const readers = require('./url_to_markdown_readers.js');
const processor = require('./url_to_markdown_processor.js');
const validURL = require('@7c/validurl');
const express = require('express');
const rateLimit = require('express-rate-limit');
const JSDOM = require('jsdom').JSDOM;
const port = process.env.PORT;
const app = express();

const rateLimiter = rateLimit({
	windowMs: 30 * 1000,
	max: 5,
	message: 'Rate limit exceeded',
	headers: true
});

app.use(rateLimiter);

app.use(express.urlencoded({
  extended: true,
  limit: '10mb'
}));

function send_headers(res) {
	res.header("Access-Control-Allow-Origin", '*');
	res.header("Access-Control-Allow-Methods", 'GET, POST');
 	res.header("Access-Control-Expose-Headers", 'X-Title');
 	res.header("Content-Type", 'text/markdown');
}

function read_url(url, res, inline_title, ignore_links) {
		reader = readers.reader_for_url(url);
		send_headers(res);
		reader.read_url(url, res, inline_title, ignore_links);	
}

app.get('/', (req, res) => {
	const url = req.query.url;
	const title = req.query.title;
	const links = req.query.links;
	let inline_title = false;
	let ignore_links = false;
	if (title) {
		inline_title = (title === 'true');
	}
	if (links) {
		ignore_links = (links === 'false');
	}
	if (url && validURL(url)) {
		read_url(url, res, inline_title, ignore_links);		
	} else {
		res.status(400).send("Please specify a valid url query parameter");
	}
});

app.post('/', function(req, res) {
	const html = req.body.html;
	const url = req.body.url;
	const links = req.query.links;
	const title = req.query.title;
	let ignore_links = false;
	let inline_title = false;
	if (title) {
		inline_title = (title === 'true');
	}
	if (links) {
		ignore_links = (links === 'false');
	}
	if (readers.ignore_post(url)) {
		read_url(url, res, inline_title, ignore_links);
		return;
	}
	if (!html) {
		res.status(400).send("Please provide a POST parameter called html");
	} else {	  	
		try {
			let document = new JSDOM(html);
			let markdown = processor.process_dom(url, document, res, inline_title, ignore_links);
			send_headers(res);
			res.send(markdown);
		 } catch (error) {
		 res.status(400).send("Could not parse that document");
		}
	}

});

app.listen(port, () => {	
})