From 81873f368946ad64882b0c2a190190ada2d1f92a Mon Sep 17 00:00:00 2001
From: Max P <Mail@MPassarello.de>
Date: Sat, 24 Aug 2024 02:21:50 +0200
Subject: [PATCH] feat!: Update `RegisterInstance` Decorator for stable
 decorator api of typescript

---
 src/decorators/RegisterInstance.ts | 63 +++++++++++++++++-------------
 1 file changed, 35 insertions(+), 28 deletions(-)

diff --git a/src/decorators/RegisterInstance.ts b/src/decorators/RegisterInstance.ts
index d638f6e..959baa4 100644
--- a/src/decorators/RegisterInstance.ts
+++ b/src/decorators/RegisterInstance.ts
@@ -1,3 +1,4 @@
+import { IdentifierRequiredError } from 'src/interfaces/Exceptions';
 import { TSinjex } from '../classes/TSinjex';
 import { Identifier } from '../types/Identifier';
 import { InitDelegate } from '../types/InitDelegate';
@@ -5,12 +6,11 @@ import { InitDelegate } from '../types/InitDelegate';
 /**
  * A decorator to register an instance of a class in the DI (Dependency Injection) container.
  * @template TargetType The type of the class whose instance is to be registered.
- * @param identifier The identifier used to register the instance in the DI container.
- * @see {@link Identifier} for more information on identifiers.
- * @param init An optional initializer function which get the constructor of the class
+ * @param identifier The {@link Identifier|identifier} used to register the class in the DI container or the class name if not provided.
+ * @param init An optional initializer {@link InitDelegate|function} which get the constructor of the class
  * as input and returns an instance of the class.
- * @see {@link InitDelegate} for more information on initializer functions.
  * @returns The decorator function to be applied on the class.
+ * @throws An {@link IdentifierRequiredError} if the identifier is not provided and the class name is not available.
  * @example
  * ```ts
  * \@RegisterInstance('MyClassInstanceIdentifier', (constructor) => new constructor())
@@ -22,43 +22,51 @@ import { InitDelegate } from '../types/InitDelegate';
 export function RegisterInstance<
     TargetType extends new (..._args: unknown[]) => InstanceType<TargetType>,
 >(
-    identifier: Identifier,
+    identifier?: Identifier,
     init?: InitDelegate<
         TargetType & { new (..._args: unknown[]): InstanceType<TargetType> },
         InstanceType<TargetType>
     >,
 ) {
-    return function (constructor: TargetType, ...args: unknown[]): void {
-        // Get the instance of the DI container
+    return function (
+        constructor: TargetType,
+        context: ClassDecoratorContext<TargetType>,
+    ): void {
+        const _identifier = identifier ?? context.name;
+
+        if (_identifier == null) throw new IdentifierRequiredError();
+
         const diContainer = TSinjex.getInstance();
         let instance: InstanceType<TargetType>;
 
+        /**
+         * Get the instance of the class
+         * and replace the lazy proxy with the instance
+         * for performance optimization.
+         */
+        const getAndRegisterInstance = (): void => {
+            if (instance == null) {
+                if (init) {
+                    instance = init(constructor);
+                } else {
+                    instance = new constructor();
+                }
+            }
+            diContainer.register(_identifier, instance);
+        };
+
         // Create a proxy to instantiate the class when needed (Lazy Initialization)
-        let lazyProxy: unknown = new Proxy(
+        const lazyProxy: unknown = new Proxy(
             {},
             {
-                get(target, prop, receiver) {
-                    if (instance == null) {
-                        if (init) {
-                            instance = init(constructor);
-                        } else {
-                            instance = new constructor(...args);
-                        }
-                    }
-                    lazyProxy = instance;
+                get(_target, prop, _receiver) {
+                    getAndRegisterInstance();
 
                     // Return the requested property of the instance
                     return instance[prop as keyof InstanceType<TargetType>];
                 },
-                set(target, prop, value, receiver) {
-                    if (instance == null) {
-                        if (init) {
-                            instance = init(constructor);
-                        } else {
-                            instance = new constructor(...args);
-                        }
-                    }
-                    lazyProxy = instance;
+                set(_target, prop, value, _receiver) {
+                    getAndRegisterInstance();
 
                     // Set the requested property of the instance
                     return (instance[prop as keyof InstanceType<TargetType>] =
@@ -67,7 +75,6 @@ export function RegisterInstance<
             },
         );
 
-        // Register the lazy proxy in the DI container
-        diContainer.register(identifier, lazyProxy);
+        diContainer.register(_identifier, lazyProxy);
     };
 }