# Description:
#   deep fry an image
#
# Commands:
#   hubot deepfry/friggi[mi] <url>
#
# Dependencies:
#   "async": "^1.4.2",
#   "hubot-matrix": "rnhmjoj/hubot-matrix",
#   "needle": "^0.10.0",
#
# Configuration:
#   None
#
# Author:
#   Michele Guerini Rocco (rnhmjoj)

ne    = require 'needle'
async = require 'async'
gm    = require 'gm'
url   = require 'url'

module.exports = (robot) ->
  # utilities
  concat = (x) -> [].concat.apply([], x)
  init   = (x) -> (f) -> f(null, x)
  times  = (n, x) -> x for i in [1..n]
  rand   = (min, max) -> Math.random() * (max - min) + min

  # effects
  compress = (image, callback) ->
    gm(image)
    .noProfile()
    .noise('uniform')
    .quality(rand(30,80))
    .noise('uniform')
    .toBuffer callback

  resize = (image, callback) ->
    gm(image)
    .scale('95%')
    .scale('105%')
    .toBuffer callback

  colorize = (image, callback) ->
    gm(image)
    .modulate(rand(100,110), rand(100,150))
    .toBuffer callback

  deepFry = (res, image) ->
    script = concat [
      init(image),
      resize,
      colorize
      times(50, compress),
    ]

    async.waterfall script, (err, image) ->
      if err?
        robot.logger.warning "frying failed:\n#{err}"
        return res.send 'scusa, si è rotta la friggitrice.'

      # send image
      robot.logger.info 'image fried successfully'
      robot.adapter.sendImage
        room: res.message.room
        , image, 'fried.jpeg', ->
        res.reply res.random [ 'meme fritto per te.', 'eccoti servito.']


  robot.respond /(?:deepfry|friggi(?:mi)?) (questo|.+)/i, (res) ->
    if not url.parse(res.match[1]).hostname
      return res.send res.random [ 'non si usa così.', 'è un url questo?', 'cosa?' ]
    imageURL = res.match[1]

    # supported image mime types
    accepted = ['image/jpeg', 'image/png', 'image/tiff']

    # fetch headers
    ne.head imageURL, follow_max: 5, (err, re) ->
      if err?
        robot.logger.warning "headers download failed:\n#{err}"
        return res.send 'non riesco ad aprire il link.'

      mimetype = re.headers['content-type'].split(';')[0]
      if not (mimetype in accepted)
        robot.logger.info 'url is not an image'
        return res.send "non è un'immagine questo!"

      # download and process
      robot.logger.info 'downloading image...'
      ne.get imageURL, follow_max: 5, (err, re, body) ->
        robot.logger.info 'image downloaded'
        deepFry res, body