import express from 'express'
import cookieParser from 'cookie-parser'
import { newGame, dropPiece, toJson, isWaiting, joinGame } from './connect4.js'

const app = express()
app.use(cookieParser())
const port = 3001

/** Retrieve the user's identifier from the cookies, or set a new one. */
function getUserId(req, res) {
    let userid = req.cookies.userid
    if (userid == undefined) {
        userid = crypto.randomUUID()
        res.cookie('userid', userid)
    }
    return userid
}

/* The empty path will join a waiting game or create a fresh one. 
 * Afterwards, the request is redirected to /:gameid/. */
app.get('', (req, res) => {
    const userid = getUserId(req, res)
    // First attempt to find a waiting game and join that.
    for (let game of Object.values(games)) {
        if (isWaiting(game, userid)) {
            joinGame(game, userid)
            console.log(`Game ${game.id} randomly joined by ${userid}`)
            res.redirect(`${game.id}/`)
            return
        }
    }
    // No waiting game found - create a new one
    let game = newGame(nextGameId)
    games[nextGameId] = game
    nextGameId += 1
    
    joinGame(game, userid)
    console.log(`Game ${game.id} started by ${userid}`)
    res.redirect(`${game.id}/`)
})