-- | For initialising framebuffers.
module Framebuffer.Setup (
    setupTextureFramebuffer,
    setupFramebufferGivenStencil,
    setupFramebuffer2GivenStencil,
    setupShadowFramebuffer,
) where

import Unsafe.Coerce
import Data.Preload.Render
import GLHelp
import Graphics.GL.Core45
import Graphics.Rendering.OpenGL hiding (Point, imageHeight, scale, translate)

setupTextureFramebuffer ::
    GLsizei ->
    GLsizei ->
    IO (FBO, TO)
{-# INLINE setupTextureFramebuffer #-}
setupTextureFramebuffer x y = do
    --fboName <- genObjectName
    --bindFramebuffer Framebuffer $= fboName
    fboName <- mglCreate glCreateFramebuffers
    --fboTO <- genObjectName
    to <- mglCreate (glCreateTextures GL_TEXTURE_2D)
    --textureBinding Texture2D $= Just fboTO
    --glTexStorage2D GL_TEXTURE_2D 1 GL_RGBA8 x y
    glTextureStorage2D to 1 GL_RGBA8 x y
    glTextureParameteri to GL_TEXTURE_MIN_FILTER (unsafeCoerce GL_NEAREST)
    glTextureParameteri to GL_TEXTURE_MAG_FILTER (unsafeCoerce GL_NEAREST)
    --textureFilter Texture2D $= minMagFilter
    --framebufferTexture2D Framebuffer (ColorAttachment 0) Texture2D fboTO 0
    glNamedFramebufferTexture fboName GL_COLOR_ATTACHMENT0 to 0
    fboStatus <- framebufferStatus Framebuffer
    case fboStatus of
        Complete -> return ()
        _ -> putStrLn $ "Texture framebuffer status: " ++ show fboStatus
    return (FBO fboName, TO to)

setupShadowFramebuffer :: IO (FBO, (TO, TO))
setupShadowFramebuffer = do
    --fboName <- genObjectName
    --bindFramebuffer Framebuffer $= fboName
    fboName <- mglCreate glCreateFramebuffers
    to1 <- mglCreate (glCreateTextures GL_TEXTURE_2D_ARRAY)
    to2 <- mglCreate (glCreateTextures GL_TEXTURE_2D_ARRAY)
    --textureBinding Texture2DArray $= Just toName
    --framebufferRenderbuffer Framebuffer DepthStencilAttachment Renderbuffer rboName
    return (FBO fboName, (TO to1,TO to2))

setupFramebufferGivenStencil ::
    GLuint -> -- RenderbufferObject
    IO (FBO, TO)
{-# INLINE setupFramebufferGivenStencil #-}
setupFramebufferGivenStencil rboName = do
    --fboName <- genObjectName
    --bindFramebuffer Framebuffer $= fboName
    fboName <- mglCreate glCreateFramebuffers
    --toName <- genObjectName
    to1 <- mglCreate (glCreateTextures GL_TEXTURE_2D)
    --framebufferRenderbuffer Framebuffer DepthStencilAttachment Renderbuffer rboName
    glNamedFramebufferRenderbuffer fboName GL_DEPTH_STENCIL_ATTACHMENT GL_RENDERBUFFER rboName
    fboStatus <- framebufferStatus Framebuffer
    case fboStatus of
        Complete -> return ()
        _ -> putStrLn $ "Framebuffer with given stencil status: " ++ show fboStatus
    return (FBO fboName, TO to1)

setupFramebuffer2GivenStencil ::
    GLuint -> -- RenderbufferObject
    IO (FBO, (TO, TO))
setupFramebuffer2GivenStencil rboName = do
    --fboName <- genObjectName
    --bindFramebuffer Framebuffer $= fboName
    fboName <- mglCreate glCreateFramebuffers
--    toName <- genObjectName
--    toName2 <- genObjectName
    to1 <- mglCreate (glCreateTextures GL_TEXTURE_2D)
    to2 <- mglCreate (glCreateTextures GL_TEXTURE_2D)
    --framebufferRenderbuffer Framebuffer DepthStencilAttachment Renderbuffer rboName
    glNamedFramebufferRenderbuffer fboName GL_DEPTH_STENCIL_ATTACHMENT GL_RENDERBUFFER rboName
    fboStatus <- framebufferStatus Framebuffer
    case fboStatus of
        Complete -> return ()
        _ -> putStrLn $ "Framebuffer with given stencil and two texture objects status: " ++ show fboStatus
    return (FBO fboName, (TO to1, TO to2))