test(streaming): expose world reveal lifecycle

src/AcDream.App/Streaming/WorldRevealReadinessBarrier.cs

@@ -1,5 +1,29 @@
 namespace AcDream.App.Streaming;
 
+/// <summary>
+/// One evaluation of the destination domains guarded by
+/// <see cref="WorldRevealReadinessBarrier"/>. Keeping the individual facts in
+/// the canonical owner lets diagnostics and automation observe readiness
+/// without duplicating (and eventually drifting from) the reveal predicate.
+/// </summary>
+internal readonly record struct WorldRevealReadinessSnapshot(
+    uint DestinationCell,
+    bool IsIndoor,
+    bool IsUnhydratable,
+    int RequiredRenderRadius,
+    bool IsRenderNeighborhoodReady,
+    bool AreCompositeTexturesReady,
+    bool IsCollisionReady)
+{
+    public bool HasDestination => DestinationCell != 0u;
+
+    public bool IsReady => HasDestination
+        && (IsUnhydratable
+            || (IsRenderNeighborhoodReady
+                && AreCompositeTexturesReady
+                && IsCollisionReady));
+}
+
 /// <summary>
 /// Joins the render-publication, texture, and collision domains that must be
 /// complete before the normal world viewport is revealed. Retail keeps
@@ -73,20 +97,46 @@ internal sealed class WorldRevealReadinessBarrier
     /// existing loud forced-placement path can expose the invalid server data.
     /// </summary>
     public bool IsReady(uint destinationCell)
+        => Evaluate(destinationCell).IsReady;
+
+    /// <summary>
+    /// Evaluates each readiness domain once and returns the complete decision.
+    /// Consumers must use this snapshot rather than reimplementing the join.
+    /// </summary>
+    public WorldRevealReadinessSnapshot Evaluate(uint destinationCell)
     {
         if (destinationCell == 0)
-            return false;
-        if (_isSpawnClaimUnhydratable(destinationCell))
-            return true;
+            return default;
 
+        bool isIndoor = IsIndoor(destinationCell);
         int radius = RequiredRenderRadius(destinationCell);
-        if (!_isRenderNeighborhoodReady(destinationCell, radius)
-            || !_areCompositeTexturesReady())
-            return false;
+        if (_isSpawnClaimUnhydratable(destinationCell))
+        {
+            return new WorldRevealReadinessSnapshot(
+                destinationCell,
+                isIndoor,
+                IsUnhydratable: true,
+                radius,
+                IsRenderNeighborhoodReady: false,
+                AreCompositeTexturesReady: false,
+                IsCollisionReady: false);
+        }
 
-        return IsIndoor(destinationCell)
-            ? _isSpawnCellReady(destinationCell)
-            : _isTerrainNeighborhoodReady(destinationCell, radius);
+        bool renderReady = _isRenderNeighborhoodReady(destinationCell, radius);
+        bool compositesReady = renderReady && _areCompositeTexturesReady();
+        bool collisionReady = renderReady && compositesReady
+            && (isIndoor
+                ? _isSpawnCellReady(destinationCell)
+                : _isTerrainNeighborhoodReady(destinationCell, radius));
+
+        return new WorldRevealReadinessSnapshot(
+            destinationCell,
+            isIndoor,
+            IsUnhydratable: false,
+            radius,
+            renderReady,
+            compositesReady,
+            collisionReady);
     }
 
     private static int RequiredRenderRadius(uint destinationCell) =>