{-# LANGUAGE BlockArguments #-}
{-# LANGUAGE OverloadedRecordDot #-}

module Store
  ( commitDocument,
    replaceDocument,
  )
where

import Control.Exception (Exception, throwIO)
import Data.Aeson qualified as J
import Data.ByteString.Lazy qualified as LB
import Data.Default (Default (def))
import Data.List (intercalate)
import Data.String (IsString (fromString))
import Document qualified as D
import ProbabilityMap qualified as C
import System.Directory (copyFile)
import System.Exit (ExitCode (ExitFailure, ExitSuccess))
import System.IO.LockFile (withLockFile)
import System.Process.Typed (readProcessStderr)
import Text.Printf (printf)

replaceDocument :: String -> D.Document -> IO ()
replaceDocument message doc = do
  withGit do
    J.encodeFile doc.iFilePath doc.index
    oldDoc <- D.readDocument doc.iFileName
    _ <- C.modifyProbabilityCache (C.replaceDocument oldDoc doc)
    commitAll [doc.iFilePath, C.fileName] message

commitDocument :: String -> FilePath -> D.Document -> IO ()
commitDocument message original doc = do
  withGit do
    copyFile original doc.oFilePath
    J.encodeFile doc.iFilePath doc.index
    _ <- C.modifyProbabilityCache (C.addDocument doc)
    commitAll [doc.iFilePath, doc.oFilePath, C.fileName] message

withGit :: IO a -> IO a
withGit = withLockFile def ".gitlock"

commitAll :: [FilePath] -> String -> IO ()
commitAll fps m = do
  sh_ (">/dev/null git add -- " ++ intercalate " " (map (printf "'%s'") fps))
  sh_ (printf ">/dev/null git commit -m '%s' || :" m)

-- TODO Refacotor library `sh`
sh_ :: String -> IO ()
sh_ cmd = do
  -- printf "+ %s\n" cmd
  (exitCode, err) <- readProcessStderr (fromString cmd)
  case exitCode of
    ExitSuccess -> return ()
    ExitFailure exitCode' -> throwIO $ ProcessException exitCode' err

data ProcessException = ProcessException Int LB.ByteString
  deriving (Show)

instance Exception ProcessException