commit 308f09916b88c60f145db356ee41f8b795298dbd
Author: Daniel Flanagan <daniel@lyte.dev>
Date:   Mon Nov 15 14:26:39 2021 -0600

    Possibly functional deno server

diff --git a/.gitignore b/.gitignore
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index 0000000..3922fbd
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,6 @@
+.import/
+export.cfg
+export_presets.cfg
+*.translation
+.mono
+data_*/
diff --git a/.vim/coc-settings.json b/.vim/coc-settings.json
new file mode 100644
index 0000000..a81fc3c
--- /dev/null
+++ b/.vim/coc-settings.json
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+{
+  "deno.enable": true,
+  "deno.lint": true,
+  "deno.unstable": true,
+  "prettier.disableLanguages": [
+    "typescript",
+    "javascript"
+  ],
+  "tsserver.enable": false
+}
\ No newline at end of file
diff --git a/default_env.tres b/default_env.tres
new file mode 100644
index 0000000..98f26a7
--- /dev/null
+++ b/default_env.tres
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+[gd_resource type="Environment" load_steps=2 format=2]
+[sub_resource type="ProceduralSky" id=1]
+[resource]
+background_mode = 2
+background_sky = SubResource( 1 )
diff --git a/icon.png b/icon.png
new file mode 100644
index 0000000..c98fbb6
Binary files /dev/null and b/icon.png differ
diff --git a/icon.png.import b/icon.png.import
new file mode 100644
index 0000000..a4c02e6
--- /dev/null
+++ b/icon.png.import
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+[remap]
+
+importer="texture"
+type="StreamTexture"
+path="res://.import/icon.png-487276ed1e3a0c39cad0279d744ee560.stex"
+metadata={
+"vram_texture": false
+}
+
+[deps]
+
+source_file="res://icon.png"
+dest_files=[ "res://.import/icon.png-487276ed1e3a0c39cad0279d744ee560.stex" ]
+
+[params]
+
+compress/mode=0
+compress/lossy_quality=0.7
+compress/hdr_mode=0
+compress/bptc_ldr=0
+compress/normal_map=0
+flags/repeat=0
+flags/filter=true
+flags/mipmaps=false
+flags/anisotropic=false
+flags/srgb=2
+process/fix_alpha_border=true
+process/premult_alpha=false
+process/HDR_as_SRGB=false
+process/invert_color=false
+process/normal_map_invert_y=false
+stream=false
+size_limit=0
+detect_3d=true
+svg/scale=1.0
diff --git a/project.godot b/project.godot
new file mode 100644
index 0000000..980bc49
--- /dev/null
+++ b/project.godot
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+; Engine configuration file.
+; It's best edited using the editor UI and not directly,
+; since the parameters that go here are not all obvious.
+;
+; Format:
+;   [section] ; section goes between []
+;   param=value ; assign values to parameters
+
+config_version=4
+
+[application]
+
+config/name="kdt"
+config/icon="res://icon.png"
+
+[physics]
+
+common/enable_pause_aware_picking=true
+
+[rendering]
+
+quality/driver/driver_name="GLES2"
+vram_compression/import_etc=true
+vram_compression/import_etc2=false
+environment/default_environment="res://default_env.tres"
diff --git a/readme.md b/readme.md
new file mode 100644
index 0000000..5ad06d7
--- /dev/null
+++ b/readme.md
@@ -0,0 +1,3 @@
+# Signalling Server
+
+    deno run -A server.ts
diff --git a/server.ts b/server.ts
new file mode 100644
index 0000000..3884a74
--- /dev/null
+++ b/server.ts
@@ -0,0 +1,266 @@
+const MAX_PEERS = 4096;
+const MAX_LOBBIES = 1024;
+const PORT = 9080;
+const ALFNUM = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
+
+const NO_LOBBY_TIMEOUT = 1000;
+const SEAL_CLOSE_TIMEOUT = 10000;
+const PING_INTERVAL = 10000;
+
+const STR_NO_LOBBY = "Have not joined lobby yet";
+const STR_HOST_DISCONNECTED = "Room host has disconnected";
+const STR_ONLY_HOST_CAN_SEAL = "Only host can seal the lobby";
+const STR_SEAL_COMPLETE = "Seal complete";
+const STR_TOO_MANY_LOBBIES = "Too many lobbies open, disconnecting";
+const STR_ALREADY_IN_LOBBY = "Already in a lobby";
+const STR_LOBBY_DOES_NOT_EXISTS = "Lobby does not exists";
+const STR_LOBBY_IS_SEALED = "Lobby is sealed";
+const STR_INVALID_FORMAT = "Invalid message format";
+const STR_NEED_LOBBY = "Invalid message when not in a lobby";
+const STR_SERVER_ERROR = "Server error, lobby not found";
+const STR_INVALID_DEST = "Invalid destination";
+const STR_INVALID_CMD = "Invalid command";
+const STR_TOO_MANY_PEERS = "Too many peers connected";
+
+function randomInt(low: number, high: number) {
+  return Math.floor(Math.random() * (high - low + 1) + low);
+}
+
+function randomId() {
+  const arr = new Int32Array(1);
+  crypto.getRandomValues(arr);
+  return Math.abs(arr[0]);
+}
+
+function randomSecret() {
+  let out = "";
+  for (let i = 0; i < 16; i++) {
+    out += ALFNUM[randomInt(0, ALFNUM.length - 1)];
+  }
+  return out;
+}
+
+class ProtoError extends Error {
+  code: number;
+
+  constructor(code: number, message: string) {
+    super(message);
+    this.code = code;
+  }
+}
+
+class Peer {
+  id: number;
+  ws: WebSocket;
+  lobby: string;
+  timeout: number;
+
+  constructor(id: number, ws: WebSocket) {
+    this.id = id;
+    this.ws = ws;
+    this.lobby = "";
+    // Close connection after 1 sec if client has not joined a lobby
+    this.timeout = setTimeout(() => {
+      if (!this.lobby) ws.close(4000, STR_NO_LOBBY);
+    }, NO_LOBBY_TIMEOUT);
+  }
+}
+
+class Lobby {
+  name: string;
+  host: number;
+  peers: Peer[];
+  sealed: boolean;
+  closeTimer: number;
+
+  constructor(name: string, host: number) {
+    this.name = name;
+    this.host = host;
+    this.peers = [];
+    this.sealed = false;
+    this.closeTimer = -1;
+  }
+
+  getPeerId(peer: Peer) {
+    if (this.host === peer.id) return 1;
+    return peer.id;
+  }
+
+  join(peer: Peer) {
+    const assigned = this.getPeerId(peer);
+    peer.ws.send(`I: ${assigned}\n`);
+    this.peers.forEach((p) => {
+      p.ws.send(`N: ${assigned}\n`);
+      peer.ws.send(`N: ${this.getPeerId(p)}\n`);
+    });
+    this.peers.push(peer);
+  }
+  leave(peer: Peer) {
+    const idx = this.peers.findIndex((p) => peer === p);
+    if (idx === -1) return false;
+    const assigned = this.getPeerId(peer);
+    const close = assigned === 1;
+    this.peers.forEach((p) => {
+      // Room host disconnected, must close.
+      if (close) p.ws.close(4000, STR_HOST_DISCONNECTED);
+      // Notify peer disconnect.
+      else p.ws.send(`D: ${assigned}\n`);
+    });
+    this.peers.splice(idx, 1);
+    if (close && this.closeTimer >= 0) {
+      // We are closing already.
+      clearTimeout(this.closeTimer);
+      this.closeTimer = -1;
+    }
+    return close;
+  }
+  seal(peer: Peer) {
+    // Only host can seal
+    if (peer.id !== this.host) {
+      throw new ProtoError(4000, STR_ONLY_HOST_CAN_SEAL);
+    }
+    this.sealed = true;
+    this.peers.forEach((p) => {
+      p.ws.send("S: \n");
+    });
+    console.log(
+      `Peer ${peer.id} sealed lobby ${this.name} ` +
+        `with ${this.peers.length} peers`,
+    );
+    this.closeTimer = setTimeout(() => {
+      // Close peer connection to host (and thus the lobby)
+      this.peers.forEach((p) => {
+        p.ws.close(1000, STR_SEAL_COMPLETE);
+      });
+    }, SEAL_CLOSE_TIMEOUT);
+  }
+}
+
+const lobbies = new Map();
+let peersCount = 0;
+
+function joinLobby(peer: Peer, lobbyName: string) {
+  if (lobbyName === "") {
+    if (lobbies.size >= MAX_LOBBIES) {
+      throw new ProtoError(4000, STR_TOO_MANY_LOBBIES);
+    }
+    // Peer must not already be in a lobby
+    if (peer.lobby !== "") {
+      throw new ProtoError(4000, STR_ALREADY_IN_LOBBY);
+    }
+    lobbyName = randomSecret();
+    lobbies.set(lobbyName, new Lobby(lobbyName, peer.id));
+    console.log(`Peer ${peer.id} created lobby ${lobbyName}`);
+    console.log(`Open lobbies: ${lobbies.size}`);
+  }
+  const lobby = lobbies.get(lobbyName);
+  if (!lobby) throw new ProtoError(4000, STR_LOBBY_DOES_NOT_EXISTS);
+  if (lobby.sealed) throw new ProtoError(4000, STR_LOBBY_IS_SEALED);
+  peer.lobby = lobbyName;
+  console.log(
+    `Peer ${peer.id} joining lobby ${lobbyName} ` +
+      `with ${lobby.peers.length} peers`,
+  );
+  lobby.join(peer);
+  peer.ws.send(`J: ${lobbyName}\n`);
+}
+
+function parseMsg(peer: Peer, msg: string) {
+  const sep = msg.indexOf("\n");
+  if (sep < 0) throw new ProtoError(4000, STR_INVALID_FORMAT);
+
+  const cmd = msg.slice(0, sep);
+  if (cmd.length < 3) throw new ProtoError(4000, STR_INVALID_FORMAT);
+
+  const data = msg.slice(sep);
+
+  // Lobby joining.
+  if (cmd.startsWith("J: ")) {
+    joinLobby(peer, cmd.substr(3).trim());
+    return;
+  }
+
+  if (!peer.lobby) throw new ProtoError(4000, STR_NEED_LOBBY);
+  const lobby = lobbies.get(peer.lobby);
+  if (!lobby) throw new ProtoError(4000, STR_SERVER_ERROR);
+
+  // Lobby sealing.
+  if (cmd.startsWith("S: ")) {
+    lobby.seal(peer);
+    return;
+  }
+
+  // Message relaying format:
+  //
+  // [O|A|C]: DEST_ID\n
+  // PAYLOAD
+  //
+  // O: Client is sending an offer.
+  // A: Client is sending an answer.
+  // C: Client is sending a candidate.
+  let destId = parseInt(cmd.substr(3).trim());
+  // Dest is not an ID.
+  if (!destId) throw new ProtoError(4000, STR_INVALID_DEST);
+  if (destId === 1) destId = lobby.host;
+  const dest = lobby.peers.find((p: Peer) => p.id === destId);
+  // Dest is not in this room.
+  if (!dest) throw new ProtoError(4000, STR_INVALID_DEST);
+
+  function isCmd(what: string) {
+    return cmd.startsWith(`${what}: `);
+  }
+  if (isCmd("O") || isCmd("A") || isCmd("C")) {
+    dest.ws.send(cmd[0] + ": " + lobby.getPeerId(peer) + data);
+    return;
+  }
+  throw new ProtoError(4000, STR_INVALID_CMD);
+}
+
+console.log(`Server running on port ${PORT}`);
+const conn = Deno.listen({ port: PORT });
+const httpConn = Deno.serveHttp(await conn.accept());
+const e = await httpConn.nextRequest();
+if (e) {
+  const { socket, response } = Deno.upgradeWebSocket(e.request);
+  const id = randomId();
+  const peer = new Peer(id, socket);
+  socket.onopen = (_ev) => {
+    if (peersCount >= MAX_PEERS) {
+      socket.close(4000, STR_TOO_MANY_PEERS);
+      return;
+    }
+    peersCount++;
+  };
+  socket.onmessage = (ev) => {
+    try {
+      parseMsg(peer, ev.data);
+    } catch (e) {
+      const code = e.code || 4000;
+      console.log(`Error parsing message from ${id}:\n` + ev.data);
+      socket.close(code, e.message);
+    }
+  };
+  socket.onclose = (ev) => {
+    peersCount--;
+    console.log(
+      `Connection with peer ${peer.id} closed ` +
+        `with reason: ${ev.reason}`,
+    );
+    if (
+      peer.lobby &&
+      lobbies.has(peer.lobby) &&
+      lobbies.get(peer.lobby).leave(peer)
+    ) {
+      lobbies.delete(peer.lobby);
+      console.log(`Deleted lobby ${peer.lobby}`);
+      console.log(`Open lobbies: ${lobbies.size}`);
+      peer.lobby = "";
+    }
+    if (peer.timeout >= 0) {
+      clearTimeout(peer.timeout);
+      peer.timeout = -1;
+    }
+  };
+  socket.onerror = (e) => console.error("WebSocket error:", e);
+  e.respondWith(response);
+}