using System.Reflection;
using AcDream.App.Rendering;
using AcDream.App.Tests.Architecture;

namespace AcDream.App.Tests.Rendering;

public sealed class RetailPViewRendererTests
{
    /// <summary>
    /// S4-c2 fix round 1 addendum (A1): retail's LandscapeFlush
    /// (<c>PView::DrawCells</c> @0x005a4840's own <c>FlushAlphaList(0f)</c>
    /// @0x005a4872) only ever fires on an INTERIOR PView, strictly inside
    /// <c>if (outside_view.view_count &gt; 0)</c> — an outdoor root never
    /// reaches it (terrace-edge's capture: zero <c>005a4877</c> FL lines).
    /// In production the interior case reaches
    /// <see cref="RetailPViewPassExecutor.FlushLandscapeAlpha"/> through the
    /// walk driver's LandscapeFlush leaf (<c>FlushWalkLandscape</c>, a
    /// SEPARATE method the driver calls during <c>Replay</c>) — never as a
    /// direct call compiled into <see cref="RetailPViewRenderer.DrawInside"/>'s
    /// own body. The outdoor-root direct call that used to sit inline here
    /// (mislabelled LandscapeFlush) is deleted; retail's real outdoor-root
    /// drains are the <c>DrawBlock</c> 0.75 valve (already wired via
    /// <c>WalkFrameEventKind.SortCellExit</c>) and
    /// <c>SmartBox::RenderNormalMode</c>'s pass-end flush
    /// (<see cref="RetailAlphaQueue.EndFrame"/>, called from
    /// <c>WorldSceneRenderer.CompleteWorldFrame</c>).
    ///
    /// <para>Mutation check: reverting the deletion (restoring
    /// <c>if (ctx.RootCell.IsOutdoorNode) passes.FlushLandscapeAlpha();</c>)
    /// reintroduces a direct call to
    /// <see cref="RetailPViewPassExecutor.FlushLandscapeAlpha"/> inside
    /// <see cref="RetailPViewRenderer.DrawInside"/>'s compiled body — the
    /// <c>Assert.DoesNotContain</c> below fails against that mutation.</para>
    /// </summary>
    [Fact]
    public void DrawInside_NeverCallsFlushLandscapeAlphaDirectly()
    {
        MethodInfo drawInside = typeof(RetailPViewRenderer).GetMethod(
            "DrawInside",
            BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public)!;
        IReadOnlyList<CompiledCall> calls = CompiledCallGraph.Read(drawInside);

        Assert.DoesNotContain(
            calls,
            call => call.Target.DeclaringType == typeof(RetailPViewPassExecutor)
                && call.Target.Name == nameof(RetailPViewPassExecutor.FlushLandscapeAlpha));

        // The interior-cell unattached-emitter draw beside the deleted call
        // must remain — this pin only removes the mislabelled flush, not
        // the particle submission next to it.
        Assert.Contains(
            calls,
            call => call.Target.DeclaringType == typeof(RetailPViewPassExecutor)
                && call.Target.Name == nameof(RetailPViewPassExecutor.DrawUnattachedSceneParticles));
    }
}