1 files changed, 87 insertions, 0 deletions
diff --git a/app/Scratchy/Syntax.hs b/app/Scratchy/Syntax.hs
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+module Scratchy.Syntax where
+
+import Graphics.Gloss.Interface.Pure.Game
+
+
+-- Types
+------------------------------------------------------------
+
+type Duration  = Int
+type Pos       = (Float, Float)
+type Cell      = (Int, Int)
+type SpritePtr = Int
+
+
+-- Constants
+------------------------------------------------------------
+
+cellsPerSec :: Float
+cellsPerSec = 5
+
+gridW, gridH :: Int
+gridW = 30
+gridH = 30 -- FIXME: move.
+
+inBounds :: (Int,Int) -> Bool
+inBounds (x,y) = x >= 0 && x < gridW && y >= 0 && y < gridH
+
+cellSize :: Float
+cellSize = 30
+
+winW, winH :: Int
+winW = round (fromIntegral gridW * cellSize)
+winH = round (fromIntegral gridH * cellSize)
+
+
+-- Direction
+------------------------------------------------------------
+
+data Dir = U | D | L | R deriving (Eq,Ord,Show)
+
+dirVec :: Dir -> (Int, Int)
+dirVec U = (0, 1)
+dirVec D = (0,-1)
+dirVec L = (-1,0)
+dirVec R = (1, 0)
+
+nextCell :: Dir -> (Int, Int) -> (Int, Int)
+nextCell d (cx,cy) =
+  let (dx,dy) = dirVec d
+  in (cx + dx, cy + dy)
+
+
+-- Syntax
+------------------------------------------------------------
+
+data InspectionResult
+  = HasBarrier | HasSprite | IsFree
+
+data SProg a
+  = Pure a
+
+  -- Event listening
+  | OnKeyEvent Key (SProg ()) (SProg a) -- Listener for a specific key
+  | OnTargetReached SpritePtr (Cell -> SProg ()) (SProg a) -- Listener for a specific sprite
+  | OnTargetUpdated SpritePtr (Cell -> Cell -> SProg ()) (SProg a) -- Listener for a specific sprite
+  | OnBarrierHit SpritePtr (Cell -> Cell -> SProg ()) (SProg a)
+
+  -- Sprite and grid actions
+  | NewSprite Cell Picture (SpritePtr -> SProg a)
+  | SetColor SpritePtr Color (SProg a)
+  | SetTarget SpritePtr Cell (SProg a)
+  | GetTarget SpritePtr (Cell -> SProg a)
+  | SetBackgroundColor Color (SProg a)
+  | InspectCell Cell (InspectionResult -> SProg a)
+
+  -- Timer
+  | After Duration (SProg ()) (SProg a)
+  deriving Functor
+
+
+-- Combining programs
+------------------------------------------------------------
+
+combine :: SProg () -> SProg () -> SProg ()
+combine = undefined -- Fill this in
+
+