More challenge levels

app/Model.hs

@@ -139,13 +139,13 @@ moveBlock' world locMap visited loc loc' dir name box enters offset =
          do (n,b) <- Map.lookup loc' locMap
             (locI, offset') <- enterLoc world n b dir offset
             if Set.member locI enters then
-              moveEpsilon
+             do epsilon <- findEpsilon world (locName locI)
+                moveEpsilon epsilon
             else
               moveBlock' world locMap visited loc locI dir name box (Set.insert locI enters) offset'
 
-        moveEpsilon =
-         do epsilon <- findEpsilon world (locName loc')
-            let eBox = boxIx world epsilon
+        moveEpsilon epsilon =
+         do let eBox = boxIx world epsilon
             (locI, offset') <- enterLoc world epsilon eBox dir offset
             moveBlock' world locMap visited loc locI dir name box (Set.insert locI enters) offset'
 

app/Parser.hs

@@ -62,6 +62,12 @@ parseBoring =
       "interesting" -> pure False
       _             -> empty
 
+parseHeight :: ReadP (Maybe Int)
+parseHeight = option Nothing $
+ do "height" <- token
+    Just <$> integer
+
+
 parseBlock :: ReadP (Char, Box, [(Char, Location)])
 parseBlock =
  do cmd <- token
@@ -70,9 +76,10 @@ parseBlock =
        do [name] <- token
           color <- parseColor
           boring <- parseBoring
+          height <- parseHeight
           skipMany (satisfy (' '==))
           _ <- char '\n'
-          xs1 <- parseWalls
+          xs1 <- parseWalls height
           let locs = findLocs name xs1
           let b = Box Nothing (Original (walls xs1)) color boring
           pure (name, b, locs)
@@ -92,18 +99,20 @@ parseBlock =
        do [name] <- token
           [target] <- token
           color <- parseColor
+          height <- parseHeight
           skipMany (satisfy (' '==))
           _ <- char '\n'
-          xs1 <- parseWalls
+          xs1 <- parseWalls height
           let locs = findLocs name xs1
           let b = Box Nothing (Epsilon target (walls xs1)) color False
           pure (name, b, locs)
       _ -> empty
 
-parseWalls :: ReadP [String]
-parseWalls =
+parseWalls :: Maybe Int -> ReadP [String]
+parseWalls height =
  do row0 <- munch1 ('\n' /=) <* char '\n'
-    rows <- replicateM (length row0 - 1) (munch1 ('\n' /=) <* char '\n')
+    let h = maybe (length row0 - 1) (subtract 1) height
+    rows <- replicateM h (munch1 ('\n' /=) <* char '\n')
     pure (row0:rows)
 
 token :: ReadP String