{-# OPTIONS_GHC -fno-warn-deprecations #-}
{-# LANGUAGE CPP #-}
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE ScopedTypeVariables #-}

-- |
-- Stability: provisional
module Test.Hspec.Core.Runner (
-- * Simple interface
  hspec
, hspecWith
, hspecResult
, hspecWithResult

-- ** Summary
, Summary (..)
, isSuccess
, evaluateSummary

-- * Running a spec
{- |
To run a spec `hspec` performs a sequence of steps:

1. Evaluate a `Spec` to a forest of `SpecTree`s
1. Read config values from the command-line, config files and the process environment
1. Execute each spec item of the forest and report results to `stdout`
1. Exit with `exitFailure` if at least on spec item fails

The four primitives `evalSpec`, `readConfig`, `runSpecForest` and
`evaluateResult` each perform one of these steps respectively.

`hspec` is defined in terms of these primitives. Loosely speaking, a definition
for @hspec@ is:

@
hspec = `evalSpec` `defaultConfig` >=> \\ (config, spec) ->
      `getArgs`
  >>= `readConfig` config
  >>= `withArgs` [] . `runSpecForest` spec
  >>= `evaluateResult`
@

Loosely speaking in the sense that this definition of @hspec@ ignores
@--rerun-all-on-success@.

Using these primitives individually gives you more control over how a spec is
run.  However, if you need support for @--rerun-all-on-success@ then you should
try hard to solve your use case with one of `hspec`, `hspecWith`, `hspecResult`
or `hspecWithResult`.

-}
, evalSpec
, runSpecForest
, evaluateResult

-- ** Result

-- *** Spec Result
, Test.Hspec.Core.Runner.Result.SpecResult
, Test.Hspec.Core.Runner.Result.specResultItems
, Test.Hspec.Core.Runner.Result.specResultSuccess
, toSummary

-- *** Result Item
, Test.Hspec.Core.Runner.Result.ResultItem
, Test.Hspec.Core.Runner.Result.resultItemPath
, Test.Hspec.Core.Runner.Result.resultItemStatus
, Test.Hspec.Core.Runner.Result.resultItemIsFailure

-- *** Result Item Status
, Test.Hspec.Core.Runner.Result.ResultItemStatus(..)

-- * Config
, Config (..)
, ColorMode (..)
, UnicodeMode(..)
, Path
, defaultConfig
, registerFormatter
, registerDefaultFormatter
, configAddFilter
, readConfig

-- * Legacy
, runSpec

-- * Re-exports
, Spec
, SpecWith

#ifdef TEST
, UseColor(..)
, ProgressReporting(..)
, rerunAll
, specToEvalForest
, colorOutputSupported
, unicodeOutputSupported
#endif
) where

import           Prelude ()
import           Test.Hspec.Core.Compat hiding (unicodeOutputSupported)
import qualified Test.Hspec.Core.Compat as Compat

import           Data.List.NonEmpty (nonEmpty)
import           System.IO
import           System.Environment (getArgs, withArgs)
import           System.Exit (exitFailure)
import           System.Random
import           Control.Monad.ST
import           Data.STRef

import           System.Console.ANSI (hSupportsANSI, hHideCursor, hShowCursor)
import qualified Test.QuickCheck as QC

import           Test.Hspec.Core.Util (Path)
import           Test.Hspec.Core.Clock
import           Test.Hspec.Core.Spec hiding (pruneTree, pruneForest)
import           Test.Hspec.Core.Tree (formatDefaultDescription)
import           Test.Hspec.Core.Config
import           Test.Hspec.Core.Config.Definition as Config (getSeed)

#ifdef ENABLE_LEGACY_V1_FORMATTERS
import           Test.Hspec.Core.Config.Definition as Config (getFormatter)
#endif

import           Test.Hspec.Core.Extension.Config.Type as Extension (applySpecTransformation)
import           Test.Hspec.Core.Format (Format, FormatConfig(..))
import qualified Test.Hspec.Core.Formatters.V2 as V2
import           Test.Hspec.Core.FailureReport
import           Test.Hspec.Core.QuickCheck.Util
import           Test.Hspec.Core.Shuffle

import           Test.Hspec.Core.Runner.PrintSlowSpecItems
import           Test.Hspec.Core.Runner.Eval hiding (ColorMode(..), Tree(..))
import qualified Test.Hspec.Core.Runner.Eval as Eval
import           Test.Hspec.Core.Runner.Result

-- |
-- Make a formatter available for use with @--format@.
--
-- @since 2.10.5
registerFormatter :: (String, FormatConfig -> IO Format) -> Config -> Config
{-# DEPRECATED registerFormatter "Use [@registerFormatter@](https://hackage.haskell.org/package/hspec-api/docs/Test-Hspec-Api-Format-V2.html#v:registerFormatter) instead." #-}
registerFormatter formatter config = config { configAvailableFormatters = formatter : configAvailableFormatters config }

-- |
-- Make a formatter available for use with @--format@ and use it by default.
--
-- @since 2.10.5
registerDefaultFormatter :: (String, FormatConfig -> IO Format) -> Config -> Config
{-# DEPRECATED registerDefaultFormatter "Use [@useFormatter@](https://hackage.haskell.org/package/hspec-api/docs/Test-Hspec-Api-Format-V2.html#v:useFormatter) instead." #-}
registerDefaultFormatter formatter@(_, format) config = (registerFormatter formatter config) { configFormat = Just format }

applyFilterPredicates :: Config -> [Tree c EvalItem] -> [Tree c EvalItem]
applyFilterPredicates c = filterForestWithLabels p
  where
    include :: Path -> Bool
    include = fromMaybe (const True) (configFilterPredicate c)

    skip :: Path -> Bool
    skip = fromMaybe (const False) (configSkipPredicate c)

    p :: [String] -> EvalItem -> Bool
    p groups item = include path && not (skip path)
      where
        path = (groups, evalItemDescription item)

applyDryRun :: Config -> [EvalItemTree] -> [EvalItemTree]
applyDryRun c
  | configDryRun c = bimapForest removeCleanup markSuccess
  | otherwise = id
  where
    removeCleanup :: IO () -> IO ()
    removeCleanup _ = pass

    markSuccess :: EvalItem -> EvalItem
    markSuccess item = item {evalItemAction = \ _ -> return (0, Result "" Success)}

-- | Run a given spec and write a report to `stdout`.
-- Exit with `exitFailure` if at least one spec item fails.
--
-- /Note/: `hspec` handles command-line options and reads config files.  This
-- is not always desirable.  Use `evalSpec` and `runSpecForest` if you need
-- more control over these aspects.
hspec :: Spec -> IO ()
hspec = hspecWith defaultConfig

-- |
-- Evaluate a `Spec` to a forest of `SpecTree`s.  This does not execute any
-- spec items, but it does run any IO that is used during spec construction
-- time (see `runIO`).
--
-- A `Spec` may modify a `Config` through `modifyConfig`.  These modifications
-- are applied to the given config (the first argument).
--
-- @since 2.10.0
evalSpec :: Config -> SpecWith a -> IO (Config, [SpecTree a])
evalSpec config spec = do
  (Endo f, forest) <- runSpecM spec
  return (f config, forest)

-- Add a seed to given config if there is none.  That way the same seed is used
-- for all properties.  This helps with --seed and --rerun.
ensureSeed :: Config -> IO (Config, Integer)
ensureSeed config = do
  seed <- case Config.getSeed config of
    Nothing -> toInteger <$> newSeed
    Just seed -> return seed
  return (config { configSeed = Just seed }, seed)

-- | Run given spec with custom options.
-- This is similar to `hspec`, but more flexible.
hspecWith :: Config -> Spec -> IO ()
hspecWith defaults = hspecWithSpecResult defaults >=> evaluateResult

-- | Exit with `exitFailure` if the given `Summary` indicates that there was at
-- least one failure.
evaluateSummary :: Summary -> IO ()
evaluateSummary summary = unless (isSuccess summary) exitFailure

evaluateResult :: SpecResult -> IO ()
evaluateResult result = unless (specResultSuccess result) exitFailure

-- | Run given spec and returns a summary of the test run.
--
-- /Note/: `hspecResult` does not exit with `exitFailure` on failing spec
-- items.  If you need this, you have to check the `Summary` yourself and act
-- accordingly.
hspecResult :: Spec -> IO Summary
hspecResult = hspecWithResult defaultConfig

-- | Run given spec with custom options and returns a summary of the test run.
--
-- /Note/: `hspecWithResult` does not exit with `exitFailure` on failing spec
-- items.  If you need this, you have to check the `Summary` yourself and act
-- accordingly.
hspecWithResult :: Config -> Spec -> IO Summary
hspecWithResult config = fmap toSummary . hspecWithSpecResult config

hspecWithSpecResult :: Config -> Spec -> IO SpecResult
hspecWithSpecResult defaults spec = do
  (c, forest) <- evalSpec defaults spec
  config <- getArgs >>= readConfig c
  oldFailureReport <- readFailureReportOnRerun config

  let
    normalMode :: IO SpecResult
    normalMode = doNotLeakCommandLineArgumentsToExamples $ runSpecForest_ oldFailureReport forest config

    rerunAllMode :: IO SpecResult
    rerunAllMode = do
      result <- normalMode
      if rerunAll config oldFailureReport result then
        hspecWithSpecResult defaults spec
      else
        return result

  -- With --rerun-all we may run the spec twice. For that reason GHC can not
  -- optimize away the spec tree. That means that the whole spec tree has to
  -- be constructed in memory and we loose constant space behavior.
  --
  -- By separating between rerunAllMode and normalMode here, we retain
  -- constant space behavior in normalMode.
  --
  -- see: https://github.com/hspec/hspec/issues/169
  if configRerunAllOnSuccess config then do
    rerunAllMode
  else do
    normalMode

-- |
-- /Note/: `runSpec` is deprecated. It ignores any modifications applied
-- through `modifyConfig`.  Use `evalSpec` and `runSpecForest` instead.
runSpec :: Spec -> Config -> IO Summary
runSpec spec config = evalSpec defaultConfig spec >>= fmap toSummary . flip runSpecForest config . snd

-- |
-- `runSpecForest` is the most basic primitive to run a spec. `hspec` is
-- defined in terms of @runSpecForest@:
--
-- @
-- hspec = `evalSpec` `defaultConfig` >=> \\ (config, spec) ->
--       `getArgs`
--   >>= `readConfig` config
--   >>= `withArgs` [] . runSpecForest spec
--   >>= `evaluateResult`
-- @
--
-- @since 2.10.0
runSpecForest :: [SpecTree ()] -> Config -> IO SpecResult
runSpecForest spec config = do
  oldFailureReport <- readFailureReportOnRerun config
  runSpecForest_ oldFailureReport spec config

mapItem :: (Item a -> Item b) -> [SpecTree a] -> [SpecTree b]
mapItem f = map (fmap f)

mapItemIf :: (Item a -> Bool) -> (Item a -> Item a) -> [SpecTree a] -> [SpecTree a]
mapItemIf p f = mapItem $ \ item -> if p item then f item else item

addDefaultDescriptions :: [SpecTree a] -> [SpecTree a]
addDefaultDescriptions = mapItem addDefaultDescription
  where
    addDefaultDescription :: Item a -> Item a
    addDefaultDescription item
      | null (itemRequirement item) = item { itemRequirement = defaultRequirement }
      | otherwise = item
      where
        defaultRequirement = maybe "(unspecified behavior)" formatDefaultDescription (itemLocation item)

failItemsWithEmptyDescription :: Config -> [SpecTree a] -> [SpecTree a]
failItemsWithEmptyDescription config
  | configFailOnEmptyDescription config = mapItemIf condition (failWith failure)
  | otherwise = id
  where
    condition = null . itemRequirement
    failure = "item has no description; failing due to --fail-on=empty-description"

failFocusedItems :: Config -> [SpecTree a] -> [SpecTree a]
failFocusedItems config
  | configFailOnFocused config = mapItemIf condition (failWith failure)
  | otherwise = id
  where
    condition = itemIsFocused
    failure = "item is focused; failing due to --fail-on=focused"

failWith :: forall a. String -> Item a -> Item a
failWith reason item = item {itemExample = example}
  where
    failure :: ResultStatus
    failure = Failure Nothing (Reason reason)

    example :: Params -> (ActionWith a -> IO ()) -> ProgressCallback -> IO Result
    example params hook p = do
      Result info status <- itemExample item params hook p
      return $ Result info $ case status of
        Success -> failure
        Pending _ _ -> failure
        Failure{} -> status

failPendingItems :: Config -> [SpecTree a] -> [SpecTree a]
failPendingItems config
  | configFailOnPending config = mapItem failPending
  | otherwise = id

failPending :: forall a. Item a -> Item a
failPending item = item {itemExample = example}
  where
    example :: Params -> (ActionWith a -> IO ()) -> ProgressCallback -> IO Result
    example params hook p = do
      Result info status <- itemExample item params hook p
      return $ Result info $ case status of
        Pending loc _ -> Failure loc (Reason "item is pending; failing due to --fail-on=pending")
        _ -> status

focusSpec :: Config -> [SpecTree a] -> [SpecTree a]
focusSpec config spec
  | configFocusedOnly config = spec
  | otherwise = focusForest spec

runSpecForest_ :: Maybe FailureReport -> [SpecTree ()] -> Config -> IO SpecResult
runSpecForest_ oldFailureReport spec c_ = do

  (config, seed) <- ensureSeed (applyFailureReport oldFailureReport c_)

  colorMode <- colorOutputSupported (configColorMode config) (hSupportsANSI stdout)
  outputUnicode <- unicodeOutputSupported (configUnicodeMode config) stdout

  let
    filteredSpec = specToEvalForest seed config spec
    qcArgs = configQuickCheckArgs config
    !numberOfItems = countEvalItems filteredSpec

  when (configFailOnEmpty config && numberOfItems == 0) $ do
    when (countSpecItems spec /= 0) $ do
      die "all spec items have been filtered; failing due to --fail-on=empty"

  concurrentJobs <- maybe getDefaultConcurrentJobs return $ configConcurrentJobs config

  results <- fmap toSpecResult . withHiddenCursor (progressReporting colorMode) stdout $ do
    let
      formatConfig = FormatConfig {
        formatConfigUseColor = shouldUseColor colorMode
      , formatConfigReportProgress = progressReporting colorMode == ProgressReportingEnabled
      , formatConfigOutputUnicode = outputUnicode
      , formatConfigUseDiff = configDiff config
      , formatConfigDiffContext = configDiffContext config
      , formatConfigExternalDiff = if configDiff config then ($ configDiffContext config) <$> configExternalDiff config else Nothing
      , formatConfigPrettyPrint = configPrettyPrint config
      , formatConfigPrettyPrintFunction = if configPrettyPrint config then Just (configPrettyPrintFunction config outputUnicode) else Nothing
      , formatConfigFormatException = configFormatException config
      , formatConfigPrintTimes = configTimes config
      , formatConfigHtmlOutput = configHtmlOutput config
      , formatConfigPrintCpuTime = configPrintCpuTime config
      , formatConfigUsedSeed = seed
      , formatConfigExpectedTotalCount = numberOfItems
      , formatConfigExpertMode = configExpertMode config
      }

      formatter :: FormatConfig -> IO Format
#ifdef ENABLE_LEGACY_V1_FORMATTERS
      formatter = fromMaybe (V2.formatterToFormat V2.checks) (Config.getFormatter config)
#else
      formatter = V2.formatterToFormat V2.checks
#endif

    format <- maybe id printSlowSpecItems (configPrintSlowItems config) <$> formatter formatConfig

    let
      evalConfig = EvalConfig {
        evalConfigFormat = format
      , evalConfigConcurrentJobs = concurrentJobs
      , evalConfigFailFast = configFailFast config
      , evalConfigColorMode = bool Eval.ColorDisabled Eval.ColorEnabled (shouldUseColor colorMode)
      }
    runFormatter evalConfig filteredSpec

  let
    failures :: [Path]
    failures = map resultItemPath $ filter resultItemIsFailure $ specResultItems results

  dumpFailureReport config seed qcArgs failures

  return results

specToEvalForest :: Integer -> Config -> [SpecTree ()] -> [EvalTree]
specToEvalForest seed config =
      failItemsWithEmptyDescription config
  >>> addDefaultDescriptions
  >>> failFocusedItems config
  >>> failPendingItems config
  >>> Extension.applySpecTransformation config
  >>> focusSpec config
  >>> toEvalItemForest params
  >>> applyDryRun config
  >>> applyFilterPredicates config
  >>> randomize
  >>> pruneForest
  where
    params :: Params
    params = Params (configQuickCheckArgs config) (configSmallCheckDepth config)

    randomize :: [Tree c a] -> [Tree c a]
    randomize
      | configRandomize config = randomizeForest seed
      | otherwise = id

pruneForest :: [Tree c a] -> [Eval.Tree c a]
pruneForest = mapMaybe pruneTree

pruneTree :: Tree c a -> Maybe (Eval.Tree c a)
pruneTree node = case node of
  Node group xs -> Eval.Node group <$> prune xs
  NodeWithCleanup loc action xs -> Eval.NodeWithCleanup loc action <$> prune xs
  Leaf item -> Just (Eval.Leaf item)
  where
    prune = nonEmpty . pruneForest

type EvalItemTree = Tree (IO ()) EvalItem

toEvalItemForest :: Params -> [SpecTree ()] -> [EvalItemTree]
toEvalItemForest params = bimapForest id toEvalItem . filterForest itemIsFocused
  where
    toEvalItem :: Item () -> EvalItem
    toEvalItem (Item requirement loc isParallelizable _isFocused _annotations e) = EvalItem {
      evalItemDescription = requirement
    , evalItemLocation = loc
    , evalItemConcurrency = if isParallelizable == Just True then Concurrent else Sequential
    , evalItemAction = \ progress -> measure $ e params withUnit progress
    }

    withUnit :: ActionWith () -> IO ()
    withUnit action = action ()

dumpFailureReport :: Config -> Integer -> QC.Args -> [Path] -> IO ()
dumpFailureReport config seed qcArgs xs = do
  writeFailureReport config FailureReport {
      failureReportSeed = seed
    , failureReportMaxSuccess = QC.maxSuccess qcArgs
    , failureReportMaxSize = QC.maxSize qcArgs
    , failureReportMaxDiscardRatio = QC.maxDiscardRatio qcArgs
    , failureReportPaths = xs
    }

doNotLeakCommandLineArgumentsToExamples :: IO a -> IO a
doNotLeakCommandLineArgumentsToExamples = withArgs []

withHiddenCursor :: ProgressReporting -> Handle -> IO a -> IO a
withHiddenCursor progress h = case progress of
  ProgressReportingDisabled -> id
  ProgressReportingEnabled -> bracket_ (hHideCursor h) (hShowCursor h)

data UseColor = ColorDisabled | ColorEnabled ProgressReporting
  deriving (Eq, Show)

data ProgressReporting = ProgressReportingDisabled | ProgressReportingEnabled
  deriving (Eq, Show)

shouldUseColor :: UseColor -> Bool
shouldUseColor c = case c of
  ColorDisabled -> False
  ColorEnabled _ -> True

progressReporting :: UseColor -> ProgressReporting
progressReporting c = case c of
  ColorDisabled -> ProgressReportingDisabled
  ColorEnabled r -> r

colorOutputSupported :: ColorMode -> IO Bool -> IO UseColor
colorOutputSupported mode isTerminalDevice = do
  github <- githubActions
  buildkite <- lookupEnv "BUILDKITE" <&> (== Just "true")
  let
    progress :: ProgressReporting
    progress
      | github || buildkite = ProgressReportingDisabled
      | otherwise = ProgressReportingEnabled

    colorEnabled :: UseColor
    colorEnabled = ColorEnabled progress
  case mode of
    ColorAuto -> bool ColorDisabled colorEnabled . (github ||) <$> colorTerminal
    ColorNever -> return ColorDisabled
    ColorAlways -> return colorEnabled
  where
    githubActions :: IO Bool
    githubActions = lookupEnv "GITHUB_ACTIONS" <&> (== Just "true")

    colorTerminal :: IO Bool
    colorTerminal = (&&) <$> (not <$> noColor) <*> isTerminalDevice

    noColor :: IO Bool
    noColor = lookupEnv "NO_COLOR" <&> (/= Nothing)

unicodeOutputSupported :: UnicodeMode -> Handle -> IO Bool
unicodeOutputSupported mode h = case mode of
  UnicodeAuto -> Compat.unicodeOutputSupported h
  UnicodeNever -> return False
  UnicodeAlways -> return True

rerunAll :: Config -> Maybe FailureReport -> SpecResult -> Bool
rerunAll config mOldFailureReport result = case mOldFailureReport of
  Nothing -> False
  Just oldFailureReport ->
       configRerunAllOnSuccess config
    && configRerun config
    && specResultSuccess result
    && (not . null) (failureReportPaths oldFailureReport)

randomizeForest :: Integer -> [Tree c a] -> [Tree c a]
randomizeForest seed t = runST $ do
  ref <- newSTRef (mkStdGen $ fromIntegral seed)
  shuffleForest ref t

countEvalItems :: [Eval.Tree c a] -> Int
countEvalItems = getSum . foldMap (foldMap . const $ Sum 1)

countSpecItems :: [Tree c a] -> Int
countSpecItems = getSum . foldMap (foldMap . const $ Sum 1)
