import Codec.Compression.Zlib.Deflate
import Test.Framework
import Test.Framework.Providers.HUnit
import Test.HUnit(assertEqual)

rfcSimpleTestLengths :: [(Char, Int)]
rfcSimpleTestLengths = [
    ('A', 3)
  , ('B', 3)
  , ('C', 3)
  , ('D', 3)
  , ('E', 3)
  , ('F', 2)
  , ('G', 4)
  , ('H', 4)
  ]

rfcSimpleTestResults :: [(Char, Int, Int)]
rfcSimpleTestResults = [
    ('A', 3, 2)  --  010
  , ('B', 3, 3)  --  011
  , ('C', 3, 4)  --  100
  , ('D', 3, 5)  --  101
  , ('E', 3, 6)  --  110
  , ('F', 2, 0)  --   00
  , ('G', 4, 14) -- 1110
  , ('H', 4, 15) -- 1111
  ]

fixedHuffmanLengths :: [(Int, Int)]
fixedHuffmanLengths =
  ([(x, 8) | x <- [0   .. 143]] ++
   [(x, 9) | x <- [144 .. 255]] ++
   [(x, 7) | x <- [256 .. 279]] ++
   [(x, 8) | x <- [280 .. 287]])

fixedHuffmanResults :: [(Int, Int, Int)]
fixedHuffmanResults =
  ([(fst x, 8, snd x) | x <- zip [0  ..143] [48 ..191]] ++ --  00110000 through  10111111
   [(fst x, 9, snd x) | x <- zip [144..255] [400..511]] ++ -- 110010000 through 111111111
   [(fst x, 7, snd x) | x <- zip [256..279] [0  .. 23]] ++ --   0000000 through   0010111
   [(fst x, 8, snd x) | x <- zip [280..287] [192..199]])   --  11000000 through  11000111

zlibTests :: Test
zlibTests =
  testGroup "DEFLATE / ZLib Algorithm Testing" [
    testCase "RFC 1951 Code Generation Test"
      (assertEqual "" (computeCodeValues rfcSimpleTestLengths)
                      rfcSimpleTestResults)
  , testCase "Fixed Huffman lengths make right tree"
      (assertEqual "" (computeCodeValues fixedHuffmanLengths)
                      fixedHuffmanResults)
  ]

main :: IO ()
main = defaultMain [zlibTests]