refactoring in playground, use zip file for web

playground/samples/aoc2023/Day2.newt

@@ -0,0 +1,92 @@
+module Day2
+
+/-
+ I ported a couple of Advent of Code 2023 solutions from Lean4
+ as an early test case. Here I've adapted them to the web playground
+ by replacing `readFile` with an async `fetchText`.
+-/
+
+import Web
+
+Draw : U
+Draw = Int × Int × Int
+
+data Game : U where
+  MkGame : Int -> List Draw -> Game
+
+-- Original had class and instance...
+-- Add, Sub, Mul, Neg
+
+max : Int -> Int -> Int
+max x y = case x < y of
+  True => y
+  False => x
+
+pfunc repr : {a : U} -> a -> String := `(a,o) => ''+o`
+pfunc jrepr : {a : U} -> a -> String := `(a,o) => JSON.stringify(o, null, '  ')`
+pfunc toInt : String -> Int := `s => Number(s)`
+
+maxd : Draw -> Draw -> Draw
+maxd (a,b,c) (d,e,f) = (max a d, max b e, max c f)
+
+lte : Draw -> Draw -> Bool
+lte (a,b,c) (d,e,f) = a <= d && b <= e && c <= f
+
+parseColor : String -> Either String Draw
+parseColor line = case split line " " of
+  (n :: "red" :: Nil) => Right (toInt n,0,0)
+  (n :: "green" :: Nil) => Right (0,toInt n,0)
+  (n :: "blue" :: Nil) => Right (0,0,toInt n)
+  x => Left $ "Bad draw" ++ repr x
+
+parseDraw : String -> Either String Draw
+parseDraw line = case mapM {Either String} parseColor $ split line ", " of
+  Right parts => Right $ foldl maxd (0,0,0) parts
+  Left err => Left err
+
+parseGame : String -> Either String Game
+parseGame line =
+  -- Need the Idris | sugar...
+  case split line ": " of
+    -- this is splitting on the Nil instead of the a
+    (a :: b :: Nil) => case split a " " of
+      ("Game" :: ns :: Nil) =>
+        let num = toInt ns in
+        case mapM {Either String} parseDraw $ split b "; " of
+          Right parts => Right $ MkGame num parts
+          Left err => Left err
+      _ => Left "No Game"
+    _ => Left $ "No colon in " ++ line
+
+part1 : List Game -> Int
+part1 Nil = 0
+part1 (MkGame n parts :: rest) =
+  let total = foldl maxd (0,0,0) parts in
+  case lte total (12,13,14) of
+    True => n + part1 rest
+    False => part1 rest
+
+part2 : List Game -> Int
+part2 Nil = 0
+part2 (MkGame n parts :: rest) =
+  case foldl maxd (0,0,0) parts of
+    (a,b,c) => a * b * c + part2 rest
+
+-- readFile not in browser / playground
+
+run : String -> Async Unit
+run fn = do
+  text <- fetchText fn
+  case mapM {Either String} parseGame (split (trim text) "\n") of
+    Left err => putStrLn $ "fail " ++ err
+    Right games => do
+      putStrLn "part1"
+      printLn (part1 games)
+      putStrLn "part2"
+      printLn (part2 games)
+
+main : IO Unit
+main = runAsync (do
+  run "aoc2023/day2/eg.txt"
+  run "aoc2023/day2/input.txt"
+  )