-- Choice identity is the persisted focus UUID plus the inference revision.
-- Derived question_id is an audit label only. A card the server just returned
-- must not 409 stale_question while the Case revision is unchanged.
-- Business schema only; do not copy into frontend/db/migrations (BUG-127 / BUG-144).

begin;

create or replace function public.apply_agentic_rectification_choice_action(
  p_user_id uuid,
  p_case_id uuid,
  p_action_id uuid,
  p_question_id text,
  p_option_id text,
  p_expected_revision integer,
  p_focus_id uuid,
  p_focus_status text,
  p_source_quote text,
  p_derived_context jsonb,
  p_narration text,
  p_inference jsonb
)
returns jsonb
language plpgsql
security definer
set search_path = ''
as $$
declare
  v_case public.agentic_rectification_cases%rowtype;
  v_focus public.agentic_rectification_conversation_focuses%rowtype;
  v_existing public.agentic_rectification_choice_actions%rowtype;
  v_transition jsonb;
  v_focus_result jsonb;
  v_receipt jsonb;
  v_id uuid;
  v_probe_id text;
  v_question_id text;
begin
  if p_user_id is null or p_case_id is null or p_action_id is null
    or p_option_id is null or p_option_id not in ('A', 'B', 'C', 'D', 'stop')
    or p_expected_revision is null or p_expected_revision < 0
    or p_focus_id is null
    or p_focus_status is null or p_focus_status not in ('resolved', 'declined', 'skipped')
    or p_derived_context is null or jsonb_typeof(p_derived_context) <> 'object'
    or (p_inference is not null and jsonb_typeof(p_inference) <> 'object') then
    raise exception 'agentic_rectification_invalid_input' using errcode = 'P0001';
  end if;

  select * into v_case
  from public.agentic_rectification_cases
  where id = p_case_id and user_id = p_user_id
  for update;
  if not found then
    raise exception 'agentic_rectification_case_not_found' using errcode = 'P0001';
  end if;
  if v_case.status in ('confirmed', 'closed', 'abandoned', 'superseded') then
    raise exception 'agentic_rectification_case_terminal' using errcode = 'P0001';
  end if;

  select * into v_existing
  from public.agentic_rectification_choice_actions
  where case_id = p_case_id
    and action_id = p_action_id;
  if found then
    return jsonb_set(v_existing.receipt, '{idempotent}', 'true'::jsonb, true);
  end if;

  select * into v_focus
  from public.agentic_rectification_conversation_focuses
  where id = p_focus_id and case_id = p_case_id
  for update;
  if not found then
    raise exception 'agentic_rectification_focus_not_found' using errcode = 'P0001';
  end if;
  if v_focus.status is distinct from 'active' then
    raise exception 'agentic_rectification_stale_question' using errcode = 'P0001';
  end if;

  v_question_id := coalesce(nullif(btrim(coalesce(p_question_id, '')), ''), v_focus.question_id);

  insert into public.agentic_rectification_choice_actions (
    case_id, action_id, question_id, probe_id, option_id, expected_revision,
    status, answer_class, source_quote, derived_context, focus_id, narration, receipt
  ) values (
    p_case_id, p_action_id, v_question_id,
    nullif(btrim(coalesce(p_inference ->> 'probe_id', p_derived_context ->> 'derivedFromProbeId', '')), ''),
    p_option_id, p_expected_revision, 'received',
    nullif(btrim(coalesce(p_inference ->> 'answer_class', p_derived_context ->> 'answerClass', '')), ''),
    nullif(btrim(coalesce(p_source_quote, '')), ''),
    p_derived_context, p_focus_id, nullif(btrim(coalesce(p_narration, '')), ''),
    jsonb_build_object('status', 'received')
  )
  returning * into v_existing;

  v_transition := null;
  if p_inference is not null then
    v_transition := public.append_agentic_rectification_inference_transition(
      p_user_id,
      p_case_id,
      coalesce((p_inference ->> 'expected_revision')::integer, p_expected_revision),
      p_inference ->> 'probe_id',
      p_inference ->> 'open_probe_id',
      p_inference ->> 'semantic_key',
      p_inference ->> 'candidate_split_hash',
      p_inference ->> 'answer_class',
      p_inference ->> 'raw_answer',
      p_inference -> 'inference_state',
      coalesce(p_inference -> 'posterior_before', '{}'::jsonb),
      coalesce(p_inference -> 'posterior_after', '{}'::jsonb),
      coalesce(p_inference -> 'score_deltas', '{}'::jsonb),
      p_inference ->> 'decision_state_fingerprint',
      p_inference ->> 'reason',
      p_inference ->> 'idempotency_key',
      p_inference ->> 'candidate_set_id'
    );
  end if;

  v_focus_result := public.resolve_agentic_rectification_conversation_focus(
    p_user_id, p_case_id, p_focus_id, p_focus_status, null
  );

  v_probe_id := coalesce(
    v_transition ->> 'probe_id',
    p_inference ->> 'probe_id',
    p_derived_context ->> 'derivedFromProbeId'
  );
  v_receipt := jsonb_build_object(
    'action_id', p_action_id,
    'status', 'applied',
    'idempotent', false,
    'question_id', v_question_id,
    'option_id', p_option_id,
    'probe_id', to_jsonb(v_probe_id),
    'revision', coalesce((v_transition ->> 'revision')::integer, p_expected_revision),
    'focus_id', v_focus_result -> 'focus_id',
    'focus_status', v_focus_result -> 'status',
    'transition_id', v_transition -> 'transition_id',
    'source_quote', to_jsonb(nullif(btrim(coalesce(p_source_quote, '')), '')),
    'derived_context', p_derived_context,
    'narration', to_jsonb(nullif(btrim(coalesce(p_narration, '')), ''))
  );

  update public.agentic_rectification_choice_actions
  set status = 'applied',
      probe_id = v_probe_id,
      transition_id = nullif(v_transition ->> 'transition_id', '')::uuid,
      receipt = v_receipt,
      updated_at = pg_catalog.now()
  where id = v_existing.id
  returning id into v_id;

  update public.agentic_rectification_cases
  set last_activity_at = pg_catalog.now(),
      updated_at = pg_catalog.now()
  where id = p_case_id;

  return v_receipt;
exception
  when unique_violation then
    select * into v_existing
    from public.agentic_rectification_choice_actions
    where case_id = p_case_id
      and action_id = p_action_id;
    if found then
      return jsonb_set(v_existing.receipt, '{idempotent}', 'true'::jsonb, true);
    end if;
    raise;
end;
$$;

revoke all on function public.apply_agentic_rectification_choice_action(
  uuid, uuid, uuid, text, text, integer, uuid, text, text, jsonb, text, jsonb
) from public, anon, authenticated;
grant execute on function public.apply_agentic_rectification_choice_action(
  uuid, uuid, uuid, text, text, integer, uuid, text, text, jsonb, text, jsonb
) to service_role;

commit;