dc8bd97922c7b7f8a007187c29366823e85d2b6f
[xogo.git] / server.js
1 const params = require("./parameters.js");
2 const WebSocket = require("ws");
3 const wss = new WebSocket.Server({
4 port: params.socket_port,
5 path: params.socket_path
6 });
7
8 let challenges = {}; //variantName --> socketId, name
9 let games = {}; //gameId --> gameInfo (vname, fen, players, options, time)
10 let moveHash = {}; //gameId --> set of hashes seen so far
11 let sockets = {}; //socketId --> socket
12 const variants = require("./variants.js");
13 const Crypto = require("crypto");
14 const randstrSize = 8;
15
16 function send(sid, code, data) {
17 const socket = sockets[sid];
18 // If a player deletes local infos and then tries to resume a game,
19 // sockets[oppSid] will probably not exist anymore:
20 if (socket)
21 socket.send(JSON.stringify(Object.assign({code: code}, data)));
22 }
23
24 function initializeGame(vname, players, options) {
25 const gid =
26 Crypto.randomBytes(randstrSize).toString("hex").slice(0, randstrSize);
27 games[gid] = {
28 vname: vname,
29 players: players,
30 options: options,
31 time: Date.now()
32 };
33 return gid;
34 }
35
36 // Provide seed in case of, so that both players initialize with same FEN
37 function launchGame(gid) {
38 moveHash[gid] = {};
39 const gameInfo = Object.assign(
40 {seed: Math.floor(Math.random() * 19840), gid: gid},
41 games[gid]
42 );
43 // players array is supposed to be full:
44 for (const p of games[gid].players)
45 send(p.sid, "gamestart", gameInfo);
46 }
47
48 function getRandomVariant() {
49 // Pick a variant at random in the list
50 const index = Math.floor(Math.random() * variants.length);
51 return variants[index].name;
52 }
53
54 wss.on("connection", (socket, req) => {
55 const sid = req.url.split("=")[1]; //...?sid=...
56 sockets[sid] = socket;
57 socket.isAlive = true;
58 socket.on("pong", () => socket.isAlive = true);
59
60 socket.on("message", (msg) => {
61 const obj = JSON.parse(msg);
62 switch (obj.code) {
63 // Send challenge (may trigger game creation)
64 case "seekgame": {
65 let oppIndex = undefined, //variant name
66 choice = undefined; //variant finally played
67 const vname = obj.vname, //variant requested
68 randvar = (obj.vname == "_random");
69 if (vname == "_random") {
70 // Pick any current challenge if possible
71 const currentChalls = Object.keys(challenges);
72 if (currentChalls.length >= 1) {
73 choice =
74 currentChalls[Math.floor(Math.random() * currentChalls.length)];
75 oppIndex = choice;
76 }
77 }
78 else if (challenges[vname]) {
79 // Anyone wanting to play the same variant ?
80 choice = vname;
81 oppIndex = vname;
82 }
83 else if (challenges["_random"]) {
84 // Anyone accepting any variant (including vname) ?
85 choice = vname;
86 oppIndex = "_random";
87 }
88 if (oppIndex) {
89 if (choice == "_random")
90 choice = getRandomVariant();
91 // Launch game
92 let players = [
93 {sid: sid, name: obj.name, randvar: randvar},
94 Object.assign({}, challenges[oppIndex])
95 ];
96 delete challenges[oppIndex];
97 if (Math.random() < 0.5)
98 players = players.reverse();
99 // Empty options = default
100 launchGame( initializeGame(choice, players, {}) );
101 }
102 else
103 // Place challenge and wait. 'randvar' indicate if we play anything
104 challenges[vname] = {sid: sid, name: obj.name, randvar: randvar};
105 break;
106 }
107 // Set FEN after game was created (received twice)
108 case "setfen":
109 games[obj.gid].fen = obj.fen;
110 break;
111 // Send back game informations
112 case "getgame":
113 if (!games[obj.gid])
114 send(sid, "nogame");
115 else
116 send(sid, "gameinfo", games[obj.gid]);
117 break;
118 // Cancel challenge
119 case "cancelseek":
120 delete challenges[obj.vname];
121 break;
122 // Receive rematch
123 case "rematch":
124 if (!games[obj.gid])
125 send(sid, "closerematch");
126 else {
127 const myIndex = (games[obj.gid].players[0].sid == sid ? 0 : 1);
128 if (!games[obj.gid].rematch)
129 games[obj.gid].rematch = [0, 0];
130 games[obj.gid].rematch[myIndex] = !obj.random ? 1 : 2;
131 if (games[obj.gid].rematch[1-myIndex]) {
132 // Launch new game, colors reversed
133 let vname = games[obj.gid].vname;
134 const allrand = games[obj.gid].rematch.every(r => r == 2);
135 if (allrand)
136 vname = getRandomVariant();
137 games[obj.gid].players.forEach(p => p.randvar = allrand);
138 const gid = initializeGame(vname,
139 games[obj.gid].players.reverse(),
140 games[obj.gid].options);
141 launchGame(gid);
142 }
143 }
144 break;
145 // Rematch cancellation
146 case "norematch":
147 if (games[obj.gid]) {
148 const myIndex = (games[obj.gid].players[0].sid == sid ? 0 : 1);
149 send(games[obj.gid].players[1-myIndex].sid, "closerematch");
150 }
151 break;
152 // Create game vs. friend
153 case "creategame": {
154 let players = [
155 {sid: obj.player.sid, name: obj.player.name},
156 undefined
157 ];
158 if (
159 obj.player.color == 'b' ||
160 (obj.player.color == '' && Math.random() < 0.5)
161 ) {
162 players = players.reverse();
163 }
164 // Incomplete players array: do not start game yet
165 const gid = initializeGame(obj.vname, players, obj.options);
166 send(sid, "gamecreated", {gid: gid});
167 // If nobody joins within 3 minutes, delete game
168 setTimeout(
169 () => {
170 if (games[gid] && games[gid].players.some(p => !p))
171 delete games[gid];
172 },
173 3 * 60000
174 );
175 break;
176 }
177 // Join game vs. friend
178 case "joingame":
179 if (!games[obj.gid])
180 send(sid, "jointoolate");
181 else {
182 const emptySlot = games[obj.gid].players.findIndex(p => !p);
183 if (emptySlot < 0)
184 send(sid, "jointoolate");
185 else {
186 // Join a game (started by some other player)
187 games[obj.gid].players[emptySlot] = {sid: sid, name: obj.name};
188 launchGame(obj.gid);
189 }
190 }
191 break;
192 // Relay a move + update games object
193 case "newmove":
194 // NOTE: still potential racing issues, but... fingers crossed
195 const hash = Crypto.createHash("md5")
196 .update(JSON.stringify(obj.fen))
197 .digest("hex");
198 if (moveHash[hash])
199 break;
200 moveHash[hash] = true;
201 games[obj.gid].fen = obj.fen;
202 games[obj.gid].time = Date.now(); //update timestamp in case of
203 const playingWhite = (games[obj.gid].players[0].sid == sid);
204 const oppSid = games[obj.gid].players[playingWhite ? 1 : 0].sid;
205 send(oppSid, "newmove", {moves: obj.moves});
206 break;
207 // Relay "game ends" message
208 case "gameover":
209 if (obj.relay) {
210 const playingWhite = (games[obj.gid].players[0].sid == sid);
211 const oppSid = games[obj.gid].players[playingWhite ? 1 : 0].sid;
212 send(oppSid, "gameover", { gid: obj.gid });
213 }
214 // 2 minutes timeout for rematch:
215 setTimeout(() => delete games[obj.gid], 2 * 60000);
216 break;
217 }
218 });
219 socket.on("close", () => {
220 delete sockets[sid];
221 for (const [key, value] of Object.entries(challenges)) {
222 if (value.sid == sid) {
223 delete challenges[key];
224 break; //only one challenge per player
225 }
226 }
227 for (let g of Object.values(games)) {
228 const myIndex = g.players.findIndex(p => p && p.sid == sid);
229 if (myIndex >= 0) {
230 if (g.rematch && g.rematch[myIndex] > 0) g.rematch[myIndex] = 0;
231 break; //only one game per player
232 }
233 }
234 });
235 });
236
237 const heartbeat = setInterval(() => {
238 wss.clients.forEach((ws) => {
239 if (ws.isAlive === false)
240 return ws.terminate();
241 ws.isAlive = false;
242 ws.ping();
243 });
244 }, 30000);
245
246 // Every 24 hours, scan games and remove if last move older than 24h
247 const dayInMillisecs = 24 * 60 * 60 * 1000;
248 const killOldGames = setInterval(() => {
249 const now = Date.now();
250 Object.keys(games).forEach(gid => {
251 if (now - games[gid].time >= dayInMillisecs)
252 delete games[gid];
253 });
254 }, dayInMillisecs);
255
256 // TODO: useful code here?
257 wss.on("close", () => {
258 clearInterval(heartbeat);
259 clearInterval(killOldGames);
260 });