sockets.js

   1 const url = require('url');
   2 const Variants = require("./variants");
   3
   4 module.exports = function(wss) {
   5
   6     let clients = { "index": {} };
   7     let games = {}; //pending games (player sid)
   8     for (const v of Variants)
   9         clients[v.name] = {};
  10
  11 //  // Safety counter (TODO: is it necessary ?)
  12 //  setInterval(() => {
  13 //      Object.keys(clients).forEach(k => {
  14 //          Object.keys(clients[k]).forEach(ck => {
  15 //              if (!clients[k][ck] || clients[k][ck].readyState != 1)
  16 //                  delete clients[k][ck];
  17 //          });
  18 //      });
  19 //  }, 60000); //every minute (will be lowered if a lot of users...)
  20
  21     // No-op function as a callback when sending messages
  22     const noop = () => { };
  23
  24     wss.on("connection", (socket, req) => {
  25         const params = new URL("http://localhost" + req.url).searchParams;
  26         const sid = params.get("sid");
  27         const page = params.get("page");
  28         // Ignore duplicate connections:
  29         if (!!clients[page][sid])
  30         {
  31             socket.send(JSON.stringify({code:"duplicate"}));
  32             return;
  33         }
  34         clients[page][sid] = socket;
  35         if (page == "index")
  36         {
  37             // Send counting info
  38             const countings = {};
  39             for (const v of Variants)
  40                 countings[v.name] = Object.keys(clients[v.name]).length;
  41             socket.send(JSON.stringify({code:"counts",counts:countings}));
  42         }
  43         else
  44         {
  45             // Send to every client connected on index an update message for counts
  46             Object.keys(clients["index"]).forEach( k => {
  47                 clients["index"][k].send(JSON.stringify({code:"increase",vname:page}), noop);
  48             });
  49             // Also notify potential opponents: hit all clients which check if sid corresponds
  50             Object.keys(clients[page]).forEach( k => {
  51                 clients[page][k].send(JSON.stringify({code:"connect",id:sid}), noop);
  52             });
  53             socket.on("message", objtxt => {
  54                 let obj = JSON.parse(objtxt);
  55                 switch (obj.code)
  56                 {
  57                     case "newmove":
  58                         if (!!clients[page][obj.oppid])
  59                         {
  60                             clients[page][obj.oppid].send(
  61                                 JSON.stringify({code:"newmove",move:obj.move}), noop);
  62                         }
  63                         break;
  64                     case "ping":
  65                         if (!!clients[page][obj.oppid])
  66                             socket.send(JSON.stringify({code:"pong"}));
  67                         break;
  68                     case "lastate":
  69                         if (!!clients[page][obj.oppid])
  70                         {
  71                             const oppId = obj.oppid;
  72                             obj.oppid = sid; //I'm oppid for my opponent
  73                             clients[page][oppId].send(JSON.stringify(obj), noop);
  74                         }
  75                         break;
  76                     case "newgame":
  77                         if (!!games[page])
  78                         {
  79                             // Start a new game
  80                             const oppId = games[page]["id"];
  81                             const fen = games[page]["fen"];
  82                             delete games[page];
  83                             const mycolor = Math.random() < 0.5 ? 'w' : 'b';
  84                             socket.send(
  85                                 JSON.stringify({code:"newgame",fen:fen,oppid:oppId,color:mycolor}));
  86                             if (!!clients[page][oppId])
  87                             {
  88                                 clients[page][oppId].send(
  89                                     JSON.stringify(
  90                                         {code:"newgame",fen:fen,oppid:sid,color:mycolor=="w"?"b":"w"}),
  91                                     noop);
  92                             }
  93                         }
  94                         else
  95                             games[page] = {id:sid, fen:obj.fen}; //wait for opponent
  96                         break;
  97                     case "cancelnewgame": //if a user cancel his seek
  98                         delete games[page];
  99                         break;
 100                     case "resign":
 101                         if (!!clients[page][obj.oppid])
 102                             clients[page][obj.oppid].send(JSON.stringify({code:"resign"}), noop);
 103                         break;
 104                 }
 105             });
 106         }
 107         socket.on("close", () => {
 108             delete clients[page][sid];
 109             // Remove potential pending game
 110             if (!!games[page] && games[page]["id"] == sid)
 111                 delete games[page];
 112             if (page != "index")
 113             {
 114                 // Send to every client connected on index an update message for counts
 115                 Object.keys(clients["index"]).forEach( k => {
 116                     clients["index"][k].send(JSON.stringify({code:"decrease",vname:page}), noop);
 117                 });
 118             }
 119             // Also notify potential opponents: hit all clients which check if sid corresponds
 120             Object.keys(clients[page]).forEach( k => {
 121                 clients[page][k].send(JSON.stringify({code:"disconnect",id:sid}), noop);
 122             });
 123         });
 124     });
 125 }