{-# LANGUAGE DeriveDataTypeable, GeneralizedNewtypeDeriving   #-}
module Shake where

import Prelude hiding ((*>))

import Development.Shake
import Development.Shake.FilePath
import Development.Shake.Classes
import Control.Monad
import qualified Data.Map as M
import Data.Functor
import Data.List

import Paths hiding (Hash)
import ParentMap
import BenchmarksInCSV
import qualified BenchmarkSettings as S

{- Global settings -}
cGRAPH_HISTORY :: Integer
cGRAPH_HISTORY = 50

git :: (CmdResult b) => String -> [String] -> Action b
git gitcmd args = do
    cmd (Traced $ "git " ++ gitcmd) (words "git -C repository" ++ gitcmd : args)

self :: (CmdResult b) => String -> [String] -> Action b
self name args = do
    -- orderOnly ["gipeda"]
    cmd (Traced name) "./gipeda" name args

gitRange :: Action String
gitRange = do
    s <- liftIO $ S.readSettings "settings.yaml"
    let first = S.start s
    [head] <- readFileLines "site/out/head.txt"
    return $ first ++ ".." ++ head

needIfThere :: [FilePath] -> Action [FilePath]
needIfThere files = do
    existing <- filterM doesFileExist files
    need existing
    return existing

findPred, findPredOrSelf :: ParentMap -> Hash -> Action (Maybe Hash)
findPredOrSelf m h = do
    ex <- doesFileExist (logsOf h)
    if ex then return (Just h)
          else findPred m h
findPred m h = case M.lookup h m of 
    Just h' -> findPredOrSelf m h'
    Nothing -> return Nothing

findRecent :: ParentMap -> Integer -> FilePath -> Action [FilePath]
findRecent _ 0 _ = return []
findRecent m n h = do
    pM <- findPred m h
    (h:) <$> case pM of
        Nothing -> return []
        Just p ->  findRecent m (n-1) p

newtype LimitRecent = LimitRecent ()
    deriving (Show,Typeable,Eq,Hashable,Binary,NFData)

shakeMain :: IO ()
shakeMain = shakeArgs shakeOptions $ do

{-
    "gipeda" *> \out ->  do
        sources <- getDirectoryFiles "src" ["*.hs"]
        need (map ("src" </>) sources)
        cmd "ghc -isrc --make -O src/gipeda.hs -o" out
    want ["gipeda"]
-}

    getLimitRecent <- addOracle $ \(LimitRecent _) -> do
        need ["settings.yaml"]
        S.limitRecent <$> liftIO (S.readSettings "settings.yaml")

    "reports" ~> do
        range <- gitRange
        Stdout range <- git "log" ["--format=%H",range]
        let hashes = words range
        withLogs <- filterM (doesFileExist . logsOf) hashes
        need $ map reportOf withLogs
    want ["reports"]

    "summaries" ~> do
        range <- gitRange
        Stdout range <- git "log" ["--format=%H",range]
        let hashes = words range
        withLogs <- filterM (doesFileExist . logsOf) hashes
        need $ map summaryOf withLogs
    want ["summaries"]

    "site/out/head.txt" *> \ out -> do
        alwaysRerun
        Stdout stdout <- git "rev-parse" ["master"]
        writeFileChanged out stdout
     

    "site/out/history.csv" *> \out -> do
        range <- gitRange
        Stdout stdout <- git "log" ["--format=%H;%P",range]
        writeFileChanged out stdout
    want ["site/out/history.csv"]

    history' <- newCache $ \() -> do
         orderOnly ["site/out/history.csv"]
         liftIO $ ssvFileToMap "site/out/history.csv"
    let history = history' ()
    let pred h = do { hist <- history; findPred hist h }
    let predOrSelf h = do { hist <- history; findPredOrSelf hist h }
    let recent n h = do { hist <- history; findRecent hist n h }

    "site/out/latest.txt" *> \ out -> do
        [head] <- readFileLines "site/out/head.txt"
        latestM <- predOrSelf head
        case latestM of
           Just latest -> 
                writeFileChanged out latest
           Nothing -> 
                fail "Head has no parent with logs?"

    "graphs" ~> do
        [latest] <- readFileLines "site/out/latest.txt"
        need [resultsOf latest]
        b <- liftIO $ benchmarksInCSVFile (resultsOf latest)
        need (map graphFile b)
    want ["graphs"]

    "site/out/results/*.csv" *> \out -> do
        let hash = takeBaseName out
        need [logsOf hash]
        Stdout csv <- cmd "./log2csv" (logsOf hash)
        writeFile' out csv

    "site/out/graphs//*.json" *> \out -> do
        let bench = dropDirectory1 (dropDirectory1 (dropDirectory1 (dropExtension out)))

        [latest] <- readFileLines "site/out/latest.txt"
        limitRecent <- getLimitRecent (LimitRecent ())
        r <- recent limitRecent latest
        need (map resultsOf r)

        Stdout json <- self "GraphReport" (bench : r)
        writeFile' out json

    "site/out/reports/*.json" *> \out -> do
        let hash = takeBaseName out
        need [resultsOf hash]

        pred <- pred hash
        need [resultsOf h | Just h <- return pred]

        Stdout json <- self "RevReport" (hash : [h | Just h <- return pred])
        writeFile' out json

    "site/out/summaries/*.json" *> \out -> do
        let hash = takeBaseName out
        need [reportOf hash]

        Stdout json <- self "Summary" [hash]
        writeFile' out json

    "site/out/latest-summaries.json" *> \out -> do
        [latest] <- readFileLines "site/out/latest.txt"
        r <- recent cGRAPH_HISTORY latest
        need (map summaryOf r)

        Stdout json <- self "IndexReport" r
        writeFile' out json
    want ["site/out/latest-summaries.json"]

    "site/out/benchNames.json" *> \out -> do
        [latest] <- readFileLines "site/out/latest.txt"
        need [resultsOf latest]
        b <- liftIO $ benchmarksInCSVFile (resultsOf latest)

        need ["settings.yaml"]

        Stdout json <- self "BenchNames" (nub b)
        writeFile' out json
    want ["site/out/benchNames.json"]
        


    "site/out/all-summaries.json" *> \out -> do
        range <- gitRange
        Stdout range <- git "log" ["--format=%H",range]
        let hashes = words range
        withLogs <- filterM (doesFileExist . logsOf) hashes
        need (map summaryOf withLogs)

        Stdout json <- self "IndexReport" withLogs
        writeFile' out json
    want ["site/out/all-summaries.json"]

    "site/out/settings.json" *> \out -> do
        need ["settings.yaml"]

        Stdout json <- self "JsonSettings" []
        writeFile' out json
    want ["site/out/settings.json"]

    phony "clean" $ do
        removeFilesAfter "site/out" ["//*"]