# Description:
#   accede a wolfram alpha
#
# Configuration:
#   WOLFRAM_API_KEY - self explanatory
#
# Commands
#   hubot wolfram/wfa/quanto fa/calcola/compute ... - pone la domanda a Wolfram Alpha
#
# Author:
#   Enrico Fasoli (fazo96)
#

cheerio = require 'cheerio'

module.exports = (robot) ->
  robot.wquery = (input, key, callback) ->
    q = encodeURIComponent input
    url = 'http://api.wolframalpha.com/v2/query?input=' + q + '&appid=' + key
    robot.http(url).get() (err, res, body) ->
      if err then return callback err, {}

      $ = cheerio.load body, xmlMode: true
      if $('queryresult').attr('error') == 'true'
        return callback $('error').find('msg').text(), {}

      pods = ($('pod').map (_, pod) ->
        title: $(pod).attr 'title'
        primary: $(pod).attr('primary')?
        subpods: ($('subpod', $ pod).map (_, subpod) ->
          title: $(subpod).attr 'title'
          value: $('plaintext', $ subpod).text()
          image: $('img', $ subpod).attr 'src'
          ).get()
        ).get()

      if pods.length
        callback null, pods
      else
        callback 'la risposta da wolfram non è valida', []

  robot.respond /(?:calcola|quanto fa|compute|wfa|wolfram) (.+)/i, (res) ->
    wait = ['chiedo a wolfy', 'dammi un attimo', 'sto pensando',
            'fammi fare due conti', 'chiedo a wolfram']
    key = process.env.WOLFRAM_API_KEY
    if not key
      return res.send 'non ho le chiavi per Wolfram Alpha :('

    res.send (res.random wait) + '...'
    robot.wquery res.match[1], key, (err, result) ->
      if err then return res.send "c'è qualche problema: " + err

      parseSubPod = (subpod) -> subpod.value or subpod.image
      parsePod = (pod) ->
        '\n=== ' + pod.title + '\n' + pod.subpods.map(parseSubPod).join('\n')
      res.send (parsePod(pod) for pod in result).join('').trim()