1 files changed, 16 insertions, 1 deletions

diff --git a/src/Main.hs b/src/Main.hs
index db49e14..9a51332 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -95,6 +95,7 @@ main = do
                                     , cmd "align" alignEntity "Align the focused entity to a faction – creating it, if necessary"
                                     , cmd "name" nameEntity "Name the current entity overriding previous name assignments"
                                     , cmd "spawn" spawnEntity "Create a new entity from an archetype focusing on it"
+                                    , cmd "replace" replaceEntity "Replace the focused entity with a different one carrying over some values"
                                     , cmd "spawn'" spawnFaction "Create a new faction and spawn multiple copies of an archetype in it"
                                     , cmd "test" rollTest "Roll a test using the stats of the currently focused entity"
                                     , cmd "combat" entitySeqVal "Roll sequence value for the current focus and enter combat"
@@ -326,11 +327,25 @@ remove = withFocus $ \ident -> do
     blur
 
 -- Manage Entity
-spawnEntity :: Completable Entity -> Sh GameState ()
+spawnEntity, replaceEntity :: Completable Entity -> Sh GameState ()
 spawnEntity = withArg $ \entity -> do
   identifier <- use gNextId'
   modify $ insertEntity entity
   gFocus ?= identifier
+replaceEntity = withArg $ \entity -> void . withFocus' $ \old -> do
+  let oldStats = old ^. eStats
+  modifying (gFocus' . eStats) . execState $ do
+    put $ entity ^. eStats
+    let
+      copy :: st -> Traversal' st a -> State st ()
+      copy from lens = do
+        case preview lens from of
+          Just a  -> lens .= a
+          Nothing -> return ()
+    copy oldStats sSeqVal
+    copy oldStats sTimer
+    copy oldStats sModifiers
+    copy oldStats sEquipment
 
 nameEntity :: String -> Sh GameState ()
 nameEntity ('#':_) = shellPutErrLn "We do not allow names that might shadow explicit access to entities via their number (‘#<n>’)"