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-rw-r--r--users/wpcarro/assessments/brilliant/.ghci2
-rw-r--r--users/wpcarro/assessments/brilliant/App.hs41
-rw-r--r--users/wpcarro/assessments/brilliant/Keyboard.hs58
-rw-r--r--users/wpcarro/assessments/brilliant/Main.hs43
-rw-r--r--users/wpcarro/assessments/brilliant/README.md82
-rw-r--r--users/wpcarro/assessments/brilliant/Spec.hs103
-rw-r--r--users/wpcarro/assessments/brilliant/Transforms.hs52
-rw-r--r--users/wpcarro/assessments/brilliant/Utils.hs13
-rw-r--r--users/wpcarro/assessments/brilliant/default.nix16
-rw-r--r--users/wpcarro/assessments/brilliant/shell.nix16
10 files changed, 426 insertions, 0 deletions
diff --git a/users/wpcarro/assessments/brilliant/.ghci b/users/wpcarro/assessments/brilliant/.ghci
new file mode 100644
index 000000000000..efc88e630ccb
--- /dev/null
+++ b/users/wpcarro/assessments/brilliant/.ghci
@@ -0,0 +1,2 @@
+:set prompt "> "
+:set -Wall
diff --git a/users/wpcarro/assessments/brilliant/App.hs b/users/wpcarro/assessments/brilliant/App.hs
new file mode 100644
index 000000000000..0272988f371c
--- /dev/null
+++ b/users/wpcarro/assessments/brilliant/App.hs
@@ -0,0 +1,41 @@
+--------------------------------------------------------------------------------
+module App where
+--------------------------------------------------------------------------------
+import Keyboard (Keyboard(..))
+import Transforms (Transform(..))
+import Utils ((|>))
+
+import qualified Data.Char as Char
+import qualified Utils
+import qualified Data.List.Split as Split
+import qualified Keyboard
+import qualified Data.HashMap.Strict as HM
+--------------------------------------------------------------------------------
+
+transform :: Keyboard -> Transform -> Keyboard
+
+transform (Keyboard xs) xform =
+  case xform of
+    HorizontalFlip ->
+      xs
+      |> fmap reverse
+      |> Keyboard
+
+    VerticalFlip ->
+      xs
+      |> reverse
+      |> Keyboard
+
+    Shift n ->
+      xs
+      |> concat
+      |> Utils.rotate n
+      |> Split.chunksOf 10
+      |> Keyboard
+
+retypePassage :: String -> Keyboard -> Maybe String
+retypePassage passage newKeyboard =
+  passage
+  |> fmap Char.toUpper
+  |> traverse (\c -> HM.lookup c Keyboard.charToCoord)
+  >>= traverse (Keyboard.coordToChar newKeyboard)
diff --git a/users/wpcarro/assessments/brilliant/Keyboard.hs b/users/wpcarro/assessments/brilliant/Keyboard.hs
new file mode 100644
index 000000000000..13b5de0145aa
--- /dev/null
+++ b/users/wpcarro/assessments/brilliant/Keyboard.hs
@@ -0,0 +1,58 @@
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric #-}
+--------------------------------------------------------------------------------
+module Keyboard where
+--------------------------------------------------------------------------------
+import Utils
+import Data.Coerce
+import Data.Hashable (Hashable)
+import GHC.Generics (Generic)
+
+import qualified Data.List as List
+import qualified Data.HashMap.Strict as HM
+--------------------------------------------------------------------------------
+
+newtype Keyboard = Keyboard [[Char]]
+  deriving (Eq)
+
+instance Show Keyboard where
+  show (Keyboard xxs) =
+    xxs |> fmap printRow |> List.intercalate "\n"
+    where
+      printRow :: [Char] -> String
+      printRow xs =
+        xs |> fmap (\x -> '[':x:']':"") |> List.intercalate ""
+
+data Coord = Coord
+  { row :: Int
+  , col :: Int
+  } deriving (Eq, Show, Generic)
+
+instance Hashable Coord
+
+-- | List of characters to their QWERTY coordinatees.
+coords :: [(Char, Coord)]
+coords =
+  qwerty
+  |> coerce
+  |> fmap (zip [0..])
+  |> zip [0..]
+  |> fmap (\(row, xs) -> xs |> fmap (\(col, char) -> (char, Coord row col)))
+  |> mconcat
+
+-- | Mapping of characters to their coordinates on a QWERTY keyboard with the
+-- top-left corner as 0,0.
+charToCoord :: HM.HashMap Char Coord
+charToCoord = HM.fromList coords
+
+coordToChar :: Keyboard -> Coord -> Maybe Char
+coordToChar (Keyboard xxs) Coord{..} =
+  Just $ xxs !! row !! col
+
+qwerty :: Keyboard
+qwerty = Keyboard [ ['1','2','3','4','5','6','7','8','9','0']
+                  , ['Q','W','E','R','T','Y','U','I','O','P']
+                  , ['A','S','D','F','G','H','J','K','L',';']
+                  , ['Z','X','C','V','B','N','M',',','.','/']
+                  ]
diff --git a/users/wpcarro/assessments/brilliant/Main.hs b/users/wpcarro/assessments/brilliant/Main.hs
new file mode 100644
index 000000000000..e94c73bea287
--- /dev/null
+++ b/users/wpcarro/assessments/brilliant/Main.hs
@@ -0,0 +1,43 @@
+{-# LANGUAGE RecordWildCards #-}
+--------------------------------------------------------------------------------
+module Main where
+--------------------------------------------------------------------------------
+import Options.Applicative
+import Data.Semigroup ((<>))
+
+import qualified Transforms
+import qualified Keyboard
+import qualified App
+--------------------------------------------------------------------------------
+
+data CommandArgs = CommandArgs
+  { transforms :: String
+  , passage :: String
+  } deriving (Eq, Show)
+
+parseArgs :: Parser CommandArgs
+parseArgs =
+  CommandArgs <$> strOption
+                  ( long "transforms"
+                 <> short 't'
+                 <> help "String of transforms where (e.g. \"HHVS12VHVHS3\")" )
+              <*> strOption
+                  ( long "passage"
+                 <> short 'p'
+                 <> help "Input text to re-type" )
+
+main :: IO ()
+main = do
+  CommandArgs{..} <- execParser opts
+  case Transforms.fromString transforms of
+    Nothing -> putStrLn "You must provide valid input (e.g. \"HHVS12VHVHS3\")"
+    Just xs -> do
+      let keyboard = foldl App.transform Keyboard.qwerty (Transforms.optimize xs)
+      putStrLn $ "Typing: \"" ++ passage ++ "\"\nOn this keyboard:\n" ++ show keyboard
+      case App.retypePassage passage keyboard of
+        Nothing -> putStrLn $ "Looks like at least one of the characters in your input passage doesn't fit on our QWERTY keyboard: \n" ++ show Keyboard.qwerty
+        Just result -> putStrLn $ "Result: " ++ result
+  where
+    opts = info (parseArgs <**> helper)
+      ( fullDesc
+     <> progDesc "Transform a QWERTY keyboard using a string of commands")
diff --git a/users/wpcarro/assessments/brilliant/README.md b/users/wpcarro/assessments/brilliant/README.md
new file mode 100644
index 000000000000..60d7de4e25ae
--- /dev/null
+++ b/users/wpcarro/assessments/brilliant/README.md
@@ -0,0 +1,82 @@
+# Transform QWERTY
+
+Apply a series of transforms to a QWERTY keyboard then use the new keyboard to
+re-type a passage of text.
+
+## Environment
+
+You will need [Nix][nix] to build this program on your machine. The good news is
+that you won't need any Haskell-specific dependencies like `ghc`, `cabal`, or
+`stack`: just Nix.
+
+Once you have Nix installed, to build the program, run the following from this
+project's top-level directory:
+
+```shell
+$ nix-build
+```
+
+This should output an executable named `transform-keyboard` within a `result`
+directory:
+
+```shell
+$ tree result
+result
+โ””โ”€โ”€ transform-keyboard
+```
+
+### Testing
+
+To run the test suite, run the following from the project's top-level directory:
+
+```shell
+$ nix-shell
+$ runhaskell Spec.hs
+```
+
+[nix]: https://nixos.org/download.html
+
+## Usage
+
+Here are some `--help` and usage examples:
+
+```shell
+$ ./result/transform-keyboard --help
+Usage: transform-keyboard (-t|--transforms ARG) (-p|--passage ARG)
+  Transform a QWERTY keyboard using a string of commands
+
+Available options:
+  -t,--transforms ARG      String of transforms where (e.g. "HHVS12VHVHS3")
+  -p,--passage ARG         Input text to re-type
+  -h,--help                Show this help text
+```
+
+Now a working example:
+
+```shell
+$ ./result/transform-keyboard --transforms=HHVS12VHVHS3 --passage='Hello,Brilliant.'
+Typing: "Hello,Brilliant."
+On this keyboard:
+[H][J][K][L][;][Q][W][E][R][T]
+[Y][U][I][O][P][1][2][3][4][5]
+[6][7][8][9][0][Z][X][C][V][B]
+[N][M][,][.][/][A][S][D][F][G]
+Result: ZIVV4D/O3VV36APF
+```
+
+...and an example with an erroneous input (i.e. `!`):
+
+```shell
+$ ./result/transform-keyboard --transforms=HHVS12VHVHS3 --passage='Hello,Brilliant!'
+Typing: "Hello,Brilliant!"
+On this keyboard:
+[H][J][K][L][;][Q][W][E][R][T]
+[Y][U][I][O][P][1][2][3][4][5]
+[6][7][8][9][0][Z][X][C][V][B]
+[N][M][,][.][/][A][S][D][F][G]
+Looks like at least one of the characters in your input passage doesn't fit on our QWERTY keyboard:
+[1][2][3][4][5][6][7][8][9][0]
+[Q][W][E][R][T][Y][U][I][O][P]
+[A][S][D][F][G][H][J][K][L][;]
+[Z][X][C][V][B][N][M][,][.][/]
+```
diff --git a/users/wpcarro/assessments/brilliant/Spec.hs b/users/wpcarro/assessments/brilliant/Spec.hs
new file mode 100644
index 000000000000..e99e025641fa
--- /dev/null
+++ b/users/wpcarro/assessments/brilliant/Spec.hs
@@ -0,0 +1,103 @@
+--------------------------------------------------------------------------------
+module Spec where
+--------------------------------------------------------------------------------
+import Test.Hspec
+import Test.QuickCheck
+import Keyboard (Keyboard(..))
+import Transforms (Transform(..))
+import Data.Coerce
+import Utils
+
+import qualified App
+import qualified Keyboard
+import qualified Transforms
+--------------------------------------------------------------------------------
+
+main :: IO ()
+main = hspec $ do
+  describe "Keyboard.print" $ do
+    it "pretty-prints the keyboard" $ do
+      show Keyboard.qwerty == "[1][2][3][4][5][6][7][8][9][0]\n[Q][W][E][R][T][Y][U][I][O][P]\n[A][S][D][F][G][H][J][K][L][;]\n[Z][X][C][V][B][N][M][,][.][/]"
+
+  describe "Transforms.fromString" $ do
+    it "successfully parses a string of commands" $ do
+      Transforms.fromString "HHVS-12VHVHS3" ==
+        Just [ HorizontalFlip
+             , HorizontalFlip
+             , VerticalFlip
+             , Shift (-12)
+             , VerticalFlip
+             , HorizontalFlip
+             , VerticalFlip
+             , HorizontalFlip
+             , Shift 3
+             ]
+
+    it "returns Nothing when the input is invalid" $ do
+      Transforms.fromString "potato" == Nothing
+
+    it "return Nothing when the input is valid except for the end" $ do
+      Transforms.fromString "HVS10potato" == Nothing
+
+  describe "App.transform" $ do
+    it "flips any keyboard horizontally" $ do
+      property $ \first second third fourth ->
+        App.transform (Keyboard [first, second, third, fourth]) HorizontalFlip == do
+          Keyboard [ reverse first
+                   , reverse second
+                   , reverse third
+                   , reverse fourth
+                   ]
+
+    it "flips any keyboard vertically" $ do
+      property $ \first second third fourth ->
+        App.transform (Keyboard [first, second, third, fourth]) VerticalFlip == do
+          Keyboard $ reverse [first, second, third, fourth]
+
+    it "shifts any keyboard" $ do
+      property $ \first second third fourth n ->
+        App.transform (Keyboard [first, second, third, fourth]) (Shift n)
+        |> (coerce :: Keyboard -> [[Char]])
+        |> concat ==
+          [first, second, third, fourth]
+            |> concat
+            |> Utils.rotate n
+
+    it "flips a QWERTY keyboard horizontally" $ do
+      App.transform Keyboard.qwerty HorizontalFlip == do
+        Keyboard [ ['0','9','8','7','6','5','4','3','2','1']
+                 , ['P','O','I','U','Y','T','R','E','W','Q']
+                 , [';','L','K','J','H','G','F','D','S','A']
+                 , ['/','.',',','M','N','B','V','C','X','Z']
+                 ]
+
+    it "flips a keyboard vertically" $ do
+      App.transform Keyboard.qwerty VerticalFlip == do
+        Keyboard [ ['Z','X','C','V','B','N','M',',','.','/']
+                 , ['A','S','D','F','G','H','J','K','L',';']
+                 , ['Q','W','E','R','T','Y','U','I','O','P']
+                 , ['1','2','3','4','5','6','7','8','9','0']
+                 ]
+
+    it "shifts a keyboard left N times" $ do
+      App.transform Keyboard.qwerty (Shift 2) == do
+        Keyboard [ ['3','4','5','6','7','8','9','0','Q','W']
+                 , ['E','R','T','Y','U','I','O','P','A','S']
+                 , ['D','F','G','H','J','K','L',';','Z','X']
+                 , ['C','V','B','N','M',',','.','/','1','2']
+                 ]
+
+    it "shifts right negative amounts" $ do
+      App.transform Keyboard.qwerty (Shift (-3)) == do
+        Keyboard [ [',','.','/','1','2','3','4','5','6','7']
+                 , ['8','9','0','Q','W','E','R','T','Y','U']
+                 , ['I','O','P','A','S','D','F','G','H','J']
+                 , ['K','L',';','Z','X','C','V','B','N','M']
+                 ]
+
+  describe "Transforms.optimize" $ do
+    it "removes superfluous horizontal transformations" $ do
+      Transforms.optimize [HorizontalFlip, HorizontalFlip] == []
+
+    it "removes superfluous vertical transformations" $ do
+      Transforms.optimize [VerticalFlip, VerticalFlip] == []
diff --git a/users/wpcarro/assessments/brilliant/Transforms.hs b/users/wpcarro/assessments/brilliant/Transforms.hs
new file mode 100644
index 000000000000..d8df8f8372e0
--- /dev/null
+++ b/users/wpcarro/assessments/brilliant/Transforms.hs
@@ -0,0 +1,52 @@
+--------------------------------------------------------------------------------
+module Transforms where
+--------------------------------------------------------------------------------
+import Control.Applicative ((<|>))
+import Text.ParserCombinators.ReadP
+--------------------------------------------------------------------------------
+
+data Transform = VerticalFlip
+               | HorizontalFlip
+               | Shift Int
+               deriving (Eq, Show)
+
+digit :: ReadP Char
+digit =
+  satisfy (\c -> c >= '0' && c <= '9')
+
+command :: ReadP Transform
+command = vertical
+      <|> horizontal
+      <|> shift
+  where
+    vertical =
+      char 'V' >> pure VerticalFlip
+
+    horizontal =
+      char 'H' >> pure HorizontalFlip
+
+    shift = do
+      _ <- char 'S'
+      negative <- option Nothing $ fmap Just (satisfy (== '-'))
+      n <- read <$> many1 digit
+      case negative of
+        Nothing -> pure $ Shift n
+        Just _  -> pure $ Shift (-1 * n)
+
+-- | Attempt to remove redundant transformations.
+-- | Here are some rules that I'd like to support but may not have time for:
+-- | - All even-numbered flips (w/o intermittent shifts) can become zero
+-- | - All odd-numbered flips (w/o intermittent shifts) can become 1
+-- | - All shifts can be be reduce to the absolute value of shifts
+optimize :: [Transform] -> [Transform]
+optimize [] = []
+optimize [x] = [x]
+optimize (VerticalFlip:VerticalFlip:xs) = optimize xs
+optimize (HorizontalFlip:HorizontalFlip:xs) = optimize xs
+optimize xs = xs
+
+fromString :: String -> Maybe [Transform]
+fromString x =
+  case readP_to_S (manyTill command eof) x of
+   [(res, "")] -> Just res
+   _           -> Nothing
diff --git a/users/wpcarro/assessments/brilliant/Utils.hs b/users/wpcarro/assessments/brilliant/Utils.hs
new file mode 100644
index 000000000000..c69d00333b8e
--- /dev/null
+++ b/users/wpcarro/assessments/brilliant/Utils.hs
@@ -0,0 +1,13 @@
+--------------------------------------------------------------------------------
+module Utils where
+--------------------------------------------------------------------------------
+import Data.Function ((&))
+--------------------------------------------------------------------------------
+
+(|>) :: a -> (a -> b) -> b
+(|>) = (&)
+
+-- | Rotate `xs` as a cycle `n` times.
+rotate :: Int -> [a] -> [a]
+rotate n xs = take size . drop (n `mod` size) . cycle $ xs
+  where size = length xs
diff --git a/users/wpcarro/assessments/brilliant/default.nix b/users/wpcarro/assessments/brilliant/default.nix
new file mode 100644
index 000000000000..886ba87e1caf
--- /dev/null
+++ b/users/wpcarro/assessments/brilliant/default.nix
@@ -0,0 +1,16 @@
+let
+  briefcase = import <briefcase> {};
+in briefcase.buildHaskell.program {
+  name = "transform-keyboard";
+  srcs = builtins.path {
+    path = ./.;
+    name = "transform-keyboard-src";
+  };
+  deps = hpkgs: with hpkgs; [
+    optparse-applicative
+    unordered-containers
+    split
+    rio
+  ];
+  ghcExtensions = [];
+}
diff --git a/users/wpcarro/assessments/brilliant/shell.nix b/users/wpcarro/assessments/brilliant/shell.nix
new file mode 100644
index 000000000000..d0a6c7e5e6f5
--- /dev/null
+++ b/users/wpcarro/assessments/brilliant/shell.nix
@@ -0,0 +1,16 @@
+let
+  pkgs = import (builtins.fetchGit {
+    url = "https://github.com/NixOS/nixpkgs-channels";
+    ref = "nixos-20.03";
+    rev = "afa9ca61924f05aacfe495a7ad0fd84709d236cc";
+  }) {};
+in pkgs.mkShell {
+  buildInputs = with pkgs; [
+    (haskellPackages.ghcWithPackages (hpkgs: with hpkgs; [
+      hspec
+      optparse-applicative
+      unordered-containers
+      split
+    ]))
+  ];
+}