using Google.Protobuf;
using Google.Protobuf.WellKnownTypes;
using ScadaLink.Communication.Grpc;

namespace ScadaLink.Communication.Tests.Protos;

/// <summary>
/// Wire-format round-trip tests for the Audit Log (#23) M6 reconciliation
/// pull proto messages (<see cref="PullAuditEventsRequest"/>,
/// <see cref="PullAuditEventsResponse"/>). Locks the additive contract the
/// central→site reconciliation puller depends on.
/// </summary>
public class PullAuditEventsProtoTests
{
    private static AuditEventDto NewAuditDto(Guid? id = null) => new()
    {
        EventId = (id ?? Guid.NewGuid()).ToString(),
        OccurredAtUtc = Timestamp.FromDateTimeOffset(
            new DateTimeOffset(2026, 5, 20, 10, 15, 30, 123, TimeSpan.Zero)),
        Channel = "ApiOutbound",
        Kind = "ApiCall",
        Status = "Delivered",
        SourceSiteId = "site-1",
    };

    [Fact]
    public void PullAuditEventsRequest_RoundTrip()
    {
        var sinceUtc = Timestamp.FromDateTimeOffset(
            new DateTimeOffset(2026, 5, 20, 9, 0, 0, TimeSpan.Zero));

        var original = new PullAuditEventsRequest
        {
            SinceUtc = sinceUtc,
            BatchSize = 250,
        };

        var bytes = original.ToByteArray();
        var deserialized = PullAuditEventsRequest.Parser.ParseFrom(bytes);

        Assert.Equal(sinceUtc, deserialized.SinceUtc);
        Assert.Equal(250, deserialized.BatchSize);
    }

    [Fact]
    public void PullAuditEventsResponse_RoundTrip_WithEvents_And_MoreAvailable()
    {
        var dtos = Enumerable.Range(0, 4).Select(_ => NewAuditDto()).ToList();

        var original = new PullAuditEventsResponse
        {
            MoreAvailable = true,
        };
        original.Events.AddRange(dtos);

        var bytes = original.ToByteArray();
        var deserialized = PullAuditEventsResponse.Parser.ParseFrom(bytes);

        Assert.True(deserialized.MoreAvailable);
        Assert.Equal(4, deserialized.Events.Count);
        for (int i = 0; i < dtos.Count; i++)
        {
            Assert.Equal(dtos[i].EventId, deserialized.Events[i].EventId);
            Assert.Equal(dtos[i].Status, deserialized.Events[i].Status);
            Assert.Equal(dtos[i].SourceSiteId, deserialized.Events[i].SourceSiteId);
            Assert.Equal(dtos[i].OccurredAtUtc, deserialized.Events[i].OccurredAtUtc);
        }
    }

    [Fact]
    public void PullAuditEventsResponse_Empty_Yields_EmptyEvents()
    {
        var original = new PullAuditEventsResponse();
        Assert.Empty(original.Events);
        Assert.False(original.MoreAvailable);

        var bytes = original.ToByteArray();
        var deserialized = PullAuditEventsResponse.Parser.ParseFrom(bytes);

        Assert.Empty(deserialized.Events);
        Assert.False(deserialized.MoreAvailable);
    }
}