var fs = require('fs')
var google = require('googleapis')
var googleAuth = require('google-auth-library')

function AWFeedback (options) { if (!(this instanceof AWFeedback)) return new AWFeedback(options)
  options = options || {}
  if (!options.express)
    throw new Error('Express not provided to AWFeedback');
  if (!options.config)
    throw new Error('Configuration not provided to AWFeedback');

  var express = options.express
  var router = express.Router()
  var config = options.config
  var db = options.db

  var credentials = JSON.parse( fs.readFileSync(config.credentials) )
  var token = JSON.parse( fs.readFileSync(config.token) )

  var clientSecret = credentials.installed.client_secret
  var clientId = credentials.installed.client_id
  var redirectUrl = credentials.installed.redirect_uris[0]
  var gauth = new googleAuth()
  var auth = new gauth.OAuth2(clientId, clientSecret, redirectUrl)
  auth.credentials = token

  var sheets = google.sheets('v4');

  router.get('/index', function (req, res) {
    sheets.spreadsheets.values.get({
      auth: auth,
      spreadsheetId: config.spreadsheet,
      range: 'Form Responses 1!A2:F',
    }, function(err, response) {
      if (err) {
        res.json([])
        return
      }
      var rows = response.values;
      if (rows.length == 0) {
        res.json([])
      } else {
        var parsed = rows.filter( row => row[4] === 'x' && row[5] === 'x' )
           		           .map( row => [ row[0], row[1], row[3] ] )
        res.json(parsed)
      }
    });
  })

  router.post('*', function (req, res) {
    throw new Error('AWFeedback POST requests not implemented')
  })

  this._router = router
}

AWFeedback.prototype.middleware = function () {
  return this._router
}

module.exports = AWFeedback