import 'package:etm_powersync_app/services/energy_ratios.dart';
import 'package:flutter_test/flutter_test.dart';

/// Couvre l'interim ratios (§2.1) : dérivation par Δ cumuls, reseed (jour /
/// non-monotone), garde-fous (n/a, pas de NaN, clamp), formule autoconso band.
void main() {
  final d1 = DateTime(2026, 6, 28, 12);
  final d1bis = DateTime(2026, 6, 28, 13);
  final d2 = DateTime(2026, 6, 29, 9);

  test('1er échantillon : Δ=0 → n/a (null), jamais NaN', () {
    final s = EnergyRatiosInterim();
    final r = s.compute(
        totalProduction: 10,
        totalReturn: 2,
        totalConsumption: 8,
        totalAcquisition: 3,
        now: d1);
    expect(r.autoconsommation, isNull);
    expect(r.autonomie, isNull);
  });

  test('Δ cumuls même jour → ratios déterministes, bornés [0,100]', () {
    final s = EnergyRatiosInterim();
    s.compute(
        totalProduction: 10,
        totalReturn: 2,
        totalConsumption: 8,
        totalAcquisition: 3,
        now: d1); // baseline
    final r = s.compute(
        totalProduction: 20, // Δprod=10
        totalReturn: 4, // Δret=2  → autoconso=(10-2)/10=80
        totalConsumption: 18, // Δcons=10
        totalAcquisition: 8, // Δacq=5  → autonomie=(10-5)/10=50
        now: d1bis);
    expect(r.autoconsommation, closeTo(80, 0.001));
    expect(r.autonomie, closeTo(50, 0.001));
  });

  test('nouveau jour local → reseed baseline (Δ repart de 0)', () {
    final s = EnergyRatiosInterim();
    s.compute(
        totalProduction: 10, totalReturn: 2, totalConsumption: 8,
        totalAcquisition: 3, now: d1);
    final r = s.compute(
        totalProduction: 99, totalReturn: 9, totalConsumption: 99,
        totalAcquisition: 9, now: d2); // jour différent → reseed → Δ=0
    expect(r.autoconsommation, isNull);
    expect(r.autonomie, isNull);
  });

  test('compteur non monotone (Δ<0) → reseed, jamais de ratio négatif', () {
    final s = EnergyRatiosInterim();
    s.compute(
        totalProduction: 100, totalReturn: 10, totalConsumption: 80,
        totalAcquisition: 5, now: d1); // baseline haute
    // restart nymead : cumuls repartent bas → non monotone → reseed
    final r = s.compute(
        totalProduction: 5, totalReturn: 1, totalConsumption: 4,
        totalAcquisition: 1, now: d1bis);
    expect(r.autoconsommation, anyOf(isNull, greaterThanOrEqualTo(0)));
    expect(r.autonomie, anyOf(isNull, greaterThanOrEqualTo(0)));
  });

  test('dénominateur nul (nuit sans prod) → n/a, pas de NaN', () {
    final s = EnergyRatiosInterim();
    s.compute(
        totalProduction: 10, totalReturn: 2, totalConsumption: 8,
        totalAcquisition: 3, now: d1);
    final r = s.compute(
        totalProduction: 10, // Δprod=0 → autoconso n/a
        totalReturn: 2,
        totalConsumption: 8, // Δcons=0 → autonomie n/a
        totalAcquisition: 3,
        now: d1bis);
    expect(r.autoconsommation, isNull);
    expect(r.autonomie, isNull);
  });

  test('selfConsumptionPower (§2.2) : net-signé, sans abs', () {
    // export (acq<0) retranché de la production
    expect(EnergyRatiosInterim.selfConsumptionPower(4869, -231),
        closeTo(4638, 0.001));
    // import (acq>0) → tout est autoconsommé
    expect(EnergyRatiosInterim.selfConsumptionPower(2000, 500), 2000);
    // export > production → borné à 0 (pas de négatif)
    expect(EnergyRatiosInterim.selfConsumptionPower(100, -300), 0);
  });
}