{-# OPTIONS_GHC -fno-warn-incomplete-uni-patterns #-}
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE MagicHash #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE UnboxedTuples #-}

module Main where

import qualified Crypto.Cipher.ChaCha20 as ChaCha
import qualified Data.ByteString as BS
import qualified Data.ByteString.Base16 as B16
import Data.Foldable (for_)
import Data.Maybe (fromJust)
import qualified Data.Primitive.PrimArray as PA
import Data.Word (Word32)
import Test.Tasty
import qualified Test.Tasty.HUnit as H

main :: IO ()
main = defaultMain $ testGroup "ppad-chacha" [
    quarter
  , quarter_fullstate
  , chacha20_block_init
  , chacha20_rounds
  , encrypt
  , crypt1
  , crypt2
  , crypt3
  ]

quarter :: TestTree
quarter = H.testCase "quarter round" $ do
  let e = (0xea2a92f4, 0xcb1cf8ce, 0x4581472e, 0x5881c4bb)
      o = ChaCha._quarter_pure 0x11111111 0x01020304 0x9b8d6f43 0x01234567
  H.assertEqual mempty e o

quarter_fullstate :: TestTree
quarter_fullstate = H.testCase "quarter round (full chacha state)" $ do
  let inp :: PA.PrimArray Word32
      inp = PA.primArrayFromList [
          0x879531e0, 0xc5ecf37d, 0x516461b1, 0xc9a62f8a
        , 0x44c20ef3, 0x3390af7f, 0xd9fc690b, 0x2a5f714c
        , 0x53372767, 0xb00a5631, 0x974c541a, 0x359e9963
        , 0x5c971061, 0x3d631689, 0x2098d9d6, 0x91dbd320
        ]
  hot <- PA.unsafeThawPrimArray inp

  ChaCha._quarter (ChaCha.ChaCha hot) 2 7 8 13

  o <- PA.unsafeFreezePrimArray hot

  let e :: PA.PrimArray Word32
      e = PA.primArrayFromList [
          0x879531e0, 0xc5ecf37d, 0xbdb886dc, 0xc9a62f8a
        , 0x44c20ef3, 0x3390af7f, 0xd9fc690b, 0xcfacafd2
        , 0xe46bea80, 0xb00a5631, 0x974c541a, 0x359e9963
        , 0x5c971061, 0xccc07c79, 0x2098d9d6, 0x91dbd320
        ]

  H.assertEqual mempty e o

block_key :: BS.ByteString
block_key = fromJust $
  B16.decode "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f"

block_non :: BS.ByteString
block_non = fromJust $ B16.decode "000000090000004a00000000"

chacha20_block_init :: TestTree
chacha20_block_init = H.testCase "chacha20 state init" $ do
  let key = ChaCha._parse_key block_key
      non = ChaCha._parse_nonce block_non
  ChaCha.ChaCha foo <- ChaCha._chacha key 1 non
  state <- PA.freezePrimArray foo 0 16
  let ref = PA.primArrayFromList [
          0x61707865, 0x3320646e, 0x79622d32, 0x6b206574
        , 0x03020100, 0x07060504, 0x0b0a0908, 0x0f0e0d0c
        , 0x13121110, 0x17161514, 0x1b1a1918, 0x1f1e1d1c
        , 0x00000001, 0x09000000, 0x4a000000, 0x00000000
        ]
  H.assertEqual mempty ref state

chacha20_rounds :: TestTree
chacha20_rounds = H.testCase "chacha20 20 rounds" $ do
  let key = ChaCha._parse_key block_key
      non = ChaCha._parse_nonce block_non
  state@(ChaCha.ChaCha s) <- ChaCha._chacha key 1 non
  for_ [1..10 :: Int] (const (ChaCha._rounds state))

  out <- PA.freezePrimArray s 0 16

  let ref = PA.primArrayFromList [
          0x837778ab, 0xe238d763, 0xa67ae21e, 0x5950bb2f
        , 0xc4f2d0c7, 0xfc62bb2f, 0x8fa018fc, 0x3f5ec7b7
        , 0x335271c2, 0xf29489f3, 0xeabda8fc, 0x82e46ebd
        , 0xd19c12b4, 0xb04e16de, 0x9e83d0cb, 0x4e3c50a2
        ]

  H.assertEqual mempty ref out

crypt_plain :: BS.ByteString
crypt_plain = case B16.decode "4c616469657320616e642047656e746c656d656e206f662074686520636c617373206f66202739393a204966204920636f756c64206f6666657220796f75206f6e6c79206f6e652074697020666f7220746865206675747572652c2073756e73637265656e20776f756c642062652069742e" of
  Nothing -> error "bang"
  Just x -> x

crypt_cip :: BS.ByteString
crypt_cip = case B16.decode "6e2e359a2568f98041ba0728dd0d6981e97e7aec1d4360c20a27afccfd9fae0bf91b65c5524733ab8f593dabcd62b3571639d624e65152ab8f530c359f0861d807ca0dbf500d6a6156a38e088a22b65e52bc514d16ccf806818ce91ab77937365af90bbf74a35be6b40b8eedf2785e42874d" of
  Nothing -> error "bang"
  Just x -> x

crypt_non :: BS.ByteString
crypt_non = case B16.decode "000000000000004a00000000" of
  Nothing -> error "bang"
  Just x -> x

encrypt :: TestTree
encrypt = H.testCase "chacha20 encrypt" $ do
  let Right o = ChaCha.cipher block_key 1 crypt_non crypt_plain
  H.assertEqual mempty crypt_cip o

-- additional vectors

crypt1 :: TestTree
crypt1 = H.testCase "chacha20 encrypt (A.2 #1)" $ do
  let key = fromJust . B16.decode $
        "0000000000000000000000000000000000000000000000000000000000000000"
      non = fromJust . B16.decode $
        "000000000000000000000000"
      con = 0
      plain = fromJust . B16.decode $
        "00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
      cip = fromJust . B16.decode $
        "76b8e0ada0f13d90405d6ae55386bd28bdd219b8a08ded1aa836efcc8b770dc7da41597c5157488d7724e03fb8d84a376a43b8f41518a11cc387b669b2ee6586"
      Right out = ChaCha.cipher key con non plain
  H.assertEqual mempty cip out

crypt2 :: TestTree
crypt2 = H.testCase "chacha20 encrypt (A.2 #2)" $ do
  let key = fromJust . B16.decode $
        "0000000000000000000000000000000000000000000000000000000000000001"
      non = fromJust . B16.decode $
        "000000000000000000000002"
      con = 1
      plain = fromJust . B16.decode $
        "416e79207375626d697373696f6e20746f20746865204945544620696e74656e6465642062792074686520436f6e7472696275746f7220666f72207075626c69636174696f6e20617320616c6c206f722070617274206f6620616e204945544620496e7465726e65742d4472616674206f722052464320616e6420616e792073746174656d656e74206d6164652077697468696e2074686520636f6e74657874206f6620616e204945544620616374697669747920697320636f6e7369646572656420616e20224945544620436f6e747269627574696f6e222e20537563682073746174656d656e747320696e636c756465206f72616c2073746174656d656e747320696e20494554462073657373696f6e732c2061732077656c6c206173207772697474656e20616e6420656c656374726f6e696320636f6d6d756e69636174696f6e73206d61646520617420616e792074696d65206f7220706c6163652c207768696368206172652061646472657373656420746f"
      cip = fromJust . B16.decode $
        "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"
      Right out = ChaCha.cipher key con non plain
  H.assertEqual mempty cip out

crypt3 :: TestTree
crypt3 = H.testCase "chacha20 encrypt (A.2 #3)" $ do
  let key = fromJust . B16.decode $
        "1c9240a5eb55d38af333888604f6b5f0473917c1402b80099dca5cbc207075c0"
      non = fromJust . B16.decode $
        "000000000000000000000002"
      con = 42
      plain = fromJust . B16.decode $
        "2754776173206272696c6c69672c20616e642074686520736c6974687920746f7665730a446964206779726520616e642067696d626c6520696e2074686520776162653a0a416c6c206d696d737920776572652074686520626f726f676f7665732c0a416e6420746865206d6f6d65207261746873206f757467726162652e"
      cip = fromJust . B16.decode $
        "62e6347f95ed87a45ffae7426f27a1df5fb69110044c0d73118effa95b01e5cf166d3df2d721caf9b21e5fb14c616871fd84c54f9d65b283196c7fe4f60553ebf39c6402c42234e32a356b3e764312a61a5532055716ead6962568f87d3f3f7704c6a8d1bcd1bf4d50d6154b6da731b187b58dfd728afa36757a797ac188d1"
      Right out = ChaCha.cipher key con non plain
  H.assertEqual mempty cip out