const express = require("express");
const path = require("path");
const fileUpload = require("express-fileupload");
const basicAuth = require("express-basic-auth");
const fs = require("fs");
const app_conf = require("./app/config/app.conf.js");

const public_routes = require('./app/routes/public_routes');
const private_routes = require('./app/routes/private_routes');

const logger = require("./app/utils/logger.util.js");

const app = express();
var shutting_down = false;

/*
 * Static middleware - serve css and js files to public
 */
app.use(express.json());
app.use(fileUpload({
    limits: { fileSize: 102400 },
    useTempFiles: true,
    tempFileDir: path.join(__dirname, app_conf.temp_directory)
}));

app.use("/", public_routes);

app.use("/app", basicAuth({
    users: {
        [app_conf.username]: app_conf.password
    },
    challenge: true
}), private_routes);

/*
 * Initialise ExpressJS
 * Using ejs to pass variables from ExpressJS to HTML pages.
 */
app.set("view engine", "ejs");
app.set("views", path.join(__dirname, app_conf.views_directory));
const server = app.listen(app_conf.port, (error) => {
    logger.info("Starting Database Editor.");


    fs.rm(path.join(__dirname, app_conf.temp_directory, "/."), { recursive: true }, (error) => {
        if (error == null) {
            logger.info("Removed temp directory.");
        } else if (error.code === "ENOENT") {
            logger.info("Temp directory not found.");
        } else {
            logger.error(error.message);
        }
    });

    if (error) {
        logger.error(error.message);
        shutdown();
    } else {
        logger.info(`Listening to port ${app_conf.port}.`);
    }
})

/*
 * Handle Ctrl+C to shutdown gracefully
 */
process.on("SIGINT", () => {
    if (shutting_down) {
        logger.emerg("Shutting down forcefully.");
        process.exit(-1);
    } else {
        shutdown();
    }
});

/*
 * This function shuts the server down
 */
function shutdown() {
    shutting_down = true;

    server.close(() => {
        logger.info("Shutting down server.");
    });
}