module  Data.Carbonara.Read where

import           Data.Carbonara.Char (isNotDigit) --carbonara
import           Data.Carbonara.String (replaceStrOnce) 


import           Data.Char (isDigit, toLower, toUpper)
import           Data.Maybe (fromJust, isJust)
import           Data.Time.Calendar (Day, fromGregorian)  --time

import           Text.Printf (printf)
import           Text.Read (readMaybe)

import           Data.List (intercalate)
import           Data.List.Split (chunksOf)  --split




readB :: Show a => a -> Maybe Bool
readB x 
  | take 5 str `elem` ["just ", "right"] = readMaybe $ drop 5 str
  | otherwise = readMaybe str
  where str = replaceStrOnce "true" "True" . replaceStrOnce "false" "False" .
              map toLower . filter (`notElem` ['"','\'']) . show $ x
-- Test cases:
-- Just True :  from these input: True, "True", " TRUE", " 'true' ", Just True, Just "tURe", Right True", Right "\'true" 
-- Just False : from all input: False, "False", " 'FALSE", "faLSe ", Just False, Just "false ", Right "FALSe", Right "'false" 
-- Nothing :    from all input: Nothing, "Tr ue", "Fal se", Just "T RUE", Right "falsee" 


readC :: Show a => a -> Maybe Char
readC x
  | show x `elem` ["'\\''" , "\"'\"" , "Just '\\''" , "Just \"'\"" , "Right '\\''", "Right \"'\""] = Just '\''
  | show x `elem` ["'\"'" , "Just '\"'" , "Right '\"'" , "\"\\\"\"" , "Just \"\\\"\"" , "Right \"\\\"\"" ] = Just '"'
  | take 5 str == "Just " = readMaybe . addSingleQuote . drop 5 $ str
  | take 6 str == "Right " = readMaybe . addSingleQuote . drop 6 $ str
  | otherwise = readMaybe . addSingleQuote $ str
  where str = filter (`notElem` ['"','\'']) . show $ x
        addSingleQuote s = ('\'':s) ++ "\'"


readD :: Show a => a -> Maybe Double
readD x
  | take 5 s == "Just "  = readD . drop 5 $ s
  | take 6 s == "Right " = readD . drop 6 $ s
  | take 1 s == "."      = readMaybe ('0': s)
  | take 2 s == "-."     = readMaybe . ("-0" ++) . drop 1 $ s
  | otherwise = readMaybe s
  where s = filter (`notElem` ['\\', '"', '\'', ',', '%', '+', '$', '¢', '£', '¥', '€']) . show $ x


readDMY :: Show a => a -> Maybe Day
readDMY x
  | isJust y && isJust m && isJust d = Just $ fromGregorian (fromJust y) (fromJust m) (fromJust d)
  | otherwise = Nothing
  where s = dropWhile isNotDigit . show $ x
        d = readInt . takeWhile isDigit $ s
        m = readInt . takeWhile isDigit . dropWhile isNotDigit . dropWhile isDigit $ s
        y = readI . takeWhile isDigit . dropWhile isNotDigit . dropWhile isDigit .
            dropWhile isNotDigit . dropWhile isDigit $ s

readMDY :: Show a => a -> Maybe Day
readMDY x
  | isJust y && isJust m && isJust d = Just $ fromGregorian (fromJust y) (fromJust m) (fromJust d)
  | otherwise = Nothing
  where s = dropWhile isNotDigit . show $ x
        m = readInt . takeWhile isDigit $ s
        d = readInt . takeWhile isDigit . dropWhile isNotDigit . dropWhile isDigit $ s
        y = readI . takeWhile isDigit . dropWhile isNotDigit . dropWhile isDigit .
            dropWhile isNotDigit . dropWhile isDigit $ s


readYMD :: Show a => a -> Maybe Day
readYMD x
  | isJust y && isJust m && isJust d = Just $ fromGregorian (fromJust y) (fromJust m) (fromJust d)
  | otherwise = Nothing
  where s = dropWhile isNotDigit . show $ x
        y = readI . takeWhile isDigit $ s
        m = readInt . takeWhile isDigit . dropWhile isNotDigit . dropWhile isDigit $ s
        d = readInt . takeWhile isDigit . dropWhile isNotDigit . dropWhile isDigit .
            dropWhile isNotDigit . dropWhile isDigit $ s






readDStr :: Show a => a -> Maybe String
readDStr x = Just (++) <*> integer_part <*> decimal_part
  where s            = printf "%.2f" <$> readD x
        integer_part = reverse . intercalate "," . chunksOf 3 . reverse . takeWhile (/= '.') <$> s
        decimal_part = dropWhile (/= '.') <$> s 
-- | with 2 decimal place


readI :: Show a => a -> Maybe Integer
readI x
  | take 5 s `elem` ["Just ", "Right"] = readMaybe . drop 5 $ s
  | otherwise = readMaybe s
  where s = filter (`notElem` ['\\', '"', '\'', ',', '%', '+', '$', '¢', '£', '¥', '€']) . show $ x



readInt :: Show a => a -> Maybe Int
readInt x
  | take 5 s `elem` ["Just ", "Right"] = readMaybe . drop 5 $ s
  | otherwise = readMaybe s
  where s = filter (`notElem` ['\\', '"', '\'', ',', '%', '+', '$', '¢', '£', '¥', '€']) . show $ x

      
readIStr :: Show a => a -> Maybe String
readIStr x = integer_part
                      where s = printf "%.0f" <$> readD x
                            integer_part = reverse . intercalate "," . chunksOf 3 . reverse <$> s



readLargeNum :: Show a => a -> Maybe Double
readLargeNum x
  | take 5 s == "Just "  = readLargeNum . drop 5 $ s
  | take 6 s == "Right " = readLargeNum . drop 6 $ s
  | lastchar == "M" = (*1000000) <$> readMaybe (init s)
  | lastchar == "B" = (*1000000000) <$> readMaybe (init s)
  | lastchar == "T" = (*1000000000000) <$> readMaybe (init s)
  | otherwise = Nothing
  where s = filter (`notElem` ['\\', '"', '\'', ',', '%', '+', '$', '¢', '£', '¥', '€']) . show $ x
        lastchar = map toUpper . take 1 . reverse $ s


readS :: Show a => a -> Maybe String
readS x
  | s == "Nothing" = Nothing
  | take 5 s == "Just " = readMaybe . addDoubleQuote . drop 5 $ s
  | take 6 s == "Right " = readMaybe . addDoubleQuote . drop 6 $ s
  | otherwise = readMaybe . addDoubleQuote $ s
  where s = filter (`notElem` ['"', '\'', ',', '%', '+', '$', '¢', '£', '¥', '€', '\\', '[', ']']) . show $ x
        addDoubleQuote s = ('"':s) ++ ['"']