const showdown = require('showdown')
const express = require('express')
const fs = require('fs')

const siteMap = require('./siteMap')

// ========================================
// == compiles ============================
// ========================================

const MDCompile = new showdown.Converter({tables: true})

function compileMD(file, fn){
  fs.readFile(file, 'utf-8', function(err, markdown){
    if(err){
      console.error("ERROR: could not read file:", file)
      if(typeof fn == 'function')
        fn(-1)
    }
    html = MDCompile.makeHtml(markdown);
    if(typeof fn == 'function')
      fn(html)
    else
      fs.writeFile(fn, html, function(err){
        if(err)
          console.error(err)
      })
  })
}

function compilePDF(file, fn){
  fs.readFile(file, 'utf-8', function(err, pdf){
    if(err){
      console.error("ERROR: could not read file:", file)
      if(typeof fn == 'function')
        fn(-1)
    }
    return fn("<h1>PDF not supoted yet</h1>")
    // pdf = MDCompile.makeHtml(markdown);
    // if(typeof fn == 'function')
    //   fn(html)
    // else
    //   fs.writeFile(fn, html, function(err){
    //     if(err)
    //       console.error(err)
    //   })
  })
}

// ========================================
// == webserver ===========================
// ========================================

const app = express()
app.set('view engine', 'ejs');
app.set('views', __dirname + '/views')

app.use('/img', function(req, res, next){
  res.sendFile(__dirname + '/img' + req.path)
})

app.use('/:vak/static', renderStatic)
app.use('/:vak/:page', renderPage)
app.use('/:vak', renderVak)
app.use('/', renderIndex)
app.use(render404)

function onError404(req, res, next){
  return function(err){
    render404(req, res, next)
  }
}

function renderStatic(req, res, next){
  if(typeof siteMap[req.params.vak] == 'undefined') return next();
  vak = siteMap[req.params.vak]

  dir = __dirname.split('/'); dir.pop() // remove dir of this code
  dir = `${dir.join('/')}/${vak.title}/notes/static${req.path}`

  res.sendFile(dir, onError404(req, res, next))
}

function renderPage(req, res, next){
  if(typeof siteMap[req.params.vak] == 'undefined') return next();
  vak = siteMap[req.params.vak]

  if(typeof vak.pages[req.params.page] == 'undefined') return next();
  page = vak.pages[req.params.page]


  compileMD(page.file, function(html){
    if(typeof html != 'string'){ return next() }

    res.render('mainV2', {
      siteMap,
      title: "notes",
      topNav: vak.pages,
      vak: req.params.vak,
      page: req.params.page,
      main: html
    })
  })
}

function renderVak(req, res, next){
  if(typeof siteMap[req.params.vak] == 'undefined') return next();
  vak = siteMap[req.params.vak]

  if(vak.index == null){
    res.render('mainV2', {
      siteMap,
      title: "notes",
      topNav: vak.pages,
      vak: req.params.vak,
      main: `<h1>${vak.title}</h1>`
    })
  }else{
    compileMD(vak.index, function(html){
      if(typeof html != 'string'){ return next() }

      res.render('mainV2', {
        siteMap,
        title: "notes",
        topNav: vak.pages,
        vak: req.params.vak,
        main: html
      }, onError404(req, res, next))
    })
  }
}

function renderIndex(req, res, next){
  res.render('mainV2', {
    siteMap,
    title: "notes",
    topNav: siteMap,
    main: "<h1>Hoi</h1>"
  }, onError404(req, res, next))
}

function render404(req, res, next){
  res.status(404)
  res.render('mainV2', {
    siteMap,
    title: "notes",
    topNav: vak.pages,
    vak: req.params.vak,
    main: "<h1>404 - Page not found</h1>"
  }, (err) => {
    if(err){
      res.send("<h1>404 - Page not found</h1>")
    }
  })
}

app.listen(8081, ()=>{console.log("server started")})