module Service.AdListener
  ( start
  ) where

import           Control.Concurrent  (threadDelay)
import qualified Data.Text.IO        as T
import           Prelude             hiding (error)

import           Conf                (Conf)
import qualified Conf
import qualified FetchAd
import           Model.Ad            (Ad)
import qualified Model.Ad            as Ad
import           Model.Mail          (Mail (Mail))
import           Model.URL           (URL)
import qualified Service.MailService as MailService
import qualified Utils.Time          as TimeUtils
import qualified View.Ad             as Ad

start :: Conf -> IO ()
start conf = do
  ads <- fetchAds conf
  let newURLs = map Ad.url ads
  T.putStrLn "Listening to new ads…"
  waitListenInterval conf
  listenToNewAdsWithViewedURLs conf newURLs

listenToNewAdsWithViewedURLs :: Conf -> [URL] -> IO ()
listenToNewAdsWithViewedURLs conf viewedURLs = do
  ads <- fetchAds conf
  let (newURLs, newAds) = Ad.getNewAds viewedURLs ads
  time <- TimeUtils.getCurrentFormattedTime
  if not (null newAds)
    then
      do
        _ <- T.putStrLn (Ad.renderConsoleAds time newAds)
        if Conf.devMode conf
          then return ()
          else sendMail conf newAds
    else
      return ()
  waitListenInterval conf
  listenToNewAdsWithViewedURLs conf (viewedURLs ++ newURLs)

fetchAds :: Conf -> IO [Ad]
fetchAds conf = do
  leboncoinAds <- FetchAd.leboncoin (Conf.leboncoinUrls conf)
  ouestFranceAds <- FetchAd.ouestFrance (Conf.ouestFranceUrls conf)
  seLogerAds <- FetchAd.seLoger (Conf.seLogerUrls conf)
  let results = leboncoinAds ++ ouestFranceAds ++ seLogerAds
  if null results
    then T.putStrLn "Parsed 0 results!"
    else return ()
  return results

sendMail :: Conf -> [Ad] -> IO ()
sendMail conf ads =
  let (title, plainBody) = Ad.renderAds ads
      mail = Mail (Conf.mailFrom conf) (Conf.mailTo conf) title plainBody
  in  MailService.send mail >> return ()

waitListenInterval :: Conf -> IO ()
waitListenInterval = threadDelay . (*) 1000000 . round . Conf.listenInterval