{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE TemplateHaskell #-}

-- Copyright (C) 2011 John Millikin <jmillikin@gmail.com>
--
-- See license.txt for details
module Main
  ( tests
  , main
  ) where

import           Control.Monad.IO.Class (liftIO)
import qualified Data.ByteString
import           Data.ByteString.Char8 ()
import           Data.ByteString.Unsafe (unsafePackCStringLen)
import           Foreign (nullPtr)
import qualified GHC.IO.Exception as GHC
import           System.IO
import           Test.Chell

import           Data.Knob

main :: IO ()
main = Test.Chell.defaultMain tests

tests :: [Suite]
tests = [suite_File, suite_Duplex]

suite_File :: Suite
suite_File = suite "file" $ concatMap suiteTests
  [ suite "read"
    [ test_ReadFromStart
    , test_ReadFromOffset
    , test_ReadToEOF
    , test_ReadPastEOF
    ]
  , suite "write"
    [ test_WriteFromStart
    , test_WriteFromOffset
    , test_WritePastEOF
    , test_WriteAppended
    ]
  , suite "seek"
    [ test_SeekAbsolute
    , test_SeekRelative
    , test_SeekFromEnd
    , test_SeekBeyondMaxInt
    ]
  , suite "setSize"
    [ test_SetSize_Read
    , test_SetSize_Write
    , test_SetSize_ReadWrite
    , test_SetSize_Append
    ]
  ]
  ++ [ test_Ready
     , test_Close
     , test_SetContents
     , test_WithFileHandle
     ]

test_ReadFromStart :: Test
test_ReadFromStart = assertions "from-start" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" ReadMode

  bytes <- liftIO $ Data.ByteString.hGet h 3
  $expect (equal bytes "abc")

  off <- liftIO $ hTell h
  $expect (equal off 3)

test_ReadFromOffset :: Test
test_ReadFromOffset = assertions "from-offset" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" ReadMode

  liftIO $ hSeek h AbsoluteSeek 1
  bytes <- liftIO $ Data.ByteString.hGet h 3
  $expect (equal bytes "bcd")

  off <- liftIO $ hTell h
  $expect (equal off 4)

test_ReadToEOF :: Test
test_ReadToEOF = assertions "to-eof" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" ReadMode

  bytes <- liftIO $ Data.ByteString.hGet h 10
  $expect (equal bytes "abcde")

  off <- liftIO $ hTell h
  $expect (equal off 5)

test_ReadPastEOF :: Test
test_ReadPastEOF = assertions "past-eof" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" ReadMode

  liftIO $ hSeek h AbsoluteSeek 10
  bytes <- liftIO $ Data.ByteString.hGet h 10
  $expect (equal bytes "")

  off <- liftIO $ hTell h
  $expect (equal off 10)

test_WriteFromStart :: Test
test_WriteFromStart = assertions "from-start" $ do
  k <- newKnob ""
  h <- newFileHandle k "foo.txt" WriteMode
  liftIO $ hSetBuffering h NoBuffering

  liftIO $ Data.ByteString.hPut h "abcde"
  bytes <- Data.Knob.getContents k
  $expect (equal bytes "abcde")

test_WriteFromOffset :: Test
test_WriteFromOffset = assertions "from-offset" $ do
  k <- newKnob ""
  h <- newFileHandle k "foo.txt" WriteMode
  liftIO $ hSetBuffering h NoBuffering

  liftIO $ Data.ByteString.hPut h "abcde"
  liftIO $ hSeek h AbsoluteSeek 2
  liftIO $ Data.ByteString.hPut h "abcde"

  bytes <- Data.Knob.getContents k
  $expect (equal bytes "ababcde")

test_WritePastEOF :: Test
test_WritePastEOF = assertions "past-eof" $ do
  k <- newKnob ""
  h <- newFileHandle k "foo.txt" WriteMode
  liftIO $ hSetBuffering h NoBuffering

  liftIO $ hSeek h AbsoluteSeek 2
  liftIO $ Data.ByteString.hPut h "abcde"
  bytes <- Data.Knob.getContents k
  $expect (equal bytes "\0\0abcde")

test_WriteAppended :: Test
test_WriteAppended = assertions "appended" $ do
  k <- newKnob "foo"
  h <- newFileHandle k "foo.txt" AppendMode
  liftIO $ hSetBuffering h NoBuffering

  liftIO $ Data.ByteString.hPut h "bar"
  bytes <- Data.Knob.getContents k
  $expect (equal bytes "foobar")

test_SeekAbsolute :: Test
test_SeekAbsolute = assertions "absolute" $ do
  k <- newKnob ""
  h <- newFileHandle k "foo.txt" ReadMode

  before <- liftIO $ hTell h
  liftIO $ hSeek h AbsoluteSeek 2
  after <- liftIO $ hTell h

  $expect (equal before 0)
  $expect (equal after 2)

test_SeekRelative :: Test
test_SeekRelative = assertions "relative" $ do
  k <- newKnob ""
  h <- newFileHandle k "foo.txt" ReadMode

  before <- liftIO $ hTell h
  liftIO $ hSeek h RelativeSeek 2
  after1 <- liftIO $ hTell h
  liftIO $ hSeek h RelativeSeek 2
  after2 <- liftIO $ hTell h

  $expect (equal before 0)
  $expect (equal after1 2)
  $expect (equal after2 4)

test_SeekFromEnd :: Test
test_SeekFromEnd = assertions "from-end" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" ReadMode

  before <- liftIO $ hTell h
  liftIO $ hSeek h SeekFromEnd (- 2)
  after <- liftIO $ hTell h

  $expect (equal before 0)
  $expect (equal after 3)

test_SeekBeyondMaxInt :: Test
test_SeekBeyondMaxInt = assertions "beyond-max-int" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" ReadMode

  let intPlusOne = toInteger (maxBound :: Int) + 1

  $expect $ throwsEq
    (GHC.IOError (Just h) GHC.InvalidArgument "hSeek" "offset > (maxBound :: Int)" Nothing (Just "foo.txt"))
    (hSeek h AbsoluteSeek intPlusOne)
  $expect $ throwsEq
    (GHC.IOError (Just h) GHC.InvalidArgument "hSeek" "offset > (maxBound :: Int)" Nothing (Just "foo.txt"))
    (hSeek h RelativeSeek intPlusOne)

  -- testing this with real contents is difficult/impossible on a
  -- 64-bit system, so use an unsafe function to corrupt the knob's
  -- internal buffer first.
  hugeBytes <- liftIO (unsafePackCStringLen (nullPtr, maxBound))
  liftIO $ hSeek h AbsoluteSeek (intPlusOne - 1)
  setContents k hugeBytes
  $expect $ throwsEq
    (GHC.IOError (Just h) GHC.InvalidArgument "hSeek" "offset > (maxBound :: Int)" Nothing (Just "foo.txt"))
    (hSeek h SeekFromEnd 2)

test_Ready :: Test
test_Ready = assertions "ready" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" ReadMode

  ready <- liftIO $ hReady h
  $expect ready

  _ <- liftIO $ Data.ByteString.hGet h 10
  $expect $ throwsEq
    (GHC.IOError (Just h) GHC.EOF "hWaitForInput" "" Nothing (Just "foo.txt"))
    (hReady h)

test_Close :: Test
test_Close = assertions "close" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" ReadMode

  liftIO $ hClose h
  $expect $ throwsEq
    (GHC.IOError (Just h) GHC.IllegalOperation "hGetBuf" "handle is closed" Nothing (Just "foo.txt"))
    (Data.ByteString.hGet h 1)
  $expect $ throwsEq
    (GHC.IOError (Just h) GHC.IllegalOperation "hWaitForInput" "handle is closed" Nothing (Just "foo.txt"))
    (hReady h)

test_SetSize_Read :: Test
test_SetSize_Read = assertions "ReadMode" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" ReadMode

  let intPlusOne = toInteger (maxBound :: Int) + 1
  $expect $ throwsEq
    (GHC.IOError (Just h) GHC.InvalidArgument "hSetFileSize" "size > (maxBound :: Int)" Nothing (Just "foo.txt"))
    (hSetFileSize h intPlusOne)

  $expect $ throwsEq
    (GHC.IOError (Just h) GHC.IllegalOperation "hSetFileSize" "handle in ReadMode" Nothing (Just "foo.txt"))
    (hSetFileSize h 2)

test_SetSize_Write :: Test
test_SetSize_Write = assertions "WriteMode" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" WriteMode

  let intPlusOne = toInteger (maxBound :: Int) + 1
  $expect $ throwsEq
    (GHC.IOError (Just h) GHC.InvalidArgument "hSetFileSize" "size > (maxBound :: Int)" Nothing (Just "foo.txt"))
    (hSetFileSize h intPlusOne)

  -- Resets contents to all NULL, regardless of offset
  liftIO $ hSeek h AbsoluteSeek 2
  liftIO $ hSetFileSize h 4

  bytes <- Data.Knob.getContents k
  $expect (equal bytes "\0\0\0\0")

test_SetSize_ReadWrite :: Test
test_SetSize_ReadWrite = assertions "ReadWriteMode" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" ReadWriteMode

  let intPlusOne = toInteger (maxBound :: Int) + 1
  $expect $ throwsEq
    (GHC.IOError (Just h) GHC.InvalidArgument "hSetFileSize" "size > (maxBound :: Int)" Nothing (Just "foo.txt"))
    (hSetFileSize h intPlusOne)

  -- Truncates contents, regardless of offset
  do
    liftIO $ hSeek h AbsoluteSeek 2
    liftIO $ hSetFileSize h 4
    bytes <- Data.Knob.getContents k
    $expect (equal bytes "abcd")

  do
    liftIO $ hSetFileSize h 6
    bytes <- Data.Knob.getContents k
    $expect (equal bytes "abcd\0\0")

test_SetSize_Append :: Test
test_SetSize_Append = assertions "AppendMode" $ do
  k <- newKnob "abcde"
  h <- newFileHandle k "foo.txt" AppendMode

  let intPlusOne = toInteger (maxBound :: Int) + 1
  $expect $ throwsEq
    (GHC.IOError (Just h) GHC.InvalidArgument "hSetFileSize" "size > (maxBound :: Int)" Nothing (Just "foo.txt"))
    (hSetFileSize h intPlusOne)

  do
    liftIO $ hSetFileSize h 4
    bytes <- Data.Knob.getContents k
    $expect (equal bytes "abcd")

  do
    liftIO $ hSetFileSize h 6
    bytes <- Data.Knob.getContents k
    $expect (equal bytes "abcd\0\0")

test_SetContents :: Test
test_SetContents = assertions "setContents" $ do
  k <- newKnob "abcde"
  before <- Data.Knob.getContents k
  setContents k "foo"
  after <- Data.Knob.getContents k

  $expect (equal before "abcde")
  $expect (equal after "foo")

test_WithFileHandle :: Test
test_WithFileHandle = assertions "withFileHandle" $ do
  k <- newKnob ""
  h <- withFileHandle k "test.txt" WriteMode $ \h -> do
    Data.ByteString.hPut h "abcde"
    return h

  bytes <- Data.Knob.getContents k
  $expect (equal bytes "abcde")

  closed <- liftIO $ hIsClosed h
  $expect closed

suite_Duplex :: Suite
suite_Duplex = suite "duplex" []