{- Checks system configuration and generates Build/SysConfig and Build/Version. -}

{-# OPTIONS_GHC -fno-warn-tabs #-}

module Build.Configure where

import Build.TestConfig
import Build.Version
import Utility.SafeCommand
import Utility.ExternalSHA
import Utility.Env.Basic
import qualified Git.Version
import Utility.Directory

import Control.Monad
import Control.Applicative
import Prelude

tests :: [TestCase]
tests =
	[ TestCase "UPGRADE_LOCATION" getUpgradeLocation
	, TestCase "git" $ testCmd "git" "git --version >/dev/null"
	, TestCase "git version" getGitVersion
	, testCp "cp_a" "-a"
	, testCp "cp_p" "-p"
	, testCp "cp_preserve_timestamps" "--preserve=timestamps"
	, testCp "cp_reflink_auto" "--reflink=auto"
	, TestCase "xargs -0" $ testCmd "xargs_0" "xargs -0 </dev/null"
	, TestCase "rsync" $ testCmd "rsync" "rsync --version >/dev/null"
	, TestCase "curl" $ testCmd "curl" "curl --version >/dev/null"
	, TestCase "bup" $ testCmd "bup" "bup --version >/dev/null"
	, TestCase "nice" $ testCmd "nice" "nice true >/dev/null"
	, TestCase "ionice" $ testCmd "ionice" "ionice -c3 true >/dev/null"
	, TestCase "nocache" $ testCmd "nocache" "nocache true >/dev/null"
	, TestCase "gpg" $ maybeSelectCmd "gpg"
		[ ("gpg", "--version >/dev/null")
		, ("gpg2", "--version >/dev/null") ]
	, TestCase "lsof" $ findCmdPath "lsof" "lsof"
	, TestCase "git-remote-gcrypt" $ findCmdPath "gcrypt" "git-remote-gcrypt"
	, TestCase "ssh connection caching" getSshConnectionCaching
	] ++ shaTestCases
	[ (1, "da39a3ee5e6b4b0d3255bfef95601890afd80709")
	, (256, "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855")
	, (512, "cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e")
	, (224, "d14a028c2a3a2bc9476102bb288234c415a2b01f828ea62ac5b3e42f")
	, (384, "38b060a751ac96384cd9327eb1b1e36a21fdb71114be07434c0cc7bf63f6e1da274edebfe76f65fbd51ad2f14898b95b")
	]

{- shaNsum are the program names used by coreutils. Some systems
 - install these with 'g' prefixes.
 -
 - On some systems, shaN is used instead, but on other
 - systems, it might be "hashalot", which does not produce
 - usable checksums. Only accept programs that produce
 - known-good hashes when run on files. -}
shaTestCases :: [(Int, String)] -> [TestCase]
shaTestCases l = map make l
  where
	make (n, knowngood) = TestCase key $ 
		Config key . MaybeStringConfig <$> search (shacmds n)
	  where
		key = "sha" ++ show n
		search [] = return Nothing
		search (c:cmds) = do
			sha <- externalSHA c n "/dev/null"
			if sha == Right knowngood
				then return $ Just c
				else search cmds
	
	shacmds n = concatMap (\x -> [x, 'g':x]) $
		map (\x -> "sha" ++ show n ++ x) ["sum", ""]

tmpDir :: String
tmpDir = "tmp"

testFile :: String
testFile = tmpDir ++ "/testfile"

testCp :: ConfigKey -> String -> TestCase
testCp k option = TestCase cmd $ testCmd k cmdline
  where
	cmd = "cp " ++ option
	cmdline = cmd ++ " " ++ testFile ++ " " ++ testFile ++ ".new"

getUpgradeLocation :: Test
getUpgradeLocation = do
	e <- getEnv "UPGRADE_LOCATION"
	return $ Config "upgradelocation" $ MaybeStringConfig e

getGitVersion :: Test
getGitVersion = go =<< getEnv "FORCE_GIT_VERSION"
  where
	go (Just s) = return $ Config "gitversion" $ StringConfig s
	go Nothing = do
		v <- Git.Version.installed
		let oldestallowed = Git.Version.normalize "1.7.1.0"
		when (v < oldestallowed) $
			error $ "installed git version " ++ show v ++ " is too old! (Need " ++ show oldestallowed ++ " or newer)"
		return $ Config "gitversion" $ StringConfig $ show v

getSshConnectionCaching :: Test
getSshConnectionCaching = Config "sshconnectioncaching" . BoolConfig <$>
	boolSystem "sh" [Param "-c", Param "ssh -o ControlPersist=yes -V >/dev/null 2>/dev/null"]

setup :: IO ()
setup = do
	createDirectoryIfMissing True tmpDir
	writeFile testFile "test file contents"

cleanup :: IO ()
cleanup = removeDirectoryRecursive tmpDir

run :: [TestCase] -> IO ()
run ts = do
	setup
	config <- runTests ts
	v <- getEnv "CROSS_COMPILE"
	case v of
		Just "Android" -> writeSysConfig $ androidConfig config
		_ -> writeSysConfig config
	writeVersion =<< getVersion
	cleanup

{- Hard codes some settings to cross-compile for Android. -}
androidConfig :: [Config] -> [Config]
androidConfig c = overrides ++ filter (not . overridden) c
  where
	overrides = 
		[ Config "cp_reflink_auto" $ BoolConfig False
		, Config "curl" $ BoolConfig False
		, Config "sha224" $ MaybeStringConfig Nothing
		, Config "sha384" $ MaybeStringConfig Nothing
		]
	overridden (Config k _) = k `elem` overridekeys
	overridekeys = map (\(Config k _) -> k) overrides