From 4411868464389611bffad9b3a8bbd76d1178056c Mon Sep 17 00:00:00 2001
From: Andrew Maier <andrew@maier.name>
Date: Thu, 9 Dec 2021 15:53:41 +0100
Subject: [PATCH] Finished Day02

---
 day02/lib/Day02.hs | 32 ++++++++++++++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/day02/lib/Day02.hs b/day02/lib/Day02.hs
index 3b58c26..5081c3d 100644
--- a/day02/lib/Day02.hs
+++ b/day02/lib/Day02.hs
@@ -5,17 +5,45 @@ import Text.Read (readMaybe)
 
 data Move = Horizontal Int | Depth Int deriving Show
 
+
+data Position = Position {hPos :: Int, depth :: Int, aim::Int} deriving Show
+
+
+initialPosition :: Position
+initialPosition = Position {hPos =0, depth = 0, aim = 0}
+
+
+updatePosition :: Position -> Move -> Position
+updatePosition p@(Position {hPos = h}) (Horizontal m) = p{hPos = h + m}
+updatePosition p@(Position {depth = d}) ( Depth m) = p{depth = d + m}
+
+updatePosition' :: Position -> Move -> Position
+updatePosition' p@(Position {hPos=h, depth=d,  aim=a}) (Horizontal m) = p{hPos=h+m, depth =d+a*m}
+updatePosition' p@(Position {hPos=h, depth=d, aim=a}) (Depth m) = p{aim=a+m}
+
 readDataLines:: (String -> Maybe a) -> String -> Either String [a]
 readDataLines f s = case mapM f (lines s) of
                       Just xs -> Right xs
                       Nothing -> Left "Error parsing string"
 
+finalPosition :: [Move] -> Position
+finalPosition =  foldl updatePosition initialPosition
+
+finalPosition' :: [Move] -> Position
+finalPosition' = foldl updatePosition' initialPosition
+
+calcResult:: Position -> Int
+calcResult  Position {hPos = h, depth =d } = h*d
+
 day02Part1 :: String -> String
-day02Part1 _ = "Day02 Part1"
+day02Part1 s = case readDataLines readMove s of
+                 Right xs -> show  . calcResult . finalPosition $ xs
+                 Left e -> e
 
 
 day02Part2 :: String -> String
-day02Part2 _ = "Day02 Part2"
+day02Part2 s = case readDataLines readMove s of
+                 Right xs -> show . calcResult . finalPosition' $ xs
 
 readDirection ::String -> Maybe (Int -> Move)
 readDirection "forward" = Just Horizontal