using Theriapolis.Core.World.Generation;
using Theriapolis.Core.World.Generation.Stages;
using Xunit;

namespace Theriapolis.Tests.Worldgen;

/// <summary>
/// Addendum A §1: the coastline must have organic noise-based shape across a
/// range of seeds after the BorderDistortionGen stage runs.
///
/// The validator counts maximal runs of consecutive border tiles in four line
/// orientations (horizontal, vertical, both diagonals).  Any run longer than
/// <see cref="BorderDistortionGenStage.MaxAllowedRunLength"/> tiles is a
/// violation — this catches both axis-aligned and diagonal ruler-straight
/// coasts, which the previous cardinal-only 3-run detector missed.
/// </summary>
public sealed class BorderOrganicsTests : IClassFixture<WorldCache>
{
    private readonly WorldCache _cache;

    public BorderOrganicsTests(WorldCache cache) => _cache = cache;

    private int ViolationsForSeed(ulong seed)
    {
        var ctx = _cache.Get(seed);
        return BorderDistortionGenStage.CountStraightViolations(ctx);
    }

    [Fact]
    public void Seed_CAFEBABE_HasZeroStraightViolations()
    {
        Assert.Equal(0, ViolationsForSeed(0xCAFEBABEUL));
    }

    [Theory]
    [InlineData(1UL)]
    [InlineData(42UL)]
    [InlineData(999UL)]
    [InlineData(0xDEAD_BEEFUL)]
    [InlineData(0x1234_5678UL)]
    [InlineData(0xABCD_EF01UL)]
    [InlineData(7777777UL)]
    [InlineData(0xFF00_FF00UL)]
    [InlineData(314159265UL)]
    [InlineData(271828182UL)]
    public void TenSeeds_HaveZeroStraightViolations(ulong seed)
    {
        Assert.Equal(0, ViolationsForSeed(seed));
    }
}