Add day 1 part 1

2023/2-1.nix

@@ -0,0 +1,32 @@
+{ lib, input }:
+
+with builtins; with lib; rec {
+  lines = splitString "\n" input;
+
+  lineToId = line: removePrefix "Game " (head (splitString ": " line));
+  lineToRawRGBListList = line:
+    map (splitString ", ")
+      (splitString "; "
+        (last (splitString ": " line)));
+
+  # [ "1 blue" "2 red" ] => { blue = 1; red = 2; }
+  parseRawRGBList = rawList:
+    listToAttrs (map (entry: let
+      parts = splitString " " entry;
+    in {
+      name = last parts;
+      value = head parts;
+    }) rawList);
+
+  # [ { fst = "1"; snd = [ { blue = 1; red = 2; green = 123; } ]; } ]
+  games = zipLists (map lineToId lines) (map (map parseRawRGBList) (map lineToRawRGBListList lines));
+
+  rgbPossible = rgb:
+    (fromJSON (rgb.red or "0")) <= 12 &&
+    (fromJSON (rgb.green or "0")) <= 13 &&
+    (fromJSON (rgb.blue or "0")) <= 14;
+
+  possibleGamesLists = filter (game: all rgbPossible game.snd) games;
+
+  result = foldl' add 0 (map (game: fromJSON game.fst) possibleGamesLists);
+}