pituicat/src/Affection.hs

{-# LANGUAGE RecordWildCards #-}
module Affection
    ( withAffection
    -- , withWindow
    -- , withDefaultWindow
    , delaySec
    , get
    , put
    , module A
    ) where

import qualified SDL
import qualified SDL.Internal.Numbered as SDL (toNumber)
import qualified SDL.Raw as Raw
import qualified GEGL as G

import qualified Data.Text as T
import Data.Maybe

import System.Clock

import Control.Monad.Loops
import Control.Monad.State
import Control.Concurrent.MVar

import Foreign.C.Types (CInt(..))
import Foreign.Storable (peek)

import Affection.Types as A
import Affection.Draw as A

import qualified BABL as B

-- | Main function which bootstraps everything else.
withAffection
  :: AffectionConfig us -- ^ Configuration of the Game and its engine.
  -> IO ()
withAffection AffectionConfig{..} = do
  case initComponents of
    All ->
      SDL.initializeAll
    Only is ->
      SDL.initialize is
  G.gegl_init
  execTime <- newMVar =<< getTime Monotonic
  window <- SDL.createWindow windowTitle windowConfig
  oldSurf@(SDL.Surface ptr _) <- SDL.getWindowSurface window
  rawSurfacePtr <- Raw.convertSurfaceFormat ptr (SDL.toNumber SDL.ABGR8888) 0
  let surface = (flip SDL.Surface Nothing) rawSurfacePtr
      bablFormat = B.PixelFormat B.RGBA B.CFu8
  pixels <- SDL.surfacePixels surface
  format <- B.babl_format bablFormat
  SDL.V2 (CInt rw) (CInt rh) <- SDL.surfaceDimensions surface
  pixelFormat <- peek . Raw.surfaceFormat =<< peek rawSurfacePtr
  let (w, h) = (fromIntegral rw, fromIntegral rh)
      stride = fromIntegral (Raw.pixelFormatBytesPerPixel pixelFormat) * w
      cpp    = B.babl_components_per_pixel bablFormat
  initContainer <- return . (\x -> AffectionData
    { quitEvent       = False
    , userState       = x
    , drawWindow      = window
    , drawSurface     = surface
    , drawStack       = []
    }) =<< loadState surface
  (_, nState) <- runStateT ( A.runState $ do
    preLoop
    whileM_ (do
        current <- get
        return $ not $ A.quitEvent current
      )
      (do
        now      <- liftIO $ getTime Monotonic
        lastTime <- liftIO $ fromMaybe now <$> tryReadMVar execTime
        ad <- get
        mapM_ (invalidateDrawRequest pixels format stride cpp) $ drawStack ad
        put $ ad
          { drawStack = [] }
        drawLoop
        ad <- get
        clear <- return . catMaybes =<< mapM (handleDrawRequest pixels format stride cpp) (drawStack ad)
        put $ ad
          { drawStack = clear }
        liftIO $ SDL.surfaceBlit surface Nothing oldSurf Nothing
        updateLoop $ (fromIntegral $ toNanoSecs $ diffTimeSpec lastTime now) /
          (fromIntegral 10 ^ 9)
        _ <- liftIO $ swapMVar execTime $ now
        return ()
      )
    ) initContainer
  G.gegl_exit
  cleanUp $ userState nState
  SDL.quit

-- -- | DEPRECATED!
-- -- Function for bootstraping a window.
-- withWindow :: Monad m => T.Text -> WindowConfig -> SDL.RendererConfig -> RenderT m a -> IO ()
-- withWindow title wconf rconf ops = do
--   window <- SDL.createWindow title wconf
--   -- I don't need a renderer here, i need a surface
--   renderer <- SDL.createRenderer window (-1) rconf
--   surface <- SDL.getWindowSurface window
--   G.gegl_init
--   -- I think I need some AffectionT or someting similar here and not a RenderT
--   -- from SDL.
--   inRender renderer $ ops
--   G.gegl_exit
--   SDL.destroyWindow window
-- 
-- -- | DEPRECATED!
-- -- Bootstrap a default window.
-- withDefaultWindow :: Monad m => T.Text -> (RenderT m a) -> IO ()
-- withDefaultWindow title ops = withWindow title defaultWindow SDL.defaultRenderer ops

-- | block a thread for a specified amount of time
delaySec
  :: Int -- ^ Number of seconds
  -> IO ()
delaySec dur = SDL.delay (fromIntegral $ dur * 1000)