sockets.js

   1 //const url = require('url');
   2 const Variants = require("./variants");
   3
   4 function getJsonFromUrl(url) {
   5     var query = url.substr(2); //starts with "/?"
   6     var result = {};
   7     query.split("&").forEach(function(part) {
   8         var item = part.split("=");
   9         result[item[0]] = decodeURIComponent(item[1]);
  10     });
  11     return result;
  12 }
  13
  14 module.exports = function(wss) {
  15
  16     let clients = { "index": {} };
  17     let games = {}; //pending games (player sid)
  18     for (const v of Variants)
  19         clients[v.name] = {};
  20
  21     // TODO: when relaying to opponent, check readyState, potential setTimeout()? + send opponent (re)disconnect
  22     // (resign, newgame, newmove). See https://github.com/websockets/ws/blob/master/lib/websocket.js around line 313
  23
  24     wss.on("connection", (socket, req) => {
  25         //const params = new URL("http://localhost" + req.url).searchParams;
  26         var query = getJsonFromUrl(req.url);
  27         const sid = query["sid"]; //params.get("sid");
  28         const page = query["page"]; //params.get("page");
  29         clients[page][sid] = socket;
  30         if (page == "index")
  31         {
  32             // Send counting info
  33             const countings = {};
  34             for (const v of Variants)
  35                 countings[v.name] = Object.keys(clients[v.name]).length;
  36             socket.send(JSON.stringify({code:"counts",counts:countings}));
  37         }
  38         else
  39         {
  40             // Send to every client connected on index an update message for counts
  41             Object.keys(clients["index"]).forEach( k => {
  42                 clients["index"][k].send(JSON.stringify({code:"increase",vname:page}));
  43             });
  44             // Also notify potential opponents: hit all clients which check if sid corresponds
  45             Object.keys(clients[page]).forEach( k => {
  46                 clients[page][k].send(JSON.stringify({code:"connect",id:sid}));
  47             });
  48             socket.on("message", objtxt => {
  49                 let obj = JSON.parse(objtxt);
  50                 switch (obj.code)
  51                 {
  52                     case "newmove":
  53                         clients[page][obj.oppid].send(JSON.stringify({code:"newmove",move:obj.move}));
  54                         break;
  55                     case "ping":
  56                         if (!!clients[page][obj.oppid])
  57                             socket.send(JSON.stringify({code:"pong"}));
  58                         break;
  59                     case "newgame":
  60                         if (!!games[page])
  61                         {
  62                             // Start a new game
  63                             const oppId = games[page]["id"];
  64                             const fen = games[page]["fen"];
  65                             delete games[page];
  66                             const mycolor = Math.random() < 0.5 ? 'w' : 'b';
  67                             socket.send(JSON.stringify({code:"newgame",fen:fen,oppid:oppId,color:mycolor}));
  68                             clients[page][oppId].send(JSON.stringify({code:"newgame",fen:fen,oppid:sid,color:mycolor=="w"?"b":"w"}));
  69                         }
  70                         else
  71                             games[page] = {id:sid, fen:obj.fen}; //wait for opponent
  72                         break;
  73                     case "resign":
  74                         clients[page][obj.oppid].send(JSON.stringify({code:"resign"}));
  75                         break;
  76                 }
  77             });
  78         }
  79         socket.on("close", () => {
  80             delete clients[page][sid];
  81             // Remove potential pending game
  82             if (!!games[page] && games[page]["id"] == sid)
  83                 delete games[page];
  84             if (page != "index")
  85             {
  86                 // Send to every client connected on index an update message for counts
  87                 Object.keys(clients["index"]).forEach( k => {
  88                     clients["index"][k].send(JSON.stringify({code:"decrease",vname:page}));
  89                 });
  90             }
  91             // Also notify potential opponents: hit all clients which check if sid corresponds
  92             Object.keys(clients[page]).forEach( k => {
  93                 clients[page][k].send(JSON.stringify({code:"disconnect",id:sid}));
  94             });
  95         });
  96     });
  97 }