{- Checks system configuration and generates SysConfig.hs. -}

module Build.Configure where

import System.Directory
import Data.List
import System.Process
import Control.Applicative
import System.FilePath
import System.Environment (getArgs)
import Data.Maybe
import Control.Monad.IfElse
import Control.Monad
import Data.Char

import Build.TestConfig
import Build.Version
import Utility.SafeCommand
import Utility.Monad
import Utility.ExternalSHA
import Utility.Env
import qualified Git.Version

tests :: [TestCase]
tests =
	[ TestCase "version" getVersion
	, TestCase "UPGRADE_LOCATION" getUpgradeLocation
	, TestCase "git" $ requireCmd "git" "git --version >/dev/null"
	, TestCase "git version" getGitVersion
	, testCp "cp_a" "-a"
	, testCp "cp_p" "-p"
	, testCp "cp_reflink_auto" "--reflink=auto"
	, TestCase "xargs -0" $ requireCmd "xargs_0" "xargs -0 </dev/null"
	, TestCase "rsync" $ requireCmd "rsync" "rsync --version >/dev/null"
	, TestCase "curl" $ testCmd "curl" "curl --version >/dev/null"
	, TestCase "wget" $ testCmd "wget" "wget --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 = 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
	args <- getArgs
	setup
	config <- runTests ts
	if args == ["Android"]
		then writeSysConfig $ androidConfig config
		else writeSysConfig config
	cleanup
	whenM isReleaseBuild $
		cabalSetup "git-annex.cabal"

{- 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