{-# LANGUAGE Arrows, NoMonomorphismRestriction #-}
import ShadowLibrary.Core

import Text.XML.HXT.Core
import Text.XML.HXT.XPath
-- import Text.XML.HXT.Curl
import Data.List
import Data.List.Utils (replace)

import Text.Regex.Posix
import Text.Printf


extractRecords = extractLinksWithText "//div[@class='artifact-title']/a"  -- pary adres-tytuł
                 -- >>> second (arr $ replace "\r\n            " " ") -- czyścimy drugi element pary, czyli tytuł z niepotrzebnych białych znaków
                 -- >>> first (arr ((++"tr") . init))  -- modyfikujemy pierwszy element pary, czyli adres URL
                 -- >>> first (extractLinksWithText "//li/a[contains(@href,'.pdf')]") -- pobieramy stronę z adresu URL i wyciągamy linki z tej strony pasujące do wyrażenia XPathowego
                 -- ostatecznie wyjdą trójki ((adres URL, tytuł artykułu), tytuł rocznika)

extractPages = extractLinksWithText "//div[@class='pagination-masked clearfix top']//a[@class='next-page-link']" 

-- ... a tutaj te trójki przerabiamy do docelowej struktury ShadowItem
toShadowItem :: ((String, String), String) -> ShadowItem
toShadowItem ((url, articleTitle), yearlyTitle) =
  (defaultShadowItem url title) {
    originalDate = Just date,
    itype = "periodical",
    format = Just "pdf",
    finalUrl = url
    }
  where title = "Almanach Muszyny " ++ yearlyTitle ++ " " ++ (replace "\r\n" "" (replace "\r\n          " "" articleTitle))
        date = getDate url

getDate url =
  case url =~~ "/(19[0-9][0-9]|20[0-9][0-9])/" :: Maybe [[String]] of
    Just [[_, year]] -> year
    otherwise -> error $ "unexpected url: " ++ url

runExtractor url = runX $ (arr (const url) >>> setTraceLevel 1 >>> extractPages)

runDocumentsExtractor url = runX $ (arr (const url) >>> setTraceLevel 1 >>> extractRecords)

runExtractorMultiple (url, title) = runExtractor url

mapToUrl :: ([Char], [Char]) -> [Char]
mapToUrl (url, title) = url

merge [] ys = ys
merge (x:xs) ys = x:merge ys xs

addDimension array = [array]

withEmptyCheck current [] = do 
  publications <- runDocumentsExtractor current
  let publicationUrls = map mapToUrl publications
  return publicationUrls
  
withEmptyCheck current nextUrls = do
  let single = head nextUrls
  publications <- runDocumentsExtractor current
  let publicationUrls = map mapToUrl publications
  --print publicationUrls
  --TODO how to combine publications?
  --let mapped = map addDimension publications
  --print mapped
  --print current
  recursive <- getAllPages single
  --print recursive
  let results = merge publicationUrls recursive
  --print results
  return results

getAllPages url = do
  items <- runExtractor url
  let urls = map mapToUrl items
  results <- (withEmptyCheck url urls)
  return results


main = do
    let start = "https://pbsociety.org.pl/repository/discover?filtertype=has_content_in_original_bundle&filter_relational_operator=equals&filter=true"
    let shadowLibrary = ShadowLibrary {logoUrl=Nothing,
                                       lname="Polskie Towarzystwo Botaniczne",
                                       abbrev="PBSociety",
                                       lLevel=0,
                                       webpage=start}

    --items <- runExtractor start
    --let items2 = map mapToUrl items
    --items3 <- mapM runExtractor items2


    --let items3 = map runExtractor items2
    --extractItemsStartingFromUrl shadowLibrary start extractRecords2
    --map putStrLn items3
    --mapM_ (putStrLn . show) items
    --putStrLn items3

    results <- getAllPages start
    print results
    --print items