From e9c73ae99804c1766230bda94f9f732f4492f0a1 Mon Sep 17 00:00:00 2001
From: Tangent Wantwight <tangent128@gmail.com>
Date: Sun, 17 May 2020 23:47:50 -0400
Subject: [PATCH] Implement connection to websocket server

---
 package-lock.json     |  8 +++++++
 package.json          |  1 +
 plan.txt              |  3 +++
 src/ecs/Data.ts       | 11 ++++++++++
 src/index.ts          | 10 +++++----
 src/net/Connection.ts | 50 +++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 79 insertions(+), 4 deletions(-)
 create mode 100644 src/net/Connection.ts

diff --git a/package-lock.json b/package-lock.json
index c062a76..5d0cb22 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -2685,6 +2685,14 @@
         "callbag-share": "^1.1.1"
       }
     },
+    "callbag-create": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/callbag-create/-/callbag-create-2.1.0.tgz",
+      "integrity": "sha512-ypHk+Pdqq0Cmgb7+kszctTHWuqLEX1dTNL0BMWld68ARtEtbGMnikzTY5A4oWc1tgZGixtjCx5cpc3l5aUyUAg==",
+      "requires": {
+        "callbag": "1.2.0"
+      }
+    },
     "callbag-map": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/callbag-map/-/callbag-map-1.1.0.tgz",
diff --git a/package.json b/package.json
index d40d993..937fceb 100644
--- a/package.json
+++ b/package.json
@@ -22,6 +22,7 @@
   "dependencies": {
     "callbag": "^1.2.0",
     "callbag-animation-frames": "^2.1.0",
+    "callbag-create": "^2.1.0",
     "callbag-map": "^1.1.0",
     "callbag-pipe": "^1.2.0",
     "callbag-share": "^1.2.0",
diff --git a/plan.txt b/plan.txt
index b2b7e26..f671e17 100644
--- a/plan.txt
+++ b/plan.txt
@@ -1,5 +1,8 @@
 Open:
 - Insecured websocket server implementation
+    - desynced on join
+    - reset on join
+    - sync to op on join
 - Cloneable RNG that goes in state (use MurmurHash3 finalizer in counter mode?)
 - remove all random() calls
 
diff --git a/src/ecs/Data.ts b/src/ecs/Data.ts
index 40ec0ab..1ac8265 100644
--- a/src/ecs/Data.ts
+++ b/src/ecs/Data.ts
@@ -1,4 +1,15 @@
 
+export type Jsonified<T> = {
+    [K in keyof T]: JsonEncoded<T[K]>;
+};
+export type JsonEncoded<T> =
+    T extends Function ? never
+    : T extends Date ? string
+    : T extends (infer U)[] ? JsonEncoded<U>[]
+    : T extends Record<string, any> ? Jsonified<T>
+    : T
+    ;
+
 export type Store<T extends Component<T>> = Record<number, T>;
 export interface Clone<T> {
     clone(): T;
diff --git a/src/index.ts b/src/index.ts
index 484caab..22eff75 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -3,7 +3,8 @@ import { KeyName } from "./applet/Keyboard";
 import { BindTests } from "./ecs/test";
 import { Data } from "./game/GameComponents";
 import { Main } from "./game/Main";
-import { LoopbackServer } from "./net/LoopbackServer";
+import { Connection } from "./net/Connection";
+import {} from "./net/LoopbackServer";
 
 /* // Hot Module Reloading stub, if that's viable
  * declare const module: any;
@@ -16,8 +17,9 @@ import { LoopbackServer } from "./net/LoopbackServer";
  * }
  */
 
-const server = new LoopbackServer<KeyName[], Data>();
-
-Select(".GameCanvas").forEachCanvas((c, cx, keys) => new Main(c, cx, keys, server.socket));
+Select(".GameCanvas").forEachCanvas((c, cx, keys) => {
+    const connection = new Connection<KeyName[], Data>("ws://localhost:9090/");
+    new Main(c, cx, keys, connection.socket);
+});
 
 BindTests();
diff --git a/src/net/Connection.ts b/src/net/Connection.ts
new file mode 100644
index 0000000..cae44c9
--- /dev/null
+++ b/src/net/Connection.ts
@@ -0,0 +1,50 @@
+import { Callbag, Source } from "callbag";
+import create from "callbag-create";
+import pipe from "callbag-pipe";
+import share from "callbag-share";
+
+import { Jsonified } from "../ecs/Data";
+import { catchTalkback, defer, interval, makeSubject, map, merge } from "../utilities/Callbag";
+import { ClientMessage, MessageTypes, ServerMessage } from "./LockstepClient";
+
+type Server<LocalInput, State> = Callbag<ClientMessage<LocalInput, State>, ServerMessage<LocalInput[], State>>;
+
+/** Connection to a websocket server that handles multiple clients, for schemes where GlobalInput = LocalInput[] */
+export class Connection<LocalInput, State> {
+
+    public constructor(
+        private url: string
+    ) { }
+
+    public readonly socket = defer(() => {
+        const ws = new WebSocket(this.url);
+
+        const source: Source<ServerMessage<LocalInput[], State>> = create((data, { }, close) => {
+            ws.onopen = () => {
+                // fake a HELO message & set state message until the server actually sends them
+                data({ t: MessageTypes.META, helo: "Websocket Server" });
+                data({ t: MessageTypes.SET_STATE, u: 0, s: {} });
+            };
+            ws.onmessage = msg => {
+                const decoded: Jsonified<ServerMessage<LocalInput[], State>> = JSON.parse(msg.data);
+                data(decoded as ServerMessage<LocalInput[], State>);
+            };
+            ws.onclose = () => {
+                close();
+            };
+
+            return () => {
+                // cleanup
+                ws.close();
+            };
+        });
+
+        return pipe(
+            source,
+            catchTalkback((message: ClientMessage<LocalInput, State>) => {
+                const encoded = JSON.stringify(message);
+                ws.send(encoded);
+            })
+        );
+    });
+}