%%%-------------------------------------------------------------------
%%% @doc Escalation — assess complexity and route cases to panels.
%%%
%%% Architecture §3.2:
%%% assess(Case) determines complexity, route/2 convenes the panel.
%%%
%%% Panel sizes from halakha:
%%%   simple   -> 1 judge  (individual matters)
%%%   monetary -> 3 judges (dinei mamonot)
%%%   capital  -> 23 judges (dinei nefashot)
%%%   novel    -> 71 judges (Sanhedrin Gedolah)
%%% @end
%%%-------------------------------------------------------------------
-module(escalation).

-behaviour(gen_server).

-include("sanhedrin.hrl").

%% API
-export([start_link/0, submit_case/1, assess/1]).

%% gen_server callbacks
-export([init/1, handle_call/3, handle_cast/2, handle_info/2]).

-define(SERVER, ?MODULE).

-record(state, {
    active_cases = #{} :: map(),  %% case_ref => panel_pid
    case_count = 0     :: non_neg_integer()
}).

%%====================================================================
%% API
%%====================================================================

start_link() ->
    gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).

%% @doc Submit a case for deliberation.
%% Returns {ok, CaseRef} or {error, Reason}.
-spec submit_case(#sanhedrin_case{}) -> {ok, binary()} | {error, term()}.
submit_case(Case) ->
    gen_server:call(?SERVER, {submit_case, Case}, 30000).

%% @doc Assess complexity of a case. Pure function.
-spec assess(#sanhedrin_case{}) -> {panel, pos_integer()}.
assess(#sanhedrin_case{complexity = simple})   -> {panel, ?PANEL_SIMPLE};
assess(#sanhedrin_case{complexity = monetary}) -> {panel, ?PANEL_MONETARY};
assess(#sanhedrin_case{complexity = capital})  -> {panel, ?PANEL_CAPITAL};
assess(#sanhedrin_case{complexity = novel})    -> {panel, ?PANEL_NOVEL}.

%%====================================================================
%% gen_server callbacks
%%====================================================================

init([]) ->
    {ok, #state{}}.

handle_call({submit_case, Case}, _From, State) ->
    %% First check halt conditions
    case halt_monitor:check_case(Case) of
        clear ->
            %% Assess complexity and route
            {panel, Size} = assess(Case),
            Timeout = timeout_for(Case#sanhedrin_case.complexity),
            case panel_sup:start_panel(Case, Size) of
                {ok, PanelPid} ->
                    %% Start deliberation asynchronously
                    panel:deliberate_async(PanelPid, Timeout),
                    NewActive = maps:put(
                        Case#sanhedrin_case.case_ref,
                        PanelPid,
                        State#state.active_cases
                    ),
                    {reply,
                     {ok, Case#sanhedrin_case.case_ref},
                     State#state{
                         active_cases = NewActive,
                         case_count = State#state.case_count + 1
                     }};
                {error, Reason} ->
                    {reply, {error, {panel_start_failed, Reason}}, State}
            end;
        {halt, Condition, Reason} ->
            {reply, {error, {halted, Condition, Reason}}, State}
    end;

handle_call(_Request, _From, State) ->
    {reply, {error, unknown_request}, State}.

handle_cast(_Msg, State) ->
    {noreply, State}.

handle_info({panel_decided, CaseRef, Decision}, State) ->
    %% Panel has reached a decision — store via clerk
    clerk:store_decision(CaseRef, Decision),
    NewActive = maps:remove(CaseRef, State#state.active_cases),
    {noreply, State#state{active_cases = NewActive}};

handle_info(_Info, State) ->
    {noreply, State}.

%%====================================================================
%% Internal
%%====================================================================

timeout_for(simple)   -> ?TIMEOUT_SIMPLE;
timeout_for(monetary) -> ?TIMEOUT_MONETARY;
timeout_for(capital)  -> ?TIMEOUT_CAPITAL;
timeout_for(novel)    -> ?TIMEOUT_NOVEL.