{-# LANGUAGE BangPatterns        #-}
{-# LANGUAGE DataKinds           #-}
{-# LANGUAGE MultiWayIf          #-}
{-# LANGUAGE OverloadedStrings   #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TupleSections       #-}
{-# LANGUAGE TypeApplications    #-}

module App.Commands.RangeJoin
  ( cmdRangeJoin
  ) where

import App.Char
import App.Commands.Options.Parse
import Control.Lens
import Control.Monad.IO.Class       (liftIO)
import Control.Monad.Trans.Resource
import Data.Generics.Product.Any
import Data.Maybe                   (fromMaybe, mapMaybe)
import Data.Word
import Options.Applicative          hiding (columns)
import Text.Read                    (readMaybe)

import qualified App.Commands.Options.Type              as Z
import qualified App.Data.RangeJoinColumn               as Z
import qualified App.IO                                 as IO
import qualified Data.ByteString.Builder                as B
import qualified Data.ByteString.Lazy                   as LBS
import qualified Data.List                              as L
import qualified Data.Text                              as T
import qualified Data.Text.Encoding                     as T
import qualified Data.Vector                            as DV
import qualified HaskellWorks.Data.Dsv.Lazy.Cursor      as SVL
import qualified HaskellWorks.Data.Dsv.Lazy.Cursor.Lazy as SVLL

rangeJoin :: (DV.Vector LBS.ByteString -> DV.Vector LBS.ByteString -> [LBS.ByteString])
  -> Int -> Int -> [DV.Vector LBS.ByteString] -> Int -> Int -> [DV.Vector LBS.ByteString] -> [[LBS.ByteString]]
rangeJoin f aa az as ba bz bs = rangeJoin' f (mapMaybe (mkEntry aa az) as) (mapMaybe (mkEntry ba bz) bs)

mkEntry :: Int -> Int -> DV.Vector LBS.ByteString -> Maybe (Word32, Word32, DV.Vector LBS.ByteString)
mkEntry a z v = (,, v) <$> lookupWord32 a v <*> lookupWord32 z v

lookupWord32 :: Int -> DV.Vector LBS.ByteString -> Maybe Word32
lookupWord32 i v = do
  lbs <- v DV.!? i
  let s = T.unpack (T.decodeUtf8 (LBS.toStrict lbs))
  readMaybe s

rangeJoin' :: (DV.Vector LBS.ByteString -> DV.Vector LBS.ByteString -> [LBS.ByteString])
  -> [(Word32, Word32, DV.Vector LBS.ByteString)] -> [(Word32, Word32, DV.Vector LBS.ByteString)] -> [[LBS.ByteString]]
rangeJoin' f ((ua, uz, u):us) ((va, vz, v):vs) = if
  | uz < va   -> ("L":encodeWord32 ua:encodeWord32  uz     :f u e):rangeJoin' f                  us  ((va    , vz, v):vs)
  | vz < ua   -> ("R":encodeWord32 va:encodeWord32  vz     :f e v):rangeJoin' f ((ua    , uz, u):us)                  vs
  | ua < va   -> ("L":encodeWord32 ua:encodeWord32 (va - 1):f u e):rangeJoin' f ((va    , uz, u):us) ((va    , vz, v):vs)
  | va < ua   -> ("R":encodeWord32 va:encodeWord32 (ua - 1):f e v):rangeJoin' f ((ua    , uz, u):us) ((ua    , vz, v):vs)
  | uz < vz   -> ("B":encodeWord32 ua:encodeWord32  uz     :f u v):rangeJoin' f                  us  ((uz + 1, vz, v):vs)
  | vz < uz   -> ("B":encodeWord32 va:encodeWord32  vz     :f u v):rangeJoin' f ((vz + 1, uz, u):us)                  vs
  | otherwise -> ("B":encodeWord32 va:encodeWord32  vz     :f u v):rangeJoin' f                  us                   vs
  where e = DV.empty
rangeJoin' f ((ua, uz, _):us) []                = ["L", encodeWord32 ua, encodeWord32 uz]:rangeJoin' f us []
rangeJoin' f []               ((va, vz, _):vs)  = ["R", encodeWord32 va, encodeWord32 vz]:rangeJoin' f [] vs
rangeJoin' _ []               []                = []

encodeWord32 :: Word32 -> LBS.ByteString
encodeWord32 = LBS.fromStrict . T.encodeUtf8 . T.pack . show

mkColumnSelector :: [Z.RangeJoinColumn] -> DV.Vector LBS.ByteString -> DV.Vector LBS.ByteString -> [LBS.ByteString]
mkColumnSelector []     _ _ = []
mkColumnSelector (c:cs) u v = case c of
  Z.LtColumn n -> fromMaybe "" (u DV.!? n):mkColumnSelector cs u v
  Z.RtColumn n -> fromMaybe "" (v DV.!? n):mkColumnSelector cs u v

runRangeJoin :: Z.RangeJoinOptions -> IO ()
runRangeJoin opts = do
  let input1Delimiter   = opts ^. the @"input1Delimiter"
  let input1FilePath    = opts ^. the @"input1FilePath"
  let input1StartColumn = opts ^. the @"input1StartColumn"
  let input1StopColumn  = opts ^. the @"input1StopColumn"
  let input2Delimiter   = opts ^. the @"input2Delimiter"
  let input2FilePath    = opts ^. the @"input2FilePath"
  let input2StartColumn = opts ^. the @"input2StartColumn"
  let input2StopColumn  = opts ^. the @"input2StopColumn"
  let columns           = opts ^. the @"columns"
  let outputFilePath    = opts ^. the @"outputFilePath"
  let outputDelimiter   = opts ^. the @"outputDelimiter"

  !rows1 <- SVLL.toListVector . SVL.makeCursor input1Delimiter <$> IO.readInputFile input1FilePath
  !rows2 <- SVLL.toListVector . SVL.makeCursor input2Delimiter <$> IO.readInputFile input2FilePath

  let !outDelimiterBuilder  = B.word8 outputDelimiter
  let !outNewlineBuilder    = B.word8 10
  let !columnSelector       = mkColumnSelector columns

  runResourceT $ do
    (_, hOut) <- IO.openOutputFile outputFilePath Nothing
    let outLbsss  = rangeJoin columnSelector input1StartColumn input1StopColumn rows1 input2StartColumn input2StopColumn rows2
    let outBss    = fmap (fmap B.lazyByteString) outLbsss
    let outB      = mconcat (L.intersperse outNewlineBuilder (fmap (mconcat . L.intersperse outDelimiterBuilder) outBss))
    liftIO $ B.hPutBuilder hOut outB
  return ()

cmdRangeJoin :: Mod CommandFields (IO ())
cmdRangeJoin = command "range-join" $ flip info idm $ runRangeJoin <$> optsRangeJoin

optsRangeJoin :: Parser Z.RangeJoinOptions
optsRangeJoin = Z.RangeJoinOptions
    <$> strOption
        (   long "input1"
        <>  help "Input DSV file 1"
        <>  metavar "FILE"
        )
    <*> option readWord8
        (   long "input1-delimiter"
        <>  help "DSV delimiter to use for input1"
        <>  metavar "CHAR"
        )
    <*> nonZeroOneBased
        (   long "input1-start-column"
        <>  short 'k'
        <>  help "Column to use as start column from 1"
        <>  metavar "COLUMN INDEX"
        )
    <*> nonZeroOneBased
        (   long "input1-stop-column"
        <>  short 'k'
        <>  help "Column to use as stop column from 1"
        <>  metavar "COLUMN INDEX"
        )
    <*> strOption
          (   long "input2"
          <>  help "Input DSV file 2"
          <>  metavar "FILE"
          )
    <*> option readWord8
        (   long "input2-delimiter"
        <>  help "DSV delimiter to use for input2"
        <>  metavar "CHAR"
        )
    <*> nonZeroOneBased
        (   long "input2-start-column"
        <>  short 'k'
        <>  help "Column to use as start column from 2"
        <>  metavar "COLUMN INDEX"
        )
    <*> nonZeroOneBased
        (   long "input2-stop-column"
        <>  short 'k'
        <>  help "Column to use as stop column from 2"
        <>  metavar "COLUMN INDEX"
        )
    <*> many
        ( rangeJoinColumn
          (   long "column"
          <>  short 'k'
          <>  help "Range join colum"
          <>  metavar "RANGE_JOIN_COLUMN"
          )
        )
    <*> strOption
        (   long "range-type"
        <>  short 'r'
        <>  help "Range type"
        <>  metavar "RANGE_TYPE"
        )
    <*> strOption
        (   long "output"
        <>  short 'o'
        <>  help "Output DSV file"
        <>  metavar "FILE"
        )
    <*> option readWord8
        (   long "output-delimiter"
        <>  short 'e'
        <>  help "DSV delimiter to write in the output"
        <>  metavar "CHAR"
        )