/*
 *  Created on: Oct 3, 2019

	Copyright 2019 flyinghead

	This file is part of Flycast.

    Flycast is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 2 of the License, or
    (at your option) any later version.

    Flycast is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with Flycast.  If not, see <https://www.gnu.org/licenses/>.
*/
#include <math.h>
#include "texture.h"
#include "utils.h"

void setImageLayout(vk::CommandBuffer const& commandBuffer, vk::Image image, vk::Format format, u32 mipmapLevels, vk::ImageLayout oldImageLayout, vk::ImageLayout newImageLayout)
{
	vk::AccessFlags sourceAccessMask;
	switch (oldImageLayout)
	{
	case vk::ImageLayout::eTransferDstOptimal:
		sourceAccessMask = vk::AccessFlagBits::eTransferWrite;
		break;
	case vk::ImageLayout::ePreinitialized:
		sourceAccessMask = vk::AccessFlagBits::eHostWrite;
		break;
	case vk::ImageLayout::eGeneral:     // sourceAccessMask is empty
	case vk::ImageLayout::eUndefined:
		break;
	case vk::ImageLayout::eShaderReadOnlyOptimal:
		sourceAccessMask = vk::AccessFlagBits::eShaderRead;
		break;
	default:
		verify(false);
		break;
	}

	vk::PipelineStageFlags sourceStage;
	switch (oldImageLayout)
	{
	case vk::ImageLayout::eGeneral:
	case vk::ImageLayout::ePreinitialized:
		sourceStage = vk::PipelineStageFlagBits::eHost;
		break;
	case vk::ImageLayout::eTransferDstOptimal:
		sourceStage = vk::PipelineStageFlagBits::eTransfer;
		break;
	case vk::ImageLayout::eUndefined:
		sourceStage = vk::PipelineStageFlagBits::eTopOfPipe;
		break;
	case vk::ImageLayout::eShaderReadOnlyOptimal:
		sourceStage = vk::PipelineStageFlagBits::eFragmentShader;
		break;
	default:
		verify(false);
		break;
	}

	vk::AccessFlags destinationAccessMask;
	switch (newImageLayout)
	{
	case vk::ImageLayout::eColorAttachmentOptimal:
		destinationAccessMask = vk::AccessFlagBits::eColorAttachmentWrite;
		break;
	case vk::ImageLayout::eDepthStencilAttachmentOptimal:
		destinationAccessMask = vk::AccessFlagBits::eDepthStencilAttachmentRead | vk::AccessFlagBits::eDepthStencilAttachmentWrite;
		break;
	case vk::ImageLayout::eGeneral:   // empty destinationAccessMask
	break;
	case vk::ImageLayout::eShaderReadOnlyOptimal:
		destinationAccessMask = vk::AccessFlagBits::eShaderRead;
		break;
	case vk::ImageLayout::eTransferSrcOptimal:
		destinationAccessMask = vk::AccessFlagBits::eTransferRead;
		break;
	case vk::ImageLayout::eTransferDstOptimal:
		destinationAccessMask = vk::AccessFlagBits::eTransferWrite;
		break;
	default:
		verify(false);
		break;
	}

	vk::PipelineStageFlags destinationStage;
	switch (newImageLayout)
	{
	case vk::ImageLayout::eColorAttachmentOptimal:
		destinationStage = vk::PipelineStageFlagBits::eColorAttachmentOutput;
		break;
	case vk::ImageLayout::eDepthStencilAttachmentOptimal:
		destinationStage = vk::PipelineStageFlagBits::eEarlyFragmentTests;
		break;
	case vk::ImageLayout::eGeneral:
		destinationStage = vk::PipelineStageFlagBits::eHost;
		break;
	case vk::ImageLayout::eShaderReadOnlyOptimal:
		destinationStage = vk::PipelineStageFlagBits::eFragmentShader;
		break;
	case vk::ImageLayout::eTransferDstOptimal:
	case vk::ImageLayout::eTransferSrcOptimal:
		destinationStage = vk::PipelineStageFlagBits::eTransfer;
		break;
	default:
		verify(false);
		break;
	}

	vk::ImageAspectFlags aspectMask;
	if (newImageLayout == vk::ImageLayout::eDepthStencilAttachmentOptimal)
	{
		aspectMask = vk::ImageAspectFlagBits::eDepth;
		if (format == vk::Format::eD32SfloatS8Uint || format == vk::Format::eD24UnormS8Uint || format == vk::Format::eD16UnormS8Uint)
		{
			aspectMask |= vk::ImageAspectFlagBits::eStencil;
		}
	}
	else
	{
		aspectMask = vk::ImageAspectFlagBits::eColor;
	}

	vk::ImageSubresourceRange imageSubresourceRange(aspectMask, 0, mipmapLevels, 0, 1);
	vk::ImageMemoryBarrier imageMemoryBarrier(sourceAccessMask, destinationAccessMask, oldImageLayout, newImageLayout, VK_QUEUE_FAMILY_IGNORED, VK_QUEUE_FAMILY_IGNORED, image, imageSubresourceRange);
	commandBuffer.pipelineBarrier(sourceStage, destinationStage, {}, nullptr, nullptr, imageMemoryBarrier);
}

void Texture::UploadToGPU(int width, int height, u8 *data)
{
	vk::Format format;
	u32 dataSize = width * height * 2;
	switch (tex_type)
	{
	case TextureType::_5551:
		format = vk::Format::eR5G5B5A1UnormPack16;
		break;
	case TextureType::_565:
		format = vk::Format::eR5G6B5UnormPack16;
		break;
	case TextureType::_4444:
		format = vk::Format::eR4G4B4A4UnormPack16;
		break;
	case TextureType::_8888:
		format = vk::Format::eR8G8B8A8Unorm;
		dataSize *= 2;
		break;
	case TextureType::_8:
		format = vk::Format::eR8Unorm;
		dataSize /= 2;
		break;
	}
	bool isNew = true;
	if (width != extent.width || height != extent.height || format != this->format)
		Init(width, height, format);
	else
		isNew = false;
	SetImage(dataSize, data, isNew);
}

void Texture::Init(u32 width, u32 height, vk::Format format)
{
	this->extent = vk::Extent2D(width, height);
	this->format = format;
	mipmapLevels = 1;
	if (tcw.MipMapped)
		mipmapLevels += floor(log2(std::max(width, height)));

	vk::FormatProperties formatProperties = physicalDevice.getFormatProperties(format);

	vk::FormatFeatureFlags formatFeatureFlags = vk::FormatFeatureFlagBits::eSampledImage;
	// Forcing staging since it fixes texture glitches
	needsStaging = (formatProperties.optimalTilingFeatures & formatFeatureFlags) == formatFeatureFlags;
	vk::ImageTiling imageTiling;
	vk::ImageLayout initialLayout;
	vk::MemoryPropertyFlags requirements;
	vk::ImageUsageFlags usageFlags = vk::ImageUsageFlagBits::eSampled;
	if (needsStaging)
	{
		if (allocator)
			stagingBufferData = std::unique_ptr<BufferData>(new BufferData(physicalDevice, device, extent.width * extent.height * 4, vk::BufferUsageFlagBits::eTransferSrc, allocator));
		else
			stagingBufferData = std::unique_ptr<BufferData>(new BufferData(physicalDevice, device, extent.width * extent.height * 4, vk::BufferUsageFlagBits::eTransferSrc));
		imageTiling = vk::ImageTiling::eOptimal;
		usageFlags |= vk::ImageUsageFlagBits::eTransferDst;
		initialLayout = vk::ImageLayout::eUndefined;
		requirements = vk::MemoryPropertyFlagBits::eDeviceLocal;
	}
	else
	{
		verify((formatProperties.linearTilingFeatures & formatFeatureFlags) == formatFeatureFlags);
		imageTiling = vk::ImageTiling::eLinear;
		initialLayout = vk::ImageLayout::ePreinitialized;
		requirements = vk::MemoryPropertyFlagBits::eHostCoherent | vk::MemoryPropertyFlagBits::eHostVisible;
	}
	if (mipmapLevels > 1)
		usageFlags |= vk::ImageUsageFlagBits::eTransferSrc | vk::ImageUsageFlagBits::eTransferDst;
	CreateImage(imageTiling, usageFlags, initialLayout, requirements, vk::ImageAspectFlagBits::eColor);
}

void Texture::CreateImage(vk::ImageTiling tiling, vk::ImageUsageFlags usage, vk::ImageLayout initialLayout,
		vk::MemoryPropertyFlags memoryProperties, vk::ImageAspectFlags aspectMask)
{
	vk::ImageCreateInfo imageCreateInfo(vk::ImageCreateFlags(), vk::ImageType::e2D, format, vk::Extent3D(extent, 1), mipmapLevels, 1,
										vk::SampleCountFlagBits::e1, tiling, usage,
										vk::SharingMode::eExclusive, 0, nullptr, initialLayout);
	image = device.createImageUnique(imageCreateInfo);

	vk::MemoryRequirements memReq = device.getImageMemoryRequirements(image.get());
	memoryType = findMemoryType(physicalDevice.getMemoryProperties(), memReq.memoryTypeBits, memoryProperties);
	if (allocator)
	{
		if (sharedDeviceMemory)
			allocator->Free(memoryOffset, memoryType, sharedDeviceMemory);
		memoryOffset = allocator->Allocate(memReq.size, memReq.alignment, memoryType, sharedDeviceMemory);
	}
	else
	{
		deviceMemory = device.allocateMemoryUnique(vk::MemoryAllocateInfo(memReq.size, memoryType));
		memoryOffset = 0;
	}

	device.bindImageMemory(image.get(), allocator ? sharedDeviceMemory : *deviceMemory, memoryOffset);

	vk::ImageViewCreateInfo imageViewCreateInfo(vk::ImageViewCreateFlags(), image.get(), vk::ImageViewType::e2D, format, vk::ComponentMapping(),
			vk::ImageSubresourceRange(aspectMask, 0, mipmapLevels, 0, 1));
	imageView = device.createImageViewUnique(imageViewCreateInfo);
}

void Texture::SetImage(u32 srcSize, void *srcData, bool isNew)
{
	verify((bool)commandBuffer);
	commandBuffer.begin(vk::CommandBufferBeginInfo(vk::CommandBufferUsageFlagBits::eOneTimeSubmit));

	if (!isNew && !needsStaging)
		setImageLayout(commandBuffer, image.get(), format, mipmapLevels, vk::ImageLayout::eShaderReadOnlyOptimal, vk::ImageLayout::eGeneral);

	vk::DeviceSize size = needsStaging
			? device.getBufferMemoryRequirements(stagingBufferData->buffer.get()).size
					: device.getImageMemoryRequirements(image.get()).size;
	void* data = needsStaging
			? stagingBufferData->MapMemory()
					: device.mapMemory(allocator ? sharedDeviceMemory : *deviceMemory, memoryOffset, size);
	memcpy(data, srcData, srcSize);

	if (needsStaging)
	{
		stagingBufferData->UnmapMemory();
		// Since we're going to blit to the texture image, set its layout to eTransferDstOptimal
		setImageLayout(commandBuffer, image.get(), format, mipmapLevels, isNew ? vk::ImageLayout::eUndefined : vk::ImageLayout::eShaderReadOnlyOptimal,
				vk::ImageLayout::eTransferDstOptimal);
		vk::BufferImageCopy copyRegion(0, extent.width, extent.height, vk::ImageSubresourceLayers(vk::ImageAspectFlagBits::eColor, 0, 0, 1), vk::Offset3D(0, 0, 0), vk::Extent3D(extent, 1));
		commandBuffer.copyBufferToImage(stagingBufferData->buffer.get(), image.get(), vk::ImageLayout::eTransferDstOptimal, copyRegion);
		if (mipmapLevels > 1)
			GenerateMipmaps();
		else
			// Set the layout for the texture image from eTransferDstOptimal to SHADER_READ_ONLY
			setImageLayout(commandBuffer, image.get(), format, mipmapLevels, vk::ImageLayout::eTransferDstOptimal, vk::ImageLayout::eShaderReadOnlyOptimal);
	}
	else
	{
		device.unmapMemory(allocator ? sharedDeviceMemory : *deviceMemory);
		if (mipmapLevels > 1)
			GenerateMipmaps();
		else
			// If we can use the linear tiled image as a texture, just do it
			setImageLayout(commandBuffer, image.get(), format, mipmapLevels, vk::ImageLayout::ePreinitialized, vk::ImageLayout::eShaderReadOnlyOptimal);
	}
	commandBuffer.end();

	VulkanContext::Instance()->GetGraphicsQueue().submit(vk::SubmitInfo(0, nullptr, nullptr, 1, &commandBuffer), nullptr);
}

void Texture::GenerateMipmaps()
{
	u32 mipWidth = extent.width;
	u32 mipHeight = extent.height;
	vk::ImageMemoryBarrier barrier(vk::AccessFlagBits::eTransferWrite, vk::AccessFlagBits::eTransferRead,
			vk::ImageLayout::eTransferDstOptimal, vk::ImageLayout::eTransferSrcOptimal, VK_QUEUE_FAMILY_IGNORED, VK_QUEUE_FAMILY_IGNORED,
			*image, vk::ImageSubresourceRange(vk::ImageAspectFlagBits::eColor, 0, 1, 0, 1));

	for (int i = 1; i < mipmapLevels; i++)
	{
		// Transition previous mipmap level from dst optimal/preinit to src optimal
		barrier.subresourceRange.baseMipLevel = i - 1;
		if (i == 1 && !needsStaging)
		{
			barrier.oldLayout = vk::ImageLayout::ePreinitialized;
			barrier.srcAccessMask = vk::AccessFlagBits::eHostWrite;
		}
		else
		{
			barrier.oldLayout = vk::ImageLayout::eTransferDstOptimal;
			barrier.srcAccessMask = vk::AccessFlagBits::eTransferWrite;
		}
		barrier.newLayout = vk::ImageLayout::eTransferSrcOptimal;
		barrier.dstAccessMask = vk::AccessFlagBits::eTransferRead;
		commandBuffer.pipelineBarrier(vk::PipelineStageFlagBits::eTransfer, vk::PipelineStageFlagBits::eTransfer, {}, nullptr, nullptr, barrier);

		// Blit previous mipmap level on current
		vk::ImageBlit blit(vk::ImageSubresourceLayers(vk::ImageAspectFlagBits::eColor, i - 1, 0, 1),
				 { { vk::Offset3D(0, 0, 0), vk::Offset3D(mipWidth, mipHeight, 1) } },
				 vk::ImageSubresourceLayers(vk::ImageAspectFlagBits::eColor, i, 0, 1),
				 { { vk::Offset3D(0, 0, 0), vk::Offset3D(std::max(mipWidth / 2, 1u), std::max(mipHeight / 2, 1u), 1) } });
		commandBuffer.blitImage(*image, vk::ImageLayout::eTransferSrcOptimal, *image, vk::ImageLayout::eTransferDstOptimal, 1, &blit, vk::Filter::eLinear);

		// Transition previous mipmap level from src optimal to shader read-only optimal
		barrier.oldLayout = vk::ImageLayout::eTransferSrcOptimal;
		barrier.newLayout = vk::ImageLayout::eShaderReadOnlyOptimal;
		barrier.srcAccessMask = vk::AccessFlagBits::eTransferRead;
		barrier.dstAccessMask = vk::AccessFlagBits::eShaderRead;
		commandBuffer.pipelineBarrier(vk::PipelineStageFlagBits::eTransfer, vk::PipelineStageFlagBits::eFragmentShader, {}, nullptr, nullptr, barrier);

		mipWidth = std::max(mipWidth / 2, 1u);
		mipHeight = std::max(mipHeight / 2, 1u);
	}
	// Transition last mipmap level from dst optimal to shader read-only optimal
	barrier.subresourceRange.baseMipLevel = mipmapLevels - 1;
	barrier.oldLayout = vk::ImageLayout::eTransferDstOptimal;
	barrier.newLayout = vk::ImageLayout::eShaderReadOnlyOptimal;
	barrier.srcAccessMask = vk::AccessFlagBits::eTransferWrite;
	barrier.dstAccessMask = vk::AccessFlagBits::eShaderRead;
	commandBuffer.pipelineBarrier(vk::PipelineStageFlagBits::eTransfer, vk::PipelineStageFlagBits::eFragmentShader, {}, nullptr, nullptr, barrier);
}

void FramebufferAttachment::Init(u32 width, u32 height, vk::Format format, vk::ImageUsageFlags additionalUsageFlags)
{
	this->format = format;
	this->extent = vk::Extent2D { width, height };
	bool depth = format == vk::Format::eD32SfloatS8Uint || format == vk::Format::eD24UnormS8Uint || format == vk::Format::eD16UnormS8Uint;

	vk::ImageUsageFlags usage;
	if (depth)
	{
		usage = vk::ImageUsageFlagBits::eDepthStencilAttachment;
	}
	else
	{
		if (!(additionalUsageFlags & vk::ImageUsageFlagBits::eStorage))
			usage = vk::ImageUsageFlagBits::eColorAttachment;
		if (!(additionalUsageFlags & (vk::ImageUsageFlagBits::eInputAttachment | vk::ImageUsageFlagBits::eStorage)))
		{
			if (settings.rend.RenderToTextureBuffer) // FIXME incorrect for OIT
			{
				usage |= vk::ImageUsageFlagBits::eTransferSrc;
				stagingBufferData = std::unique_ptr<BufferData>(new BufferData(VulkanContext::Instance()->GetPhysicalDevice(), VulkanContext::Instance()->GetDevice(),
						width * height * 4, vk::BufferUsageFlagBits::eTransferSrc | vk::BufferUsageFlagBits::eTransferDst, allocator));
			}
			else
			{
				usage |= vk::ImageUsageFlagBits::eSampled;
			}
		}
	}
	usage |= additionalUsageFlags;
	vk::ImageCreateInfo imageCreateInfo(vk::ImageCreateFlags(), vk::ImageType::e2D, format, vk::Extent3D(extent, 1), 1, 1, vk::SampleCountFlagBits::e1,
			(additionalUsageFlags & vk::ImageUsageFlagBits::eStorage) ? vk::ImageTiling::eLinear : vk::ImageTiling::eOptimal,
			usage,
			vk::SharingMode::eExclusive, 0, nullptr, vk::ImageLayout::eUndefined);
	image = device.createImageUnique(imageCreateInfo);
	vk::MemoryRequirements memReq = device.getImageMemoryRequirements(image.get());

	if (allocator)
	{
		if (sharedDeviceMemory)
			allocator->Free(memoryOffset, memoryType, sharedDeviceMemory);
	}
	memoryType = findMemoryType(physicalDevice.getMemoryProperties(), memReq.memoryTypeBits, vk::MemoryPropertyFlagBits::eDeviceLocal);
	if (allocator)
	{
		memoryOffset = allocator->Allocate(memReq.size, memReq.alignment, memoryType, sharedDeviceMemory);
	}
	else
	{
		deviceMemory = device.allocateMemoryUnique(vk::MemoryAllocateInfo(memReq.size, memoryType));
		memoryOffset = 0;
	}
	device.bindImageMemory(image.get(), allocator ? sharedDeviceMemory : *deviceMemory, memoryOffset);

	vk::ImageViewCreateInfo imageViewCreateInfo(vk::ImageViewCreateFlags(), image.get(), vk::ImageViewType::e2D,
			format, vk::ComponentMapping(),	vk::ImageSubresourceRange(depth ? vk::ImageAspectFlagBits::eDepth : vk::ImageAspectFlagBits::eColor, 0, 1, 0, 1));
	imageView = device.createImageViewUnique(imageViewCreateInfo);

	if (depth && (additionalUsageFlags & vk::ImageUsageFlagBits::eInputAttachment))
	{
		// Also create an imageView for the stencil
		imageViewCreateInfo.subresourceRange = vk::ImageSubresourceRange(vk::ImageAspectFlagBits::eStencil, 0, 1, 0, 1);
		stencilView = device.createImageViewUnique(imageViewCreateInfo);
	}
}