Use reflection to discover cascading parameters in ComponentRenderer

src/ScissorHands.Web/Renderers/ComponentRenderer.cs

@@ -1,8 +1,12 @@
+using System.Reflection;
+
 using Microsoft.AspNetCore.Components;
 using Microsoft.AspNetCore.Components.Web;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 
+using ScissorHands.Theme;
+
 namespace ScissorHands.Web.Renderers;
 
 /// <summary>
@@ -15,6 +19,39 @@ public sealed class ComponentRenderer(IServiceScopeFactory scopeFactory, ILogger
     private readonly IServiceScopeFactory _scopeFactory = scopeFactory ?? throw new ArgumentNullException(nameof(scopeFactory));
     private readonly ILoggerFactory _loggerFactory = loggerFactory ?? throw new ArgumentNullException(nameof(loggerFactory));
 
+    // Lazy initialization of cascading parameter names discovered via reflection
+    private static readonly Lazy<HashSet<string>> _cascadingParameterNames = new(() =>
+    {
+        var parameterNames = new HashSet<string>(StringComparer.Ordinal);
+
+        // Discover all types in the ScissorHands.Theme assembly that have cascading parameters
+        var themeAssembly = typeof(PageViewBase).Assembly;
+
+        try
+        {
+            var allTypes = themeAssembly.GetExportedTypes();
+
+            foreach (var type in allTypes)
+            {
+                // Find all properties with CascadingParameter attribute
+                var cascadingProperties = type.GetProperties(BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly)
+                    .Where(p => p.GetCustomAttribute<CascadingParameterAttribute>() is not null);
+
+                foreach (var property in cascadingProperties)
+                {
+                    parameterNames.Add(property.Name);
+                }
+            }
+        }
+        catch (ReflectionTypeLoadException)
+        {
+            // If type loading fails, fall back to empty set
+            // This should not happen in normal operation, but provides safety
+        }
+
+        return parameterNames;
+    });
+
     /// <inheritdoc />
     public async Task<string> RenderAsync<TComponent>(Type layoutType, IDictionary<string, object?> parameters, CancellationToken cancellationToken = default)
         where TComponent : IComponent
@@ -32,18 +69,9 @@ public async Task<string> RenderAsync<TComponent>(Type layoutType, IDictionary<s
                 builder.OpenComponent<TComponent>(0);
                 var seq = 1;
 
-                var cascadingKeys = new HashSet<string>(StringComparer.Ordinal)
-                {
-                    "Documents",
-                    "Document",
-                    "Plugins",
-                    "Theme",
-                    "Site"
-                };
-
                 foreach (var kvp in parameters)
                 {
-                    if (cascadingKeys.Contains(kvp.Key))
+                    if (_cascadingParameterNames.Value.Contains(kvp.Key))
                     {
                         continue;
                     }