Implement SceneServiceInjectionRequest

Author: Bronuh

KludgeBox/DI/Requests/RequestsScanner.cs

@@ -4,6 +4,7 @@
 using KludgeBox.DI.Requests.MpSyncInjection;
 using KludgeBox.DI.Requests.NotNullCheck;
 using KludgeBox.DI.Requests.ParentInjection;
+using KludgeBox.DI.Requests.SceneServiceInjection;
 using KludgeBox.Reflection.Access;
 
 namespace KludgeBox.DI.Requests;
@@ -21,6 +22,7 @@ public static RequestsScanner CreateDefault()
     {
         var scanner = new RequestsScanner();
         scanner.RegisterRequestScanner(new LoggerInjectionRequestScanner());
+        scanner.RegisterRequestScanner(new SceneServiceInjectionRequestScanner());
         scanner.RegisterRequestScanner(new DependencyCreationRequestScanner());
         scanner.RegisterRequestScanner(new ChildInjectionRequestScanner());
         scanner.RegisterRequestScanner(new ParentInjectionRequestScanner());

KludgeBox/DI/Requests/SceneServiceInjection/ISceneServiceProvider.cs

@@ -0,0 +1,11 @@
+namespace KludgeBox.DI.Requests.SceneServiceInjection;
+
+public interface ISceneServiceProvider
+{
+    /// <summary>
+    /// Returns service of specified type if found in scene or null.
+    /// </summary>
+    /// <param name="serviceType">Type of required service</param>
+    /// <returns></returns>
+    object GetService(Type serviceType);
+}

KludgeBox/DI/Requests/SceneServiceInjection/SceneServiceInjectionRequest.cs

@@ -0,0 +1,55 @@
+using Godot;
+using KludgeBox.Reflection.Access;
+
+namespace KludgeBox.DI.Requests.SceneServiceInjection;
+
+public class SceneServiceInjectionRequest : IProcessingRequest
+{
+    
+    private readonly IMemberAccessor _memberAccessor;
+    private readonly Type _serviceType;
+
+    public SceneServiceInjectionRequest(IMemberAccessor memberAccessor, Type serviceType)
+    {
+        _memberAccessor = memberAccessor;
+        _serviceType = serviceType;
+    }
+
+
+    public void ProcessOnInstance(object instance)
+    {
+        var nodeInstance = (Node)instance; // All checks are done in scanner
+        var serviceType = _serviceType ?? _memberAccessor.ValueType;
+        var service = GetService(serviceType, nodeInstance);
+        
+        if (service is null)
+        {
+            throw new InvalidOperationException($"Service of type {serviceType} not found for node {nodeInstance.GetPath()}@{nodeInstance.GetType().Name}.");
+        }
+        
+        _memberAccessor.SetValue(instance, service);
+    }
+    
+    private object GetService(Type serviceType, Node possibleServiceProvider)
+    {
+        object foundService = null;
+        
+        if (possibleServiceProvider is ISceneServiceProvider serviceProvider)
+        {
+            foundService = serviceProvider.GetService(serviceType);
+        }
+        
+        if (foundService is not null)
+        {
+            return foundService;
+        }
+        
+        var parent = possibleServiceProvider.GetParent();
+        if (!parent.IsValid())
+        {
+            return null;
+        }
+        
+        return GetService(serviceType, parent);
+    }
+}

KludgeBox/DI/Requests/SceneServiceInjection/SceneServiceInjectionRequestScanner.cs

@@ -0,0 +1,29 @@
+using Godot;
+using KludgeBox.Logging;
+using KludgeBox.Reflection.Access;
+using Serilog;
+
+namespace KludgeBox.DI.Requests.SceneServiceInjection;
+
+public class SceneServiceInjectionRequestScanner : IProcessingRequestScanner
+{
+    
+    private readonly ILogger _log = LogFactory.GetForStatic<SceneServiceInjectionRequestScanner>();
+    public bool TryGetRequest(IMemberAccessor accessor, out IProcessingRequest injectionRequest)
+    {
+        if (!accessor.TryGetAttribute<SceneServiceAttribute>(out var attribute))
+        {
+            injectionRequest = null;
+            return false;
+        }
+
+        if (!accessor.Member.ReflectedType.IsAssignableTo(typeof(Node)))
+        {
+            injectionRequest = null;
+            return false;
+        }
+        
+        injectionRequest = new SceneServiceInjectionRequest(accessor,attribute.ServiceType);
+        return true;
+    }
+}

KludgeBox/DI/Requests/SceneServiceInjection/ServiceAttribute.cs

@@ -0,0 +1,13 @@
+namespace KludgeBox.DI.Requests.SceneServiceInjection;
+
+public class SceneServiceAttribute : Attribute
+{
+    public Type ServiceType { get; }
+    
+    public SceneServiceAttribute() : this(null) { }
+
+    public SceneServiceAttribute(Type serviceType)
+    {
+        ServiceType = serviceType;
+    }
+}