{-# LANGUAGE CPP #-}

-- |
-- Module      :  PackageUtils
-- Copyright   :  (C) 2013-2020  Jens Petersen
--
-- Maintainer  :  Jens Petersen <petersen@fedoraproject.org>
-- Stability   :  alpha
-- Portability :  portable
--
-- Explanation: functions related to Cabal dependency generation.

-- This program is free software: you can redistribute it and/or modify
-- it under the terms of the GNU General Public License as published by
-- the Free Software Foundation, either version 3 of the License, or
-- (at your option) any later version.

module PackageUtils (
  bringTarball,
  cabal_,
  checkForSpecFile,
  dropChangelog,
  editSpecField,
  getRevisedCabal,
  getSpecField,
  latestPackage,
  PackageData (..),
  packageManager,
  patchSpec,
  pkgSpecPkgData,
  prepare,
  repoquery,
  rpmbuild,
  rpmInstall,
  RpmStage (..)
  ) where

import FileUtils (assertFileNonEmpty, filesWithExtension, fileWithExtension,
                  getDirectoryContents_, mktempdir, withCurrentDirectory,
                  withTempDirectory)
import SimpleCabal (finalPackageDescription, licenseFiles, mkPackageName,
                    PackageDescription, PackageIdentifier(..), PackageName,
                    tryFindPackageDesc)
import SimpleCmd (cmd, cmd_, cmdBool, cmdIgnoreErr, cmdLines,
#if MIN_VERSION_simple_cmd(0,2,2)
                  cmdStderrToStdout,
#else
                  cmdSilent,
#endif
                  error', grep_, removePrefix, sudo, sudo_, (+-+))
import SimpleCmd.Git (isGitDir, grepGitConfig)
import SimpleCmd.Rpm (rpmspec)
import SysCmd (optionalProgram, requireProgram, rpmEval)
#if MIN_VERSION_simple_cmd(0,2,2)
import System.Exit (ExitCode (..))
#endif
import Stackage (defaultLTS, latestStackage)
import Types

#if (defined(MIN_VERSION_base) && MIN_VERSION_base(4,8,0))
#else
import Control.Applicative ((<$>))
#endif
import Control.Monad    (filterM, unless, void, when)

import Data.Char (toLower)
import Data.List
import Data.Maybe
import Data.Time.Clock (diffUTCTime, getCurrentTime)

import Distribution.Text (display, simpleParse)

import System.Directory (copyFile, createDirectoryIfMissing, doesDirectoryExist,
                         doesFileExist, getCurrentDirectory,
                         getDirectoryContents, getModificationTime,
                         removeDirectoryRecursive, renameFile,
                         setCurrentDirectory)
import System.Environment (getEnv)
import System.FilePath
import System.IO (hIsTerminalDevice, stdout)
import System.Posix.Files (accessTime, fileMode, getFileStatus,
                           modificationTime, setFileMode)

simplePackageDescription :: Flags -> FilePath
                         -> IO (PackageDescription, [FilePath], [FilePath])
simplePackageDescription flags cabalfile = do
  final <- finalPackageDescription flags cabalfile
  (docs, licensefiles) <- findDocsLicenses (dropFileName cabalfile) final
  return (final, docs, licensefiles)

findDocsLicenses :: FilePath -> PackageDescription -> IO ([FilePath], [FilePath])
findDocsLicenses dir pkgDesc = do
  contents <- getDirectoryContents dir
  let docs = sort $ filter unlikely $ filter (likely docNames) contents
  let licenses = sort $ nub $ licenseFiles pkgDesc
        ++ filter (likely licenseNames) contents
      docfiles = if null licenses then docs else filter (`notElem` licenses) docs
  return (docfiles, licenses)
  where docNames = ["announce", "author", "bugs", "changelog", "changes",
                    "contribut", "example", "news", "readme", "todo"]
        licenseNames = ["copying", "licence", "license"]
        likely names name = let lowerName = map toLower name
                      in any (`isPrefixOf` lowerName) names
        unlikely name = not $ any (`isSuffixOf` name) ["~", ".cabal"]

bringTarball :: PackageIdentifier -> Bool -> Maybe FilePath -> IO ()
bringTarball pkgid revise mspec = do
  let tarfile = display pkgid <.> "tar.gz"
  havespec <- case mspec of
                Nothing -> return False
                Just spec -> doesFileExist spec
  sources <- if havespec
             then map sourceFieldFile <$> cmdLines "spectool" ["-S", fromJust mspec]
             else return [tarfile]
  srcdir <- getSourceDir
  allExist <- and <$> mapM (doesFileExist . (srcdir </>)) sources
  unless allExist $ do
    pkggit <- grepGitConfig "\\(pkgs\\|src\\)."
    when pkggit $ do
      srcnv <- grep_ tarfile "sources"
      when srcnv $
        cmd_ "fedpkg" ["sources"]
    when havespec $
      createDirectoryIfMissing True srcdir
    mapM_ (copyTarball False srcdir) sources
    haveLocalCabal <- doesFileExist $ srcdir </> display pkgid <.> "cabal"
    when (not haveLocalCabal && revise) $
      void $ getRevisedCabal pkgid
    allExist' <- and <$> mapM (doesFileExist . (srcdir </>)) sources
    when (not allExist' && havespec) $
      cmd_ "spectool" ["-g", "-S", "-C", srcdir, fromJust mspec]
 where
  sourceFieldFile :: String -> FilePath
  sourceFieldFile field =
    if null field then
      -- should be impossible
      error "empty source field!"
    else (takeFileName . last . words) field

  copyTarball :: Bool -> FilePath -> FilePath -> IO ()
  copyTarball ranFetch dir file =
   when (takeExtensions file == ".tar.gz") $ do
    let dest = dir </> file
    already <- doesFileExist dest
    unless already $ do
      home <- getEnv "HOME"
      let cacheparent = home </> ".cabal" </> "packages"
      havecache <- doesDirectoryExist cacheparent
      unless havecache cabalUpdate
      remotes <- getDirectoryContents_ cacheparent

      let pkgid' =
            fromMaybe (error' $ "Parse failed for:" +-+ dropExtensions file) $
            simpleParse (dropExtensions file)
          tarfile = display pkgid' <.> "tar.gz"
          tarpath =
              display (pkgName pkgid') </> display (pkgVersion pkgid') </> tarfile
          paths = map (\ repo -> cacheparent </> repo </> tarpath) remotes
      -- if more than one tarball, should maybe warn if they are different
      tarballs <- filterM doesFileExist paths
      if null tarballs
        then if ranFetch
             then error $ "no" +-+ tarfile +-+ "found"
             else do
             cabal_ "fetch" ["-v0", "--no-dependencies", display pkgid']
             copyTarball True dir file
        else do
        createDirectoryIfMissing True dir
        copyFile (head tarballs) dest
        -- cabal-1.18 fetch creates tarballs with mode 0600
        stat <- getFileStatus dest
        when (fileMode stat /= 0o100644) $
          setFileMode dest 0o0644

getSourceDir :: IO FilePath
getSourceDir = do
    git <- isGitDir "."
    if git
      then getCurrentDirectory
      else fromJust <$> rpmEval "%{_sourcedir}"

getRevisedCabal :: PackageIdentifier -> IO Bool
getRevisedCabal pkgid = do
  let file = display (pkgName pkgid) <.> "cabal"
  dir <- getSourceDir
  withTempDirectory $ \ _ -> do
    -- FIXME use cabal-file
    dl <- cmdBool "wget" ["--quiet", "https://hackage.haskell.org/package" </> display pkgid </> file]
    if not dl
      then return False
      else do
      revised <- grep_ "x-revision" file
      when revised $
        renameFile file $ dir </> display pkgid <.> "cabal"
      return revised

data RpmStage = Binary | Source | Prep
  deriving Eq

instance Show RpmStage where
  show Binary = "binary"
  show Source = "source"
  show Prep = "prep"

rpmbuild :: Bool -> RpmStage -> FilePath -> IO ()
rpmbuild quiet mode spec = do
  let rpmCmd = case mode of
        Binary -> "a"
        Source -> "s"
        Prep -> "p"
  cwd <- getCurrentDirectory
  gitDir <- isGitDir "."
  let rpmdirs_override =
        [ "--define="++ mcr +-+ cwd | gitDir,
          mcr <- ["_builddir", "_rpmdir", "_srcrpmdir", "_sourcedir"]]
  let args = ["-b" ++ rpmCmd] ++ ["--nodeps" | mode == Prep] ++
             rpmdirs_override ++ [spec]
  if not quiet then
    cmd_ "rpmbuild" args
    else do
    putStr $ "rpmbuild" +-+ show mode ++ ": "
#if MIN_VERSION_simple_cmd(0,2,2)
    -- may hang for build
    (ret, out) <- cmdStderrToStdout "rpmbuild" args
    case ret of
      ExitSuccess -> putStrLn "done"
      ExitFailure _ -> error' $ "\n" ++ dropToPrefix "+ /usr/bin/chmod -Rf" out
  where
    dropToPrefix :: String -> String -> String
    dropToPrefix _ "" = ""
    dropToPrefix prefix cs =
      let ls = lines cs
          rest = dropWhile (not . (prefix `isPrefixOf`)) ls
      in unlines (if null rest then tail ls else tail rest)
#else
    cmdSilent "rpmbuild" args
    putStrLn "done"
#endif

cabalUpdate :: IO ()
cabalUpdate = do
  home <- getEnv "HOME"
  let dir = home </> ".cabal/packages/hackage.haskell.org"
  done <- checkTimestamp $ dir </> "01-index.timestamp"
  unless done $ do
    done' <- checkTimestamp $ dir </> "01-index.cache"
    unless done' cabalUpdateCmd
  where
    checkTimestamp tsfile = do
      haveFile <- doesFileExist tsfile
      if haveFile then do
        ts <- getModificationTime tsfile
        t <- getCurrentTime
        -- less than 3 hours
        when (diffUTCTime t ts > 10000) cabalUpdateCmd
        return True
        else
        return False

    cabalUpdateCmd :: IO ()
    cabalUpdateCmd = do
      putStrLn "Running 'cabal update'"
      cmd_ "cabal" ["update", "-v0"]

cabal :: String -> [String] -> IO [String]
cabal c args = do
  cabalUpdate
  cmdLines "cabal" (c:args)

cabal_ :: String -> [String] -> IO ()
cabal_ c args = do
  cabalUpdate
  cmd_ "cabal" (c:args)


tryUnpack :: PackageIdentifier -> Bool -> Bool
          -> IO (FilePath, Maybe FilePath) -- (cabalfile, mtmpdir)
tryUnpack pkgid revise keep = do
  let dir = display pkgid
  isdir <- doesDirectoryExist dir
  if isdir
    then do
    mcabal <- withCurrentDirectory dir $ checkForCabalFile (Just (pkgName pkgid))
    if isJust mcabal then do
      pth <- tryFindPackageDesc dir
      return (pth, Nothing)
      else
      error $ "could not find" +-+ display (pkgName pkgid) <.> "cabal"
    else do
    cwd <- getCurrentDirectory
    mtmpdir <- if keep then return Nothing
      else do
      tmpdir <- mktempdir
      setCurrentDirectory tmpdir
      return $ Just tmpdir
    cabal_ "unpack" $ ["-v0"] ++ ["--pristine" | not revise] ++ [display pkgid]
    pth <- tryFindPackageDesc dir
    setCurrentDirectory cwd
    return (fromMaybe "" mtmpdir </> pth, mtmpdir)

latestPackage :: Maybe Stream -> PackageName -> IO PackageIdentifier
latestPackage (Just Hackage) pkg = latestHackage pkg
latestPackage mstream pkg = do
  stk <- latestStackage mstream pkg
  case stk of
    Just pkgid -> return pkgid
    Nothing -> latestHackage pkg

-- use cabal-file when it parses preferred-versions
latestHackage :: PackageName -> IO PackageIdentifier
latestHackage pkgname = do
  let pkg = display pkgname
  contains_pkg <- cabal "list" ["-v0", pkg]
  let top = dropWhile (/= "*" +-+ pkg) contains_pkg
  if null top
    then error $ pkg +-+ "hackage not found"
    else do
    let field = "    Default available version: "
    let avails = map (removePrefix field) $ filter (isPrefixOf field) top
    if null avails
      then error $ pkg +-+ "latest available version not found"
      else do
      let res = pkg ++ "-" ++ head avails
      putStrLn $ res +-+ "in Hackage"
      return $ PackageIdentifier (mkPackageName pkg) $ readVersion $ head avails

checkForSpecFile :: Maybe PackageName -> IO (Maybe FilePath)
checkForSpecFile mpkg = do
  allSpecs <- filesWithExtension "." ".spec"
  -- emacs makes ".#*.spec" tmp files
  let predicate = maybe ((/= '.') . head) (\ pkg -> (`elem` [pkg <.> "spec", "ghc-" ++ pkg <.> "spec"])) (display <$> mpkg)
      specs = filter predicate allSpecs
  when (specs /= allSpecs && isNothing mpkg) $
    putStrLn "Warning: dir contains a hidden spec file"
  case specs of
    [one] -> return $ Just one
    [] -> return Nothing
    _ -> error' "more than one spec file found!"

checkForCabalFile :: Maybe PackageName -> IO (Maybe FilePath)
checkForCabalFile mpkg = do
  allCabals <- filesWithExtension "." ".cabal"
  let predicate = maybe (const True) (\ pkg -> (== pkg <.> "cabal")) (display <$> mpkg)
      cabals = filter predicate allCabals
  case cabals of
    [one] -> return $ Just one
    [] -> return Nothing
    _ -> error' "more than one cabal file found!"

checkForPkgCabalFile :: PackageIdentifier -> IO (Maybe FilePath)
checkForPkgCabalFile pkgid = do
  let pkg = pkgName pkgid
      cabalfile = display pkg <.> "cabal"
  pkgcabal <- doesFileExist cabalfile
  if pkgcabal
    then return $ Just cabalfile
    else do
    exists <- doesDirectoryExist $ display pkgid
    if exists
      then fileWithExtension (display pkgid) ".cabal"
      else return Nothing

pkgSpecPkgData :: Flags -> Maybe PackageName -> Bool -> Bool -> IO PackageData
pkgSpecPkgData flags mpkg revise keep = do
  mspec <- checkForSpecFile mpkg
  case mspec of
    Just spec -> specPackageData spec
    Nothing -> do
      mcabal <- checkForCabalFile mpkg
      case mcabal of
        Just cabalfile -> do
          (pkgDesc, docs, licenses) <- simplePackageDescription flags cabalfile
          return $ PackageData Nothing docs licenses pkgDesc
        Nothing ->
          case mpkg of
            Just pkg -> prepStreamPkg flags Nothing defaultLTS pkg revise keep
            Nothing -> do
              cwd <- getCurrentDirectory
              let trydir = simpleParse (takeFileName cwd)
              case trydir of
                Just pdir | pkgVersion pdir == nullVersion ->
                              prepare flags (streamPkgToPVS Nothing trydir) revise keep
                _ -> error' "package not found for directory"
  where
    specPackageData :: FilePath -> IO PackageData
    specPackageData spec = do
      assertFileNonEmpty spec
      cabalfile <- cabalFromSpec spec
      (pkgDesc, docs, licenses) <- simplePackageDescription flags cabalfile
      return $ PackageData (Just spec) docs licenses pkgDesc
      where
        cabalFromSpec :: FilePath -> IO FilePath
        cabalFromSpec specFile = do
          namever <- removePrefix "ghc-" . head <$> rpmspec ["--srpm"] (Just "%{name}-%{version}") specFile
          case simpleParse namever of
            Nothing -> error "pkgid could not be parsed"
            Just pkgid -> bringTarball pkgid revise (Just specFile)
          dExists <- doesDirectoryExist namever
          if dExists
            then do
            specTime <- modificationTime <$> getFileStatus specFile
            dirTime <- accessTime <$> getFileStatus namever
            when (specTime > dirTime) $ do
              rpmbuild True Prep specFile
              dExists' <- doesDirectoryExist namever
              when dExists' $ cmd_ "touch" [namever]
            else
            rpmbuild True Prep specFile
          tryFindPackageDesc namever

-- findSpecFile :: PackageDescription -> RpmFlags -> IO (FilePath, Bool)
-- findSpecFile pkgDesc flags = do
--   pkgname <- findPkgName pkgDesc flags
--   let specfile = pkgname <.> "spec"
--   exists <- doesFileExist specfile
--   return (specfile, exists)

data PackageData =
  PackageData { specFilename :: Maybe FilePath
              , docFilenames :: [FilePath]
              , licenseFilenames :: [FilePath]
              , packageDesc :: PackageDescription
              }

prepPkgId :: Flags -> Maybe FilePath -> PackageIdentifier -> Bool -> Bool
          -> IO PackageData
prepPkgId flags mspec pkgid revise keep = do
  (cabalfile, mtmp) <- tryUnpack pkgid revise keep
  (pkgDesc, docs, licenses) <- simplePackageDescription flags cabalfile
  unless keep $ maybe (return ()) removeDirectoryRecursive mtmp
  return $ PackageData mspec docs licenses pkgDesc

prepStreamPkg :: Flags -> Maybe FilePath -> Stream -> PackageName -> Bool -> Bool
              -> IO PackageData
prepStreamPkg flags mspec stream pkg revise keep = do
  pkgid <- latestPackage (Just stream) pkg
  mcabal <- checkForPkgCabalFile pkgid
  case mcabal of
    Just cabalfile -> do
      (pkgDesc, docs, licenses) <- simplePackageDescription flags cabalfile
      return $ PackageData mspec docs licenses pkgDesc
    Nothing -> prepPkgId flags mspec pkgid revise keep

-- Nothing means package in cwd
prepare :: Flags -> Maybe PackageVersionSpecifier -> Bool -> Bool
        -> IO PackageData
prepare flags Nothing revise keep = pkgSpecPkgData flags Nothing revise keep
-- Something implies either new packaging or some existing spec file in dir
prepare flags (Just pvs) revise keep =
  case pvs of
    PVPackageName pkg -> pkgSpecPkgData flags (Just pkg) revise keep
    PVPackageId pkgid -> do
      mspec <- checkForSpecFile $ Just (pkgName pkgid)
      mcabal <- checkForPkgCabalFile pkgid
      case mcabal of
        Just cabalfile -> do
          (pkgDesc, docs, licenses) <- simplePackageDescription flags cabalfile
          return $ PackageData mspec docs licenses pkgDesc
        Nothing -> prepPkgId flags mspec pkgid revise keep
    PVStreamPackage stream Nothing -> do
      mspec <- checkForSpecFile Nothing
      case mspec of
        Nothing -> do
          cwd <- getCurrentDirectory
          let trydir = simpleParse (takeFileName cwd)
          case trydir of
            Just pdir | pkgVersion pdir == nullVersion ->
                          prepare flags (streamPkgToPVS (Just stream) trydir) revise keep
            _ -> error' "package not found"
        Just spec -> do
          let pkg = mkPackageName $ removePrefix "ghc-" $ takeBaseName spec
          prepStreamPkg flags (Just spec) stream pkg revise keep
    PVStreamPackage stream (Just pkg) -> do
      mspec <- checkForSpecFile (Just pkg)
      prepStreamPkg flags mspec stream pkg revise keep

-- redundant mdir was earlier for update
patchSpec :: Bool -> Maybe FilePath -> FilePath -> FilePath -> IO ()
patchSpec dryrun mdir oldspec newspec = do
  diff <- cmdIgnoreErr "diff" ["-u2", "-I", "- spec file generated by cabal-rpm", "-I", "Fedora Haskell SIG <haskell@lists.fedoraproject.org>", oldspec, newspec] "" >>= cmdIgnoreErr "sed" ["-e", "s%.Cblrpm/%%", "-e", "s/.cblrpm//"] . dropChangelog
  putStrLn diff
  unless dryrun $ do
    putStrLn ""
    out <- cmdIgnoreErr "patch" opts diff
    putStrLn out
  where
    opts = ["--fuzz=1"] ++ ["-p" ++ show n | let n = count '/' (removePrefix ".Cblrpm/" newspec)] ++ maybe [] (\ d -> ["-d", d]) mdir

    count :: Eq a => a -> [a] -> Int
    count x =  length . filter (==x)

dropChangelog :: String -> String
dropChangelog cs =
  let ls = lines cs in
  if " %changelog" `elem` ls then
    let rest = (dropWhileEnd ("@@ " `isPrefixOf`) . dropWhileEnd (== " ") . takeWhile (/= " %changelog")) ls in
      if length rest > 2 then unlines rest else ""
    else cs

packageManager :: IO String
packageManager = do
  havednf <- optionalProgram "dnf"
  if havednf
    then return "dnf"
    else requireProgram "yum" >> return "yum"

repoquery :: [String] -> String -> IO String
repoquery args key = do
  havednf <- optionalProgram "dnf"
  let (prog, subcmd) = if havednf then ("dnf", ["repoquery", "-q"]) else ("repoquery", [])
  sudo prog (subcmd ++ args ++ [key])

rpmInstall :: Bool -> [String] -> IO ()
rpmInstall _ [] = return ()
rpmInstall yes rpms = do
  pkginstaller <- packageManager
  let (inst, arg) = if pkginstaller == "dnf" then ("dnf", "install") else ("yum", "localinstall")
  tty <- hIsTerminalDevice stdout
  sudo_ inst $ ["-y" | yes || not tty] ++ [arg] ++ rpms

editSpecField :: String -> String -> FilePath -> IO ()
editSpecField field new spec =
  cmd_ "sed" ["-i", "-e s/^\\(" ++ field ++ ":\\s\\+\\).*/\\1" ++ new ++ "/", spec]

getSpecField :: String -> FilePath -> IO String
getSpecField field spec =
  cmd "rpmspec" ["-q", "--qf", "%{" ++ field ++ "}", "--srpm", "--undefine", "dist", spec]