From c415e2ae4883d9ec0294b8dcad997a211cd7393f Mon Sep 17 00:00:00 2001
From: Andreas Coroiu <andreas.coroiu@gmail.com>
Date: Mon, 27 Oct 2025 09:38:33 +0100
Subject: [PATCH] feat: implement function calling

---
 .../src/platform/services/sdk/rpc/proxies.ts  | 79 ++++++++++++++-----
 .../src/platform/services/sdk/rpc/rpc.spec.ts |  2 +-
 .../src/platform/services/sdk/rpc/server.ts   | 22 ++++++
 3 files changed, 82 insertions(+), 21 deletions(-)

diff --git a/libs/common/src/platform/services/sdk/rpc/proxies.ts b/libs/common/src/platform/services/sdk/rpc/proxies.ts
index 88b99e58f37..f47fbf0c6a8 100644
--- a/libs/common/src/platform/services/sdk/rpc/proxies.ts
+++ b/libs/common/src/platform/services/sdk/rpc/proxies.ts
@@ -31,7 +31,7 @@ function ProxiedReference(
       }
 
       // console.log(`Accessing ${reference.objectType}.${propertyName}`);
-      return RpcPropertyReference.create(channel, target, propertyName);
+      return RpcPropertyReference(channel, { objectReference: target, propertyName });
     },
   });
 }
@@ -39,23 +39,31 @@ function ProxiedReference(
 /**
  * A reference to a specific property on a remote object.
  */
-export class RpcPropertyReference {
-  static create(
-    channel: RpcRequestChannel,
-    objectReference: RpcObjectReference,
-    propertyName: string,
-  ): RpcPropertyReference {
-    return ProxiedReferenceProperty(
-      channel,
-      new RpcPropertyReference(objectReference, propertyName),
-    );
-  }
+type RpcPropertyReference = {
+  objectReference: RpcObjectReference;
+  propertyName: string;
+};
 
-  private constructor(
-    public objectReference: RpcObjectReference,
-    public propertyName: string,
-  ) {}
-}
+/**
+ * A reference to a specific property on a remote object.
+ */
+// export class RpcPropertyReference {
+//   static create(
+//     channel: RpcRequestChannel,
+//     objectReference: RpcObjectReference,
+//     propertyName: string,
+//   ): RpcPropertyReference {
+//     return ProxiedReferenceProperty(
+//       channel,
+//       new RpcPropertyReference(objectReference, propertyName),
+//     );
+//   }
+
+//   private constructor(
+//     public objectReference: RpcObjectReference,
+//     public propertyName: string,
+//   ) {}
+// }
 
 /**
  * A sub-proxy for a specific property of a proxied reference
@@ -66,13 +74,22 @@ export class RpcPropertyReference {
  * If this references a property then they'll try to await the value, triggering the `get` trap
  * when they access the `then` property.
  */
-function ProxiedReferenceProperty(channel: RpcRequestChannel, reference: RpcPropertyReference) {
-  return new Proxy(reference, {
+function RpcPropertyReference(channel: RpcRequestChannel, reference: RpcPropertyReference) {
+  const target = () => {};
+  Object.defineProperty(target, "name", { value: `RpcPropertyReference`, configurable: true });
+  target.objectReference = reference.objectReference;
+  target.propertyName = reference.propertyName;
+
+  return new Proxy(target, {
     get(_target, propertyName: string) {
       // console.log(
       //   `Accessing ${reference.objectReference.objectType}.${reference.propertyName}.${propertyName}`,
       // );
 
+      if (propertyName === "call") {
+        return undefined;
+      }
+
       if (propertyName !== "then") {
         throw new Error(`Cannot access property '${propertyName}' on remote proxy synchronously`);
       }
@@ -100,6 +117,28 @@ function ProxiedReferenceProperty(channel: RpcRequestChannel, reference: RpcProp
         })().then(onFulfilled, onRejected);
       };
     },
-    apply(_target, _thisArg, argArray: unknown[]) {},
+    apply(_target, _thisArg, argArray: unknown[]) {
+      // console.log(`Calling ${reference.objectReference.objectType}.${reference.propertyName}`);
+
+      // Handle method call
+      const command: Command = {
+        method: "call",
+        referenceId: reference.objectReference.referenceId,
+        propertyName: reference.propertyName,
+        args: argArray,
+      };
+
+      return channel.sendCommand(command).then((result) => {
+        if (result.status === "error") {
+          throw new Error(`RPC Error: ${result.error}`);
+        }
+
+        if (result.result.type === "value") {
+          return result.result.value;
+        } else if (result.result.type === "reference") {
+          return RpcObjectReference.create(channel, result.result.referenceId);
+        }
+      });
+    },
   });
 }
diff --git a/libs/common/src/platform/services/sdk/rpc/rpc.spec.ts b/libs/common/src/platform/services/sdk/rpc/rpc.spec.ts
index 8f96b29728f..7a3a0b74f98 100644
--- a/libs/common/src/platform/services/sdk/rpc/rpc.spec.ts
+++ b/libs/common/src/platform/services/sdk/rpc/rpc.spec.ts
@@ -23,7 +23,7 @@ describe("RpcServer", () => {
     expect(value).toBe(42);
   });
 
-  it.skip("calls sync function and returns value", async () => {
+  it("calls sync function and returns value", async () => {
     const remoteInstance = await firstValueFrom(client.getRoot());
 
     const result = await remoteInstance.greet("World");
diff --git a/libs/common/src/platform/services/sdk/rpc/server.ts b/libs/common/src/platform/services/sdk/rpc/server.ts
index f206d106989..98919732731 100644
--- a/libs/common/src/platform/services/sdk/rpc/server.ts
+++ b/libs/common/src/platform/services/sdk/rpc/server.ts
@@ -34,6 +34,28 @@ export class RpcServer<T> {
       }
     }
 
+    if (command.method === "call") {
+      const target = this.references.get<any>(command.referenceId);
+      if (!target) {
+        return { status: "error", error: `[RPC] Reference ID ${command.referenceId} not found` };
+      }
+
+      try {
+        const method = target[command.propertyName];
+        if (typeof method !== "function") {
+          return {
+            status: "error",
+            error: `[RPC] Property ${command.propertyName} is not a function`,
+          };
+        }
+
+        const result = method.apply(target, command.args);
+        return { status: "success", result: { type: "value", value: result } };
+      } catch (error) {
+        return { status: "error", error };
+      }
+    }
+
     return { status: "error", error: `Unknown command method: ${command.method}` };
   }