(" Binds server to a specific interface. Crashes program if interface is invalid.\n").
-spec bind(builder(KRX), binary()) -> builder(KRX).
bind(Builder, Interface) ->
    {builder,
        erlang:element(2, Builder),
        erlang:element(3, Builder),
        Interface,
        erlang:element(5, Builder),
        erlang:element(6, Builder),
        erlang:element(7, Builder),
        erlang:element(8, Builder),
        erlang:element(9, Builder)}.

-file("src/ewe.gleam", 285).
?DOC(" Binds server to all interfaces.\n").
-spec bind_all(builder(KSA)) -> builder(KSA).
bind_all(Builder) ->
    {builder,
        erlang:element(2, Builder),
        erlang:element(3, Builder),
        <<"0.0.0.0"/utf8>>,
        erlang:element(5, Builder),
        erlang:element(6, Builder),
        erlang:element(7, Builder),
        erlang:element(8, Builder),
        erlang:element(9, Builder)}.

-file("src/ewe.gleam", 291).
?DOC(" Sets listening port for server.\n").
-spec with_port(builder(KSD), integer()) -> builder(KSD).
with_port(Builder, Port) ->
    {builder,
        erlang:element(2, Builder),
        Port,
        erlang:element(4, Builder),
        erlang:element(5, Builder),
        erlang:element(6, Builder),
        erlang:element(7, Builder),
        erlang:element(8, Builder),
        erlang:element(9, Builder)}.

-file("src/ewe.gleam", 297).
?DOC(" Sets listening port for server to a random port. Useful for testing.\n").
-spec with_random_port(builder(KSG)) -> builder(KSG).
with_random_port(Builder) ->
    {builder,
        erlang:element(2, Builder),
        0,
        erlang:element(4, Builder),
        erlang:element(5, Builder),
        erlang:element(6, Builder),
        erlang:element(7, Builder),
        erlang:element(8, Builder),
        erlang:element(9, Builder)}.

-file("src/ewe.gleam", 303).
?DOC(" Enables IPv6 support.\n").
-spec with_ipv6(builder(KSJ)) -> builder(KSJ).
with_ipv6(Builder) ->
    {builder,
        erlang:element(2, Builder),
        erlang:element(3, Builder),
        erlang:element(4, Builder),
        true,
        erlang:element(6, Builder),
        erlang:element(7, Builder),
        erlang:element(8, Builder),
        erlang:element(9, Builder)}.

-file("src/ewe.gleam", 309).
?DOC(" Enables TLS support, requires certificate and key file.\n").
-spec with_tls(builder(KSM), binary(), binary()) -> builder(KSM).
with_tls(Builder, Certificate, Keyfile) ->
    Cert = case ewe@internal@file:open(Certificate) of
        {ok, _} ->
            Certificate;

        {error, _} ->
            erlang:error(#{gleam_error => panic,
                    message => <<"Failed to find cert file"/utf8>>,
                    file => <<?FILEPATH/utf8>>,
                    module => <<"ewe"/utf8>>,
                    function => <<"with_tls"/utf8>>,
                    line => 316})
    end,
    Key = case ewe@internal@file:open(Keyfile) of
        {ok, _} ->
            Keyfile;

        {error, _} ->
            erlang:error(#{gleam_error => panic,
                    message => <<"Failed to find key file"/utf8>>,
                    file => <<?FILEPATH/utf8>>,
                    module => <<"ewe"/utf8>>,
                    function => <<"with_tls"/utf8>>,
                    line => 321})
    end,
    {builder,
        erlang:element(2, Builder),
        erlang:element(3, Builder),
        erlang:element(4, Builder),
        erlang:element(5, Builder),
        {some, {Cert, Key}},
        erlang:element(7, Builder),
        erlang:element(8, Builder),
        erlang:element(9, Builder)}.

-file("src/ewe.gleam", 330).
?DOC(
    " Sets a custom process name for server information retrieval, allowing to\n"
    " use `ewe.get_server_info` after server starts.\n"
).
-spec with_name(
    builder(KSP),
    gleam@erlang@process:name(ewe@internal@info:message(server_info()))
) -> builder(KSP).
with_name(Builder, Name) ->
    {builder,
        erlang:element(2, Builder),
        erlang:element(3, Builder),
        erlang:element(4, Builder),
        erlang:element(5, Builder),
        erlang:element(6, Builder),
        erlang:element(7, Builder),
        erlang:element(8, Builder),
        Name}.

-file("src/ewe.gleam", 339).
?DOC(" Sets a custom handler that will be called after server starts.\n").
-spec on_start(builder(KSU), fun((server_info()) -> nil)) -> builder(KSU).
on_start(Builder, On_start) ->
    {builder,
        erlang:element(2, Builder),
        erlang:element(3, Builder),
        erlang:element(4, Builder),
        erlang:element(5, Builder),
        erlang:element(6, Builder),
        On_start,
        erlang:element(8, Builder),
        erlang:element(9, Builder)}.

-file("src/ewe.gleam", 348).
?DOC(" Sets a custom response that will be sent when server crashes.\n").
-spec on_crash(builder(KSX), gleam@http@response:response(response_body())) -> builder(KSX).
on_crash(Builder, On_crash) ->
    {builder,
        erlang:element(2, Builder),
        erlang:element(3, Builder),
        erlang:element(4, Builder),
        erlang:element(5, Builder),
        erlang:element(6, Builder),
        erlang:element(7, Builder),
        On_crash,
        erlang:element(9, Builder)}.

-file("src/ewe.gleam", 359).
?DOC(" Starts the server.\n").
-spec start(builder(ewe@internal@http:connection())) -> {ok,
        gleam@otp@actor:started(gleam@otp@static_supervisor:supervisor())} |
    {error, gleam@otp@actor:start_error()}.
start(Builder) ->
    Name = gleam_erlang_ffi:new_name(<<"ewe_glisten"/utf8>>),
    Handler = fun(Req) ->
        transform_response_body((erlang:element(2, Builder))(Req))
    end,
    On_crash = transform_response_body(erlang:element(8, Builder)),
    Worker_name = erlang:element(9, Builder),
    Subject = gleam@erlang@process:named_subject(Worker_name),
    Info_worker = ewe@internal@info:start_worker(Worker_name),
    Glisten_supervisor = begin
        _pipe = glisten:new(
            fun(Conn) ->
                {ewe@internal@http:transform_connection(Conn), none}
            end,
            ewe@internal@handler:loop(Handler, On_crash)
        ),
        _pipe@1 = glisten:bind(_pipe, erlang:element(4, Builder)),
        _pipe@2 = (fun(Glisten_builder) -> case erlang:element(5, Builder) of
                true ->
                    glisten:with_ipv6(Glisten_builder);

                false ->
                    Glisten_builder
            end end)(_pipe@1),
        _pipe@3 = (fun(Glisten_builder@1) -> case erlang:element(6, Builder) of
                {some, {Cert, Key}} ->
                    glisten:with_tls(Glisten_builder@1, Cert, Key);

                none ->
                    Glisten_builder@1
            end end)(_pipe@2),
        _pipe@4 = glisten:start_with_listener_name(
            _pipe@3,
            erlang:element(3, Builder),
            Name
        ),
        gleam@result:map(
            _pipe@4,
            fun(Started) ->
                Scheme = case erlang:element(6, Builder) of
                    {some, {_, _}} ->
                        https;

                    none ->
                        http
                end,
                Server_info = glisten:get_server_info(Name, 10000),
                Ip_address = glisten_to_ewe_ip(erlang:element(3, Server_info)),
                Server = {server_info,
                    Scheme,
                    Ip_address,
                    erlang:element(2, Server_info)},
                ewe@internal@info:set(Subject, Server),
                (erlang:element(7, Builder))(Server),
                Started
            end
        )
    end,
    Glisten_child = gleam@otp@supervision:supervisor(
        fun() -> Glisten_supervisor end
    ),
    _pipe@5 = gleam@otp@static_supervisor:new(one_for_all),
    _pipe@6 = gleam@otp@static_supervisor:add(_pipe@5, Glisten_child),
    _pipe@7 = gleam@otp@static_supervisor:add(_pipe@6, Info_worker),
    gleam@otp@static_supervisor:start(_pipe@7).

-file("src/ewe.gleam", 423).
?DOC(" Creates a supervisor that can be appended to a supervision tree.\n").
-spec supervised(builder(ewe@internal@http:connection())) -> gleam@otp@supervision:child_specification(gleam@otp@static_supervisor:supervisor()).
supervised(Builder) ->
    gleam@otp@supervision:supervisor(fun() -> start(Builder) end).

-file("src/ewe.gleam", 445).
?DOC(
    " Reads body from a request. If request body is malformed, `InvalidBody`\n"
    " error is returned. On success, returns a request with body converted to\n"
    " `BitArray`.\n"
    " - When `transfer-encoding` header set as `chunked`, `BodyTooLarge` error is returned if\n"
    " accumulated body is larger than `size_limit`.\n"
    " - Ensures that `content-length` is in `size_limit` scope.\n"
).
-spec read_body(
    gleam@http@request:request(ewe@internal@http:connection()),
    integer()
) -> {ok, gleam@http@request:request(bitstring())} | {error, body_error()}.
read_body(Req, Size_limit) ->
    case ewe@internal@http:read_body(Req, Size_limit) of
        {ok, Req@1} ->
            {ok, Req@1};

        {error, body_too_large} ->
            {error, body_too_large};

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

-file("src/ewe.gleam", 460).
?DOC(
    " With this option, body is read before handler is called, making request\n"
    " body available in handler (`Request(BitArray)`). If body is invalid or too\n"
    " large, `on_failure` function is called.\n"
).
-spec with_read_body(
    builder(bitstring()),
    integer(),
    fun((body_error()) -> gleam@http@response:response(response_body()))
) -> builder(ewe@internal@http:connection()).
with_read_body(Builder, Size_limit, On_failure) ->
    Handler = fun(Req) -> case read_body(Req, Size_limit) of
            {ok, Req@1} ->
                (erlang:element(2, Builder))(Req@1);

            {error, E} ->
                On_failure(E)
        end end,
    {builder,
        Handler,
        erlang:element(3, Builder),
        erlang:element(4, Builder),
        erlang:element(5, Builder),
        erlang:element(6, Builder),
        erlang:element(7, Builder),
        erlang:element(8, Builder),
        erlang:element(9, Builder)}.

-file("src/ewe.gleam", 495).
?DOC(" Instructs WebSocket connection to continue processing.\n").
-spec continue() -> next().
continue() ->
    continue.

-file("src/ewe.gleam", 501).
?DOC(" Instructs WebSocket connection to stop.\n").
-spec stop() -> next().
stop() ->
    {stop, normal}.

-file("src/ewe.gleam", 507).
?DOC(" Instructs WebSocket connection to stop with abnormal reason.\n").
-spec stop_abnormal(binary()) -> next().
stop_abnormal(Reason) ->
    {stop, {abnormal, Reason}}.

-file("src/ewe.gleam", 511).
-spec to_internal_next(next()) -> ewe@internal@websocket:next().
to_internal_next(Next) ->
    case Next of
        continue ->
            continue;

        {stop, normal} ->
            {stop, normal};

        {stop, {abnormal, Reason}} ->
            {stop, {abnormal, Reason}}
    end.

-file("src/ewe.gleam", 525).
-spec transform_websocket_message(gramps@websocket:frame()) -> {ok,
        websocket_message()} |
    {error, nil}.
transform_websocket_message(Frame) ->
    case Frame of
        {data, {text_frame, Text}} ->
            _pipe = gleam@bit_array:to_string(Text),
            gleam@result:map(_pipe, fun(Field@0) -> {text, Field@0} end);

        {data, {binary_frame, Binary}} ->
            {ok, {binary, Binary}};

        _ ->
            {error, nil}
    end.

-file("src/ewe.gleam", 539).
?DOC(
    " Upgrade request to a WebSocket connection. If the initial request is not\n"
    " valid for WebSocket upgrade, 400 response is sent. Handler must return\n"
    " instruction on how WebSocket connection should proceed.\n"
).
-spec upgrade_websocket(
    gleam@http@request:request(ewe@internal@http:connection()),
    fun((websocket_message()) -> next())
) -> gleam@http@response:response(response_body()).
upgrade_websocket(Req, Handler) ->
    Handler@1 = fun(Msg) -> _pipe = transform_websocket_message(Msg),
        _pipe@1 = gleam@result:map(_pipe, Handler),
        _pipe@2 = gleam@result:unwrap(_pipe@1, continue()),
        to_internal_next(_pipe@2) end,
    Transport = erlang:element(2, erlang:element(4, Req)),
    Socket = erlang:element(3, erlang:element(4, Req)),
    Resp = begin
        gleam@result:'try'(
            begin
                _pipe@3 = ewe@internal@http:upgrade_websocket(
                    Req,
                    Transport,
                    Socket
                ),
                gleam@result:replace_error(
                    _pipe@3,
                    begin
                        _pipe@4 = gleam@http@response:new(400),
                        gleam@http@response:set_body(_pipe@4, empty)
                    end
                )
            end,
            fun(_) ->
                gleam@result:'try'(
                    begin
                        _pipe@5 = ewe@internal@websocket:start(
                            Transport,
                            Socket,
                            Handler@1
                        ),
                        gleam@result:replace_error(
                            _pipe@5,
                            begin
                                _pipe@6 = gleam@http@response:new(500),
                                gleam@http@response:set_body(_pipe@6, empty)
                            end
                        )
                    end,
                    fun(Selector) -> _pipe@7 = gleam@http@response:new(500),
                        _pipe@8 = gleam@http@response:set_body(
                            _pipe@7,
                            {websocket_connection, Selector}
                        ),
                        {ok, _pipe@8} end
                )
            end
        )
    end,
    gleam@result:unwrap_both(Resp).

-file("src/ewe.gleam", 607).
?DOC(
    " Experimental function that simplifies error handling in handlers when\n"
    " working with `Result` type.\n"
    " \n"
    " ## Example\n"
    " \n"
    " ```gleam\n"
    " pub fn handle_echo(\n"
    "   req: Request(ewe.Connection),\n"
    " ) -> Response(bytes_tree.BytesTree) {\n"
    "   let content_type =\n"
    "     request.get_header(req, \"content-type\")\n"
    "     |> result.unwrap(\"text/plain\")\n"
    "\n"
    "    // Start the use_expression block\n"
    "    use <- ewe.use_expression()\n"
    "\n"
    "    // Now you can use result.try with use expressions\n"
    "    // If any step fails, the error response is automatically returned\n"
    "    use req <- result.try(\n"
    "      ewe.read_body(req, 1024)\n"
    "      |> result.replace_error(\n"
    "        response.new(400)\n"
    "        |> ewe.json(error_json(\"Invalid request body\")),\n"
    "      ),\n"
    "    )\n"
    "\n"
    "    response.new(200)\n"
    "    |> ewe.bits(req.body)\n"
    "    |> response.set_header(\"content-type\", content_type)\n"
    "    |> Ok \n"
    "}\n"
    " ```\n"
).
-spec use_expression(
    fun(() -> {ok, gleam@http@response:response(response_body())} |
        {error, gleam@http@response:response(response_body())})
) -> gleam@http@response:response(response_body()).
use_expression(Handler) ->
    gleam@result:unwrap_both(Handler()).