-----------------------------------------------------------------------------
-- |
-- Module      :  Database.DETS
-- Copyright   :  (c) 2020-2021 EMQ Technologies Co., Ltd.
-- License     :  BSD-style (see the LICENSE file)
--
-- Maintainer  :  Feng Lee, feng@emqx.io
--                Yang M, yangm@emqx.io
-- Stability   :  experimental
-- Portability :  portable
--
-- The Erlang DETS database.
--
-----------------------------------------------------------------------------
module Database.DETS where

import Control.Monad (IO)
import Data.Maybe (Maybe)
import Data.Pid (Pid)
import Data.Unit (Unit)
import Database.ETS as ETS
import System.IO (FilePath)

import Foreign (ffiIO0, ffiIO1, ffiIO2, ffiIO3)

type TableName = Atom

type TableInfo =
  { fileSize  :: Integer
  , fileName  :: FilePath
  , keyPos    :: Integer
  , size      :: Integer
  , tableType :: ETS.TableType
  }

data Option
  = AccessRead
  | AccessReadWrite
  | AutoSaveInfinity
  | AutoSave Integer
  | EstimatedNoObjects Integer
  | File FilePath
  | MaxNoSlots Integer
  | MinNoSlots Integer
  | Keypos Integer
  | RamFile Boolean
  | RepairForce
  | Repair Boolean
  | Bag
  | DuplicateBag
  | Set

all :: IO [TableName]
all = ffiIO0 :dets :all

close :: TableName -> IO ()
close = ffiIO1 :dets :close

foreign import delete :: forall k. TableName -> k -> IO ()

foreign import deleteAllObjects :: TableName -> IO ()

foreign import deleteObject :: TableName -> IO ()

foreign import first :: TableName -> forall k. IO (Maybe k)

foreign import next :: forall k. TableName -> k -> IO (Maybe k)

foreign import fromETS :: TableName -> ETS.TableId -> IO ()

foreign import info :: TableName -> IO (Maybe TableInfo)

foreign import insert :: forall v. TableName -> [v] -> IO ()

foreign import insertNew :: forall v. TableName -> [v] -> IO Boolean

foreign import lookup :: forall k v. TableName -> k -> IO [v]

foreign import toETS :: TableName -> ETS.TableId -> IO ()

foreign import foldl :: forall v acc. (v -> acc -> acc) -> acc -> TableName -> IO acc

foreign import foldr :: forall v acc. (v -> acc -> acc) -> acc -> TableName -> IO acc

foreign import infoWith :: TableName -> Atom -> IO (Maybe TableInfo)

isCompatibleBchunkFormat :: TableName -> Binary -> IO Boolean
isCompatibleBchunkFormat = ffiIO2 :dets :is_compatible_bchunk_format

foreign import isDetsFile :: FilePath -> IO Boolean

foreign import match :: forall a v. TableName -> a -> IO [v]

foreign import data Continuation :: Type

foreign import matchContinuation :: forall v. Continuation -> IO (Maybe ([v], Continuation))

foreign import matchWithLimit :: forall a v. TableName -> a -> Integer -> IO (Maybe ([v], Continuation))

foreign import matchDelete :: forall a. TableName -> a -> IO ()

foreign import matchObject :: forall a v. TableName -> a -> IO [v]

foreign import matchObjectContinuation :: forall v. Continuation -> IO (Maybe ([v], Continuation))

foreign import matchObjectWithLimit :: forall a v. TableName -> a -> Integer -> IO (Maybe ([v], Continuation))

foreign import openFile :: TableName -> [Option] -> IO TableName

foreign import pid2Name :: Pid -> IO (Maybe TableName)

safeFixtable :: TableName -> Boolean -> IO ()
safeFixtable = ffiIO2 :dets :safe_fixtable

foreign import slot :: forall v. TableName -> Integer -> IO (Maybe [v])

foreign import sync :: TableName -> IO ()

updateCounter :: forall k. TableName -> k -> Integer -> IO Integer
updateCounter = ffiIO3 :dets :update_counter

{- TODO
bchunk/2
init_table/2
init_table/3
open_file/1
repair_continuation/2
select/1
select/2
select/3
select_delete/2
table/1
table/2
traverse/2
-}