module Main where

import Control.Exception (evaluate)
import Control.Monad (unless)
import qualified Data.Text.IO as Text
import qualified Debug.TimeStats as TimeStats
import qualified Debug.TimeStats.Internal as Internal
import System.Environment (setEnv)
import System.Exit (exitFailure)

fib :: Int -> Int
fib n = if n < 2 then 1 else fib (n - 1) + fib (n - 2)

main :: IO ()
main = do
    testMeasureM
    testFormatNatWithSeparator

testMeasureM :: IO ()
testMeasureM = do
    setEnv "DEBUG_TIMESTATS_ENABLE" "1"
    _ <- TimeStats.measureM "fib" $ evaluate (fib 21)
    _ <- TimeStats.measureM "fib2" $ evaluate (fib 20)
    _ <- TimeStats.measureM "fib2" $ evaluate (fib 19)
    xs <- TimeStats.collect
    let expected =
          [ ("fib", TimeStats.TimeStats 0 1)
          , ("fib2", TimeStats.TimeStats 0 2)
          ]
    unless (eqStats xs expected) $ do
      putStrLn "unexpected timestats:"
      Text.putStrLn (TimeStats.asText xs)
      exitFailure
  where
    eqStats xs ys = length xs == length ys && and (zipWith eqStat xs ys)
    eqStat (lbl0, ts0) (lbl1, ts1) =
      lbl0 == lbl1 && TimeStats.countStat ts0 == TimeStats.countStat ts1

testFormatNatWithSeparator :: IO ()
testFormatNatWithSeparator = do
    testCase   123456789   "123_456_789"
    testCase    23456789    "23_456_789"
    testCase     3456789     "3_456_789"
    testCase      456789       "456_789"
    testCase       56789        "56_789"
    testCase        6789         "6_789"
    testCase         789           "789"
    testCase          89            "89"
    testCase           9             "9"
    testCase           0             "0"
    testCase (-123456789) "-123_456_789"
    testCase  (-23456789)  "-23_456_789"
    testCase   (-3456789)   "-3_456_789"
    testCase    (-456789)     "-456_789"
    testCase     (-56789)      "-56_789"
    testCase      (-6789)       "-6_789"
    testCase       (-789)         "-789"
    testCase        (-89)          "-89"
    testCase         (-9)           "-9"
  where
    testCase i expected = do
      let actual = Internal.formatIntWithSeparator '_' i  "a"
      unless (actual == expected ++ "a") $ do
        putStrLn $ "unexpected output of formatIntWithSeparator:"
        putStrLn $ "expected: " ++ show (expected ++ "a")
        putStrLn $ "  actual: " ++ show actual
        exitFailure