{-# LANGUAGE BangPatterns        #-}
{-# LANGUAGE DataKinds           #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeApplications    #-}

module App.Commands.CreateIndex
  ( cmdCreateIndex
  ) where

import Control.Lens
import Control.Monad
import Data.Generics.Product.Any
import Data.Maybe
import Data.Semigroup            ((<>))
import Data.Word
import Foreign
import Options.Applicative       hiding (columns)

import qualified App.Commands.Types                                                  as Z
import qualified Data.ByteString                                                     as BS
import qualified Data.ByteString.Internal                                            as BSI
import qualified Data.ByteString.Lazy                                                as LBS
import qualified HaskellWorks.Data.ByteString                                        as BS
import qualified HaskellWorks.Data.ByteString.Lazy                                   as LBS
import qualified HaskellWorks.Data.Json.Backend.Simple.SemiIndex                     as SISI
import qualified HaskellWorks.Data.Json.Backend.Standard.SemiIndex                   as STSI
import qualified HaskellWorks.Data.Json.Internal.Backend.Standard.Blank              as J
import qualified HaskellWorks.Data.Json.Internal.Backend.Standard.BlankedJson        as J
import qualified HaskellWorks.Data.Json.Internal.Backend.Standard.MakeIndex          as J
import qualified HaskellWorks.Data.Json.Internal.Backend.Standard.ToBalancedParens64 as J
import qualified HaskellWorks.Data.Json.Simd.Index.Standard                          as STSI
import qualified System.Exit                                                         as IO
import qualified System.IO                                                           as IO
import qualified System.IO.MMap                                                      as IO

{-# ANN module ("HLint: ignore Reduce duplication"  :: String) #-}
{-# ANN module ("HLint: ignore Redundant do"        :: String) #-}

runCreateIndexStandard :: Z.CreateIndexOptions -> IO ()
runCreateIndexStandard opts = do
  let filePath = opts ^. the @"filePath"
  let outputIbFile = opts ^. the @"outputIbFile" & fromMaybe (filePath <> ".ib.idx")
  let outputBpFile = opts ^. the @"outputBpFile" & fromMaybe (filePath <> ".bp.idx")
  case opts ^. the @"method" of
    "original" -> do
      (fptr :: ForeignPtr Word8, offset, size) <- IO.mmapFileForeignPtr filePath IO.ReadOnly Nothing
      let !bs = BSI.fromForeignPtr (castForeignPtr fptr) offset size
      let blankedJson = J.blankJson [bs]
      let ibs = LBS.fromChunks (J.blankedJsonToInterestBits blankedJson)
      let bps = J.toBalancedParens64 (J.BlankedJson blankedJson)
      LBS.writeFile outputIbFile ibs
      LBS.writeFile outputBpFile (LBS.toLazyByteString bps)
    "alternate" -> do
      (fptr :: ForeignPtr Word8, offset, size) <- IO.mmapFileForeignPtr filePath IO.ReadOnly Nothing
      let !bs = BSI.fromForeignPtr (castForeignPtr fptr) offset size
      let STSI.SemiIndex ib bp = STSI.buildSemiIndex bs
      BS.writeFile outputIbFile (BS.toByteString ib)
      BS.writeFile outputBpFile (BS.toByteString bp)
    "tabular" -> do
      lbs <- LBS.readFile filePath
      let siChunks = STSI.toIbBpBuilders (STSI.buildFromByteString3 (BS.resegmentPadded 64 (LBS.toChunks lbs)))
      IO.withFile outputIbFile IO.WriteMode $ \hIb ->
        IO.withFile outputBpFile IO.WriteMode $ \hBp ->
          forM_ siChunks $ \(STSI.SiChunk ib bp) -> do
            LBS.hPut hIb (LBS.toLazyByteString ib)
            LBS.hPut hBp (LBS.toLazyByteString bp)
    "simd" -> do
      IO.withFile filePath IO.ReadMode $ \hIn -> do
        contents <- LBS.resegmentPadded 512 <$> LBS.hGetContents hIn
        case STSI.makeStandardJsonIbBps contents of
          Right chunks -> do
            IO.withFile outputIbFile IO.WriteMode $ \hIb -> do
              IO.withFile outputBpFile IO.WriteMode $ \hBp -> do
                forM_ chunks $ \(ibBs, bpBs) -> do
                  BS.hPut hIb ibBs
                  BS.hPut hBp bpBs
          Left msg -> IO.hPutStrLn IO.stderr $ "Unable to create index: " <> show msg
    "sum" -> do
      lbs <- LBS.resegmentPadded 64 <$> LBS.readFile filePath
      IO.putStrLn $ "Sum: " <> show (sum (BS.foldl (\a b -> a + fromIntegral b) (0 :: Word64) <$> LBS.toChunks lbs))
    unknown -> do
      IO.hPutStrLn IO.stderr $ "Unknown method " <> show unknown
      IO.exitFailure

runCreateIndexSimple :: Z.CreateIndexOptions -> IO ()
runCreateIndexSimple opts = do
  let filePath = opts ^. the @"filePath"
  let outputIbFile = opts ^. the @"outputIbFile" & fromMaybe (filePath <> ".ib.idx")
  let outputBpFile = opts ^. the @"outputBpFile" & fromMaybe (filePath <> ".bp.idx")
  (fptr :: ForeignPtr Word8, offset, size) <- IO.mmapFileForeignPtr filePath IO.ReadOnly Nothing
  let !bs = BSI.fromForeignPtr (castForeignPtr fptr) offset size
  let SISI.SemiIndex _ ibs bps = SISI.buildSemiIndex bs
  LBS.writeFile outputIbFile (LBS.toLazyByteString ibs)
  LBS.writeFile outputBpFile (LBS.toLazyByteString bps)

runCreateIndex :: Z.CreateIndexOptions -> IO ()
runCreateIndex opts = case opts ^. the @"backend" of
  "standard" -> runCreateIndexStandard  opts
  "simple"   -> runCreateIndexSimple    opts
  unknown    -> IO.hPutStrLn IO.stderr $ "Unknown backend " <> show unknown

optsCreateIndex :: Parser Z.CreateIndexOptions
optsCreateIndex = Z.CreateIndexOptions
  <$> strOption
        (   long "input"
        <>  short 'i'
        <>  help "Input JSON file"
        <>  metavar "STRING"
        )
  <*> strOption
        (   long "backend"
        <>  short 'b'
        <>  value "standard"
        <>  help "Backend for creating index"
        <>  metavar "STRING"
        )
  <*> strOption
        (   long "method"
        <>  short 'm'
        <>  value "original"
        <>  help "Method for creating index"
        <>  metavar "STRING"
        )
  <*> optional
        ( strOption
          (   long "output-ib-file"
          <>  help "Filename for output ib index"
          <>  metavar "STRING"
          )
        )
  <*> optional
        ( strOption
          (   long "output-bp-file"
          <>  help "Filename for output bp index"
          <>  metavar "STRING"
          )
        )

cmdCreateIndex :: Mod CommandFields (IO ())
cmdCreateIndex = command "create-index"  $ flip info idm $ runCreateIndex <$> optsCreateIndex