sockets.js

   1 const url = require('url');
   2 const sqlite3 = require('sqlite3');
   3 const db = new sqlite3.Database('db/vchess.sqlite');
   4
   5 module.exports = function(wss) {
   6     db.serialize(function() {
   7         db.all("SELECT * FROM Variants", (err,variants) => {
   8             let clients = { "index": {} };
   9             let games = {}; //pending games (player sid)
  10             for (const v of variants)
  11                 clients[v.name] = {};
  12             // No-op function as a callback when sending messages
  13             const noop = () => { };
  14             wss.on("connection", (socket, req) => {
  15                 const params = new URL("http://localhost" + req.url).searchParams;
  16                 const sid = params.get("sid");
  17                 const page = params.get("page");
  18                 // Ignore duplicate connections:
  19                 if (!!clients[page][sid])
  20                 {
  21                     socket.send(JSON.stringify({code:"duplicate"}));
  22                     return;
  23                 }
  24                 clients[page][sid] = socket;
  25                 if (page == "index")
  26                 {
  27                     // Send counting info
  28                     const countings = {};
  29                     for (const v of variants)
  30                         countings[v.name] = Object.keys(clients[v.name]).length;
  31                     socket.send(JSON.stringify({code:"counts",counts:countings}));
  32                 }
  33                 else
  34                 {
  35                     // Send to every client connected on index an update message for counts
  36                     Object.keys(clients["index"]).forEach( k => {
  37                         clients["index"][k].send(
  38                             JSON.stringify({code:"increase",vname:page}), noop);
  39                     });
  40                     // Also notify potential opponents:
  41                     // hit all clients which check if sid corresponds
  42                     Object.keys(clients[page]).forEach( k => {
  43                         clients[page][k].send(JSON.stringify({code:"connect",id:sid}), noop);
  44                     });
  45                     socket.on("message", objtxt => {
  46                         let obj = JSON.parse(objtxt);
  47                         switch (obj.code)
  48                         {
  49                             case "newchat":
  50                                 if (!!clients[page][obj.oppid])
  51                                 {
  52                                     clients[page][obj.oppid].send(
  53                                         JSON.stringify({code:"newchat",msg:obj.msg}), noop);
  54                                 }
  55                                 break;
  56                             case "newmove":
  57                                 if (!!clients[page][obj.oppid])
  58                                 {
  59                                     clients[page][obj.oppid].send(
  60                                         JSON.stringify({code:"newmove",move:obj.move}), noop);
  61                                 }
  62                                 break;
  63                             case "ping":
  64                                 if (!!clients[page][obj.oppid])
  65                                     socket.send(JSON.stringify({code:"pong",gameId:obj.gameId}));
  66                                 break;
  67                             case "myname":
  68                                 // Reveal my username to opponent
  69                                 if (!!clients[page][obj.oppid])
  70                                 {
  71                                     clients[page][obj.oppid].send(JSON.stringify({
  72                                         code:"oppname", name:obj.name}));
  73                                 }
  74                                 break;
  75                             case "lastate":
  76                                 if (!!clients[page][obj.oppid])
  77                                 {
  78                                     const oppId = obj.oppid;
  79                                     obj.oppid = sid; //I'm oppid for my opponent
  80                                     clients[page][oppId].send(JSON.stringify(obj), noop);
  81                                 }
  82                                 break;
  83                             case "newgame":
  84                                 if (!!games[page])
  85                                 {
  86                                     // Start a new game
  87                                     const oppId = games[page]["id"];
  88                                     const fen = games[page]["fen"];
  89                                     delete games[page];
  90                                     const mycolor = Math.random() < 0.5 ? 'w' : 'b';
  91                                     socket.send(JSON.stringify(
  92                                         {code:"newgame",fen:fen,oppid:oppId,color:mycolor}));
  93                                     if (!!clients[page][oppId])
  94                                     {
  95                                         clients[page][oppId].send(
  96                                             JSON.stringify(
  97                                                 {code:"newgame",fen:fen,oppid:sid,color:mycolor=="w"?"b":"w"}),
  98                                             noop);
  99                                     }
 100                                 }
 101                                 else
 102                                     games[page] = {id:sid, fen:obj.fen}; //wait for opponent
 103                                 break;
 104                             case "cancelnewgame": //if a user cancel his seek
 105                                 delete games[page];
 106                                 break;
 107                             case "resign":
 108                                 if (!!clients[page][obj.oppid])
 109                                     clients[page][obj.oppid].send(JSON.stringify({code:"resign"}), noop);
 110                                 break;
 111                         }
 112                     });
 113                 }
 114                 socket.on("close", () => {
 115                     delete clients[page][sid];
 116                     // Remove potential pending game
 117                     if (!!games[page] && games[page]["id"] == sid)
 118                         delete games[page];
 119                     if (page != "index")
 120                     {
 121                         // Send to every client connected on index an update message for counts
 122                         Object.keys(clients["index"]).forEach( k => {
 123                             clients["index"][k].send(
 124                                 JSON.stringify({code:"decrease",vname:page}), noop);
 125                         });
 126                     }
 127                     // Also notify potential opponents:
 128                     // hit all clients which check if sid corresponds
 129                     Object.keys(clients[page]).forEach( k => {
 130                         clients[page][k].send(JSON.stringify({code:"disconnect",id:sid}), noop);
 131                     });
 132                 });
 133             });
 134         });
 135     });
 136 }