import { logger } from "@coder/logger"
import express, { Express } from "express"
import { promises as fs } from "fs"
import http from "http"
import * as httpolyglot from "httpolyglot"
import { DefaultedArgs } from "./cli"
import { handleUpgrade } from "./wsRouter"

/**
 * Create an Express app and an HTTP/S server to serve it.
 */
export const createApp = async (args: DefaultedArgs): Promise<[Express, Express, http.Server]> => {
 const app = express()

 const server = args.cert
 ? httpolyglot.createServer(
 {
 cert: args.cert && (await fs.readFile(args.cert.value)),
 key: args["cert-key"] && (await fs.readFile(args["cert-key"])),
 },
 app,
 )
 : http.createServer(app)

 await new Promise<http.Server>(async (resolve, reject) => {
 server.on("error", reject)
 if (args.socket) {
 try {
 await fs.unlink(args.socket)
 } catch (error) {
 if (error.code !== "ENOENT") {
 logger.error(error.message)
 }
 }
 server.listen(args.socket, resolve)
 } else {
 // [] is the correct format when using :: but Node errors with them.
 server.listen(args.port, args.host.replace(/^\[|\]$/g, ""), resolve)
 }
 })

 const wsApp = express()
 handleUpgrade(wsApp, server)

 return [app, wsApp, server]
}

/**
 * Get the address of a server as a string (protocol *is* included) while
 * ensuring there is one (will throw if there isn't).
 */
export const ensureAddress = (server: http.Server): string => {
 const addr = server.address()
 if (!addr) {
 throw new Error("server has no address")
 }
 if (typeof addr !== "string") {
 return `http://${addr.address}:${addr.port}`
 }
 return addr
}