//! Vulkan RenderPass/Framebuffer

use vk::*;
use {VkHandle, DeviceChild};
#[cfg(feature = "Implements")] use VkResultHandler;
use std::borrow::{Borrow, BorrowMut};
use std::mem::transmute;
use ImageLayout;

/// Opaque handle to a render pass object
pub struct RenderPass(VkRenderPass, ::Device);
/// Opaque handle to a framebuffer object
pub struct Framebuffer(VkFramebuffer, ::Device, Vec<::ImageView>, ::Extent2D);

#[cfg(feature = "Implements")] DeviceChildCommonDrop!{
	for RenderPass[vkDestroyRenderPass], Framebuffer[vkDestroyFramebuffer]
}
impl VkHandle for RenderPass { type Handle = VkRenderPass; fn native_ptr(&self) -> VkRenderPass { self.0 } }
impl VkHandle for Framebuffer { type Handle = VkFramebuffer; fn native_ptr(&self) -> VkFramebuffer { self.0 } }
impl DeviceChild for RenderPass { fn device(&self) -> &::Device { &self.1 } }
impl DeviceChild for Framebuffer { fn device(&self) -> &::Device { &self.1 } }

/// Builder structure to construct the `VkAttachmentDescription`
pub struct AttachmentDescription(VkAttachmentDescription);
impl AttachmentDescription
{
	pub fn new(format: VkFormat, init_layout: ImageLayout, fin_layout: ImageLayout) -> Self
	{
		AttachmentDescription(VkAttachmentDescription
		{
			format, samples: 1,
			loadOp: VK_ATTACHMENT_LOAD_OP_DONT_CARE, storeOp: VK_ATTACHMENT_STORE_OP_DONT_CARE,
			stencilLoadOp: VK_ATTACHMENT_LOAD_OP_DONT_CARE, stencilStoreOp: VK_ATTACHMENT_STORE_OP_DONT_CARE,
			initialLayout: init_layout as _, finalLayout: fin_layout as _, flags: 0
		})
	}
	pub fn format(mut self, fmt: VkFormat) -> Self { self.0.format = fmt; self }
	pub fn load_op(mut self, op: LoadOp) -> Self { self.0.loadOp = op as _; self }
	pub fn store_op(mut self, op: StoreOp) -> Self { self.0.storeOp = op as _; self }
	pub fn stencil_load_op(mut self, op: LoadOp) -> Self { self.0.stencilLoadOp = op as _; self }
	pub fn stencil_store_op(mut self, op: StoreOp) -> Self { self.0.stencilStoreOp = op as _; self }
	pub fn init_layout(mut self, layout: ImageLayout) -> Self { self.0.initialLayout = layout as _; self }
	pub fn fin_layout(mut self, layout: ImageLayout) -> Self { self.0.finalLayout = layout as _; self }
	pub fn may_alias_attachment(mut self) -> Self { self.0.flags |= VK_ATTACHMENT_DESCRIPTION_MAY_ALIAS_BIT; self }
	pub fn no_alias_attachment(mut self) -> Self { self.0.flags &= !VK_ATTACHMENT_DESCRIPTION_MAY_ALIAS_BIT; self }
	pub fn samples(mut self, count: u32) -> Self { self.0.samples = count; return self; }

	pub fn mod_format(&mut self, fmt: VkFormat) -> &mut Self { self.0.format = fmt; self }
	pub fn mod_load_op(&mut self, op: LoadOp) -> &mut Self { self.0.loadOp = op as _; self }
	pub fn mod_store_op(&mut self, op: StoreOp) -> &mut Self { self.0.storeOp = op as _; self }
	pub fn mod_stencil_load_op(&mut self, op: LoadOp) -> &mut Self { self.0.stencilLoadOp = op as _; self }
	pub fn mod_stencil_store_op(&mut self, op: StoreOp) -> &mut Self { self.0.stencilStoreOp = op as _; self }
	pub fn mod_init_layout(&mut self, layout: ImageLayout) -> &mut Self { self.0.initialLayout = layout as _; self }
	pub fn mod_fin_layout(&mut self, layout: ImageLayout) -> &mut Self { self.0.finalLayout = layout as _; self }
	pub fn mod_may_alias_attachment(&mut self) -> &mut Self { self.0.flags |= VK_ATTACHMENT_DESCRIPTION_MAY_ALIAS_BIT; self }
	pub fn mod_no_alias_attachment(&mut self) -> &mut Self { self.0.flags &= !VK_ATTACHMENT_DESCRIPTION_MAY_ALIAS_BIT; self }
	pub fn mod_samples(&mut self, count: u32) -> &mut Self { self.0.samples = count; return self; }
}
impl Borrow<AttachmentDescription> for VkAttachmentDescription
{
	fn borrow(&self) -> &AttachmentDescription { unsafe { transmute(self) } }
}
impl BorrowMut<AttachmentDescription> for VkAttachmentDescription
{
	fn borrow_mut(&mut self) -> &mut AttachmentDescription { unsafe { transmute(self) } }
}
#[repr(C)] #[derive(Debug, Clone, Copy, PartialEq, Eq)] pub enum LoadOp
{
	/// The previous contents of the image within the render area will be preserved.
	/// 
	/// ## Used access types
	/// 
	/// This operation uses the "Read" access
	Load = VK_ATTACHMENT_LOAD_OP_LOAD as _,
	/// The contents within the render area will be cleared to a uniform value, which is
	/// specified when a render pass instance is begun.
	/// 
	/// ## Used access types
	/// 
	/// This operation uses the "Write" access
	Clear = VK_ATTACHMENT_LOAD_OP_CLEAR as _,
	/// The previous contents within the area need not be preserved;
	/// the contents of the attachment will be undefined inside the render area.
	/// 
	/// ## Used access types
	/// 
	/// This operation uses the "Write" access
	DontCare = VK_ATTACHMENT_LOAD_OP_DONT_CARE as _
}
/// Possible argument values of `AttachmentDescription::store_op` and `stencil_store_op`,
/// specifying how the contents of the attachment are treated.
/// 
/// ## Used access types
/// 
/// Both items use the "Write" access
#[repr(C)] #[derive(Debug, Clone, Copy, PartialEq, Eq)] pub enum StoreOp
{
	/// The contents generated during the render pass and within the render area are written to memory.
	Store = VK_ATTACHMENT_STORE_OP_STORE as _,
	/// The contents within the render area are not needed after rendering, and *may* be discarded;
	/// the contents of the attachment will be undefined inside the render area.
	DontCare = VK_ATTACHMENT_STORE_OP_DONT_CARE as _
}
/// Builder structure to construct the `VkSubpassDescription`
/// 
/// ## The `layout` parameter of each attachment
/// 
/// The `layout` parameter describes what layout the attachment will be in during the subpass.
/// 
/// ## How *input attachments* work
/// 
/// * Each element of the array corresponds to an input attachment unit number in the shader.  
///   * i. e. if the shader declares an input variable `layout(input_attachment_index=X, set=Y, binding=Z)`
///     then it uses the attachment provided in `input_attachments[X]`.  
/// * Input attachments *must* also be bound to the pipeline with a descriptor set, with the input attachment descriptor
///   written in the location (set=Y, binding=Z).
/// * Fragment shaders *can* use subpass input variables to access the contents of an input attachment at the fragment's
///   (x, y, layer) framebuffer coordinates.
/// 
pub struct SubpassDescription
{
	input_attachments: Vec<VkAttachmentReference>, color_attachments: Vec<VkAttachmentReference>,
	resolve_attachments: Vec<VkAttachmentReference>, depth_stencil_attachment: Option<VkAttachmentReference>,
	preserve_attachments: Vec<u32>
}
/// Builder structure to construct the `RenderPass`
pub struct RenderPassBuilder
{
	attachments: Vec<VkAttachmentDescription>, subpasses: Vec<SubpassDescription>,
	dependencies: Vec<VkSubpassDependency>
}
impl RenderPassBuilder
{
	pub fn new() -> Self { RenderPassBuilder { attachments: Vec::new(), subpasses: Vec::new(), dependencies: Vec::new() } }
	pub fn add_attachment(&mut self, desc: AttachmentDescription) -> &mut Self { self.attachments.push(desc.0); self }
	pub fn add_subpass(&mut self, desc: SubpassDescription) -> &mut Self { self.subpasses.push(desc); self }
	pub fn add_dependency(&mut self, desc: VkSubpassDependency) -> &mut Self { self.dependencies.push(desc); self }
	pub fn add_attachments<Collection: IntoIterator<Item = AttachmentDescription>>(&mut self, collection: Collection) -> &mut Self
	{
		for d in collection { self.add_attachment(d); } self
	}
	pub fn add_subpasses<Collection: IntoIterator<Item = SubpassDescription>>(&mut self, collection: Collection) -> &mut Self
	{
		for d in collection { self.add_subpass(d); } self
	}
	pub fn add_dependencies<Collection: IntoIterator<Item = VkSubpassDependency>>(&mut self, collection: Collection) -> &mut Self
	{
		for d in collection { self.add_dependency(d); } self
	}

	pub fn mod_attachment(&mut self, index: usize) -> &mut AttachmentDescription { self.attachments[index].borrow_mut() }
	pub fn mod_subpass(&mut self, index: usize) -> &mut SubpassDescription { &mut self.subpasses[index] }
	pub fn mod_dependency(&mut self, index: usize) -> &mut VkSubpassDependency { &mut self.dependencies[index] }
}
impl SubpassDescription
{
	pub fn new() -> Self
	{
		SubpassDescription
		{
			input_attachments: Vec::new(), color_attachments: Vec::new(), resolve_attachments: Vec::new(), depth_stencil_attachment: None,
			preserve_attachments: Vec::new()
		}
	}
	pub fn add_input(mut self, index: u32, layout: ImageLayout) -> Self
	{
		self.input_attachments.push(VkAttachmentReference { attachment: index, layout: layout as _ }); self
	}
	pub fn add_color_output(mut self, index: u32, layout: ImageLayout, resolve: Option<(u32, ::ImageLayout)>) -> Self
	{
		if let Some((i, l)) = resolve
		{
			while self.resolve_attachments.len() < self.color_attachments.len()
			{
				self.resolve_attachments.push(VkAttachmentReference { attachment: VK_ATTACHMENT_UNUSED, layout: 0 as _ });
			}
			self.resolve_attachments.push(VkAttachmentReference { attachment: i, layout: l as _ });
		}
		self.color_attachments.push(VkAttachmentReference { attachment: index, layout: layout as _ });
		self
	}
	pub fn depth_stencil(mut self, index: u32, layout: ImageLayout) -> Self
	{
		self.depth_stencil_attachment = Some(VkAttachmentReference { attachment: index, layout: layout as _ }); self
	}
	pub fn add_preserve(mut self, index: u32) -> Self
	{
		self.preserve_attachments.push(index); self
	}
	pub fn add_preserves<Collection: IntoIterator<Item = u32>>(mut self, collection: Collection) -> Self
	{
		for i in collection { self.add_preserve_borrow(i); } self
	}

	pub fn add_input_borrow(&mut self, index: u32, layout: ImageLayout) -> &mut Self
	{
		self.input_attachments.push(VkAttachmentReference { attachment: index, layout: layout as _ }); self
	}
	pub fn add_color_output_borrow(&mut self, index: u32, layout: ::ImageLayout, resolve: Option<(u32, ::ImageLayout)>) -> &mut Self
	{
		if let Some((i, l)) = resolve
		{
			while self.resolve_attachments.len() < self.color_attachments.len()
			{
				self.resolve_attachments.push(VkAttachmentReference { attachment: VK_ATTACHMENT_UNUSED, layout: 0 as _ });
			}
			self.resolve_attachments.push(VkAttachmentReference { attachment: i, layout: l as _ });
		}
		self.color_attachments.push(VkAttachmentReference { attachment: index, layout: layout as _ });
		self
	}
	pub fn depth_stencil_borrow(&mut self, index: u32, layout: ::ImageLayout) -> &mut Self
	{
		self.depth_stencil_attachment = Some(VkAttachmentReference { attachment: index, layout: layout as _ }); self
	}
	pub fn add_preserve_borrow(&mut self, index: u32) -> &mut Self
	{
		self.preserve_attachments.push(index); self
	}
	pub fn add_preserves_borrow<Collection: IntoIterator<Item = u32>>(&mut self, collection: Collection) -> &mut Self
	{
		for i in collection { self.add_preserve_borrow(i); } self
	}
}
#[cfg(feature = "Implements")]
impl RenderPassBuilder
{
	/// Create a new render pass object
	/// # Failures
	/// On failure, this command returns
	/// 
	/// * `VK_ERROR_OUT_OF_HOST_MEMORY`
	/// * `VK_ERROR_OUT_OF_DEVICE_MEMORY`
	pub fn create(&self, device: &::Device) -> ::Result<RenderPass>
	{
		let subpasses = self.subpasses.iter().map(|x| VkSubpassDescription
		{
			inputAttachmentCount: x.input_attachments.len() as _, pInputAttachments: x.input_attachments.as_ptr(),
			colorAttachmentCount: x.color_attachments.len() as _, pColorAttachments: x.color_attachments.as_ptr(),
			pResolveAttachments: if x.resolve_attachments.is_empty() { ::std::ptr::null() } else { x.resolve_attachments.as_ptr() },
			pDepthStencilAttachment: if let Some(ref x) = x.depth_stencil_attachment { x } else { ::std::ptr::null() },
			preserveAttachmentCount: x.preserve_attachments.len() as _, pPreserveAttachments: x.preserve_attachments.as_ptr(),
			.. Default::default()
		}).collect::<Vec<_>>();
		let cinfo = VkRenderPassCreateInfo
		{
			attachmentCount: self.attachments.len() as _, pAttachments: self.attachments.as_ptr(),
			subpassCount: subpasses.len() as _, pSubpasses: subpasses.as_ptr(),
			dependencyCount: self.dependencies.len() as _, pDependencies: self.dependencies.as_ptr(),
			.. Default::default()
		};
		let mut h = VK_NULL_HANDLE as _;
		unsafe { vkCreateRenderPass(device.native_ptr(), &cinfo, ::std::ptr::null(), &mut h) }.into_result()
			.map(|_| RenderPass(h, device.clone()))
	}
}
#[cfg(feature = "Implements")]
impl Framebuffer
{
	/// Create a new framebuffer object
	/// # Failures
	/// On failure, this command returns
	/// 
	/// * `VK_ERROR_OUT_OF_HOST_MEMORY`
	/// * `VK_ERROR_OUT_OF_DEVICE_MEMORY`
	pub fn new<Sz: AsRef<::Extent2D>>(mold: &RenderPass, attachment_objects: &[&::ImageView], size: &Sz, layers: u32) -> ::Result<Self>
	{
		let views = attachment_objects.iter().map(|x| x.native_ptr()).collect::<Vec<_>>();
		let cinfo = VkFramebufferCreateInfo
		{
			renderPass: mold.0, attachmentCount: views.len() as _, pAttachments: views.as_ptr(),
			width: size.as_ref().0, height: size.as_ref().1, layers, .. Default::default()
		};
		let mut h = VK_NULL_HANDLE as _;
		unsafe { vkCreateFramebuffer(mold.1.native_ptr(), &cinfo, ::std::ptr::null(), &mut h) }.into_result()
			.map(|_| Framebuffer(h, mold.1.clone(), attachment_objects.iter().map(|&x| x.clone()).collect(), size.as_ref().clone()))
	}
}
impl Framebuffer
{
	pub fn size(&self) -> &::Extent2D { &self.3 }
	pub fn resources(&self) -> &[::ImageView] { &self.2 }
}

#[cfg(feature = "Implements")]
impl RenderPass
{
	/// Returns the granularity for optimal render area
	pub fn optimal_granularity(&self) -> ::Extent2D
	{
		let mut e = ::Extent2D(0, 0);
		unsafe { vkGetRenderAreaGranularity(self.1.native_ptr(), self.0, ::std::mem::transmute(&mut e)) }; e
	}
}