using FluentAssertions;
using ProposalSystem.Application.Common;
using Xunit;

namespace ProposalSystem.Tests.Common;

public class RowVersionCodecTests
{
    [Theory(DisplayName = "Encode/TryDecode round-trips")]
    [InlineData(1L)]
    [InlineData(2L)]
    [InlineData(long.MaxValue)]
    public void RoundTrips(long version)
    {
        var token = RowVersionCodec.Encode(version);

        RowVersionCodec.TryDecode(token, out var decoded).Should().BeTrue();
        decoded.Should().Be(version);
    }

    [Fact(DisplayName = "Version 1 encodes to the SHOC-style opaque token")]
    public void EncodesOpaqueBase64()
    {
        RowVersionCodec.Encode(1).Should().Be("AAAAAAAAAAE=");
    }

    [Theory(DisplayName = "TryDecode rejects missing/malformed/wrong-length tokens")]
    [InlineData(null)]
    [InlineData("")]
    [InlineData("not base64!!")]
    [InlineData("AAA=")] // valid base64 but not 8 bytes
    [InlineData("AAAAAAAAAAAAAAAAAAAAAA==")] // 16 bytes
    public void RejectsInvalid(string? token)
    {
        RowVersionCodec.TryDecode(token, out _).Should().BeFalse();
    }
}