Add a very basic, naive auto-move command

Add a very basic, naive auto-move command, which just steps the player
in a direction until they collide with something, regardless of any
surrounding beasties who might want to eat them.

There's a lot of other stuff going on here - in order to get this
working the way I wanted with a slight (I settled on 50ms) delay between
every step in these autocommands while still redrawing in between I had
to do all the extra machinery for custom Brick events with a channel,
and then at the same time adding the bits for actually executing
autocommands in a general fashion (because there will definitely be
more!) hit my threshold for size for App.hs which sent me on a big
journey to break it up into smaller files -- which seems actually like
it was quite successful. Hopefully this will help with compile times
too, though App.hs is still pretty slow (maybe more to do here).

1 files changed, 161 insertions, 0 deletions

diff --git a/src/Xanthous/App/Prompt.hs b/src/Xanthous/App/Prompt.hs
new file mode 100644
index 0000000000..6704a601da
--- /dev/null
+++ b/src/Xanthous/App/Prompt.hs
@@ -0,0 +1,161 @@
+{-# LANGUAGE UndecidableInstances #-}
+--------------------------------------------------------------------------------
+module Xanthous.App.Prompt
+  ( handlePromptEvent
+  , clearPrompt
+  , prompt
+  , prompt_
+  , confirm_
+  , confirm
+  , menu
+  , menu_
+  ) where
+--------------------------------------------------------------------------------
+import           Xanthous.Prelude
+--------------------------------------------------------------------------------
+import           Brick (BrickEvent(..), Next)
+import           Brick.Widgets.Edit (handleEditorEvent)
+import           Data.Aeson (ToJSON, object)
+import           Graphics.Vty.Input.Events (Event(EvKey), Key(..))
+import           GHC.TypeLits (TypeError, ErrorMessage(..))
+--------------------------------------------------------------------------------
+import           Xanthous.App.Common
+import           Xanthous.Data (move)
+import           Xanthous.Command (directionFromChar)
+import           Xanthous.Data.App (ResourceName, AppEvent)
+import           Xanthous.Game.Prompt
+import           Xanthous.Game.State
+import qualified Xanthous.Messages as Messages
+--------------------------------------------------------------------------------
+
+handlePromptEvent
+  :: Text -- ^ Prompt message
+  -> Prompt AppM
+  -> BrickEvent ResourceName AppEvent
+  -> AppM (Next GameState)
+
+handlePromptEvent _ (Prompt Cancellable _ _ _ _) (VtyEvent (EvKey KEsc []))
+  = clearPrompt >> continue
+handlePromptEvent _ pr (VtyEvent (EvKey KEnter []))
+  = clearPrompt >> submitPrompt pr >> continue
+
+handlePromptEvent _ pr@(Prompt _ SConfirm _ _ _) (VtyEvent (EvKey (KChar 'y') []))
+  = clearPrompt >> submitPrompt pr >> continue
+
+handlePromptEvent _ (Prompt _ SConfirm _ _ _) (VtyEvent (EvKey (KChar 'n') []))
+  = clearPrompt >> continue
+
+handlePromptEvent
+  msg
+  (Prompt c SStringPrompt (StringPromptState edit) pri cb)
+  (VtyEvent ev)
+  = do
+    edit' <- lift $ handleEditorEvent ev edit
+    let prompt' = Prompt c SStringPrompt (StringPromptState edit') pri cb
+    promptState .= WaitingPrompt msg prompt'
+    continue
+
+handlePromptEvent _ (Prompt _ SDirectionPrompt _ _ cb)
+  (VtyEvent (EvKey (KChar (directionFromChar -> Just dir)) []))
+  = clearPrompt >> cb (DirectionResult dir) >> continue
+handlePromptEvent _ (Prompt _ SDirectionPrompt _ _ _) _ = continue
+
+handlePromptEvent _ (Prompt _ SMenu _ items' cb) (VtyEvent (EvKey (KChar chr) []))
+  | Just (MenuOption _ res) <- items' ^. at chr
+  = clearPrompt >> cb (MenuResult res) >> continue
+  | otherwise
+  = continue
+
+handlePromptEvent
+  msg
+  (Prompt c SPointOnMap (PointOnMapPromptState pos) pri cb)
+  (VtyEvent (EvKey (KChar (directionFromChar -> Just dir)) []))
+  = let pos' = move dir pos
+        prompt' = Prompt c SPointOnMap (PointOnMapPromptState pos') pri cb
+    in promptState .= WaitingPrompt msg prompt'
+       >> continue
+handlePromptEvent _ (Prompt _ SPointOnMap _ _ _) _ = continue
+
+handlePromptEvent
+  _
+  (Prompt Cancellable _ _ _ _)
+  (VtyEvent (EvKey (KChar 'q') []))
+  = clearPrompt >> continue
+handlePromptEvent _ _ _ = continue
+
+clearPrompt :: AppM ()
+clearPrompt = promptState .= NoPrompt
+
+class NotMenu (pt :: PromptType)
+instance NotMenu 'StringPrompt
+instance NotMenu 'Confirm
+instance NotMenu 'DirectionPrompt
+instance NotMenu 'PointOnMap
+instance NotMenu 'Continue
+instance TypeError ('Text "Cannot use `prompt` or `prompt_` for menu prompts"
+                    ':$$: 'Text "Use `menu` or `menu_` instead")
+         => NotMenu ('Menu a)
+
+prompt
+  :: forall (pt :: PromptType) (params :: Type).
+    (ToJSON params, SingPromptType pt, NotMenu pt)
+  => [Text]                     -- ^ Message key
+  -> params                     -- ^ Message params
+  -> PromptCancellable
+  -> (PromptResult pt -> AppM ()) -- ^ Prompt promise handler
+  -> AppM ()
+prompt msgPath params cancellable cb = do
+  let pt = singPromptType @pt
+  msg <- Messages.message msgPath params
+  p <- case pt of
+    SPointOnMap -> do
+      charPos <- use characterPosition
+      pure $ mkPointOnMapPrompt cancellable charPos cb
+    SStringPrompt -> pure $ mkPrompt cancellable pt cb
+    SConfirm -> pure $ mkPrompt cancellable pt cb
+    SDirectionPrompt -> pure $ mkPrompt cancellable pt cb
+    SContinue -> pure $ mkPrompt cancellable pt cb
+    SMenu -> error "unreachable"
+  promptState .= WaitingPrompt msg p
+
+prompt_
+  :: forall (pt :: PromptType).
+    (SingPromptType pt, NotMenu pt)
+  => [Text] -- ^ Message key
+  -> PromptCancellable
+  -> (PromptResult pt -> AppM ()) -- ^ Prompt promise handler
+  -> AppM ()
+prompt_ msg = prompt msg $ object []
+
+confirm
+  :: ToJSON params
+  => [Text] -- ^ Message key
+  -> params
+  -> AppM ()
+  -> AppM ()
+confirm msgPath params
+  = prompt @'Confirm msgPath params Cancellable . const
+
+confirm_ :: [Text] -> AppM () -> AppM ()
+confirm_ msgPath = confirm msgPath $ object []
+
+menu :: forall (a :: Type) (params :: Type).
+       (ToJSON params)
+     => [Text]                            -- ^ Message key
+     -> params                            -- ^ Message params
+     -> PromptCancellable
+     -> Map Char (MenuOption a)           -- ^ Menu items
+     -> (PromptResult ('Menu a) -> AppM ()) -- ^ Menu promise handler
+     -> AppM ()
+menu msgPath params cancellable items' cb = do
+  msg <- Messages.message msgPath params
+  let p = mkMenu cancellable items' cb
+  promptState .= WaitingPrompt msg p
+
+menu_ :: forall (a :: Type).
+        [Text]                            -- ^ Message key
+      -> PromptCancellable
+      -> Map Char (MenuOption a)           -- ^ Menu items
+      -> (PromptResult ('Menu a) -> AppM ()) -- ^ Menu promise handler
+      -> AppM ()
+menu_ msgPath = menu msgPath $ object []