--liquibase formatted sql
-- PANELS · core · edición de préstamos y estado de cuenta

--changeset panel:core-045a-fn-loan-update splitStatements:false
CREATE OR REPLACE FUNCTION core.fn_loan_update(payload jsonb)
RETURNS jsonb
LANGUAGE plpgsql
SECURITY INVOKER
SET search_path = core
AS $$
DECLARE
  v_id bigint := NULLIF(payload->>'id', '')::bigint;
  v_loan loans%ROWTYPE;
  v_paid numeric;
  v_n integer;
  v_delivered numeric;
  v_pct numeric;
  v_comm numeric;
  v_balance numeric;
  v_weekly numeric;
  v_note text;
BEGIN
  IF v_id IS NULL THEN
    RETURN core.rpc_err('VALIDATION', 'fn_loan_update: id es obligatorio',
      jsonb_build_object('fn', 'fn_loan_update', 'field', 'id'));
  END IF;
  SELECT * INTO v_loan FROM loans WHERE id = v_id;
  IF NOT FOUND THEN
    RETURN core.rpc_err('NOT_FOUND', format('fn_loan_update: préstamo id=%s no encontrado', v_id),
      jsonb_build_object('fn', 'fn_loan_update', 'id', v_id));
  END IF;
  SELECT COALESCE(SUM(amount), 0), COUNT(*)::integer INTO v_paid, v_n FROM loan_payments WHERE loan_id = v_id;
  v_note := CASE WHEN payload ? 'note' THEN nullif(btrim(payload->>'note'), '') ELSE v_loan.note END;
  IF v_n > 0 THEN
    v_weekly := COALESCE((payload->>'weekly_payment')::numeric, v_loan.weekly_payment);
    UPDATE loans SET note = v_note, weekly_payment = core.round_money(v_weekly) WHERE id = v_id;
  ELSE
    v_delivered := core.round_money(COALESCE((payload->>'delivered')::numeric, v_loan.delivered));
    IF v_delivered <= 0 THEN
      RETURN core.rpc_err('VALIDATION', 'fn_loan_update: el monto entregado debe ser mayor a cero',
        jsonb_build_object('fn', 'fn_loan_update', 'field', 'delivered'));
    END IF;
    v_pct := COALESCE((payload->>'commission_pct')::numeric, v_loan.commission_pct);
    v_comm := core._payroll_commission_amount(v_delivered, v_pct);
    v_balance := core.round_money(v_delivered + v_comm);
    v_weekly := COALESCE((payload->>'weekly_payment')::numeric, core.round_money(v_balance / GREATEST(v_loan.installments_n, 1)));
    UPDATE loans SET
      amount = v_delivered,
      delivered = v_delivered,
      commission_pct = v_pct,
      commission_amount = v_comm,
      balance = v_balance,
      weekly_payment = core.round_money(v_weekly),
      note = v_note,
      plan = COALESCE(NULLIF(btrim(payload->>'plan'), ''), plan),
      installments_n = COALESCE(NULLIF(payload->>'installments_n', '')::integer, installments_n),
      first_due = COALESCE(NULLIF(payload->>'first_due', '')::date, first_due)
    WHERE id = v_id;
  END IF;
  UPDATE loans SET balance = core.round_money(delivered + commission_amount - v_paid) WHERE id = v_id;
  RETURN core.rpc_ok(
    jsonb_build_object('id', v_id),
    format('Préstamo id=%s actualizado', v_id),
    jsonb_build_object('fn', 'fn_loan_update', 'id', v_id, 'payments', v_n)
  );
EXCEPTION WHEN OTHERS THEN
  RETURN core.rpc_from_exception('fn_loan_update', SQLSTATE, SQLERRM);
END;
$$;

--changeset panel:core-045b-fn-loan-statement splitStatements:false
CREATE OR REPLACE FUNCTION core.fn_loan_statement(payload jsonb)
RETURNS jsonb
LANGUAGE plpgsql
SECURITY INVOKER
SET search_path = core
AS $$
DECLARE
  v_id bigint := NULLIF(payload->>'id', '')::bigint;
  v_loan jsonb;
  v_payments jsonb;
  v_paid numeric;
BEGIN
  SELECT to_jsonb(l) INTO v_loan FROM loans l WHERE l.id = v_id;
  IF v_loan IS NULL THEN
    RETURN core.rpc_err('NOT_FOUND', 'Préstamo no encontrado',
      jsonb_build_object('fn', 'fn_loan_statement', 'id', v_id));
  END IF;
  SELECT COALESCE(SUM(amount), 0) INTO v_paid FROM loan_payments WHERE loan_id = v_id;
  UPDATE loans SET balance = core.round_money(
    (v_loan->>'delivered')::numeric + (v_loan->>'commission_amount')::numeric - v_paid
  ) WHERE id = v_id;
  SELECT to_jsonb(l) INTO v_loan FROM loans l WHERE l.id = v_id;
  SELECT COALESCE(jsonb_agg(to_jsonb(x) ORDER BY x.created_at, x.id), '[]'::jsonb)
    INTO v_payments
    FROM (
      SELECT p.id, p.amount, p.label, p.installment_n, p.created_at, wk.week_start, wk.week_end
        FROM loan_payments p
        JOIN payroll_weeks wk ON wk.id = p.week_id
       WHERE p.loan_id = v_id
    ) x;
  RETURN core.rpc_ok(
    jsonb_build_object('loan', v_loan, 'payments', v_payments, 'paid', v_paid),
    format('Estado de cuenta del préstamo id=%s', v_id),
    jsonb_build_object('fn', 'fn_loan_statement', 'id', v_id)
  );
EXCEPTION WHEN OTHERS THEN
  RETURN core.rpc_from_exception('fn_loan_statement', SQLSTATE, SQLERRM);
END;
$$;

--changeset panel:core-045c-grants endDelimiter:; splitStatements:true
GRANT EXECUTE ON FUNCTION core.fn_loan_update(jsonb) TO panels_core_app;
GRANT EXECUTE ON FUNCTION core.fn_loan_statement(jsonb) TO panels_core_app;