module Graphics.D3D11Binding.Interface.D3D11DeviceContext where
import Data.Word
import Data.Bits

import Foreign.Storable
import Foreign.Marshal.Alloc
import Foreign.Marshal.Array
import Foreign.Ptr

import Graphics.Win32

import Graphics.D3D11Binding.Enums
import Graphics.D3D11Binding.Types
import Graphics.D3D11Binding.Utils

import Graphics.D3D11Binding.Interface.Unknown
import Graphics.D3D11Binding.Interface.D3D11Buffer
import Graphics.D3D11Binding.Interface.D3D11Resource
import Graphics.D3D11Binding.Interface.D3D11RenderTargetView
import Graphics.D3D11Binding.Interface.D3D11DepthStencilView
import Graphics.D3D11Binding.Interface.D3D11InputLayout
import Graphics.D3D11Binding.Interface.D3D11ClassInstance

import Graphics.D3D11Binding.Shader.D3D11VertexShader
import Graphics.D3D11Binding.Shader.D3D11PixelShader

foreign import stdcall "OMSetRenderTargets" c_omSetRenderTargets
  :: Ptr ID3D11DeviceContext -> Word32 -> Ptr (Ptr ID3D11RenderTargetView) -> Ptr ID3D11DepthStencilView -> IO ()

foreign import stdcall "RSSetViewports" c_rsSetViewports
  :: Ptr ID3D11DeviceContext -> Word32 -> Ptr D3D11Viewport -> IO ()

foreign import stdcall "ClearRenderTargetView" c_clearRenderTargetView
  :: Ptr ID3D11DeviceContext -> Ptr ID3D11RenderTargetView -> Ptr Float -> IO ()

foreign import stdcall "ClearDepthStencilView" c_clearDepthStencilView
  :: Ptr ID3D11DeviceContext -> Ptr ID3D11DepthStencilView -> Word32 -> Float -> Word8 -> IO ()

foreign import stdcall "IASetInputLayout" c_iaSetInputLayout
  :: Ptr ID3D11DeviceContext -> Ptr ID3D11InputLayout -> IO ()
  
foreign import stdcall "IASetVertexBuffers" c_iaSetVertexBuffers
  :: Ptr ID3D11DeviceContext -> Word32 -> Word32 -> Ptr (Ptr ID3D11Buffer) -> Ptr Word32 -> Ptr Word32 -> IO ()

foreign import stdcall "IASetIndexBuffer" c_iaSetIndexBuffer
  :: Ptr ID3D11DeviceContext -> Ptr ID3D11Buffer -> Word32 -> Word32 -> IO ()

foreign import stdcall "IASetPrimitiveTopology" c_iaSetPrimitiveTopology
  :: Ptr ID3D11DeviceContext -> Word32 -> IO ()
  
foreign import stdcall "VSSetShader" c_vsSetShader
  :: Ptr ID3D11DeviceContext -> Ptr ID3D11VertexShader -> Ptr (Ptr ID3D11ClassInstance) -> Word32 -> IO () 
  
foreign import stdcall "PSSetShader" c_psSetShader
  :: Ptr ID3D11DeviceContext -> Ptr ID3D11PixelShader -> Ptr (Ptr ID3D11ClassInstance) -> Word32 -> IO () 

foreign import stdcall "Draw" c_draw
  :: Ptr ID3D11DeviceContext -> Word32 -> Word32 -> IO ()
  
foreign import stdcall "UpdateSubresource" c_updateSubresource
  :: Ptr ID3D11DeviceContext -> Ptr ID3D11Resource -> Word32 -> Ptr D3D11Box -> Ptr () -> Word32 -> Word32 -> IO ()

foreign import stdcall "VSSetConstantBuffers" c_vsSetConstantBuffers
  :: Ptr ID3D11DeviceContext -> Word32 -> Word32 -> Ptr (Ptr ID3D11Buffer) -> IO ()

foreign import stdcall "DrawIndexed" c_drawIndexed
  :: Ptr ID3D11DeviceContext -> Word32 -> Word32 -> Word32 -> IO ()

class (UnknownInterface interface) => D3D11DeviceContextInterface interface where
  omSetRenderTargets :: Ptr interface -> [Ptr ID3D11RenderTargetView] -> Ptr ID3D11DepthStencilView -> IO ()
  omSetRenderTargets ptr renderTargetViews depthStencilView = alloca $ \pRenderTargetViews -> do
    pokeArray pRenderTargetViews renderTargetViews
    c_omSetRenderTargets (castPtr ptr) (fromIntegral $ length renderTargetViews) pRenderTargetViews depthStencilView
  
  rsSetViewports :: Ptr interface -> [D3D11Viewport] -> IO ()
  rsSetViewports ptr viewports = alloca $ \pViewports -> do
    pokeArray pViewports viewports
    c_rsSetViewports (castPtr ptr) (fromIntegral $ length viewports) pViewports
  
  iaSetInputLayout :: Ptr interface -> Ptr ID3D11InputLayout -> IO ()
  iaSetInputLayout ptr inputLayout = c_iaSetInputLayout (castPtr ptr) inputLayout
  
  iaSetVertexBuffers :: Ptr interface -> Word32 -> [(Ptr ID3D11Buffer, Word32, Word32)] -> IO ()
  iaSetVertexBuffers ptr startSlot bufferData = do
    let buffer = map first bufferData
    let stride = map second bufferData
    let offset = map third bufferData
    alloca $ \pBuffer -> alloca $ \pStride -> alloca $ \pOffset -> do
      pokeArray pBuffer buffer
      pokeArray pStride stride
      pokeArray pOffset offset
      c_iaSetVertexBuffers (castPtr ptr) startSlot (fromIntegral $ length bufferData) pBuffer pStride pOffset
    where first (a,_,_) = a
          second (_,b,_) = b
          third (_,_,c) = c
  
  iaSetIndexBuffer :: Ptr interface -> Ptr ID3D11Buffer -> DxgiFormat -> Word32 -> IO ()
  iaSetIndexBuffer ptr buffer format offset = c_iaSetIndexBuffer (castPtr ptr) buffer (fromIntegral $ fromEnum format) offset
  
  iaSetPrimitiveTopology :: Ptr interface -> D3D11PrimitiveTopology -> IO ()
  iaSetPrimitiveTopology ptr topology = c_iaSetPrimitiveTopology (castPtr ptr) (fromIntegral $ fromEnum topology)
  
  clearRenderTargetView :: Ptr interface -> Ptr ID3D11RenderTargetView -> Color -> IO ()
  clearRenderTargetView ptr renderTargetView color = alloca $ \pColor -> do
    poke pColor color
    c_clearRenderTargetView (castPtr ptr) renderTargetView (castPtr pColor)
  
  clearDepthStencilView :: Ptr interface -> Ptr ID3D11DepthStencilView -> [D3D11ClearFlag] -> Float -> Word8 -> IO ()
  clearDepthStencilView ptr depthStencilView flags depth stencil = do
    let sumFlag = fromIntegral $ foldl (\acc x -> acc .|. (fromEnum x)) 0 flags
    c_clearDepthStencilView (castPtr ptr) depthStencilView sumFlag depth stencil
  
  clearState :: Ptr interface -> IO ()
  clearState ptr = c_clearState (castPtr ptr)
  
  vsSetShader :: Ptr interface -> Ptr ID3D11VertexShader -> [Ptr ID3D11ClassInstance] -> IO ()
  vsSetShader ptr vertexShader classInstances = maybePokeArray classInstances $ \pClassInstances -> do
    let classInstanceNum = fromIntegral $ length classInstances
    c_vsSetShader (castPtr ptr) vertexShader pClassInstances classInstanceNum
  
  vsSetConstantBuffers :: Ptr interface -> Word32 -> [Ptr ID3D11Buffer] -> IO ()
  vsSetConstantBuffers ptr startSlot buffers = alloca $ \pBuffer -> do
    pokeArray pBuffer buffers
    c_vsSetConstantBuffers (castPtr ptr) startSlot (fromIntegral $ length buffers) pBuffer
  
  psSetShader :: Ptr interface -> Ptr ID3D11PixelShader -> [Ptr ID3D11ClassInstance] -> IO ()
  psSetShader ptr pixelShader classInstances = maybePokeArray classInstances $ \pClassInstances -> do
    let classInstanceNum = fromIntegral $ length classInstances
    c_psSetShader (castPtr ptr) pixelShader pClassInstances classInstanceNum
  
  draw :: Ptr interface -> Word32 -> Word32 -> IO ()
  draw ptr vertexCount startVertexLocation = c_draw (castPtr ptr) vertexCount startVertexLocation
  
  drawIndexed :: Ptr interface -> Word32 -> Word32 -> Word32 -> IO ()
  drawIndexed ptr indexCount startIndexLocation baseVertexLocation =
    c_drawIndexed (castPtr ptr) indexCount startIndexLocation baseVertexLocation
  
  updateSubresource :: 
    (D3D11ResourceInterface resource, Storable store) => 
    Ptr interface -> Ptr resource -> Word32 -> Maybe D3D11Box -> store -> Word32 -> Word32 -> IO ()
  updateSubresource ptr dstResource dstSubresource dstBox srcData srcRowPitch srcDepthPitch = 
    maybePoke dstBox $ \pDstBox -> alloca $ \pSrcData -> do
      poke pSrcData srcData
      c_updateSubresource (castPtr ptr) (castPtr dstResource) dstSubresource pDstBox (castPtr pSrcData) srcRowPitch srcDepthPitch

data ID3D11DeviceContext = ID3D11DeviceContext

foreign import stdcall "ClearState" c_clearState
 :: Ptr ID3D11DeviceContext -> IO ()

instance UnknownInterface ID3D11DeviceContext where
  use i f = do
    res <- f i
    clearState i
    release i
    return res
instance D3D11DeviceContextInterface ID3D11DeviceContext