-module(anthropic@streaming@handler).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/anthropic/streaming/handler.gleam").
-export([stream_message/2, stream_message_with_callback/3, get_text_deltas/1, get_full_text/1, get_message_id/1, get_model/1, is_complete/1, has_error/1, get_error/1]).
-export_type([stream_result/0, stream_error/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(
    " Streaming HTTP handler for Anthropic API\n"
    "\n"
    " This module provides the HTTP handling for streaming responses from the\n"
    " Anthropic Messages API. It processes Server-Sent Events (SSE) and yields\n"
    " parsed streaming events.\n"
    "\n"
    " Note: Currently uses synchronous HTTP with SSE parsing. True streaming\n"
    " with real-time chunk processing can be added via Erlang interop if needed.\n"
).

-type stream_result() :: {stream_result,
        list(anthropic@types@streaming:stream_event())}.

-type stream_error() :: {http_error, anthropic@types@error:anthropic_error()} |
    {sse_parse_error, binary()} |
    {event_decode_error, binary()} |
    {api_error, integer(), binary()}.

-file("src/anthropic/streaming/handler.gleam", 172).
?DOC(" Parse an SSE response body into streaming events\n").
-spec parse_sse_response(binary()) -> {ok, stream_result()} |
    {error, stream_error()}.
parse_sse_response(Body) ->
    State = anthropic@streaming@sse:new_parser_state(),
    Parse_result = anthropic@streaming@sse:parse_chunk(State, Body),
    Events = begin
        _pipe = erlang:element(2, Parse_result),
        gleam@list:filter_map(
            _pipe,
            fun(Sse_event) ->
                case anthropic@streaming@decoder:decode_event(Sse_event) of
                    {ok, Event} ->
                        {ok, Event};

                    {error, _} ->
                        {error, nil}
                end
            end
        )
    end,
    Final_events = case anthropic@streaming@sse:flush(
        erlang:element(3, Parse_result)
    ) of
        {ok, Sse_event@1} ->
            case anthropic@streaming@decoder:decode_event(Sse_event@1) of
                {ok, Event@1} ->
                    lists:append(Events, [Event@1]);

                {error, _} ->
                    Events
            end;

        {error, _} ->
            Events
    end,
    {ok, {stream_result, Final_events}}.

-file("src/anthropic/streaming/handler.gleam", 217).
?DOC(" Convert ConnectError to string\n").
-spec connect_error_to_string(gleam@httpc:connect_error()) -> binary().
connect_error_to_string(Err) ->
    case Err of
        {posix, Code} ->
            <<"POSIX error: "/utf8, Code/binary>>;

        {tls_alert, Code@1, Detail} ->
            <<<<<<"TLS alert "/utf8, Code@1/binary>>/binary, ": "/utf8>>/binary,
                Detail/binary>>
    end.

-file("src/anthropic/streaming/handler.gleam", 201).
?DOC(" Convert httpc error to AnthropicError\n").
-spec http_error_to_anthropic_error(gleam@httpc:http_error()) -> anthropic@types@error:anthropic_error().
http_error_to_anthropic_error(Err) ->
    case Err of
        invalid_utf8_response ->
            anthropic@types@error:http_error(
                <<"Invalid UTF-8 in response"/utf8>>
            );

        {failed_to_connect, Ip4, Ip6} ->
            anthropic@types@error:network_error(
                <<<<<<<<"Failed to connect to server (IPv4: "/utf8,
                                (connect_error_to_string(Ip4))/binary>>/binary,
                            ", IPv6: "/utf8>>/binary,
                        (connect_error_to_string(Ip6))/binary>>/binary,
                    ")"/utf8>>
            );

        response_timeout ->
            anthropic@types@error:timeout_error(0)
    end.

-file("src/anthropic/streaming/handler.gleam", 139).
?DOC(" Make a streaming HTTP request\n").
-spec make_streaming_request(anthropic@client:client(), binary()) -> {ok,
        gleam@http@response:response(binary())} |
    {error, anthropic@types@error:anthropic_error()}.
make_streaming_request(Api_client, Body) ->
    Base_url = erlang:element(3, erlang:element(2, Api_client)),
    Full_url = <<Base_url/binary, (<<"/v1/messages"/utf8>>)/binary>>,
    gleam@result:'try'(
        begin
            _pipe = gleam@http@request:to(Full_url),
            gleam@result:map_error(
                _pipe,
                fun(_) ->
                    anthropic@types@error:config_error(
                        <<"Invalid URL: "/utf8, Full_url/binary>>
                    )
                end
            )
        end,
        fun(Req) ->
            Req@1 = begin
                _pipe@1 = Req,
                _pipe@2 = gleam@http@request:set_method(_pipe@1, post),
                _pipe@3 = gleam@http@request:set_header(
                    _pipe@2,
                    <<"content-type"/utf8>>,
                    <<"application/json"/utf8>>
                ),
                _pipe@4 = gleam@http@request:set_header(
                    _pipe@3,
                    <<"x-api-key"/utf8>>,
                    erlang:element(2, erlang:element(2, Api_client))
                ),
                _pipe@5 = gleam@http@request:set_header(
                    _pipe@4,
                    <<"anthropic-version"/utf8>>,
                    <<"2023-06-01"/utf8>>
                ),
                _pipe@6 = gleam@http@request:set_header(
                    _pipe@5,
                    <<"accept"/utf8>>,
                    <<"text/event-stream"/utf8>>
                ),
                gleam@http@request:set_body(_pipe@6, Body)
            end,
            _pipe@7 = gleam@httpc:configure(),
            _pipe@8 = gleam@httpc:timeout(
                _pipe@7,
                erlang:element(5, erlang:element(2, Api_client))
            ),
            _pipe@9 = gleam@httpc:dispatch(_pipe@8, Req@1),
            gleam@result:map_error(
                _pipe@9,
                fun(Err) -> http_error_to_anthropic_error(Err) end
            )
        end
    ).

-file("src/anthropic/streaming/handler.gleam", 76).
?DOC(
    " Stream a message request and return all events\n"
    "\n"
    " This function sends a streaming request to the Anthropic API,\n"
    " processes the SSE response, and returns all parsed events.\n"
    "\n"
    " ## Example\n"
    "\n"
    " ```gleam\n"
    " let request = create_request(model, messages, max_tokens)\n"
    "   |> with_stream(True)\n"
    "\n"
    " case stream_message(client, request) {\n"
    "   Ok(result) -> {\n"
    "     list.each(result.events, fn(event) {\n"
    "       io.println(event_type_string(event))\n"
    "     })\n"
    "   }\n"
    "   Error(err) -> handle_error(err)\n"
    " }\n"
    " ```\n"
).
-spec stream_message(
    anthropic@client:client(),
    anthropic@types@request:create_message_request()
) -> {ok, stream_result()} | {error, stream_error()}.
stream_message(Api_client, Message_request) ->
    Streaming_request = anthropic@types@request:with_stream(
        Message_request,
        true
    ),
    Body = anthropic@types@request:request_to_json_string(Streaming_request),
    gleam@result:'try'(
        begin
            _pipe = make_streaming_request(Api_client, Body),
            gleam@result:map_error(_pipe, fun(Err) -> {http_error, Err} end)
        end,
        fun(Http_response) -> case erlang:element(2, Http_response) of
                200 ->
                    parse_sse_response(erlang:element(4, Http_response));

                Status ->
                    {error,
                        {api_error, Status, erlang:element(4, Http_response)}}
            end end
    ).

-file("src/anthropic/streaming/handler.gleam", 121).
?DOC(
    " Stream a message request with a callback for each event\n"
    "\n"
    " This function is similar to `stream_message` but calls the provided\n"
    " callback function for each event as it is parsed.\n"
    "\n"
    " ## Example\n"
    "\n"
    " ```gleam\n"
    " stream_message_with_callback(client, request, fn(event) {\n"
    "   case event {\n"
    "     ContentBlockDeltaEventVariant(delta) -> {\n"
    "       case delta.delta {\n"
    "         TextContentDelta(text_delta) -> {\n"
    "           io.print(text_delta.text)\n"
    "         }\n"
    "         _ -> Nil\n"
    "       }\n"
    "     }\n"
    "     _ -> Nil\n"
    "   }\n"
    " })\n"
    " ```\n"
).
-spec stream_message_with_callback(
    anthropic@client:client(),
    anthropic@types@request:create_message_request(),
    fun((anthropic@types@streaming:stream_event()) -> nil)
) -> {ok, stream_result()} | {error, stream_error()}.
stream_message_with_callback(Api_client, Message_request, Callback) ->
    gleam@result:'try'(
        stream_message(Api_client, Message_request),
        fun(Result) ->
            gleam@list:each(erlang:element(2, Result), Callback),
            {ok, Result}
        end
    ).

-file("src/anthropic/streaming/handler.gleam", 229).
?DOC(" Filter events to only text deltas\n").
-spec get_text_deltas(list(anthropic@types@streaming:stream_event())) -> list(binary()).
get_text_deltas(Events) ->
    _pipe = Events,
    gleam@list:filter_map(_pipe, fun(Event) -> case Event of
                {content_block_delta_event_variant, Delta_event} ->
                    case erlang:element(3, Delta_event) of
                        {text_content_delta, Text_delta} ->
                            {ok, erlang:element(2, Text_delta)};

                        _ ->
                            {error, nil}
                    end;

                _ ->
                    {error, nil}
            end end).

-file("src/anthropic/streaming/handler.gleam", 245).
?DOC(" Get the full text from a stream of events\n").
-spec get_full_text(list(anthropic@types@streaming:stream_event())) -> binary().
get_full_text(Events) ->
    _pipe = get_text_deltas(Events),
    gleam@string:join(_pipe, <<""/utf8>>).

-file("src/anthropic/streaming/handler.gleam", 251).
?DOC(" Get the message ID from events\n").
-spec get_message_id(list(anthropic@types@streaming:stream_event())) -> {ok,
        binary()} |
    {error, nil}.
get_message_id(Events) ->
    _pipe = Events,
    gleam@list:find_map(_pipe, fun(Event) -> case Event of
                {message_start_event, Msg} ->
                    {ok, erlang:element(2, Msg)};

                _ ->
                    {error, nil}
            end end).

-file("src/anthropic/streaming/handler.gleam", 262).
?DOC(" Get the model from events\n").
-spec get_model(list(anthropic@types@streaming:stream_event())) -> {ok,
        binary()} |
    {error, nil}.
get_model(Events) ->
    _pipe = Events,
    gleam@list:find_map(_pipe, fun(Event) -> case Event of
                {message_start_event, Msg} ->
                    {ok, erlang:element(5, Msg)};

                _ ->
                    {error, nil}
            end end).

-file("src/anthropic/streaming/handler.gleam", 273).
?DOC(" Check if stream completed successfully\n").
-spec is_complete(list(anthropic@types@streaming:stream_event())) -> boolean().
is_complete(Events) ->
    gleam@list:any(Events, fun(Event) -> case Event of
                message_stop_event ->
                    true;

                _ ->
                    false
            end end).

-file("src/anthropic/streaming/handler.gleam", 283).
?DOC(" Check if stream ended with an error\n").
-spec has_error(list(anthropic@types@streaming:stream_event())) -> boolean().
has_error(Events) ->
    gleam@list:any(Events, fun(Event) -> case Event of
                {error_event, _} ->
                    true;

                _ ->
                    false
            end end).

-file("src/anthropic/streaming/handler.gleam", 293).
?DOC(" Get error from events if present\n").
-spec get_error(list(anthropic@types@streaming:stream_event())) -> {ok,
        anthropic@types@streaming:stream_error()} |
    {error, nil}.
get_error(Events) ->
    _pipe = Events,
    gleam@list:find_map(_pipe, fun(Event) -> case Event of
                {error_event, Err} ->
                    {ok, Err};

                _ ->
                    {error, nil}
            end end).