"use strict";

const path = require("path");
const express = require("express");
const expressSSE = require("express-sse");
const chokidar = require("chokidar");
const debounce = require("debounce");

const processManager = require("../process-manager");

// TODO: Add a 'reloading...' indicator when re-running the process, since it may be slow -- as well as an "error occurred" indicator

module.exports = function ({ absoluteProcessPath, processArguments }) {
	let lastData = "null";
	
	let sse = new expressSSE();
	
	let nodeProcess = processManager(absoluteProcessPath, processArguments, {
		onOutput: (output) => {
			lastData = {
				type: "output",
				payload: output
			};

			sse.send(lastData);
		},
		onError: (error) => {
			lastData = {
				type: "error",
				payload: error
			};

			sse.send(lastData);
		},
		onStart: () => {
			sse.send({ type: "running" });
		}
	});
	
	nodeProcess.start();

	chokidar
		.watch(process.cwd())
		.on("all", debounce((_event, path) => {
			nodeProcess.restart(path);
		}, 500));
	
	let app = express();
	
	app.use(express.static(path.join(__dirname, "public")));
	
	app.get("/", (req, res) => {
		res.sendFile(path.join(__dirname, "public/index.html"));
	});
	
	app.get("/initial_data", (req, res) => {
		res.send(lastData);
	});
	
	app.get("/stream", sse.init);
	
	return app;
};