-module(mist@http).
-compile(no_auto_import).

-export([from_header/1, parse_headers/3, read_data/3, parse_request/2, new_state/0, handler/1, handler_func/1]).
-export_type([packet_type/0, http_uri/0, http_packet/0, decoded_packet/0, decode_error/0, buffer/0, handler_error/0, state/0, http_response_body/0, handler_response/0]).

-type packet_type() :: http | httph_bin | http_bin.

-type http_uri() :: {abs_path, bitstring()}.

-type http_packet() :: {http_request,
                        gleam@erlang@atom:atom_(),
                        http_uri(),
                        {integer(), integer()}} |
    {http_header,
     integer(),
     gleam@erlang@atom:atom_(),
     bitstring(),
     bitstring()}.

-type decoded_packet() :: {binary_data, http_packet(), bitstring()} |
    {end_of_headers, bitstring()} |
    {more_data, gleam@option:option(integer())}.

-type decode_error() :: invalid_method |
    invalid_path |
    unknown_header |
    invalid_body.

-type buffer() :: {buffer, integer(), bitstring()}.

-type handler_error() :: {invalid_request, decode_error()} | not_found.

-type state() :: {state,
                  gleam@option:option(gleam@otp@process:timer()),
                  gleam@option:option(fun((mist@websocket:message(), glisten@tcp:socket()) -> {ok,
                                                                                               nil} |
                      {error, nil}))}.

-type http_response_body() :: {bit_builder_body,
                               gleam@bit_builder:bit_builder()} |
    {file_body, mist@file:file_descriptor(), binary(), integer(), integer()}.

-type handler_response() :: {response,
                             gleam@http@response:response(http_response_body())} |
    {upgrade,
     fun((mist@websocket:message(), glisten@tcp:socket()) -> {ok, nil} |
         {error, nil})}.

-spec from_header(bitstring()) -> binary().
from_header(Value) ->
    {ok, Value@2} = case gleam@bit_string:to_string(Value) of
        {ok, Value@1} -> {ok, Value@1};
        _try ->
            erlang:error(#{gleam_error => assert,
                           message => <<"Assertion pattern match failed"/utf8>>,
                           value => _try,
                           module => <<"mist/http"/utf8>>,
                           function => <<"from_header"/utf8>>,
                           line => 58})
    end,
    gleam@string:lowercase(Value@2).

-spec parse_headers(
    bitstring(),
    glisten@tcp:socket(),
    gleam@map:map_(binary(), binary())
) -> {ok, {gleam@map:map_(binary(), binary()), bitstring()}} |
    {error, decode_error()}.
parse_headers(Bs, Socket, Headers) ->
    case http_ffi:decode_packet(httph_bin, Bs, []) of
        {ok, {binary_data, {http_header, _@1, _@2, Field, Value}, Rest}} ->
            Field@1 = from_header(Field),
            {ok, Value@2} = case gleam@bit_string:to_string(Value) of
                {ok, Value@1} -> {ok, Value@1};
                _try ->
                    erlang:error(#{gleam_error => assert,
                                   message => <<"Assertion pattern match failed"/utf8>>,
                                   value => _try,
                                   module => <<"mist/http"/utf8>>,
                                   function => <<"parse_headers"/utf8>>,
                                   line => 75})
            end,
            _pipe = Headers,
            _pipe@1 = gleam@map:insert(_pipe, Field@1, Value@2),
            parse_headers(Rest, Socket, _pipe@1);

        {ok, {end_of_headers, Rest@1}} ->
            {ok, {Headers, Rest@1}};

        {ok, {more_data, Size}} ->
            Amount_to_read = gleam@option:unwrap(Size, 0),
            case read_data(Socket, {buffer, Amount_to_read, Bs}, unknown_header) of
                {error, _try@1} -> {error, _try@1};
                {ok, Next} ->
                    parse_headers(Next, Socket, Headers)
            end;

        _@3 ->
            {error, unknown_header}
    end.

-spec read_data(glisten@tcp:socket(), buffer(), decode_error()) -> {ok,
                                                                    bitstring()} |
    {error, decode_error()}.
read_data(Socket, Buffer, Error) ->
    To_read = gleam@int:min(erlang:element(2, Buffer), 1000000),
    Timeout = 15000,
    case begin
        _pipe = Socket,
        _pipe@1 = glisten@tcp:receive_timeout(_pipe, To_read, Timeout),
        gleam@result:replace_error(_pipe@1, Error)
    end of
        {error, _try} -> {error, _try};
        {ok, Data} ->
            Next_buffer = {buffer,
                           erlang:element(2, Buffer)
                           - To_read,
                           <<(erlang:element(3, Buffer))/bitstring,
                             Data/bitstring>>},
            case erlang:element(2, Next_buffer) > 0 of
                true ->
                    read_data(Socket, Next_buffer, Error);

                false ->
                    {ok, erlang:element(3, Next_buffer)}
            end
    end.

-spec parse_request(bitstring(), glisten@tcp:socket()) -> {ok,
                                                           gleam@http@request:request(bitstring())} |
    {error, decode_error()}.
parse_request(Bs, Socket) ->
    case http_ffi:decode_packet(http_bin, Bs, []) of
        {error, _try} -> {error, _try};
        {ok, {binary_data, Req, Rest}} ->
            {http_request, Method@1, {abs_path, Path@1}, _@2} = case Req of
                {http_request, Method, {abs_path, Path}, _@1} -> {http_request,
                                                                  Method,
                                                                  {abs_path,
                                                                   Path},
                                                                  _@1};
                _try@1 ->
                    erlang:error(#{gleam_error => assert,
                                   message => <<"Assertion pattern match failed"/utf8>>,
                                   value => _try@1,
                                   module => <<"mist/http"/utf8>>,
                                   function => <<"parse_request"/utf8>>,
                                   line => 120})
            end,
            case begin
                _pipe = Method@1,
                _pipe@1 = gleam@erlang@atom:to_string(_pipe),
                _pipe@2 = gleam@http:parse_method(_pipe@1),
                gleam@result:replace_error(_pipe@2, invalid_method)
            end of
                {error, _try@2} -> {error, _try@2};
                {ok, Method@2} ->
                    case parse_headers(Rest, Socket, gleam@map:new()) of
                        {error, _try@3} -> {error, _try@3};
                        {ok, {Headers, Rest@1}} ->
                            case begin
                                _pipe@3 = Path@1,
                                _pipe@4 = gleam@bit_string:to_string(_pipe@3),
                                gleam@result:replace_error(
                                    _pipe@4,
                                    invalid_path
                                )
                            end of
                                {error, _try@4} -> {error, _try@4};
                                {ok, Path@2} ->
                                    Body_size = begin
                                        _pipe@5 = Headers,
                                        _pipe@6 = gleam@map:get(
                                            _pipe@5,
                                            <<"content-length"/utf8>>
                                        ),
                                        _pipe@7 = gleam@result:then(
                                            _pipe@6,
                                            fun gleam@int:parse/1
                                        ),
                                        gleam@result:unwrap(_pipe@7, 0)
                                    end,
                                    Remaining = Body_size
                                    - gleam@bit_string:byte_size(Rest@1),
                                    case case {Body_size, Remaining} of
                                        {0, 0} ->
                                            {ok, <<>>};

                                        {0, _@3} ->
                                            {ok, Rest@1};

                                        {_@4, 0} ->
                                            {ok, Rest@1};

                                        {_@5, _@6} ->
                                            read_data(
                                                Socket,
                                                {buffer, Remaining, Rest@1},
                                                invalid_body
                                            )
                                    end of
                                        {error, _try@5} -> {error, _try@5};
                                        {ok, Body} ->
                                            Req@1 = begin
                                                _pipe@8 = gleam@http@request:new(
                                                    
                                                ),
                                                _pipe@9 = gleam@http@request:set_body(
                                                    _pipe@8,
                                                    Body
                                                ),
                                                _pipe@10 = gleam@http@request:set_method(
                                                    _pipe@9,
                                                    Method@2
                                                ),
                                                gleam@http@request:set_path(
                                                    _pipe@10,
                                                    Path@2
                                                )
                                            end,
                                            {ok,
                                             erlang:setelement(
                                                 3,
                                                 Req@1,
                                                 gleam@map:to_list(Headers)
                                             )}
                                    end
                            end
                    end
            end
    end.

-spec new_state() -> state().
new_state() ->
    {state, none, none}.

-spec handler(
    fun((gleam@http@request:request(bitstring())) -> gleam@http@response:response(gleam@bit_builder:bit_builder()))
) -> fun((glisten@tcp:handler_message(), glisten@tcp:loop_state(state())) -> gleam@otp@actor:next(glisten@tcp:loop_state(state()))).
handler(Handler) ->
    handler_func(
        fun(Req) ->
            _pipe = Req,
            _pipe@1 = Handler(_pipe),
            _pipe@2 = gleam@http@response:map(
                _pipe@1,
                fun(A) -> {bit_builder_body, A} end
            ),
            {response, _pipe@2}
        end
    ).

-spec handler_func(
    fun((gleam@http@request:request(bitstring())) -> handler_response())
) -> fun((glisten@tcp:handler_message(), glisten@tcp:loop_state(state())) -> gleam@otp@actor:next(glisten@tcp:loop_state(state()))).
handler_func(Handler) ->
    glisten@tcp:handler(
        fun(Msg, Socket_state) ->
            {loop_state, Socket, Sender, State} = Socket_state,
            case erlang:element(3, State) of
                {some, Handler@1} ->
                    case mist@websocket:frame_from_message(Msg) of
                        {ok, {text_frame, _@1, Payload}} ->
                            _pipe = Payload,
                            _pipe@1 = {text_message, _pipe},
                            _pipe@2 = (fun(Ws_msg) ->
                                gleam_erlang_ffi:rescue(
                                    fun() -> Handler@1(Ws_msg, Socket) end
                                )
                            end)(_pipe@1),
                            _pipe@3 = gleam@result:replace(
                                _pipe@2,
                                {continue, Socket_state}
                            ),
                            _pipe@4 = gleam@result:map_error(
                                _pipe@3,
                                fun(Err) ->
                                    mist@logger:error(Err),
                                    Err
                                end
                            ),
                            _pipe@5 = gleam@result:replace_error(
                                _pipe@4,
                                {stop, normal}
                            ),
                            gleam@result:unwrap_both(_pipe@5);

                        {error, _@2} ->
                            {stop, normal}
                    end;

                none ->
                    _@4 = case erlang:element(2, State) of
                        {some, T} ->
                            gleam@otp@process:cancel_timer(T);

                        _@3 ->
                            timer_not_found
                    end,
                    _pipe@6 = Msg,
                    _pipe@7 = parse_request(_pipe@6, Socket),
                    _pipe@8 = gleam@result:replace_error(
                        _pipe@7,
                        {stop, normal}
                    ),
                    _pipe@28 = gleam@result:map(
                        _pipe@8,
                        fun(Req) ->
                            case gleam_erlang_ffi:rescue(
                                fun() -> Handler(Req) end
                            ) of
                                {ok,
                                 {response,
                                  {response, _@5, _@6, {bit_builder_body, Body}} = Resp}} ->
                                    _pipe@9 = Resp,
                                    _pipe@10 = gleam@http@response:set_body(
                                        _pipe@9,
                                        Body
                                    ),
                                    _pipe@11 = mist@encoder:to_bit_builder(
                                        _pipe@10
                                    ),
                                    _pipe@12 = glisten@tcp:send(
                                        Socket,
                                        _pipe@11
                                    ),
                                    _pipe@13 = gleam@result:map(
                                        _pipe@12,
                                        fun(_) ->
                                            case gleam@http@response:get_header(
                                                Resp,
                                                <<"connection"/utf8>>
                                            ) of
                                                {ok, <<"close"/utf8>>} ->
                                                    glisten@tcp:close(Socket),
                                                    {stop, normal};

                                                _@7 ->
                                                    Timer = gleam@otp@process:send_after(
                                                        Sender,
                                                        10000,
                                                        close
                                                    ),
                                                    {continue,
                                                     erlang:setelement(
                                                         4,
                                                         Socket_state,
                                                         erlang:setelement(
                                                             2,
                                                             State,
                                                             {some, Timer}
                                                         )
                                                     )}
                                            end
                                        end
                                    ),
                                    _pipe@14 = gleam@result:replace_error(
                                        _pipe@13,
                                        {stop, normal}
                                    ),
                                    gleam@result:unwrap_both(_pipe@14);

                                {ok,
                                 {response,
                                  {response,
                                   _@8,
                                   _@9,
                                   {file_body,
                                    File_descriptor,
                                    Content_type,
                                    Offset,
                                    Length}} = Resp@1}} ->
                                    Header = begin
                                        _pipe@15 = Resp@1,
                                        _pipe@16 = gleam@http@response:prepend_header(
                                            _pipe@15,
                                            <<"content-length"/utf8>>,
                                            gleam@int:to_string(Length - Offset)
                                        ),
                                        _pipe@17 = gleam@http@response:prepend_header(
                                            _pipe@16,
                                            <<"content-type"/utf8>>,
                                            Content_type
                                        ),
                                        _pipe@18 = gleam@http@response:set_body(
                                            _pipe@17,
                                            gleam@bit_builder:new()
                                        ),
                                        (fun(R) ->
                                            mist@encoder:response_builder(
                                                erlang:element(2, Resp@1),
                                                erlang:element(3, R)
                                            )
                                        end)(_pipe@18)
                                    end,
                                    _pipe@19 = Socket,
                                    _pipe@20 = glisten@tcp:send(
                                        _pipe@19,
                                        Header
                                    ),
                                    _pipe@21 = gleam@result:map(
                                        _pipe@20,
                                        fun(_) ->
                                            mist@file:sendfile(
                                                File_descriptor,
                                                Socket,
                                                Offset,
                                                Length,
                                                []
                                            )
                                        end
                                    ),
                                    _pipe@22 = gleam@result:replace(
                                        _pipe@21,
                                        {continue, Socket_state}
                                    ),
                                    _pipe@23 = gleam@result:replace_error(
                                        _pipe@22,
                                        {stop, normal}
                                    ),
                                    gleam@result:unwrap_both(_pipe@23);

                                {ok, {upgrade, With_handler}} ->
                                    _pipe@24 = Req,
                                    _pipe@25 = mist@websocket:upgrade(
                                        Socket,
                                        _pipe@24
                                    ),
                                    _pipe@26 = gleam@result:replace(
                                        _pipe@25,
                                        {continue,
                                         erlang:setelement(
                                             4,
                                             Socket_state,
                                             erlang:setelement(
                                                 3,
                                                 State,
                                                 {some, With_handler}
                                             )
                                         )}
                                    ),
                                    _pipe@27 = gleam@result:replace_error(
                                        _pipe@26,
                                        {stop, normal}
                                    ),
                                    gleam@result:unwrap_both(_pipe@27);

                                {error, {exited, Msg@1} = Err@1} ->
                                    mist@logger:error(Err@1),
                                    _pipe@28 = gleam@http@response:new(500),
                                    _pipe@29 = gleam@http@response:set_body(
                                        _pipe@28,
                                        gleam@bit_builder:from_bit_string(
                                            <<"Internal Server Error"/utf8>>
                                        )
                                    ),
                                    _pipe@30 = gleam@http@response:prepend_header(
                                        _pipe@29,
                                        <<"content-length"/utf8>>,
                                        <<"21"/utf8>>
                                    ),
                                    _pipe@31 = mist@encoder:to_bit_builder(
                                        _pipe@30
                                    ),
                                    glisten@tcp:send(Socket, _pipe@31),
                                    glisten@tcp:close(Socket),
                                    {stop, {abnormal, Msg@1}};

                                {error, {thrown, Msg@1} = Err@1} ->
                                    mist@logger:error(Err@1),
                                    _pipe@28 = gleam@http@response:new(500),
                                    _pipe@29 = gleam@http@response:set_body(
                                        _pipe@28,
                                        gleam@bit_builder:from_bit_string(
                                            <<"Internal Server Error"/utf8>>
                                        )
                                    ),
                                    _pipe@30 = gleam@http@response:prepend_header(
                                        _pipe@29,
                                        <<"content-length"/utf8>>,
                                        <<"21"/utf8>>
                                    ),
                                    _pipe@31 = mist@encoder:to_bit_builder(
                                        _pipe@30
                                    ),
                                    glisten@tcp:send(Socket, _pipe@31),
                                    glisten@tcp:close(Socket),
                                    {stop, {abnormal, Msg@1}};

                                {error, {errored, Msg@1} = Err@1} ->
                                    mist@logger:error(Err@1),
                                    _pipe@28 = gleam@http@response:new(500),
                                    _pipe@29 = gleam@http@response:set_body(
                                        _pipe@28,
                                        gleam@bit_builder:from_bit_string(
                                            <<"Internal Server Error"/utf8>>
                                        )
                                    ),
                                    _pipe@30 = gleam@http@response:prepend_header(
                                        _pipe@29,
                                        <<"content-length"/utf8>>,
                                        <<"21"/utf8>>
                                    ),
                                    _pipe@31 = mist@encoder:to_bit_builder(
                                        _pipe@30
                                    ),
                                    glisten@tcp:send(Socket, _pipe@31),
                                    glisten@tcp:close(Socket),
                                    {stop, {abnormal, Msg@1}}
                            end
                        end
                    ),
                    gleam@result:unwrap_both(_pipe@28)
            end
        end
    ).