Day01: solve part 1

aoc.cabal

@@ -132,6 +132,7 @@ test-suite spec
   main-is: Spec.hs
   other-modules:
       AoCSpec.UtilSpec
+      AoCSpec.Y2023Spec
       SpecHook
       Paths_aoc
   autogen-modules:

src/AoC.hs

@@ -1,7 +1,8 @@
-{-# LANGUAGE OverloadedStrings #-}
-
 module AoC (
   defaultMain,
+  runAoC,
+  module AoC.Day,
+  module AoC.Year,
 ) where
 
 import AoC.Day
@@ -14,17 +15,18 @@ import System.IO.Error qualified as IOError
 
 import AoC.Y2023 qualified as Y2023
 
-runAoC :: (MonadIO m) => [String] -> m ()
-runAoC _args = do
-  riddle <- loadRiddle Y2023 D01
-  result <- Y2023.solve D01 riddle
-  print result
+runAoC :: (MonadIO m) => Year -> Day -> m (Either Text Solution)
+runAoC y d = do
+  riddle <- loadRiddle y d
+  solve y d riddle
+
+solve :: (MonadIO m) => Year -> Day -> Riddle -> m (Either Text Solution)
+solve Y2023 = Y2023.solve
+solve y = \_ _ -> pure $ Left $ show y <> ": not implementedi"
 
 handleError :: IOError.IOError -> IO ()
 handleError e = do
   hPutStrLn stderr $ "I ran into an issue: " <> show e
 
 defaultMain :: IO ()
-defaultMain = do
-  args <- getArgs
-  Exception.catch (runAoC args) handleError
+defaultMain = Exception.catch (runAoC Y2023 D01 >>= print) handleError

src/AoC/Y2023/D01.hs

@@ -1,6 +1,24 @@
 module AoC.Y2023.D01 (solve) where
 
 import AoC.Riddle
+import Data.Char (digitToInt, isDigit)
+import Relude.Unsafe (fromJust)
+
+digits :: String -> [Int]
+digits = fmap digitToInt . filter isDigit
+
+digits' :: String -> NonEmpty Int
+digits' = fromJust . nonEmpty . digits
+
+calibrationValue :: String -> Int
+calibrationValue s = firstDigit * 10 + lastDigit
+ where
+  ds = digits' s
+  firstDigit = head ds
+  lastDigit = last ds
+
+solvePart1 :: Text -> Integer
+solvePart1 = fromIntegral . sum . fmap (calibrationValue . toString) . lines
 
 solve :: (MonadIO m) => Text -> m (Either Text Solution)
-solve _ = pure $ Left "not yet implemented"
+solve input = pure $ Right [solvePart1 input]

test/spec/AoCSpec/Y2023Spec.hs

@@ -0,0 +1,10 @@
+module AoCSpec.Y2023Spec (spec) where
+
+import AoC
+import Test.Hspec
+
+spec :: Spec
+spec = do
+  describe "Day 1" do
+    it "calculates correctly" do
+      runAoC Y2023 D01 `shouldReturn` Right [54331]