using System;
using System.Text;
using FluentAssertions;
using StellaOps.Replay.Core;
using Xunit;

namespace StellaOps.Replay.Core.Tests;

public sealed class DsseEnvelopeTests
{
    [Fact]
    public void BuildUnsigned_ProducesCanonicalPayload()
    {
        var manifest = new ReplayManifest
        {
            Scan = new ReplayScanMetadata
            {
                Id = "scan-123",
                Time = DateTimeOffset.UnixEpoch
            }
        };

        var envelope = DssePayloadBuilder.BuildUnsigned(manifest);

        envelope.PayloadType.Should().Be(DssePayloadBuilder.ReplayPayloadType);
        envelope.Signatures.Should().BeEmpty();

        var payload = Convert.FromBase64String(envelope.Payload);
        var json = Encoding.UTF8.GetString(payload);

        json.Should().Be("{\"reachability\":{\"graphs\":[],\"runtimeTraces\":[]},\"scan\":{\"id\":\"scan-123\",\"time\":\"1970-01-01T00:00:00+00:00\"},\"schemaVersion\":\"1.0\"}");
        envelope.DigestSha256.Should().Be(DeterministicHash.Sha256Hex(payload));
    }
}