Very basic anti-bot strategy for problems upload: do not pre-generate FEN

[vchess.git] / sockets.js

const url = require('url');
const sqlite3 = require('sqlite3');
const db = new sqlite3.Database('db/vchess.sqlite');

module.exports = function(wss) {
	db.serialize(function() {
		db.all("SELECT * FROM Variants", (err,variants) => {
			let clients = { "index": {} };
			let games = {}; //pending games (player sid)
			for (const v of variants)
				clients[v.name] = {};
			// No-op function as a callback when sending messages
			const noop = () => { };
			wss.on("connection", (socket, req) => {
				const params = new URL("http://localhost" + req.url).searchParams;
				const sid = params.get("sid");
				const page = params.get("page");
				// Ignore duplicate connections:
				if (!!clients[page][sid])
				{
					socket.send(JSON.stringify({code:"duplicate"}));
					return;
				}
				clients[page][sid] = socket;
				if (page == "index")
				{
					// Send counting info
					const countings = {};
					for (const v of variants)
						countings[v.name] = Object.keys(clients[v.name]).length;
					socket.send(JSON.stringify({code:"counts",counts:countings}));
				}
				else
				{
					// Send to every client connected on index an update message for counts
					Object.keys(clients["index"]).forEach( k => {
						clients["index"][k].send(
							JSON.stringify({code:"increase",vname:page}), noop);
					});
					// Also notify potential opponents:
					// hit all clients which check if sid corresponds
					Object.keys(clients[page]).forEach( k => {
						clients[page][k].send(JSON.stringify({code:"connect",id:sid}), noop);
					});
					socket.on("message", objtxt => {
						let obj = JSON.parse(objtxt);
						switch (obj.code)
						{
							case "newchat":
								if (!!clients[page][obj.oppid])
								{
									clients[page][obj.oppid].send(
										JSON.stringify({code:"newchat",msg:obj.msg}), noop);
								}
								break;
							case "newmove":
								if (!!clients[page][obj.oppid])
								{
									clients[page][obj.oppid].send(
										JSON.stringify({code:"newmove",move:obj.move}), noop);
								}
								break;
							case "ping":
								if (!!clients[page][obj.oppid])
									socket.send(JSON.stringify({code:"pong",gameId:obj.gameId}));
								break;
							case "myname":
								// Reveal my username to opponent
								if (!!clients[page][obj.oppid])
								{
									clients[page][obj.oppid].send(JSON.stringify({
										code:"oppname", name:obj.name}));
								}
								break;
							case "lastate":
								if (!!clients[page][obj.oppid])
								{
									const oppId = obj.oppid;
									obj.oppid = sid; //I'm oppid for my opponent
									clients[page][oppId].send(JSON.stringify(obj), noop);
								}
								break;
							case "newgame":
								if (!!games[page])
								{
									// Start a new game
									const oppId = games[page]["id"];
									const fen = games[page]["fen"];
									delete games[page];
									const mycolor = Math.random() < 0.5 ? 'w' : 'b';
									socket.send(JSON.stringify(
										{code:"newgame",fen:fen,oppid:oppId,color:mycolor}));
									if (!!clients[page][oppId])
									{
										clients[page][oppId].send(
											JSON.stringify(
												{code:"newgame",fen:fen,oppid:sid,color:mycolor=="w"?"b":"w"}),
											noop);
									}
								}
								else
									games[page] = {id:sid, fen:obj.fen}; //wait for opponent
								break;
							case "cancelnewgame": //if a user cancel his seek
								delete games[page];
								break;
							case "resign":
								if (!!clients[page][obj.oppid])
									clients[page][obj.oppid].send(JSON.stringify({code:"resign"}), noop);
								break;
						}
					});
				}
				socket.on("close", () => {
					delete clients[page][sid];
					// Remove potential pending game
					if (!!games[page] && games[page]["id"] == sid)
						delete games[page];
					if (page != "index")
					{
						// Send to every client connected on index an update message for counts
						Object.keys(clients["index"]).forEach( k => {
							clients["index"][k].send(
								JSON.stringify({code:"decrease",vname:page}), noop);
						});
					}
					// Also notify potential opponents:
					// hit all clients which check if sid corresponds
					Object.keys(clients[page]).forEach( k => {
						clients[page][k].send(JSON.stringify({code:"disconnect",id:sid}), noop);
					});
				});
			});
		});
	});
}