const Express = require('express')
const bdb = require('bdb.js')
const posts = bdb.load('posts.json', 1)

const webname = 'TheForum'

const server = new Express()

server.set('view engine', 'ejs')

function replace(req, regex, repl) {
    const url = req.url.replaceAll(regex, repl)
    console.log(url)
    const parsedUrl = new URL('http://localhost' + url)
    req.url = url
    req.originalUrl = url
    req.path = parsedUrl.pathname
    req.search = parsedUrl.search
    req._parsedUrl = parsedUrl
    const query = {}
    for(const entry of parsedUrl.searchParams) {
        query[entry[0]] = entry[1]
    }
    req.query = query
}

server.use(function replacer(req, res, next) {
    replace(req, /^\/post\/([0-9]+)_?/g, '/post?id=$1')
    replace(req, /^\/comment\/([0-9_]+)\/([0-9_]*)(\?(.*))?/g, '/comment?id=$1&comment=$2&$4')
    next()
})


server.get('/', function get(req, res) {
    if(req.query.name && req.query.title && req.query.content) {
        posts.push({timestamp: new Date().getTime(), author: req.query.name, title: req.query.title, content: req.query.content.replaceAll('\r\n', '\n'), comments: []})
        res.redirect('/')
        return
    }
    let mainPage = {author: webname, title: 'All posts', content: 'These are all the posts on the board:', comments: []}
    for (let i = 0; i < posts.length && i < 2000; i++) {
        mainPage.comments.push({timestamp: posts[i].timestamp, author: posts[i].author, title: posts[i].title, content: posts[i].content, comments: []}) 
    }
    res.render('post.ejs', {post: mainPage, postid: '-1', webname: webname, comment: ''})
})
server.get('/post', function get(req, res) {
    if(req.query.id) {
        let id = req.query.id
        if(posts[id]) {
            res.render('post.ejs', {post: posts[id], postid: id, webname: webname, comment: null})
        }
    }
})
server.get('/comment', function get(req, res) {
    if(req.query.id) {
        let id = req.query.id
        let comment = req.query.comment 
        if(posts[id]) {
            let cid = ''
            function recurse(post) {
                console.log(String(cid) + ' ' + comment)
                if(String(cid) === comment) {
                    if(req.query.name && req.query.title && req.query.content) { 
                        post.comments.push({timestamp: new Date().getTime(), author: req.query.name, title: req.query.title, content: req.query.content.replaceAll('\r\n', '\n'), comments: []})
                        res.redirect(`/post/${id}`)
                        cid = -1
                    }
                    return true
                }
                for(let i = 0; i < post.comments.length; i++) {
                    const pid = cid
                    cid += i + '_'
                    if(recurse(post.comments[i]))
                        return true
                    cid = pid
                }
                return false
            }
            const f = recurse(posts[id]);
            if(f && cid == -1)
                return
            if(f) {
                res.render('post.ejs', {post: posts[id], postid: id, webname: webname, comment: cid})
            }
            else {
                if(req.query.name && req.query.title && req.query.content) { 
                    posts[id].comments.push({timestamp: new Date().getTime(), author: req.query.name, title: req.query.title, content: req.query.content.replaceAll('\r\n', '\n'), comments: []})
                    res.redirect(`/post/${id}`)
                }
                else
                    res.render('post.ejs', {post: posts[id], postid: id, webname: webname, comment: ''})
            }
        }
    }
    else
        res.send("err1")
})

let PORT = process.argv[2]
if(!PORT) PORT = process.env.PORT
if(!PORT) PORT = 8080
server.listen(Number(PORT), () => console.log(PORT))