pig

-module(pig@obs@session).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/pig/obs/session.gleam").
-export([iso_timestamp/0, format_event/1, start/1, stop/1, record/2, record_sync/2, decode_tool_call/0, decode_message/0, replay/1, start_consumer/1, supervised/2]).
-export_type([session_writer/0, writer_message/0, state/0, replay_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(
    " JSONL session writer — records SessionEvents to a file for replay.\n"
    "\n"
    " OTP actor that receives SessionEvents and appends them as JSONL lines.\n"
    " Two modes:\n"
    "   - `record()` — fire-and-forget, never blocks the agent.\n"
    "   - `record_sync()` — synchronous call, blocks until written. For testing.\n"
).

-opaque session_writer() :: {session_writer,
        gleam@erlang@process:subject(writer_message())}.

-type writer_message() :: {write_event, pig@obs@events:session_event()} |
    {write_event_sync,
        pig@obs@events:session_event(),
        gleam@erlang@process:subject(nil)} |
    stop.

-type state() :: {state, binary()}.

-type replay_error() :: {file_error, binary()} | {parse_error, binary()}.

-file("src/pig/obs/session.gleam", 40).
?DOC(" Get current ISO 8601 timestamp.\n").
-spec iso_timestamp() -> binary().
iso_timestamp() ->
    pig_obs_session_ffi:iso_timestamp().

-file("src/pig/obs/session.gleam", 618).
-spec error_to_json(pig_protocol@error:ai_error()) -> gleam@json:json().
error_to_json(Error) ->
    case Error of
        {api_error, Message} ->
            gleam@json:object(
                [{<<"type"/utf8>>, gleam@json:string(<<"api_error"/utf8>>)},
                    {<<"message"/utf8>>, gleam@json:string(Message)}]
            );

        rate_limited ->
            gleam@json:object(
                [{<<"type"/utf8>>, gleam@json:string(<<"rate_limited"/utf8>>)}]
            );

        timeout ->
            gleam@json:object(
                [{<<"type"/utf8>>, gleam@json:string(<<"timeout"/utf8>>)}]
            );

        {invalid_response, Detail} ->
            gleam@json:object(
                [{<<"type"/utf8>>,
                        gleam@json:string(<<"invalid_response"/utf8>>)},
                    {<<"detail"/utf8>>, gleam@json:string(Detail)}]
            )
    end.

-file("src/pig/obs/session.gleam", 641).
-spec reason_to_json(pig@obs@events:session_end_reason()) -> gleam@json:json().
reason_to_json(Reason) ->
    case Reason of
        normal_end ->
            gleam@json:object(
                [{<<"type"/utf8>>, gleam@json:string(<<"normal_end"/utf8>>)}]
            );

        {error_end, E} ->
            gleam@json:object(
                [{<<"type"/utf8>>, gleam@json:string(<<"error"/utf8>>)},
                    {<<"error"/utf8>>, error_to_json(E)}]
            );

        {max_iterations_exceeded, N} ->
            gleam@json:object(
                [{<<"type"/utf8>>,
                        gleam@json:string(<<"max_iterations_exceeded"/utf8>>)},
                    {<<"max_iterations"/utf8>>, gleam@json:int(N)}]
            );

        interrupted ->
            gleam@json:object(
                [{<<"type"/utf8>>, gleam@json:string(<<"interrupted"/utf8>>)}]
            )
    end.

-file("src/pig/obs/session.gleam", 610).
-spec tool_call_to_json(pig_protocol@message:tool_call()) -> gleam@json:json().
tool_call_to_json(Tc) ->
    gleam@json:object(
        [{<<"id"/utf8>>, gleam@json:string(erlang:element(2, Tc))},
            {<<"name"/utf8>>, gleam@json:string(erlang:element(3, Tc))},
            {<<"arguments"/utf8>>, gleam@json:string(erlang:element(4, Tc))}]
    ).

-file("src/pig/obs/session.gleam", 558).
-spec message_to_json(pig_protocol@message:message()) -> gleam@json:json().
message_to_json(Msg) ->
    case Msg of
        {user, Content} ->
            gleam@json:object(
                [{<<"role"/utf8>>, gleam@json:string(<<"user"/utf8>>)},
                    {<<"content"/utf8>>, gleam@json:string(Content)}]
            );

        {system, Content@1} ->
            gleam@json:object(
                [{<<"role"/utf8>>, gleam@json:string(<<"system"/utf8>>)},
                    {<<"content"/utf8>>, gleam@json:string(Content@1)}]
            );

        {assistant, Content@2, Tool_calls, Thinking, Stop_reason} ->
            Base_fields = [{<<"role"/utf8>>,
                    gleam@json:string(<<"assistant"/utf8>>)},
                {<<"content"/utf8>>, gleam@json:string(Content@2)},
                {<<"tool_calls"/utf8>>,
                    gleam@json:array(Tool_calls, fun tool_call_to_json/1)}],
            Fields_with_thinking = case Thinking of
                {some, T} ->
                    case T of
                        {thinking, Content@3} ->
                            lists:append(
                                Base_fields,
                                [{<<"thinking"/utf8>>,
                                        gleam@json:object(
                                            [{<<"content"/utf8>>,
                                                    gleam@json:string(Content@3)}]
                                        )}]
                            )
                    end;

                none ->
                    Base_fields
            end,
            Fields_with_stop_reason = case Stop_reason of
                {some, Sr} ->
                    lists:append(
                        Fields_with_thinking,
                        [{<<"stop_reason"/utf8>>,
                                pig_protocol@stop_reason:to_json(Sr)}]
                    );

                none ->
                    Fields_with_thinking
            end,
            gleam@json:object(Fields_with_stop_reason);

        {tool, Tool_call_id, Content@4} ->
            gleam@json:object(
                [{<<"role"/utf8>>, gleam@json:string(<<"tool"/utf8>>)},
                    {<<"tool_call_id"/utf8>>, gleam@json:string(Tool_call_id)},
                    {<<"content"/utf8>>, gleam@json:string(Content@4)}]
            )
    end.

-file("src/pig/obs/session.gleam", 664).
-spec hook_to_string(pig@obs@events:hook_point()) -> binary().
hook_to_string(Hook) ->
    case Hook of
        before_tool_call ->
            <<"before_tool_call"/utf8>>;

        after_tool_call ->
            <<"after_tool_call"/utf8>>;

        before_inference ->
            <<"before_inference"/utf8>>;

        after_inference ->
            <<"after_inference"/utf8>>;

        on_error ->
            <<"on_error"/utf8>>;

        on_complete ->
            <<"on_complete"/utf8>>;

        on_session_start ->
            <<"on_session_start"/utf8>>;

        on_session_shutdown ->
            <<"on_session_shutdown"/utf8>>
    end.

-file("src/pig/obs/session.gleam", 350).
?DOC(" Format a SessionEvent as a JSON string (pure function, no side effects).\n").
-spec format_event(pig@obs@events:session_event()) -> binary().
format_event(Event) ->
    Ts = iso_timestamp(),
    case Event of
        {session_started,
            Agent_id,
            Agent_name,
            Model,
            Provider_name,
            System_prompt} ->
            Fields = [{<<"ts"/utf8>>, gleam@json:string(Ts)},
                {<<"event"/utf8>>,
                    gleam@json:string(<<"session_started"/utf8>>)},
                {<<"model"/utf8>>, gleam@json:string(Model)}],
            With_agent_id = case Agent_id of
                {some, V} ->
                    lists:append(
                        Fields,
                        [{<<"agent_id"/utf8>>, gleam@json:string(V)}]
                    );

                none ->
                    Fields
            end,
            With_agent_name = case Agent_name of
                {some, V@1} ->
                    lists:append(
                        With_agent_id,
                        [{<<"agent_name"/utf8>>, gleam@json:string(V@1)}]
                    );

                none ->
                    With_agent_id
            end,
            With_provider = case Provider_name of
                {some, V@2} ->
                    lists:append(
                        With_agent_name,
                        [{<<"provider_name"/utf8>>, gleam@json:string(V@2)}]
                    );

                none ->
                    With_agent_name
            end,
            With_system = case System_prompt of
                {some, V@3} ->
                    lists:append(
                        With_provider,
                        [{<<"system_prompt"/utf8>>, gleam@json:string(V@3)}]
                    );

                none ->
                    With_provider
            end,
            _pipe = gleam@json:object(With_system),
            gleam@json:to_string(_pipe);

        {inference_started, Model@1, Message_count} ->
            _pipe@1 = gleam@json:object(
                [{<<"ts"/utf8>>, gleam@json:string(Ts)},
                    {<<"event"/utf8>>,
                        gleam@json:string(<<"inference_started"/utf8>>)},
                    {<<"model"/utf8>>, gleam@json:string(Model@1)},
                    {<<"message_count"/utf8>>, gleam@json:int(Message_count)}]
            ),
            gleam@json:to_string(_pipe@1);

        {inference_completed,
            Message,
            Response_id,
            Response_model,
            Stop_reason,
            Input_tokens,
            Output_tokens,
            Duration_ms,
            Input_messages} ->
            Fields@1 = [{<<"ts"/utf8>>, gleam@json:string(Ts)},
                {<<"event"/utf8>>,
                    gleam@json:string(<<"inference_completed"/utf8>>)},
                {<<"duration_ms"/utf8>>, gleam@json:int(Duration_ms)},
                {<<"message"/utf8>>, message_to_json(Message)},
                {<<"input_messages"/utf8>>,
                    gleam@json:array(Input_messages, fun message_to_json/1)}],
            With_response_id = case Response_id of
                {some, V@4} ->
                    lists:append(
                        Fields@1,
                        [{<<"response_id"/utf8>>, gleam@json:string(V@4)}]
                    );

                none ->
                    Fields@1
            end,
            With_response_model = case Response_model of
                {some, V@5} ->
                    lists:append(
                        With_response_id,
                        [{<<"response_model"/utf8>>, gleam@json:string(V@5)}]
                    );

                none ->
                    With_response_id
            end,
            With_stop_reason = case Stop_reason of
                {some, V@6} ->
                    lists:append(
                        With_response_model,
                        [{<<"stop_reason"/utf8>>,
                                pig_protocol@stop_reason:to_json(V@6)}]
                    );

                none ->
                    With_response_model
            end,
            With_input_tokens = case Input_tokens of
                {some, V@7} ->
                    lists:append(
                        With_stop_reason,
                        [{<<"input_tokens"/utf8>>, gleam@json:int(V@7)}]
                    );

                none ->
                    With_stop_reason
            end,
            With_output_tokens = case Output_tokens of
                {some, V@8} ->
                    lists:append(
                        With_input_tokens,
                        [{<<"output_tokens"/utf8>>, gleam@json:int(V@8)}]
                    );

                none ->
                    With_input_tokens
            end,
            _pipe@2 = gleam@json:object(With_output_tokens),
            gleam@json:to_string(_pipe@2);

        {tool_started, Tool_call} ->
            _pipe@3 = gleam@json:object(
                [{<<"ts"/utf8>>, gleam@json:string(Ts)},
                    {<<"event"/utf8>>,
                        gleam@json:string(<<"tool_started"/utf8>>)},
                    {<<"tool_call"/utf8>>, tool_call_to_json(Tool_call)}]
            ),
            gleam@json:to_string(_pipe@3);

        {tool_executed, Tool_call@1, Result, Duration_ms@1} ->
            _pipe@4 = gleam@json:object(
                [{<<"ts"/utf8>>, gleam@json:string(Ts)},
                    {<<"event"/utf8>>,
                        gleam@json:string(<<"tool_executed"/utf8>>)},
                    {<<"duration_ms"/utf8>>, gleam@json:int(Duration_ms@1)},
                    {<<"tool_call"/utf8>>, tool_call_to_json(Tool_call@1)},
                    {<<"result"/utf8>>, gleam@json:string(Result)}]
            ),
            gleam@json:to_string(_pipe@4);

        {tool_blocked, Tool_call@2, Hook_name, Reason} ->
            _pipe@5 = gleam@json:object(
                [{<<"ts"/utf8>>, gleam@json:string(Ts)},
                    {<<"event"/utf8>>,
                        gleam@json:string(<<"tool_blocked"/utf8>>)},
                    {<<"tool_call"/utf8>>, tool_call_to_json(Tool_call@2)},
                    {<<"hook_name"/utf8>>, gleam@json:string(Hook_name)},
                    {<<"reason"/utf8>>, gleam@json:string(Reason)}]
            ),
            gleam@json:to_string(_pipe@5);

        {hook_acted, Hook_name@1, Hook_point, Action} ->
            _pipe@6 = gleam@json:object(
                [{<<"ts"/utf8>>, gleam@json:string(Ts)},
                    {<<"event"/utf8>>, gleam@json:string(<<"hook_acted"/utf8>>)},
                    {<<"hook_name"/utf8>>, gleam@json:string(Hook_name@1)},
                    {<<"hook_point"/utf8>>,
                        gleam@json:string(hook_to_string(Hook_point))},
                    {<<"action"/utf8>>,
                        gleam@json:object(
                            [{<<"action_type"/utf8>>,
                                    gleam@json:string(erlang:element(2, Action))},
                                {<<"description"/utf8>>,
                                    gleam@json:string(erlang:element(3, Action))}]
                        )}]
            ),
            gleam@json:to_string(_pipe@6);

        {inference_failed, Error, Duration_ms@2, Input_messages@1} ->
            _pipe@7 = gleam@json:object(
                [{<<"ts"/utf8>>, gleam@json:string(Ts)},
                    {<<"event"/utf8>>,
                        gleam@json:string(<<"inference_failed"/utf8>>)},
                    {<<"duration_ms"/utf8>>, gleam@json:int(Duration_ms@2)},
                    {<<"error"/utf8>>, error_to_json(Error)},
                    {<<"input_messages"/utf8>>,
                        gleam@json:array(
                            Input_messages@1,
                            fun message_to_json/1
                        )}]
            ),
            gleam@json:to_string(_pipe@7);

        {session_ended, Reason@1} ->
            _pipe@8 = gleam@json:object(
                [{<<"ts"/utf8>>, gleam@json:string(Ts)},
                    {<<"event"/utf8>>,
                        gleam@json:string(<<"session_ended"/utf8>>)},
                    {<<"reason"/utf8>>, reason_to_json(Reason@1)}]
            ),
            gleam@json:to_string(_pipe@8)
    end.

-file("src/pig/obs/session.gleam", 517).
-spec handle_message(state(), writer_message()) -> gleam@otp@actor:next(state(), writer_message()).
handle_message(State, Message) ->
    case Message of
        {write_event, Event} ->
            Json_str = format_event(Event),
            _ = simplifile:append(
                erlang:element(2, State),
                <<Json_str/binary, "\n"/utf8>>
            ),
            gleam@otp@actor:continue(State);

        {write_event_sync, Event@1, Reply_subject} ->
            Json_str@1 = format_event(Event@1),
            _ = simplifile:append(
                erlang:element(2, State),
                <<Json_str@1/binary, "\n"/utf8>>
            ),
            gleam@erlang@process:send(Reply_subject, nil),
            gleam@otp@actor:continue(State);

        stop ->
            gleam@otp@actor:stop()
    end.

-file("src/pig/obs/session.gleam", 66).
?DOC(" Start a new session writer actor that appends events to the given file.\n").
-spec start(binary()) -> {ok, session_writer()} |
    {error, gleam@otp@actor:start_error()}.
start(Path) ->
    Builder = begin
        _pipe = gleam@otp@actor:new({state, Path}),
        gleam@otp@actor:on_message(_pipe, fun handle_message/2)
    end,
    case gleam@otp@actor:start(Builder) of
        {ok, Started} ->
            {ok, {session_writer, erlang:element(3, Started)}};

        {error, E} ->
            {error, E}
    end.

-file("src/pig/obs/session.gleam", 77).
?DOC(" Stop the session writer actor.\n").
-spec stop(session_writer()) -> nil.
stop(Writer) ->
    {session_writer, Subject} = Writer,
    gleam@erlang@process:send(Subject, stop).

-file("src/pig/obs/session.gleam", 83).
?DOC(" Record a session event. Fire-and-forget: does not block.\n").
-spec record(session_writer(), pig@obs@events:session_event()) -> nil.
record(Writer, Event) ->
    {session_writer, Subject} = Writer,
    gleam@erlang@process:send(Subject, {write_event, Event}).

-file("src/pig/obs/session.gleam", 90).
?DOC(
    " Record a session event synchronously. Blocks until the event is\n"
    " written to disk. Use this in tests for deterministic assertions.\n"
).
-spec record_sync(session_writer(), pig@obs@events:session_event()) -> nil.
record_sync(Writer, Event) ->
    {session_writer, Subject} = Writer,
    Reply_subject = gleam@erlang@process:new_subject(),
    gleam@erlang@process:send(Subject, {write_event_sync, Event, Reply_subject}),
    case gleam@erlang@process:'receive'(Reply_subject, 5000) of
        {ok, _} -> nil;
        _assert_fail ->
            erlang:error(#{gleam_error => let_assert,
                        message => <<"Pattern match failed, no pattern matched the value."/utf8>>,
                        file => <<?FILEPATH/utf8>>,
                        module => <<"pig/obs/session"/utf8>>,
                        function => <<"record_sync"/utf8>>,
                        line => 94,
                        value => _assert_fail,
                        start => 3452,
                        'end' => 3507,
                        pattern_start => 3463,
                        pattern_end => 3468})
    end,
    nil.

-file("src/pig/obs/session.gleam", 226).
?DOC(" Parse a Tool message from a ToolBlocked JSON line.\n").
-spec parse_blocked_tool_message(binary()) -> {ok,
        pig_protocol@message:message()} |
    {error, nil}.
parse_blocked_tool_message(Line) ->
    Id_decoder = gleam@dynamic@decode:at(
        [<<"tool_call"/utf8>>, <<"id"/utf8>>],
        {decoder, fun gleam@dynamic@decode:decode_string/1}
    ),
    Hook_name_decoder = gleam@dynamic@decode:at(
        [<<"hook_name"/utf8>>],
        {decoder, fun gleam@dynamic@decode:decode_string/1}
    ),
    Reason_decoder = gleam@dynamic@decode:at(
        [<<"reason"/utf8>>],
        {decoder, fun gleam@dynamic@decode:decode_string/1}
    ),
    case gleam@json:parse(Line, Id_decoder) of
        {ok, Id} ->
            case {gleam@json:parse(Line, Hook_name_decoder),
                gleam@json:parse(Line, Reason_decoder)} of
                {{ok, Hook_name}, {ok, Reason}} ->
                    {ok,
                        {tool,
                            Id,
                            <<<<<<"Tool blocked by '"/utf8, Hook_name/binary>>/binary,
                                    "': "/utf8>>/binary,
                                Reason/binary>>}};

                {_, _} ->
                    {error, nil}
            end;

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

-file("src/pig/obs/session.gleam", 210).
?DOC(" Parse a Tool message from a ToolExecuted JSON line.\n").
-spec parse_tool_message(binary()) -> {ok, pig_protocol@message:message()} |
    {error, nil}.
parse_tool_message(Line) ->
    Id_decoder = gleam@dynamic@decode:at(
        [<<"tool_call"/utf8>>, <<"id"/utf8>>],
        {decoder, fun gleam@dynamic@decode:decode_string/1}
    ),
    Result_decoder = gleam@dynamic@decode:at(
        [<<"result"/utf8>>],
        {decoder, fun gleam@dynamic@decode:decode_string/1}
    ),
    case gleam@json:parse(Line, Id_decoder) of
        {ok, Id} ->
            case gleam@json:parse(Line, Result_decoder) of
                {ok, Result} ->
                    {ok, {tool, Id, Result}};

                {error, _} ->
                    {error, nil}
            end;

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

-file("src/pig/obs/session.gleam", 182).
?DOC(" Decode the event type from a JSON line.\n").
-spec decode_event_type_str(binary()) -> binary().
decode_event_type_str(Line) ->
    Decoder = gleam@dynamic@decode:at(
        [<<"event"/utf8>>],
        {decoder, fun gleam@dynamic@decode:decode_string/1}
    ),
    case gleam@json:parse(Line, Decoder) of
        {ok, Event_type} ->
            Event_type;

        {error, _} ->
            <<""/utf8>>
    end.

-file("src/pig/obs/session.gleam", 169).
?DOC(" Get lines after the given line.\n").
-spec lines_after(list(binary()), binary()) -> list(binary()).
lines_after(Lines, Target) ->
    case Lines of
        [] ->
            [];

        [L | Rest] ->
            case L =:= Target of
                true ->
                    Rest;

                false ->
                    lines_after(Rest, Target)
            end
    end.

-file("src/pig/obs/session.gleam", 302).
?DOC(" Decode Thinking from JSON.\n").
-spec decode_thinking() -> gleam@dynamic@decode:decoder(gleam@option:option(pig_protocol@message:thinking())).
decode_thinking() ->
    gleam@dynamic@decode:field(
        <<"content"/utf8>>,
        {decoder, fun gleam@dynamic@decode:decode_string/1},
        fun(Content) ->
            gleam@dynamic@decode:success({some, {thinking, Content}})
        end
    ).

-file("src/pig/obs/session.gleam", 308).
?DOC(" Decode a ToolCall from JSON.\n").
-spec decode_tool_call() -> gleam@dynamic@decode:decoder(pig_protocol@message:tool_call()).
decode_tool_call() ->
    gleam@dynamic@decode:field(
        <<"id"/utf8>>,
        {decoder, fun gleam@dynamic@decode:decode_string/1},
        fun(Id) ->
            gleam@dynamic@decode:field(
                <<"name"/utf8>>,
                {decoder, fun gleam@dynamic@decode:decode_string/1},
                fun(Name) ->
                    gleam@dynamic@decode:field(
                        <<"arguments"/utf8>>,
                        {decoder, fun gleam@dynamic@decode:decode_string/1},
                        fun(Arguments_json) ->
                            gleam@dynamic@decode:success(
                                {tool_call, Id, Name, Arguments_json}
                            )
                        end
                    )
                end
            )
        end
    ).

-file("src/pig/obs/session.gleam", 251).
?DOC(" Decode a Message from JSON.\n").
-spec decode_message() -> gleam@dynamic@decode:decoder(pig_protocol@message:message()).
decode_message() ->
    gleam@dynamic@decode:field(
        <<"role"/utf8>>,
        {decoder, fun gleam@dynamic@decode:decode_string/1},
        fun(Role) -> case Role of
                <<"user"/utf8>> ->
                    gleam@dynamic@decode:field(
                        <<"content"/utf8>>,
                        {decoder, fun gleam@dynamic@decode:decode_string/1},
                        fun(Content) ->
                            gleam@dynamic@decode:success({user, Content})
                        end
                    );

                <<"system"/utf8>> ->
                    gleam@dynamic@decode:field(
                        <<"content"/utf8>>,
                        {decoder, fun gleam@dynamic@decode:decode_string/1},
                        fun(Content@1) ->
                            gleam@dynamic@decode:success({system, Content@1})
                        end
                    );

                <<"tool"/utf8>> ->
                    gleam@dynamic@decode:field(
                        <<"tool_call_id"/utf8>>,
                        {decoder, fun gleam@dynamic@decode:decode_string/1},
                        fun(Tool_call_id) ->
                            gleam@dynamic@decode:field(
                                <<"content"/utf8>>,
                                {decoder,
                                    fun gleam@dynamic@decode:decode_string/1},
                                fun(Content@2) ->
                                    gleam@dynamic@decode:success(
                                        {tool, Tool_call_id, Content@2}
                                    )
                                end
                            )
                        end
                    );

                <<"assistant"/utf8>> ->
                    gleam@dynamic@decode:field(
                        <<"content"/utf8>>,
                        {decoder, fun gleam@dynamic@decode:decode_string/1},
                        fun(Content@3) ->
                            gleam@dynamic@decode:field(
                                <<"tool_calls"/utf8>>,
                                gleam@dynamic@decode:list(decode_tool_call()),
                                fun(Tool_calls) ->
                                    gleam@dynamic@decode:optional_field(
                                        <<"thinking"/utf8>>,
                                        none,
                                        decode_thinking(),
                                        fun(Thinking) ->
                                            gleam@dynamic@decode:optional_field(
                                                <<"stop_reason"/utf8>>,
                                                none,
                                                gleam@dynamic@decode:optional(
                                                    pig_protocol@stop_reason:decoder(
                                                        
                                                    )
                                                ),
                                                fun(Stop_reason) ->
                                                    gleam@dynamic@decode:success(
                                                        {assistant,
                                                            Content@3,
                                                            Tool_calls,
                                                            Thinking,
                                                            Stop_reason}
                                                    )
                                                end
                                            )
                                        end
                                    )
                                end
                            )
                        end
                    );

                _ ->
                    gleam@dynamic@decode:failure(
                        {user, <<""/utf8>>},
                        <<"unknown message role: "/utf8, Role/binary>>
                    )
            end end
    ).

-file("src/pig/obs/session.gleam", 191).
?DOC(" Parse input_messages and message from an InferenceCompleted JSON line.\n").
-spec parse_inference_messages(binary()) -> {ok,
        list(pig_protocol@message:message())} |
    {error, replay_error()}.
parse_inference_messages(Line) ->
    Input_decoder = gleam@dynamic@decode:at(
        [<<"input_messages"/utf8>>],
        gleam@dynamic@decode:list(decode_message())
    ),
    case gleam@json:parse(Line, Input_decoder) of
        {ok, Input_msgs} ->
            Msg_decoder = gleam@dynamic@decode:at(
                [<<"message"/utf8>>],
                decode_message()
            ),
            case gleam@json:parse(Line, Msg_decoder) of
                {ok, Response_msg} ->
                    {ok, lists:append(Input_msgs, [Response_msg])};

                {error, _} ->
                    {error,
                        {parse_error,
                            <<"Failed to parse message: "/utf8, Line/binary>>}}
            end;

        {error, _} ->
            {error,
                {parse_error,
                    <<"Failed to parse input_messages: "/utf8, Line/binary>>}}
    end.

-file("src/pig/obs/session.gleam", 158).
?DOC(" Find the last InferenceCompleted line.\n").
-spec find_last_inference_completed(list(binary())) -> gleam@option:option(binary()).
find_last_inference_completed(Lines) ->
    _pipe = Lines,
    gleam@list:fold(
        _pipe,
        none,
        fun(Acc, Line) -> case decode_event_type_str(Line) of
                <<"inference_completed"/utf8>> ->
                    {some, Line};

                _ ->
                    Acc
            end end
    ).

-file("src/pig/obs/session.gleam", 128).
?DOC(" Replay from a list of JSONL lines.\n").
-spec replay_lines(list(binary())) -> {ok, list(pig_protocol@message:message())} |
    {error, replay_error()}.
replay_lines(Lines) ->
    Last_inference = find_last_inference_completed(Lines),
    case Last_inference of
        none ->
            {ok, []};

        {some, Input_messages_json} ->
            case parse_inference_messages(Input_messages_json) of
                {ok, Messages} ->
                    Remaining = lines_after(Lines, Input_messages_json),
                    Tool_msgs = begin
                        _pipe = Remaining,
                        gleam@list:filter_map(
                            _pipe,
                            fun(Line) -> case decode_event_type_str(Line) of
                                    <<"tool_executed"/utf8>> ->
                                        parse_tool_message(Line);

                                    <<"tool_blocked"/utf8>> ->
                                        parse_blocked_tool_message(Line);

                                    _ ->
                                        {error, nil}
                                end end
                        )
                    end,
                    {ok, lists:append(Messages, Tool_msgs)};

                {error, E} ->
                    {error, E}
            end
    end.

-file("src/pig/obs/session.gleam", 111).
?DOC(
    " Replay a JSONL session file and reconstruct the message history.\n"
    "\n"
    " Strategy: find the last InferenceCompleted event. Its input_messages +\n"
    " message give the complete history. For partial sessions (crash mid-loop),\n"
    " also include Tool messages from ToolExecuted events after the last inference.\n"
).
-spec replay(binary()) -> {ok, list(pig_protocol@message:message())} |
    {error, replay_error()}.
replay(Path) ->
    case simplifile:read(Path) of
        {error, E} ->
            {error, {file_error, gleam@string:inspect(E)}};

        {ok, Content} ->
            Lines = begin
                _pipe = Content,
                _pipe@1 = gleam@string:split(_pipe, <<"\n"/utf8>>),
                gleam@list:filter(_pipe@1, fun(L) -> L /= <<""/utf8>> end)
            end,
            case Lines of
                [] ->
                    {ok, []};

                _ ->
                    replay_lines(Lines)
            end
    end.

-file("src/pig/obs/session.gleam", 541).
?DOC(
    " Handle consumer messages (SessionEvent directly, not wrapped in WriterMessage).\n"
    " Used by the supervised consumer actor that receives events from the dispatcher.\n"
).
-spec handle_consumer_message(state(), pig@obs@events:session_event()) -> gleam@otp@actor:next(state(), pig@obs@events:session_event()).
handle_consumer_message(State, Event) ->
    Json_str = format_event(Event),
    case simplifile:append(
        erlang:element(2, State),
        <<Json_str/binary, "\n"/utf8>>
    ) of
        {ok, _} ->
            gleam@otp@actor:continue(State);

        {error, _} ->
            gleam@otp@actor:stop()
    end.

-file("src/pig/obs/session.gleam", 319).
?DOC(
    " Start a session consumer actor that accepts SessionEvent directly.\n"
    " Used by the dispatcher to fan out events. Returns the Subject for registration.\n"
    " This is the consumer version of the actor — it receives SessionEvent directly,\n"
    " not WriterMessage wrappers. Fire-and-forget: does not block.\n"
).
-spec start_consumer(binary()) -> {ok,
        gleam@erlang@process:subject(pig@obs@events:session_event())} |
    {error, gleam@otp@actor:start_error()}.
start_consumer(Path) ->
    Builder = begin
        _pipe = gleam@otp@actor:new({state, Path}),
        gleam@otp@actor:on_message(_pipe, fun handle_consumer_message/2)
    end,
    case gleam@otp@actor:start(Builder) of
        {ok, Started} ->
            {ok, erlang:element(3, Started)};

        {error, E} ->
            {error, E}
    end.

-file("src/pig/obs/session.gleam", 333).
?DOC(
    " Create a supervised session consumer actor for use in a supervision tree.\n"
    " The supervised actor's message type is SessionEvent directly (not WriterMessage).\n"
).
-spec supervised(
    binary(),
    gleam@erlang@process:name(pig@obs@events:session_event())
) -> gleam@otp@supervision:child_specification(nil).
supervised(Path, Name) ->
    gleam@otp@supervision:worker(
        fun() ->
            Builder = begin
                _pipe = gleam@otp@actor:new({state, Path}),
                _pipe@1 = gleam@otp@actor:on_message(
                    _pipe,
                    fun handle_consumer_message/2
                ),
                gleam@otp@actor:named(_pipe@1, Name)
            end,
            case gleam@otp@actor:start(Builder) of
                {ok, Started} ->
                    {ok, {started, erlang:element(2, Started), nil}};

                {error, E} ->
                    {error, E}
            end
        end
    ).