Start to implement lock and key system

src/Dodge/Room/Placement.hs

@@ -3,18 +3,20 @@ module Dodge.Room.Placement
   where
 import Dodge.Data
 import Dodge.LevelGen.Data
-import Picture
+import Dodge.Room.Data
 import Dodge.Creature.Inanimate
-
+import Picture
 import Geometry
 
+import Data.List
+import Control.Lens
+
 
 putLamp = PutCrit lamp
 
 singleBlock :: Point2 -> [PlacementSpot]
 singleBlock a = [PS a 0 $ PutBlock [5,20,20] (greyN 0.5)
                                         $ reverse $ rectNSWE 10 (-10) (-10) 10]
-
 {-
 Places a line of blocks between two points.
 Width 9, also extends out from each point by 9.
@@ -88,3 +90,31 @@ baseWindowPane = Block
     , _blShadows = []
     , _blDegrades = [5,5]
     }
+
+{-
+Replaces instances of a given 'PutID' with 'PSType's drawn from a list.
+-}
+replacePutID 
+    :: Int      -- ^ The id of 'PutID' to be replaced
+    -> [PSType] -- ^ List of replacements
+    -> Room 
+    -> Room
+replacePutID i psts r =
+    r & rmPS %~ flip (subZipWith (isPutID i) (\ps pt -> ps & psType .~ pt)) psts
+
+{-
+Partition a list by a predicate, apply a zip to those elements 
+that satisfy the predicate, concatenate 
+the new zipped list and the other (unchanged) half.
+-}
+subZipWith 
+    :: (a -> Bool)      -- ^ Filter: elements to apply zip to
+    -> (a -> b -> a)    -- ^ Combining function
+    -> [a]              -- ^ List to be partition
+    -> [b]              -- ^ Modifying list
+    -> [a]
+subZipWith f g xs ys =
+    let (zs,ws) = partition f xs
+    in  zipWith g zs ys ++ ws
+
+isPutID i ps = Just i == ps ^? psType . putID