{-# LANGUAGE CApiFFI        #-}
{-# LANGUAGE EmptyDataDecls #-}
module Database.PostgreSQL.LibPQ.FFI where

import Data.Word        (Word8)
import Foreign.C.String (CString)
import Foreign.C.Types  (CChar, CInt (..), CSize (..), CUInt (..))
import Foreign.Ptr      (FunPtr, Ptr)

import Database.PostgreSQL.LibPQ.Internal (CNoticeBuffer, NoticeBuffer, PGconn)
import Database.PostgreSQL.LibPQ.Notify   (Notify, PGnotice)
import Database.PostgreSQL.LibPQ.Oid      (Oid (..))

-------------------------------------------------------------------------------
-- Types / Ptr tags
-------------------------------------------------------------------------------

data PGresult
data PGcancel

type CFd = CInt

type NoticeReceiver = NoticeBuffer -> Ptr PGresult -> IO ()

-------------------------------------------------------------------------------
-- FFI imports
-------------------------------------------------------------------------------

foreign import capi        "hs-libpq.h PQconnectdb"
    c_PQconnectdb :: CString -> IO (Ptr PGconn)

foreign import capi        "hs-libpq.h PQconnectStart"
    c_PQconnectStart :: CString -> IO (Ptr PGconn)

foreign import capi        "hs-libpq.h PQconnectPoll"
    c_PQconnectPoll :: Ptr PGconn -> IO CInt

foreign import capi unsafe "hs-libpq.h PQdb"
    c_PQdb :: Ptr PGconn -> IO CString

foreign import capi unsafe "hs-libpq.h PQuser"
    c_PQuser :: Ptr PGconn -> IO CString

foreign import capi unsafe "hs-libpq.h PQpass"
    c_PQpass :: Ptr PGconn -> IO CString

foreign import capi unsafe "hs-libpq.h PQhost"
    c_PQhost :: Ptr PGconn -> IO CString

foreign import capi unsafe "hs-libpq.h PQport"
    c_PQport :: Ptr PGconn -> IO CString

foreign import capi unsafe "hs-libpq.h PQoptions"
    c_PQoptions :: Ptr PGconn -> IO CString

foreign import capi unsafe "hs-libpq.h PQbackendPID"
    c_PQbackendPID :: Ptr PGconn -> IO CInt

foreign import capi unsafe "hs-libpq.h PQconnectionNeedsPassword"
    c_PQconnectionNeedsPassword :: Ptr PGconn -> IO CInt

foreign import capi unsafe "hs-libpq.h PQconnectionUsedPassword"
    c_PQconnectionUsedPassword :: Ptr PGconn -> IO CInt

foreign import capi unsafe "hs-libpq.h PQstatus"
    c_PQstatus :: Ptr PGconn -> IO CInt

foreign import capi unsafe "hs-libpq.h PQtransactionStatus"
    c_PQtransactionStatus :: Ptr PGconn -> IO CInt

-- TODO: GHC #22043
foreign import ccall       "hs-libpq.h PQparameterStatus"
    c_PQparameterStatus :: Ptr PGconn -> CString -> IO CString

foreign import capi unsafe "hs-libpq.h PQprotocolVersion"
    c_PQprotocolVersion :: Ptr PGconn -> IO CInt

foreign import capi unsafe "hs-libpq.h PQserverVersion"
    c_PQserverVersion :: Ptr PGconn -> IO CInt

foreign import capi unsafe "hs-libpq.h PQlibVersion"
    c_PQlibVersion :: IO CInt

foreign import capi unsafe "hs-libpq.h PQsocket"
    c_PQsocket :: Ptr PGconn -> IO CInt

foreign import capi        "hs-libpq.h PQerrorMessage"
    c_PQerrorMessage :: Ptr PGconn -> IO CString

foreign import capi        "hs-libpq.h PQfinish"
    c_PQfinish :: Ptr PGconn -> IO ()

foreign import capi        "hs-libpq.h PQreset"
    c_PQreset :: Ptr PGconn -> IO ()

foreign import capi        "hs-libpq.h PQresetStart"
    c_PQresetStart :: Ptr PGconn -> IO CInt

foreign import capi        "hs-libpq.h PQresetPoll"
    c_PQresetPoll :: Ptr PGconn -> IO CInt

foreign import capi unsafe "hs-libpq.h PQclientEncoding"
    c_PQclientEncoding :: Ptr PGconn -> IO CInt

-- TODO: GHC #22043
foreign import ccall        "hs-libpq.h pg_encoding_to_char"
    c_pg_encoding_to_char :: CInt -> IO CString

foreign import capi        "hs-libpq.h PQsetClientEncoding"
    c_PQsetClientEncoding :: Ptr PGconn -> CString -> IO CInt

type PGVerbosity = CInt
foreign import capi unsafe "hs-libpq.h PQsetErrorVerbosity"
    c_PQsetErrorVerbosity :: Ptr PGconn -> PGVerbosity -> IO PGVerbosity

foreign import capi        "hs-libpq.h PQputCopyData"
    c_PQputCopyData :: Ptr PGconn -> Ptr CChar -> CInt -> IO CInt

foreign import capi        "hs-libpq.h PQputCopyEnd"
    c_PQputCopyEnd :: Ptr PGconn -> CString -> IO CInt
 
-- TODO: GHC #22043
foreign import ccall       "hs-libpq.h PQgetCopyData"
    c_PQgetCopyData :: Ptr PGconn -> Ptr (Ptr Word8) -> CInt -> IO CInt

foreign import capi        "hs-libpq.h PQsendQuery"
    c_PQsendQuery :: Ptr PGconn -> CString -> IO CInt

-- TODO: GHC #22043
foreign import ccall       "hs-libpq.h PQsendQueryParams"
    c_PQsendQueryParams :: Ptr PGconn -> CString -> CInt -> Ptr Oid
                        -> Ptr CString -> Ptr CInt -> Ptr CInt -> CInt
                        -> IO CInt

foreign import capi        "hs-libpq.h PQsendPrepare"
    c_PQsendPrepare :: Ptr PGconn -> CString -> CString -> CInt -> Ptr Oid
                    -> IO CInt

-- TODO: GHC #22043
foreign import ccall       "hs-libpq.h PQsendQueryPrepared"
    c_PQsendQueryPrepared :: Ptr PGconn -> CString -> CInt -> Ptr CString
                          -> Ptr CInt -> Ptr CInt -> CInt -> IO CInt

foreign import capi        "hs-libpq.h PQsendDescribePrepared"
    c_PQsendDescribePrepared :: Ptr PGconn -> CString -> IO CInt

foreign import capi        "hs-libpq.h PQsendDescribePortal"
    c_PQsendDescribePortal :: Ptr PGconn -> CString -> IO CInt

foreign import capi        "hs-libpq.h PQflush"
    c_PQflush :: Ptr PGconn -> IO CInt

foreign import capi        "hs-libpq.h PQgetCancel"
    c_PQgetCancel :: Ptr PGconn -> IO (Ptr PGcancel)

foreign import capi        "hs-libpq.h &PQfreeCancel"
    p_PQfreeCancel :: FunPtr (Ptr PGcancel -> IO ())

foreign import capi        "hs-libpq.h PQcancel"
    c_PQcancel :: Ptr PGcancel -> CString -> CInt -> IO CInt

foreign import capi unsafe "hs-libpq.h PQnotifies"
    c_PQnotifies :: Ptr PGconn -> IO (Ptr Notify)

foreign import capi        "hs-libpq.h PQconsumeInput"
    c_PQconsumeInput :: Ptr PGconn -> IO CInt

foreign import capi unsafe "hs-libpq.h PQisBusy"
    c_PQisBusy :: Ptr PGconn -> IO CInt

foreign import capi        "hs-libpq.h PQsetnonblocking"
    c_PQsetnonblocking :: Ptr PGconn -> CInt -> IO CInt

foreign import capi unsafe "hs-libpq.h PQisnonblocking"
    c_PQisnonblocking :: Ptr PGconn -> IO CInt

foreign import capi unsafe "hs-libpq.h PQsetSingleRowMode"
    c_PQsetSingleRowMode :: Ptr PGconn -> IO CInt

foreign import capi        "hs-libpq.h PQgetResult"
    c_PQgetResult :: Ptr PGconn -> IO (Ptr PGresult)

foreign import capi        "hs-libpq.h PQexec"
    c_PQexec :: Ptr PGconn -> CString -> IO (Ptr PGresult)

-- TODO: GHC #22043
foreign import ccall       "hs-libpq.h PQexecParams"
    c_PQexecParams :: Ptr PGconn -> CString -> CInt -> Ptr Oid
                   -> Ptr CString -> Ptr CInt -> Ptr CInt -> CInt
                   -> IO (Ptr PGresult)

foreign import capi        "hs-libpq.h PQprepare"
    c_PQprepare :: Ptr PGconn -> CString -> CString -> CInt -> Ptr Oid
                -> IO (Ptr PGresult)

-- TODO: GHC #22043
foreign import ccall       "hs-libpq.h PQexecPrepared"
    c_PQexecPrepared :: Ptr PGconn -> CString -> CInt -> Ptr CString
                     -> Ptr CInt -> Ptr CInt -> CInt -> IO (Ptr PGresult)

foreign import capi        "hs-libpq.h PQdescribePrepared"
    c_PQdescribePrepared :: Ptr PGconn -> CString -> IO (Ptr PGresult)

foreign import capi        "hs-libpq.h PQdescribePortal"
    c_PQdescribePortal :: Ptr PGconn -> CString -> IO (Ptr PGresult)

foreign import capi        "hs-libpq.h &PQclear"
    p_PQclear :: FunPtr (Ptr PGresult -> IO ())

foreign import capi unsafe "hs-libpq.h PQresultStatus"
    c_PQresultStatus :: Ptr PGresult -> IO CInt

foreign import capi unsafe "hs-libpq.h PQresStatus"
    c_PQresStatus :: CInt -> IO CString

foreign import capi unsafe "hs-libpq.h PQresultErrorMessage"
    c_PQresultErrorMessage :: Ptr PGresult -> IO CString

foreign import capi        "hs-libpq.h PQresultErrorField"
    c_PQresultErrorField :: Ptr PGresult -> CInt -> IO CString

foreign import capi unsafe "hs-libpq.h PQntuples"
    c_PQntuples :: Ptr PGresult -> CInt

foreign import capi unsafe "hs-libpq.h PQnfields"
    c_PQnfields :: Ptr PGresult -> CInt

foreign import capi unsafe "hs-libpq.h PQfname"
    c_PQfname :: Ptr PGresult -> CInt -> IO CString

foreign import capi unsafe "hs-libpq.h PQfnumber"
    c_PQfnumber :: Ptr PGresult -> CString -> IO CInt

foreign import capi unsafe "hs-libpq.h PQftable"
    c_PQftable :: Ptr PGresult -> CInt -> IO Oid

foreign import capi unsafe "hs-libpq.h PQftablecol"
    c_PQftablecol :: Ptr PGresult -> CInt -> IO CInt

foreign import capi unsafe "hs-libpq.h PQfformat"
    c_PQfformat :: Ptr PGresult -> CInt -> IO CInt

foreign import capi unsafe "hs-libpq.h PQftype"
    c_PQftype :: Ptr PGresult -> CInt -> IO Oid

foreign import capi unsafe "hs-libpq.h PQfmod"
    c_PQfmod :: Ptr PGresult -> CInt -> IO CInt

foreign import capi unsafe "hs-libpq.h PQfsize"
    c_PQfsize :: Ptr PGresult -> CInt -> IO CInt

foreign import capi unsafe "hs-libpq.h PQgetvalue"
    c_PQgetvalue :: Ptr PGresult -> CInt -> CInt -> IO CString

foreign import capi unsafe "hs-libpq.h PQgetisnull"
    c_PQgetisnull :: Ptr PGresult -> CInt -> CInt -> IO CInt

foreign import capi unsafe "hs-libpq.h PQgetlength"
    c_PQgetlength :: Ptr PGresult -> CInt -> CInt -> IO CInt

foreign import capi unsafe "hs-libpq.h PQnparams"
    c_PQnparams :: Ptr PGresult -> IO CInt

foreign import capi unsafe "hs-libpq.h PQparamtype"
    c_PQparamtype :: Ptr PGresult -> CInt -> IO Oid

foreign import capi unsafe "hs-libpq.h PQcmdStatus"
    c_PQcmdStatus :: Ptr PGresult -> IO CString

foreign import capi unsafe "hs-libpq.h PQcmdTuples"
    c_PQcmdTuples :: Ptr PGresult -> IO CString

foreign import capi        "hs-libpq.h PQescapeStringConn"
    c_PQescapeStringConn :: Ptr PGconn
                         -> Ptr Word8 -- Actually (CString)
                         -> CString
                         -> CSize
                         -> Ptr CInt
                         -> IO CSize

foreign import capi        "hs-libpq.h PQescapeByteaConn"
    c_PQescapeByteaConn :: Ptr PGconn
                        -> CString -- Actually (Ptr CUChar)
                        -> CSize
                        -> Ptr CSize
                        -> IO (Ptr Word8) -- Actually (IO (Ptr CUChar))

foreign import capi        "hs-libpq.h PQunescapeBytea"
    c_PQunescapeBytea :: CString -- Actually (Ptr CUChar)
                      -> Ptr CSize
                      -> IO (Ptr Word8) -- Actually (IO (Ptr CUChar))

foreign import capi unsafe "hs-libpq.h PQescapeIdentifier"
    c_PQescapeIdentifier :: Ptr PGconn
                         -> CString
                         -> CSize
                         -> IO CString

foreign import capi unsafe "hs-libpq.h &PQfreemem"
    p_PQfreemem :: FunPtr (Ptr a -> IO ())

foreign import capi unsafe "hs-libpq.h PQfreemem"
    c_PQfreemem :: Ptr a -> IO ()

-------------------------------------------------------------------------------
-- FFI imports: noticebuffers
-------------------------------------------------------------------------------

foreign import capi unsafe "hs-libpq.h hs_postgresql_libpq_malloc_noticebuffer"
    c_malloc_noticebuffer :: IO (Ptr CNoticeBuffer)

foreign import capi unsafe "hs-libpq.h hs_postgresql_libpq_free_noticebuffer"
    c_free_noticebuffer :: Ptr CNoticeBuffer -> IO ()

foreign import capi unsafe "hs-libpq.h hs_postgresql_libpq_get_notice"
    c_get_notice :: Ptr CNoticeBuffer -> IO (Ptr PGnotice)

foreign import capi unsafe "hs-libpq.h &hs_postgresql_libpq_discard_notices"
    p_discard_notices :: FunPtr NoticeReceiver

foreign import capi unsafe "hs-libpq.h &hs_postgresql_libpq_store_notices"
    p_store_notices :: FunPtr NoticeReceiver

foreign import capi unsafe "hs-libpq.h PQsetNoticeReceiver"
    c_PQsetNoticeReceiver :: Ptr PGconn -> FunPtr NoticeReceiver -> Ptr CNoticeBuffer -> IO (FunPtr NoticeReceiver)

-------------------------------------------------------------------------------
-- FFI imports: Large Objects
-------------------------------------------------------------------------------

foreign import capi        "hs-libpq.h lo_creat"
    c_lo_creat :: Ptr PGconn -> CInt -> IO Oid

foreign import capi        "hs-libpq.h lo_create"
    c_lo_create :: Ptr PGconn -> Oid -> IO Oid

foreign import capi        "hs-libpq.h lo_import"
    c_lo_import :: Ptr PGconn -> CString -> IO Oid

foreign import capi        "hs-libpq.h lo_import_with_oid"
    c_lo_import_with_oid :: Ptr PGconn -> CString -> Oid -> IO Oid

foreign import capi        "hs-libpq.h lo_export"
    c_lo_export :: Ptr PGconn -> Oid -> CString -> IO CInt

foreign import capi        "hs-libpq.h lo_open"
    c_lo_open :: Ptr PGconn -> Oid -> CInt -> IO CFd

foreign import capi        "hs-libpq.h lo_write"
    c_lo_write :: Ptr PGconn -> CFd -> CString -> CSize -> IO CInt

foreign import capi        "hs-libpq.h lo_read"
    c_lo_read :: Ptr PGconn -> CFd -> Ptr Word8 -> CSize -> IO CInt

foreign import capi        "hs-libpq.h lo_lseek"
    c_lo_lseek :: Ptr PGconn -> CFd -> CInt -> CInt -> IO CInt

foreign import capi        "hs-libpq.h lo_tell"
    c_lo_tell :: Ptr PGconn -> CFd -> IO CInt

foreign import capi        "hs-libpq.h lo_truncate"
    c_lo_truncate :: Ptr PGconn -> CFd -> CSize -> IO CInt

foreign import capi        "hs-libpq.h lo_close"
    c_lo_close :: Ptr PGconn -> CFd -> IO CInt

foreign import capi        "hs-libpq.h lo_unlink"
    c_lo_unlink :: Ptr PGconn -> Oid -> IO CInt