{-# OPTIONS_GHC -Wall #-}

module Main where

import Test.Framework (defaultMain, testGroup, Test )
import Test.Framework.Providers.HUnit
import Test.HUnit ( assertBool )

import System.IO ( openTempFile, stderr )
import System.Process ( runProcess, waitForProcess )
import System.FilePath ( (</>), (<.>) )
import System.Directory
import System.Exit
import Data.Algorithm.Diff
import Text.Pandoc.Shared ( substitute, normalize, defaultWriterOptions )
import Text.Pandoc.Writers.Native ( writeNative )
import Text.Pandoc.Highlighting ( languages )
import Prelude hiding ( readFile )
import qualified Data.ByteString.Lazy as B
import Data.ByteString.Lazy.UTF8 (toString)

readFileUTF8 :: FilePath -> IO String
readFileUTF8 f = B.readFile f >>= return . toString

pandocPath :: FilePath
pandocPath = ".." </> "dist" </> "build" </> "pandoc" </> "pandoc"

data TestResult = TestPassed
                | TestError ExitCode
                | TestFailed String FilePath [(DI, String)]
     deriving (Eq)

instance Show TestResult where
  show TestPassed     = "PASSED"
  show (TestError ec) = "ERROR " ++ show ec
  show (TestFailed cmd file d) = cmd ++ "\n--- expected (" ++ file ++ ")" ++
                                 "\n+++ actual\n" ++ showDiff d

showDiff :: [(DI, String)] -> String
showDiff []             = ""
showDiff ((F, ln) : ds) = "+ " ++ ln ++ "\n" ++ showDiff ds
showDiff ((S, ln) : ds) = "- " ++ ln ++ "\n" ++ showDiff ds
showDiff ((B, _ ) : ds) = showDiff ds

tests :: [Test]
tests = [ testGroup "markdown" [ testGroup "writer" (writerTests "markdown" ++ lhsWriterTests "markdown")
                               , testGroup "reader" [ test "basic" ["-r", "markdown", "-w", "native", "-s", "-S"]
                                                      "testsuite.txt" "testsuite.native"
                                                    , test "tables" ["-r", "markdown", "-w", "native", "--columns=80"]
                                                      "tables.txt" "tables.native"
                                                    , test "more" ["-r", "markdown", "-w", "native", "-S"]
                                                      "markdown-reader-more.txt" "markdown-reader-more.native"
                                                    , lhsReaderTest "markdown+lhs"
                                                    ]
                               , testGroup "citations" markdownCitationTests
                               ]
        , testGroup "rst"      [ testGroup "writer" (writerTests "rst" ++ lhsWriterTests "rst")
                               , testGroup "reader" [ test "basic" ["-r", "rst", "-w", "native", "-s", "-S", "--columns=80"]
                                                      "rst-reader.rst" "rst-reader.native"
                                                    , test "tables" ["-r", "rst", "-w", "native", "--columns=80"]
                                                      "tables.rst" "tables-rstsubset.native"
                                                    , lhsReaderTest "rst+lhs"
                                                    ]
                               ]
        , testGroup "latex"    [ testGroup "writer" (writerTests "latex" ++ lhsWriterTests "latex")
                               , testGroup "reader" [ test "basic" ["-r", "latex", "-w", "native", "-s", "-R"]
                                                      "latex-reader.latex" "latex-reader.native"
                                                    , lhsReaderTest "latex+lhs"
                                                    ]
                               , latexCitationTests "biblatex"
                               , latexCitationTests "natbib"
                               ]
        , testGroup "html"     [ testGroup "writer" (writerTests "html" ++ lhsWriterTests "html")
                               , test "reader" ["-r", "html", "-w", "native", "-s"]
                                 "html-reader.html" "html-reader.native"
                               ]
        , testGroup "s5"       [ s5WriterTest "basic" ["-s"] "s5"
                               , s5WriterTest "fancy" ["-s","-m","-i"] "s5"
                               , s5WriterTest "fragment" [] "html"
                               , s5WriterTest "inserts"  ["-s", "-H", "insert",
                                                             "-B", "insert", "-A", "insert", "-c", "main.css"] "html"
                               ]
        , testGroup "textile"  [ testGroup "writer" $ writerTests "textile"
                               , test "reader" ["-r", "textile", "-w", "native", "-s"]
                                 "textile-reader.textile" "textile-reader.native"
                               ]
        , testGroup "native"   [ testGroup "writer" $ writerTests "native"
                               , test "reader" ["-r", "native", "-w", "native", "-s"]
                                 "testsuite.native" "testsuite.native"
                               ]
        , testGroup "other writers" $ map (\f -> testGroup f $ writerTests f)
          [ "docbook", "opendocument" , "context" , "texinfo"
          , "man" , "plain" , "mediawiki", "rtf", "org"
          ]
        ]

main :: IO ()
main = defaultMain tests

-- makes sure file is fully closed after reading
readFile' :: FilePath -> IO String
readFile' f = do s <- readFileUTF8 f
                 return $! (length s `seq` s)

lhsWriterTests :: String -> [Test]
lhsWriterTests format
  = [ t "lhs to normal" format
    , t "lhs to lhs"    (format ++ "+lhs")
    ]
  where
    t n f = test n ["--columns=78", "-r", "native", "-s", "-w", f] "lhs-test.native" ("lhs-test" <.> ext f)
    ext f = if null languages && format == "html"
               then "nohl" <.> f
               else f

lhsReaderTest :: String -> Test
lhsReaderTest format =
  testWithNormalize normalizer "lhs" ["-r", format, "-w", "native"] ("lhs-test" <.> format) "lhs-test.native"
   where normalizer = writeNative defaultWriterOptions . normalize . read

latexCitationTests :: String -> Test
latexCitationTests n
  = testGroup (n ++ " citations")
    [ t ("latex reader (" ++ n ++ " citations)") (["-r", "latex", "-w", "markdown", "-s", "--no-wrap"] ++ o)
      f "markdown-citations.txt"
    , t ("latex writer (" ++ n ++ " citations)") (["-r", "markdown", "-w", "latex", "-s", "--no-wrap"] ++ o)
      "markdown-citations.txt" f
    ]
  where
    o = ["--bibliography", "biblio.bib", "--csl", "chicago-author-date.csl", "--no-citeproc", "--" ++ n]
    f  = n ++ "-citations.latex"
    normalizer = substitute "\160" " " . substitute "\8211" "-"
    t          = testWithNormalize normalizer

writerTests :: String -> [Test]
writerTests format
  = [ test "basic"  (opts ++ ["-s"]) "testsuite.native" ("writer" <.> format)
    , test "tables" opts             "tables.native"    ("tables" <.> format)
    ]
  where
    opts = ["-r", "native", "-w", format, "--columns=78"]

s5WriterTest :: String -> [String] -> String -> Test
s5WriterTest modifier opts format 
  = test (format ++ " writer (" ++ modifier ++ ")") (["-r", "native", "-w", format] ++ opts) 
    "s5.native"  ("s5." ++ modifier <.> "html")

markdownCitationTests :: [Test]
markdownCitationTests
  =  map styleToTest ["chicago-author-date","ieee","mhra"] 
     ++ [test "no-citeproc" wopts "markdown-citations.txt" "markdown-citations.txt"]
  where
    ropts             = ["-r", "markdown", "-w", "markdown", "--bibliography", "biblio.bib", "--no-wrap"]
    wopts             = ropts ++ ["--no-citeproc"]
    styleToTest style = test style (ropts ++ ["--csl", style ++ ".csl"])
                        "markdown-citations.txt" ("markdown-citations." ++ style ++ ".txt")

-- | Run a test without normalize function, return True if test passed.
test :: String    -- ^ Title of test
     -> [String]  -- ^ Options to pass to pandoc
     -> String    -- ^ Input filepath
     -> FilePath  -- ^ Norm (for test results) filepath
     -> Test
test = testWithNormalize id

-- | Run a test with normalize function, return True if test passed.
testWithNormalize  :: (String -> String) -- ^ Normalize function for output
                   -> String    -- ^ Title of test
                   -> [String]  -- ^ Options to pass to pandoc
                   -> String    -- ^ Input filepath
                   -> FilePath  -- ^ Norm (for test results) filepath
                   -> Test
testWithNormalize normalizer testname opts inp norm = testCase testname $ do
  (outputPath, hOut) <- openTempFile "" "pandoc-test"
  let inpPath = inp
  let normPath = norm
  let options = ["--data-dir", ".."] ++ [inpPath] ++ opts
  let cmd = pandocPath ++ " " ++ unwords options
  ph <- runProcess pandocPath options Nothing
        (Just [("LANG","en_US.UTF-8"),("HOME", "./")]) Nothing (Just hOut) (Just stderr)
  ec <- waitForProcess ph
  result  <- if ec == ExitSuccess
                then do
                  -- filter \r so the tests will work on Windows machines
                  outputContents <- readFile' outputPath >>= return . filter (/='\r') . normalizer
                  normContents <- readFile' normPath >>= return . filter (/='\r') . normalizer
                  if outputContents == normContents
                     then return TestPassed
                     else return $ TestFailed cmd normPath $ getDiff (lines outputContents) (lines normContents)
                else return $ TestError ec
  removeFile outputPath
  assertBool (show result) (result == TestPassed)