{-# OPTIONS_GHC -fno-warn-type-defaults #-}
{-# LANGUAGE RecordWildCards #-}

import Data.Foldable     (for_)
import Test.Hspec        (Spec, describe, it, shouldBe)
import Test.Hspec.Runner (configFastFail, defaultConfig, hspecWith)

import Sieve (primesUpTo)

main :: IO ()
main = hspecWith defaultConfig {configFastFail = True} specs

specs :: Spec
specs = describe "sieve" $
          describe "primesUpTo" $ for_ cases test
  where

    test Case{..} = it description assertion
      where
        assertion = primesUpTo (fromIntegral limit)
                    `shouldBe`
                    fromIntegral <$> expected

-- Test cases adapted from `exercism/x-common` on 2016-09-12.

data Case = Case { description ::  String
                 , limit       ::  Integer
                 , expected    :: [Integer]
                 }

cases :: [Case]
cases = [ Case { description = "no primes under two"
               , limit       =  1
               , expected    = []
               }
        , Case { description = "find first prime"
               , limit       = 2
               , expected    = [2]
               }
        , Case { description = "find primes up to 10"
               , limit       = 10
               , expected    = [2, 3, 5, 7]
               }
        , Case { description = "limit is prime"
               , limit       = 13
               , expected    = [2, 3, 5, 7, 11, 13]
               }
        , Case { description = "find primes up to 1000"
               , limit       = 1000
               , expected    = [ 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37
                               , 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83
                               , 89, 97, 101, 103, 107, 109, 113, 127, 131
                               , 137, 139, 149, 151, 157, 163, 167, 173, 179
                               , 181, 191, 193, 197, 199, 211, 223, 227, 229
                               , 233, 239, 241, 251, 257, 263, 269, 271, 277
                               , 281, 283, 293, 307, 311, 313, 317, 331, 337
                               , 347, 349, 353, 359, 367, 373, 379, 383, 389
                               , 397, 401, 409, 419, 421, 431, 433, 439, 443
                               , 449, 457, 461, 463, 467, 479, 487, 491, 499
                               , 503, 509, 521, 523, 541, 547, 557, 563, 569
                               , 571, 577, 587, 593, 599, 601, 607, 613, 617
                               , 619, 631, 641, 643, 647, 653, 659, 661, 673
                               , 677, 683, 691, 701, 709, 719, 727, 733, 739
                               , 743, 751, 757, 761, 769, 773, 787, 797, 809
                               , 811, 821, 823, 827, 829, 839, 853, 857, 859
                               , 863, 877, 881, 883, 887, 907, 911, 919, 929
                               , 937, 941, 947, 953, 967, 971, 977, 983, 991
                               , 997 ]
               }
        ]
