From 337ed6e05bd6eefebecb21c3ce04ed6f596ff7ce Mon Sep 17 00:00:00 2001
From: PalmDevs <git@palmdevs.me>
Date: Wed, 9 Apr 2025 03:33:17 +0700
Subject: [PATCH] feat(lib/utils/proxy): add `unproxify` function, improve
 typings, add workarounds

---
 lib/utils/src/proxy.ts | 70 ++++++++++++++++++++++++++++++++----------
 1 file changed, 54 insertions(+), 16 deletions(-)

diff --git a/lib/utils/src/proxy.ts b/lib/utils/src/proxy.ts
index 3eed20e..5d16d8f 100644
--- a/lib/utils/src/proxy.ts
+++ b/lib/utils/src/proxy.ts
@@ -17,20 +17,46 @@ export function getProxyTarget(obj: object) {
     return _targets.get(obj)
 }
 
-const proxifyMetadatas = new WeakMap<object, [() => unknown, cacheable: boolean, cache?: unknown]>()
+// Heavily inspired by Wintry's lazy utils, but more optimized and stripped down.
+// https://github.com/pylixonly/wintry/blob/main/src/utils/lazy.ts
 
-const proxifyHandler = Object.fromEntries(
-    Object.entries(Reflect).map(([k, fn]) => [
-        k,
-        (hint: object, ...args: any[]) => {
-            const m = proxifyMetadatas.get(hint)!
-            // @ts-expect-error
-            if (m[1]) return fn(m[2] ?? (m[2] = m[0]()), ...args)
-            // @ts-expect-error
-            return fn(m[0](), ...args)
-        },
-    ]),
-) as ProxyHandler<object>
+const _proxifyMetadatas = new WeakMap<object, [() => unknown, cacheable: boolean, cache?: unknown]>()
+
+const _proxifyHandler = {
+    ...Object.fromEntries(
+        Object.getOwnPropertyNames(Reflect).map(k => [
+            k,
+            (hint: object, ...args: any[]) => {
+                // @ts-expect-error
+                const fn = Reflect[k]
+                const meta = _proxifyMetadatas.get(hint)!
+                if (meta[1]) return fn(meta[2] ?? (meta[2] = meta[0]()), ...args)
+                return fn(meta[0](), ...args)
+            },
+        ]),
+    ),
+    // Workaround to fix functions that the correct `this`
+    get: (hint, p, recv) => {
+        const meta = _proxifyMetadatas.get(hint)!
+        const metaTarget = meta[1] ? (meta[2] ?? (meta[2] = meta[0]())) : meta[0]()
+        const val = Reflect.get(metaTarget!, p, recv)
+
+        if (val && val.__proto__ === Function.prototype)
+            return new Proxy(val, {
+                // If thisArg happens to be a proxified value, we will use the target object instead
+                apply: (fn, thisArg, args) => Reflect.apply(fn, thisArg === recv ? metaTarget : thisArg, args),
+            })
+
+        return val
+    },
+    // Workaround to fix:
+    // TypeError: getOwnPropertyDescriptor trap result is not configurable but target property '...' is configurable or non-existent
+    getOwnPropertyDescriptor: (hint, p) => {
+        const d = Reflect.getOwnPropertyDescriptor(hint, p)
+        if (d && !Reflect.getOwnPropertyDescriptor(hint, p)) Object.defineProperty(hint, p, d)
+        return d
+    },
+} as ProxyHandler<object>
 
 export type ProxifyOptions = {
     /**
@@ -51,9 +77,21 @@ export type ProxifyOptions = {
  * @param options The options to use for the proxified value.
  * @returns A proxified value that will be updated when the signal is updated.
  */
-export function proxify(signal: () => unknown, options?: ProxifyOptions) {
+export function proxify<T>(signal: () => T, options?: ProxifyOptions): T | undefined {
     // biome-ignore lint/complexity/useArrowFunction: We need a function with a constructor
     const hint = (options?.hint === 'object' ? {} : function () {}) as any
-    proxifyMetadatas.set(hint, [signal, options?.cache ?? false])
-    return new Proxy(hint, proxifyHandler)
+    _proxifyMetadatas.set(hint, [signal, options?.cache ?? false])
+    return new Proxy(hint, _proxifyHandler)
+}
+
+/**
+ * Get the value of a proxified value at the current moment.
+ * @param proxified The proxified value.
+ * @returns The unproxified value.
+ */
+export function unproxify<T extends object>(proxified: T): T | undefined {
+    const meta = _proxifyMetadatas.get(getProxyTarget(proxified)!)
+    if (!meta) throw new TypeError(`${typeof proxified} is not a proxified value`)
+    if (meta[1]) return meta[2] ?? ((meta[2] = meta[0]()) as any)
+    return meta[0]() as any
 }