using MeterVault.Core.Domain;
using MeterVault.Core.Normalization;
using MeterVault.Infrastructure.Import;
using static MeterVault.Integration.Tests.Reconciliation.ReconciliationSupport;

namespace MeterVault.Integration.Tests.Reconciliation;

/// <summary>
/// Gap splitting apportions a long unread stretch across the months it covers. The reference sheets
/// are read monthly and must never trigger it, or their months would silently shift and the whole
/// golden-fixture oracle (SDD §13) would be measuring the splitter instead of the normalizer.
/// </summary>
/// <remarks>
/// The reconciliation suites already compare month by month, so a spurious split would surface there
/// as a numeric failure. This asserts the mechanism directly instead of relying on that side effect:
/// it proves the rule was evaluated against real fixture cadence and declined to fire, rather than
/// the fixtures simply having no gaps to find.
/// </remarks>
public sealed class GapSplittingIsInertOnFixturesTests
{
    [Theory]
    [InlineData(ReferenceProfiles.Haus, MeterMode.CumulativeCounter)]
    [InlineData(ReferenceProfiles.Netz, MeterMode.CumulativeCounter)]
    [InlineData(ReferenceProfiles.Auto, MeterMode.CumulativeCounter)]
    [InlineData(ReferenceProfiles.Solar1, MeterMode.GenerationCounter)]
    [InlineData(ReferenceProfiles.Solar2, MeterMode.GenerationCounter)]
    public void Electricity_meters_produce_exactly_one_row_per_reading(int meterId, MeterMode mode)
    {
        var staged = Stage(ReferenceProfiles.Electricity(), Electricity);
        var readings = staged.Readings.Count(r => r.MeterId == meterId);

        var computed = Normalize(staged, new MeterConfig { MeterId = meterId, Mode = mode, Unit = "kWh" });

        Assert.True(readings > 20, $"meter {meterId}: expected a real series, got {readings} readings.");
        Assert.Equal(readings, computed.Count);
    }

    [Fact]
    public void No_fixture_interval_is_long_enough_to_split()
    {
        var staged = Stage(ReferenceProfiles.Electricity(), Electricity);

        foreach (var group in staged.Readings.GroupBy(r => r.MeterId))
        {
            var times = group.Select(r => r.Time).OrderBy(t => t).ToList();
            for (var i = 1; i < times.Count; i++)
            {
                Assert.False(
                    GapAttribution.ShouldSplit(times[i - 1], times[i]),
                    $"meter {group.Key}: {times[i - 1]:yyyy-MM-dd} → {times[i]:yyyy-MM-dd} would be split.");
            }
        }
    }
}