This commit is contained in:
Daniel Flanagan 2022-10-11 13:42:34 -05:00
parent 95cee18537
commit e0a15d5333
Signed by untrusted user: lytedev-divvy
GPG Key ID: 6D69CEEE4ABBCD82
1 changed files with 60 additions and 97 deletions

157
2.ts
View File

@ -1,108 +1,71 @@
import { readLines } from "https://deno.land/std@0.157.0/io/buffer.ts";
import { BufReader } from "https://deno.land/std@0.157.0/io/buffer.ts";
import { ByteSet } from "https://deno.land/x/bytes@1.0.3/mod.ts";
const QUERY_SIZE = 9;
const PORT = 5588;
console.log(`Starting TCP listener on on 0.0.0.0:${PORT}`);
const clients = new Map<Deno.Conn, string>();
const listener = Deno.listen({ port: 5588 });
const tEnc = new TextEncoder();
console.log(`Listening on port ${PORT}`);
async function chatSession(conn: Deno.Conn) {
try {
let myNick: string | null = null;
await sendPrompt(conn);
for await (const line of readLines(conn)) {
console.debug("Received line:", line);
const message = line.trim();
if (myNick == null) {
if (isLegalNick(message)) {
myNick = message;
await join(myNick, conn);
} else {
console.error("Illegal nick:", message);
break;
}
} else {
const conns: Deno.Conn[] = [];
for (const themConn of clients.keys()) {
if (themConn != conn) conns.push(themConn);
}
await send(conns, `[${myNick}] ${message}`);
}
}
} finally {
if (clients.has(conn)) {
try {
await disconnect(conn);
} catch (err) {
console.error("Failed to disconnect:", err);
}
}
try {
if (conn.writable) {
send(conn, "You are being disconnected...");
}
} catch (err) {
console.error("Failed to send disconnect notice:", err);
}
}
try {
conn.close();
} catch (err) {
console.error("Failed to close connection:", err);
}
}
async function send(
connsArg: Deno.Conn | Array<Deno.Conn>,
text: string,
) {
const conns = !Array.isArray(connsArg) ? [connsArg] : connsArg;
const messages: Promise<number>[] = [];
const bytes = tEnc.encode(text + "\n");
conns.forEach((conn) => messages.push(conn.write(bytes)));
return await Promise.all(messages);
}
const broadcast = async (text: string) => await send([...clients.keys()], text);
const LEGAL_NICK_REGEXP = /^[a-z0-9]+$/i;
const isLegalNick = (nick: string) => {
console.debug(
`Checking nick: ${nick} (Bytes: ${tEnc.encode(nick)})`,
);
return LEGAL_NICK_REGEXP.exec(nick) != null;
};
const sendPrompt = async (conn: Deno.Conn) => {
console.debug("Sending prompt...");
return await send(conn, "Who you be?");
};
async function join(myNick: string, conn: Deno.Conn) {
const userList: string[] = [];
clients.forEach((nick, _) => userList.push(nick));
await broadcast(`* ${myNick} joined`);
clients.set(conn, myNick);
await send(conn, `* users: ${userList.join(", ")}`);
}
async function disconnect(conn: Deno.Conn) {
const myNick = clients.get(conn);
clients.delete(conn);
await broadcast(`* ${myNick} left`);
}
for await (const conn of Deno.listen({ port: PORT })) {
for await (const conn of listener) {
console.log("Connection established:", conn.remoteAddr);
try {
chatSession(conn);
meansToAnEnd(conn);
} catch (e) {
console.error(
"Exception occurred during chat session:",
conn.remoteAddr,
e,
);
console.error(conn.remoteAddr, e);
}
console.log("Connection closed:", conn.remoteAddr);
}
async function meansToAnEnd(conn: Deno.Conn) {
try {
const prices = [];
for await (const query of queries(conn)) {
if (query == null) break;
const bs = ByteSet.from(query, "big");
const queryChar = String.fromCharCode(bs.read.uint8());
const a1 = bs.read.int32();
const a2 = bs.read.int32();
if (queryChar == "I") {
prices.push([a1, a2]);
} else if (queryChar == "Q") {
let numMatches = 0;
let sum = 0;
for (const [ts, price] of prices) {
if (ts < a1 || ts > a2) continue;
numMatches++;
sum += price;
}
let result = Math.floor(sum / numMatches);
if (isNaN(result)) result = 0;
console.log(
conn.remoteAddr,
`Result for ${prices.length} prices: ${sum} / ${numMatches} = ${result}`,
);
const response = new ByteSet(4, "big");
response.write.int32(result);
conn.write(response.buffer);
}
}
console.log("Done!");
} catch (err) {
console.error("Error processing query:", err);
}
}
function queries(conn: Deno.Conn) {
return {
async *[Symbol.asyncIterator]() {
const b = new Uint8Array(9);
const reader = new BufReader(conn, QUERY_SIZE);
try {
while (await reader.readFull(b) != null) {
yield b;
}
} catch (err) {
console.error("Error receiving query:", err);
}
},
};
}