#!/usr/bin/env node

// Usage ./third.js < VERY_LARGE_FILE

const { Sema } = require('async-sema');
const readline = require('readline');

const rl = readline.createInterface({
	input: process.stdin,
	output: process.stdout,
	terminal: false
});

function pause() {
	console.log('Pausing the stream');
	rl.pause();
}

function resume() {
	console.log('Resuming the stream');
	rl.resume();
}

const s = new Sema(5, { pauseFn: pause, resumeFn: resume });

async function parse(line) {
	await s.acquire();

	console.log(line);

	s.release();
}

rl.on('line', line => {
	parse(line).catch(console.error);
});