{-# LANGUAGE CPP, NamedFieldPuns, RecordWildCards #-}

-- | Code to deal with configuration information, including gathering it from the host environment.
--   Also deals with command line arguments.

-- Disabling some stuff until we can bring it back up after the big transition [2013.05.28]:
#define DISABLED

module HSBencher.Internal.Config
       ( -- * Configurations
         getConfig, augmentResultWithConfig,
         addPlugin, 

         -- * Command line options
         Flag(..), all_cli_options
       )
       where

import Control.Monad.Reader
import qualified Data.Map as M
import Data.Time.Clock (getCurrentTime, diffUTCTime)
import Data.Time.Clock.POSIX (utcTimeToPOSIXSeconds)
import Data.Monoid
import Data.Dynamic
import GHC.Conc (getNumProcessors)
import System.Environment (getArgs, getEnv, getEnvironment)
import System.Console.GetOpt (getOpt, ArgOrder(Permute), OptDescr(Option), ArgDescr(..))
import System.IO (Handle, hPutStrLn, stderr, openFile, hClose, hGetContents, hIsEOF, hGetLine,
                  IOMode(..), BufferMode(..), hSetBuffering)
import qualified System.IO.Streams as Strm
import qualified System.IO.Streams.Concurrent as Strm
import qualified System.IO.Streams.Process as Strm
import qualified System.IO.Streams.Combinators as Strm

import HSBencher.Types
import HSBencher.Internal.Utils
import HSBencher.Methods.Builtin
import HSBencher.Internal.MeasureProcess

----------------------------------------------------------------------------------------------------

-- | Command line flags to the benchmarking executable.
data Flag = ParBench 
          | BenchsetName (String)
          | BinDir FilePath
          | NoRecomp | NoCabal | NoClean
          | ShortRun | KeepGoing | NumTrials String
          | SkipTo String | RunOnly Int | RetryFailed Int
          | RunID String | CIBuildID String | ForceHostName String
          | CabalPath String | GHCPath String                               
          | ShowHelp | ShowVersion | ShowBenchmarks
          | DisablePlug String
  deriving (Show)
--  deriving (Eq,Ord,Show,Read)

-- | Command line options.
core_cli_options :: (String, [OptDescr Flag])
core_cli_options = 
     ("\n Command Line Options:",
      [
#ifndef DISABLED        
        Option ['p'] ["par"] (NoArg ParBench) 
        "Build benchmarks in parallel (run in parallel too if SHORTRUN=1)."
#endif
        Option [] ["no-recomp"] (NoArg NoRecomp)
        "Don't perform any compilation of benchmark executables.  Implies -no-clean."
      , Option [] ["no-clean"] (NoArg NoClean)
        "Do not clean pre-existing executables before beginning."
      , Option [] ["shortrun"] (NoArg ShortRun)
        "Elide command line args to benchmarks to perform a testing rather than benchmarking run."
      , Option ['k'] ["keepgoing"] (NoArg KeepGoing)
        "Keep executing even after a build or run fails (default false)"
#ifndef DISABLED 
      , Option [] ["no-cabal"] (NoArg NoCabal)
        "A shortcut to remove Cabal from the BuildMethods"
#endif
      , Option [] ["with-cabal-install"] (ReqArg CabalPath "PATH")
        "Set the version of cabal-install to use for the cabal BuildMethod."
      , Option [] ["with-ghc"] (ReqArg GHCPath "PATH")
        "Set the path of the ghc compiler for the ghc BuildMethod."

      , Option [] ["trials"] (ReqArg NumTrials "NUM")
        "The number of times to run each benchmark."

      , Option [] ["runid"] (ReqArg RunID "NUM")
        "Force run ID to be a specific string; useful for completing failed runs"
      , Option [] ["buildid"] (ReqArg CIBuildID "STR")
        "Set the build ID used by the continuous integration system."

      , Option [] ["hostname"] (ReqArg ForceHostName "STR")
        "Force the hostname to be set to STR rather than read from the system."

      , Option [] ["skipto"] (ReqArg (SkipTo ) "NUM")
        "Skip ahead to a specific point in the configuration space."
      , Option [] ["runonly"] (ReqArg (mkPosIntFlag RunOnly) "NUM")
        "Run only NUM configurations, from wherever we start."
      , Option [] ["retry"] (ReqArg (mkPosIntFlag RetryFailed) "NUM")
        "Counter nondeterminism while debugging.  Retry failed tests NUM times."

      , Option ['h'] ["help"] (NoArg ShowHelp)
        "Show this help message and exit."

      , Option ['l'] ["list-benchmarks"] (NoArg ShowBenchmarks)
        "Show names of benchmarks, match them by substring in cmdln arg."

      , Option ['d'] ["disable"] (ReqArg DisablePlug "STR")
        "Disable a plugin by name, even if support for it was compiled in."

      , Option ['V'] ["version"] (NoArg ShowVersion)
        "Show the version and exit"
      , Option [] ["name"] (ReqArg BenchsetName "NAME") "Name for created/discovered table in the backend."
     ])

-- | Check that the flag setting is valid.
mkPosIntFlag :: (Read a, Ord a, Num a) => (a -> Flag) -> String -> Flag
mkPosIntFlag constructor str = 
  case reads str of
    (n,_):_ | n >= 1    -> constructor n
            | otherwise -> error$ "--runonly must be positive: "++str
    [] -> error$ "--runonly given bad argument: "++str


all_cli_options :: [(String, [OptDescr Flag])]
all_cli_options = [core_cli_options]

----------------------------------------------------------------------------------------------------

-- | Fill in "static" fields of a BenchmarkResult row based on the `Config` data.
augmentResultWithConfig :: Config -> BenchmarkResult -> IO BenchmarkResult
augmentResultWithConfig Config{..} base = do
  -- ghcVer <- runSL$ ghc ++ " -V"
  -- let ghcVer' = collapsePrefix "The Glorious Glasgow Haskell Compilation System," "GHC" ghcVer
  datetime <- getCurrentTime
  uname    <- runSL "uname -a"
  lspci    <- runLines "lspci"
  whos     <- runLines "who"
  let newRunID = (hostname ++ "_" ++ show startTime)
  let (branch,revision,depth) = gitInfo      
  return $
    base
    { _HOSTNAME      = hostname
    , _RUNID         = case runID of
                        Just r -> r
                        Nothing -> newRunID
    , _CI_BUILD_ID   = case ciBuildID of
                        Just r -> r
                        Nothing -> ""
    , _DATETIME      = show datetime
    , _TRIALS        = trials
    , _ENV_VARS      = show envs 
    , _BENCH_VERSION = show$ snd benchversion
    , _BENCH_FILE    = fst benchversion
    , _UNAME         = uname
    , _LSPCI         = unlines lspci
    , _GIT_BRANCH    = branch   
    , _GIT_HASH      = revision 
    , _GIT_DEPTH     = depth
    , _WHO           = unlines whos
    }

-- | This abstracts over the actions we need to take to properly add
-- an additional plugin to the `Config`.
addPlugin :: Plugin p => p -> PlugConf p -> Config -> Config
addPlugin plug pconf conf = 
  conf { plugIns = SomePlugin plug : plugIns conf
       , plugInConfs = M.insert (plugName plug) (SomePluginConf plug pconf) $ 
                       plugInConfs conf }

-- | Retrieve the (default) configuration from the environment, it may
-- subsequently be tinkered with.  This procedure should be idempotent.
getConfig :: [Flag] -> [Benchmark DefaultParamMeaning] -> IO Config
getConfig cmd_line_options benches = do
  hostname <- runSL$ "hostname -s"
  t0 <- getCurrentTime
  let startTime = round (utcTimeToPOSIXSeconds t0)
  env      <- getEnvironment

  -- There has got to be a simpler way!
  branch   <- runSL  "git name-rev --name-only HEAD"
  revision <- runSL  "git rev-parse HEAD"
  -- Note that this will NOT be newline-terminated:
  hashes   <- runLines "git log --pretty=format:'%H'"

  let       
      -- Read an ENV var with default:
      get v x = case lookup v env of 
		  Nothing -> x
		  Just  s -> s
      logFile = "bench_" ++ hostname ++ ".log"
      resultsFile = "results_" ++ hostname ++ ".dat"      

  case get "GENERIC" "" of 
    "" -> return ()
    s  -> error$ "GENERIC env variable not handled yet.  Set to: " ++ show s
  
  maxthreads <- getNumProcessors

  backupResults resultsFile logFile

  rhnd <- openFile resultsFile WriteMode 
  lhnd <- openFile logFile     WriteMode

  hSetBuffering rhnd NoBuffering
  hSetBuffering lhnd NoBuffering  
  
  resultsOut <- Strm.unlines =<< Strm.handleToOutputStream rhnd
  logOut     <- Strm.unlines =<< Strm.handleToOutputStream lhnd
  stdOut     <- Strm.unlines Strm.stdout

  let -- Messy way to extract the benchlist version:
      -- ver = case filter (isInfixOf "ersion") (lines benchstr) of 
      --         (h:_t) -> read $ (\ (h:_)->h) $ filter isNumber (words h)
      --         []    -> 0
      -- This is our starting point BEFORE processing command line flags:
      base_conf = Config 
           { hostname, startTime
           , shortrun       = False
           , doClean        = True
           , benchsetName   = Nothing
--	   , trials         = read$ get "TRIALS"    "1"
	   , trials         = 1
	   , skipTo         = Nothing
	   , runOnly        = Nothing
	   , retryFailed    = Nothing
	   , runID          = Nothing
	   , ciBuildID      = Nothing                              
           , pathRegistry   = M.empty
--	   , benchlist      = parseBenchList benchstr
--	   , benchversion   = (benchF, ver)
           , benchlist      = benches
	   , benchversion   = ("",0)
	   , maxthreads     = maxthreads
--	   , threadsettings = parseIntList$ get "THREADS" (show maxthreads)
           , runTimeOut     = Just defaultTimeout
	   , keepgoing      = False
	   , resultsFile, logFile, logOut, resultsOut, stdOut         
--	   , outHandles     = Nothing
           , envs           = read $ get "ENVS" "[[]]"
           , gitInfo        = (trim branch, trim revision, length hashes)
           -- This is in priority order:                   
           , buildMethods   = [cabalMethod, makeMethod, ghcMethod]
           , argsBeforeFlags = True
           , harvesters = selftimedHarvester       `mappend`
                          ghcProductivityHarvester `mappend`
                          ghcMemFootprintHarvester `mappend`
                          ghcAllocRateHarvester    `mappend`
                          jittimeHarvester
           , plugIns = []
           , plugInConfs = M.empty
	   }

  -- Process command line arguments to add extra cofiguration information:
  let 
      doFlag (BenchsetName name) r = r { benchsetName= Just name }
      doFlag (CabalPath p) r = r { pathRegistry= M.insert "cabal" p (pathRegistry r) }
      doFlag (GHCPath   p) r = r { pathRegistry= M.insert "ghc"   p (pathRegistry r) }

      doFlag ShortRun  r = r { shortrun= True }
      doFlag KeepGoing r = r { keepgoing= True }
      doFlag (NumTrials s) r = r { trials=
                                    case reads s of
                                      (n,_):_ -> n
                                      [] -> error$ "--trials given bad argument: "++s }
      doFlag (SkipTo s) r = r { skipTo=
                                    case reads s of
                                      (n,_):_ | n >= 1    -> Just n
                                              | otherwise -> error$ "--skipto must be positive: "++s
                                      [] -> error$ "--skipto given bad argument: "++s }
      doFlag (RunOnly n) r = r { runOnly= Just n }
      doFlag (RetryFailed n) r = r { retryFailed= Just n }
      doFlag (RunID s) r = r { runID= Just s }
      doFlag (ForceHostName s) r = r { hostname= s }
      doFlag (CIBuildID s) r = r { ciBuildID= Just s }

      -- Ignored options:
      doFlag ShowHelp r = r
      doFlag ShowVersion r = r
      doFlag ShowBenchmarks r = r
      doFlag (DisablePlug _) r = r
      doFlag NoRecomp r = r
      doFlag NoCabal  r = r
      doFlag NoClean  r = r { doClean = False }
      doFlag ParBench r = r
      --------------------
      finalconf = foldr ($) base_conf (map doFlag cmd_line_options)

--  runReaderT (log$ "Read list of benchmarks/parameters from: "++benchF) finalconf
  return finalconf