{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE DuplicateRecordFields #-}
{-# LANGUAGE DataKinds #-}
module Main where

import Control.Monad
import Control.Monad.Loops
import Control.Monad.IO.Class
import Control.Monad.Trans.Resource
import Data.Bits
import Data.Word
import qualified SDL hiding (V2)
import qualified Control.Concurrent.STM as STM
import qualified Vulkan as Vk
import qualified Vulkan.Zero as Vk

-- internal imports

import Init

main :: IO ()
main = runResourceT $ do
  (window, inst, surface, swapchain, images) <- initEngine

  SDL.showWindow window

  -- create abort condition for upcoming lop
  quit <- liftIO $ STM.newTMVarIO True

  -- main loop
  liftIO $ whileM_
    (STM.atomically $ STM.readTMVar quit
      )
    ( do
      -- poll events
      evs <- SDL.pollEvents
      -- flip abort condition on window close
      mapM_
        (\e -> case SDL.eventPayload e of
          SDL.WindowClosedEvent _ ->
            void $ STM.atomically $ STM.swapTMVar quit False
          _ -> return ()
          )
        evs
    )

createBufferView
  :: (MonadResource m)
  => Vk.Device
  -> m (ReleaseKey, Vk.BufferView)
createBufferView logicalDevice = do
  let bufferCreateInfo = Vk.zero
        { Vk.size        = 1024
        , Vk.usage       =
          Vk.BUFFER_USAGE_UNIFORM_BUFFER_BIT .|.
          Vk.BUFFER_USAGE_UNIFORM_TEXEL_BUFFER_BIT
        , Vk.sharingMode = Vk.SHARING_MODE_EXCLUSIVE
        }
  buffer <- snd <$> allocate
    (Vk.createBuffer logicalDevice bufferCreateInfo Nothing)
    (\buffer -> do
      print ("destroying buffer" :: String)
      Vk.destroyBuffer logicalDevice buffer Nothing
      )

  let bufferViewCreateInfo = Vk.zero
        { Vk.buffer = buffer
        , Vk.format = Vk.FORMAT_R32G32B32_SFLOAT
        , Vk.offset = 0
        , Vk.range  = Vk.WHOLE_SIZE
        }

  allocate
    (Vk.createBufferView logicalDevice bufferViewCreateInfo Nothing)
    (\bufferView -> do
      print ("destroying bufferView" :: String)
      Vk.destroyBufferView logicalDevice bufferView Nothing
      )

allocateMemory
  :: (MonadResource m)
  => Vk.Device
  -> Vk.Buffer
  -> m (ReleaseKey, Vk.DeviceMemory)
allocateMemory logicalDevice buffer = do
  memoryRequirements <- Vk.getBufferMemoryRequirements logicalDevice buffer

  let memoryAllocateInfo = Vk.zero
        { Vk.allocationSize  = (Vk.size :: Vk.MemoryRequirements -> Word64) memoryRequirements
        , Vk.memoryTypeIndex = error ("createBuffer: TODO: populate memoryTypeIndex!" :: String)
        }

  allocate
    (Vk.allocateMemory logicalDevice memoryAllocateInfo Nothing)
    (\memory -> do
      print ("Freeing memory" :: String)
      Vk.freeMemory logicalDevice memory Nothing
      )