const fs = require("fs").promises
const path = require("path")
const crypto = require("crypto")
const express = require("express")
const multer = require("multer")
const session = require("cookie-session")
const expressPromiseRouter = require("express-promise-router")

const PASSWORD = "5e884898da28047151d0e56f8dc6292773603d0d6aabbdd62a11ef721d1542d8" // 'password'
const APP_ROOT = path.join(__dirname, "..")
const UPLOAD_DIR = path.join(APP_ROOT, "uploads")

const upload = multer({
    storage: multer.memoryStorage(),
    limits: {
        fileSize: 2**24 // 16MiB
    }
})

const server = express()

server.use(session({
    secret: "SESSION SECRET",
    cookie: {
        maxAge: 1000 * 60 * 60 * 24 * 7 // one week in milliseconds
    },
    resave: false,
    saveUninitialized: false
}))
server.use(express.static(UPLOAD_DIR))
server.use("/dist", express.static(path.join(APP_ROOT, "dist"), {
}))
server.use(express.urlencoded({
    extended: false
}))

const app = expressPromiseRouter()

app.get("/", async (req, res) => {
    res.render("index", { title: "Index" })
})

// login form
app.get("/login", (req, res) => res.render("login", { title: "Login" }))
app.post("/login", (req, res) => { // validate the login
    if (!req.body.password) return res.status(400).send("Missing password")
    if (crypto.createHash("sha256").update(req.body.password).digest("hex") !== PASSWORD) return res.status(403).send("Invalid password")
    req.session.authed = true
    req.session.save()
    res.redirect("/upload")
})

app.use("/upload", (req, res, next) => { // redirect to login if not authenticated
  if (!req.session || !req.session.authed) return res.redirect("/login")
  next()
})
app.get("/upload", (req, res) => res.render("upload", { title: "Upload" }))
app.post("/upload", upload.single("file"), async (req, res) => { // handle file uploads
    if (!req.file) return res.status(400).send("Missing file")
    const newFilename = `${new Date().getTime()}${path.extname(req.file.originalname)}`
    await fs.writeFile(path.join(UPLOAD_DIR, newFilename), req.file.buffer)
    res.redirect(`/${newFilename}`)
})

server.use(app)

server.set("view engine", "pug")
server.listen(3000, () => console.log("running"))