#include "VulkanRenderer.h"
#include "VulkanBarrier.h"
#include "VulkanBuffer.h"
#include "VulkanTexture.h"


#include "backends/imgui_impl_vulkan.h"
#include "graphics/2d.h"
#include "lighting/lighting.h"

extern float flFrametime;

namespace graphics::vulkan {

void VulkanRenderer::beginTrackedRenderPass(const PassBeginDesc& desc)
{
	vk::RenderPassBeginInfo rpBegin;
	rpBegin.renderPass = desc.renderPass;
	rpBegin.framebuffer = desc.framebuffer;
	rpBegin.renderArea.offset = vk::Offset2D(0, 0);
	rpBegin.renderArea.extent = desc.extent;
	rpBegin.clearValueCount = static_cast<uint32_t>(desc.clearValues.size);
	rpBegin.pClearValues = desc.clearValues.data;

	m_currentCommandBuffer.beginRenderPass(rpBegin, vk::SubpassContents::eInline);

	m_stateTracker->setRenderPass(desc.renderPass, 0);
	m_stateTracker->setColorAttachmentCount(desc.colorAttachmentCount);
	m_stateTracker->setCurrentSampleCount(desc.sampleCount);
	m_stateTracker->setRenderArea(desc.extent);

	switch (desc.viewport) {
	case PassViewport::FlipY:
		// Negative viewport height for OpenGL-compatible Y-up NDC (VK_KHR_maintenance1)
		m_stateTracker->setViewport(0.0f,
			static_cast<float>(desc.extent.height),
			static_cast<float>(desc.extent.width),
			-static_cast<float>(desc.extent.height));
		break;
	case PassViewport::NoFlip:
		m_stateTracker->setViewport(0.0f, 0.0f,
			static_cast<float>(desc.extent.width),
			static_cast<float>(desc.extent.height));
		break;
	case PassViewport::Keep:
		break;
	}
}

void VulkanRenderer::acquireNextSwapChainImage()
{
	m_frames[m_currentFrame]->waitForFinish();

	// Acquire an image, recreating the swap chain as often as needed (bounded).
	// The frame must never proceed without an acquired image: its image-available
	// semaphore would never be signaled and the submit would deadlock/corrupt.
	constexpr int MAX_ACQUIRE_ATTEMPTS = 5;
	uint32_t imageIndex = 0;
	SwapChainStatus status = SwapChainStatus::eOutOfDate;

	for (int attempt = 0; attempt < MAX_ACQUIRE_ATTEMPTS; ++attempt) {
		// Recreate if flagged (from a previous frame, a failed acquire below, or
		// a suboptimal present). Waits out a minimized window (0x0 extent).
		if (m_swapChainNeedsRecreation) {
			while (!recreateSwapChain()) {
				os_sleep(100);
				SDL_PumpEvents();
			}
		}

		status = m_frames[m_currentFrame]->acquireSwapchainImage(imageIndex);
		if (status != SwapChainStatus::eOutOfDate) {
			break;
		}
		m_swapChainNeedsRecreation = true;
	}

	if (status == SwapChainStatus::eOutOfDate) {
		Error(LOCATION, "Vulkan: failed to acquire a swap chain image after %d recreation attempts!",
			MAX_ACQUIRE_ATTEMPTS);
	}

	if (shouldRecreateSwapChain(status)) {
		m_swapChainNeedsRecreation = true;
	}

	m_currentSwapChainImage = imageIndex;

	// Ensure that this image is no longer in use
	if (m_swapChainImageRenderImage[m_currentSwapChainImage]) {
		m_swapChainImageRenderImage[m_currentSwapChainImage]->waitForFinish();
	}
	// Reserve the image as in use
	m_swapChainImageRenderImage[m_currentSwapChainImage] = m_frames[m_currentFrame].get();
}
void VulkanRenderer::setupFrame()
{
	if (m_frameInProgress) {
		Warning(LOCATION, "VulkanRenderer::setupFrame called while frame already in progress!");
		return;
	}

	// Free completed texture upload command buffers
	Assertion(m_textureManager, "Vulkan TextureManager not initialized in setupFrame!");
	m_textureManager->frameStart();

	// Allocate command buffer for this frame
	vk::CommandBufferAllocateInfo cmdBufferAlloc;
	cmdBufferAlloc.commandPool = m_graphicsCommandPool.get();
	cmdBufferAlloc.level = vk::CommandBufferLevel::ePrimary;
	cmdBufferAlloc.commandBufferCount = 1;

	auto cmdBufs = m_device->allocateCommandBuffers(cmdBufferAlloc);
	m_currentCommandBuffers.assign(cmdBufs.begin(), cmdBufs.end());
	m_currentCommandBuffer = m_currentCommandBuffers.front();

	// Begin command buffer
	vk::CommandBufferBeginInfo beginInfo;
	beginInfo.flags |= vk::CommandBufferUsageFlagBits::eOneTimeSubmit;
	m_currentCommandBuffer.begin(beginInfo);

	Assertion(m_descriptorManager, "Vulkan DescriptorManager not initialized in setupFrame!");
	m_descriptorManager->beginFrame();

	Assertion(m_stateTracker, "Vulkan StateTracker not initialized in setupFrame!");
	m_stateTracker->beginFrame(m_currentCommandBuffer);

	// Reset the post-processing scratch UBO ring cursor for this frame-in-flight
	// slot (safe: acquireNextSwapChainImage already waited on this slot's fence)
	if (m_postProcessor) {
		m_postProcessor->beginFrame(m_currentFrame);
	}

	// Reset timestamp queries that were written last frame (must be outside render pass)
	if (m_queryManager) {
		m_queryManager->beginFrame(m_currentCommandBuffer);
	}

	// Reset per-frame flags
	m_sceneDepthCopiedThisFrame = false;
	m_sceneDepthSaved = false;

	// Reset per-frame draw statistics
	Assertion(m_drawManager, "Vulkan DrawManager not initialized in setupFrame!");
	m_drawManager->resetFrameStats();

	// Begin the composition render pass (clears color to black, depth to far plane)
	std::array<vk::ClearValue, 2> clearValues;
	clearValues[0].color.setFloat32({0.0f, 0.0f, 0.0f, 1.0f});
	clearValues[1].depthStencil = vk::ClearDepthStencilValue(1.0f, 0);

	PassBeginDesc pass;
	pass.renderPass = m_renderPass.get();
	pass.framebuffer = m_swapChainFramebuffers[m_currentSwapChainImage].get();
	pass.extent = m_renderExtent;
	pass.clearValues = clearValues;
	beginTrackedRenderPass(pass);

	m_frameInProgress = true;
}

void VulkanRenderer::flip()
{
	if (!m_frameInProgress) {
		nprintf(("Vulkan", "VulkanRenderer::flip called without frame in progress, skipping\n"));
		return;
	}

	// Print per-frame diagnostic summary before ending
	Assertion(m_drawManager, "Vulkan DrawManager not initialized in flip!");
	m_drawManager->printFrameStats();

	// End the composition render pass (composition image is now in
	// eShaderReadOnlyOptimal) and run the final output-encode pass that writes
	// the actual swap chain image (SDR passthrough or HDR10 PQ/BT.2020).
	// Tolerates the pass having already been ended: the OpenXR flip has to end
	// it itself to record its swapchain blit before handing off to us.
	endCurrentRenderPass();

#ifdef __APPLE__
	// MoltenVK: the encode render pass's VK_SUBPASS_EXTERNAL dependency (see
	// createEncodeRenderPass(): srcStage=eColorAttachmentOutput|eFragmentShader,
	// srcAccess=eColorAttachmentWrite, dst covers the encode's eShaderRead) is
	// spec-legal and sufficient on desktop Vulkan drivers, and -gr_sync_validation
	// confirms the composition-image ordering is clean there without this
	// barrier. It is kept only because MoltenVK's translation of the implicit
	// cross-render-pass sync into Metal fences/barriers has historically been
	// unreliable (tearing/garbage in the composition image once the encode pass
	// samples it). RE-TEST on macOS hardware; if MoltenVK now honors the subpass
	// dependency, this explicit barrier can be removed.
	if (m_currentSwapChainImage < m_compositionImages.size()) {
		ImageBarrier2 compositionBarrier;
		compositionBarrier.image = m_compositionImages[m_currentSwapChainImage].get();
		compositionBarrier.levelCount = 1;
		compositionBarrier.layerCount = 1;
		compositionBarrier.oldLayout = vk::ImageLayout::eShaderReadOnlyOptimal;
		compositionBarrier.newLayout = vk::ImageLayout::eShaderReadOnlyOptimal;
		compositionBarrier.srcStage = vk::PipelineStageFlagBits2::eColorAttachmentOutput;
		compositionBarrier.srcAccess = vk::AccessFlagBits2::eColorAttachmentWrite;
		compositionBarrier.dstStage = vk::PipelineStageFlagBits2::eFragmentShader;
		compositionBarrier.dstAccess = vk::AccessFlagBits2::eShaderSampledRead;

		cmdImageBarrier(m_currentCommandBuffer, compositionBarrier);
	}
#endif

	encodeToSwapChain();
	m_stateTracker->endFrame();

	// End command buffer
	m_currentCommandBuffer.end();

	// Set up cleanup callback for command buffers
	auto buffersToFree = m_currentCommandBuffers;
	m_frames[m_currentFrame]->onFrameFinished([this, buffersToFree]() mutable {
		m_device->freeCommandBuffers(m_graphicsCommandPool.get(), buffersToFree);
	});

	// Submit and present
	auto presentStatus = m_frames[m_currentFrame]->submitAndPresent(m_currentCommandBuffers,
		m_renderingFinishedSemaphores[m_currentSwapChainImage].get());

	if (shouldRecreateSwapChain(presentStatus)) {
		m_swapChainNeedsRecreation = true;
	}

	// Notify query manager that this frame's command buffer was submitted
	if (m_queryManager) {
		m_queryManager->notifySubmission();
	}

	// Track which swap chain image was just presented so saveScreen() can read it
	m_previousSwapChainImage = m_currentSwapChainImage;

	// Clear current command buffer reference
	m_currentCommandBuffer = nullptr;
	m_currentCommandBuffers.clear();
	m_frameInProgress = false;

	// Advance the single frame-in-flight index and push it to every consumer that
	// tracks it, so they all agree by construction. Done immediately after
	// incrementing so any buffer/descriptor operations before setupFrame() use the
	// correct frame.
	m_currentFrame = (m_currentFrame + 1) % MAX_FRAMES_IN_FLIGHT;
	++m_frameNumber;

	m_bufferManager->setCurrentFrame(m_currentFrame, m_frameNumber);
	m_descriptorManager->setCurrentFrame(m_currentFrame);

	acquireNextSwapChainImage();

	// Process deferred resource deletions AFTER the fence wait in
	// acquireNextSwapChainImage, so we know the previous frame's commands
	// (including async upload CBs) have completed before destroying resources.
	m_deletionQueue->processDestructions();
}

void VulkanRenderer::beginSceneRendering()
{
	if (!m_postProcessor || !m_postProcessor->isInitialized()) {
		return;
	}
	if (m_sceneRendering) {
		return;
	}

	// End the current swap chain render pass
	m_currentCommandBuffer.endRenderPass();

	// Use G-buffer render pass when deferred lighting is enabled and G-buffer is ready
	m_useGbufRenderPass = m_postProcessor->deferred().isInitialized() && light_deferred_enabled();

	// Begin the HDR scene render pass (or G-buffer render pass for deferred)
	PassBeginDesc pass;
	pass.extent = m_postProcessor->getSceneExtent();

	if (m_useGbufRenderPass) {
		// Clear values: 6 color + depth
		std::array<vk::ClearValue, VulkanDeferredGBuffer::GBUF_COLOR_ATTACHMENT_COUNT + 1> clearValues{};
		clearValues[VulkanDeferredGBuffer::GBUF_ATT_COLOR].color.setFloat32({0.0f, 0.0f, 0.0f, 1.0f});
		clearValues[VulkanDeferredGBuffer::GBUF_ATT_POSITION].color.setFloat32({0.0f, 0.0f, 0.0f, 0.0f});
		clearValues[VulkanDeferredGBuffer::GBUF_ATT_NORMAL].color.setFloat32({0.0f, 0.0f, 0.0f, 0.0f});
		clearValues[VulkanDeferredGBuffer::GBUF_ATT_SPECULAR].color.setFloat32({0.0f, 0.0f, 0.0f, 0.0f});
		clearValues[VulkanDeferredGBuffer::GBUF_ATT_EMISSIVE].color.setFloat32({0.0f, 0.0f, 0.0f, 0.0f});
		clearValues[VulkanDeferredGBuffer::GBUF_ATT_COMPOSITE].color.setFloat32({0.0f, 0.0f, 0.0f, 0.0f});
		clearValues[VulkanDeferredGBuffer::GBUF_COLOR_ATTACHMENT_COUNT].depthStencil = vk::ClearDepthStencilValue(1.0f, 0);

		pass.renderPass = m_postProcessor->deferred().renderPass();
		pass.framebuffer = m_postProcessor->deferred().framebuffer();
		pass.clearValues = clearValues;
		pass.colorAttachmentCount = VulkanDeferredGBuffer::GBUF_COLOR_ATTACHMENT_COUNT;
		beginTrackedRenderPass(pass);
	} else {
		std::array<vk::ClearValue, 2> clearValues;
		clearValues[0].color.setFloat32({0.0f, 0.0f, 0.0f, 1.0f});
		clearValues[1].depthStencil = vk::ClearDepthStencilValue(1.0f, 0);

		pass.renderPass = m_postProcessor->getSceneRenderPass();
		pass.framebuffer = m_postProcessor->getSceneFramebuffer();
		pass.clearValues = clearValues;
		beginTrackedRenderPass(pass);
	}

	m_sceneRendering = true;
}

void VulkanRenderer::resumeSceneRendering()
{
	PassBeginDesc pass;
	pass.renderPass = m_postProcessor->getSceneRenderPassLoad();
	pass.framebuffer = m_postProcessor->getSceneFramebuffer();
	pass.extent = m_postProcessor->getSceneExtent();
	beginTrackedRenderPass(pass);
}

void VulkanRenderer::endSceneRendering()
{
	if (!m_postProcessor || !m_postProcessor->isInitialized()) {
		return;
	}
	if (!m_sceneRendering) {
		return;
	}

	// End HDR scene render pass (transitions scene color to eShaderReadOnlyOptimal)
	m_currentCommandBuffer.endRenderPass();

	// Update distortion ping-pong textures (every ~30ms, matching OpenGL)
	if (Gr_framebuffer_effects.any_set()) {
		m_postProcessor->updateDistortion(m_currentCommandBuffer, flFrametime);
	}

	// Execute post-processing passes (all between HDR scene pass and swap chain pass)
	m_postProcessor->executeBloom(m_currentCommandBuffer);
	m_postProcessor->executeTonemap(m_currentCommandBuffer);
	m_postProcessor->executeFXAA(m_currentCommandBuffer);
	m_postProcessor->executeSMAA(m_currentCommandBuffer);
	m_postProcessor->executeLightshafts(m_currentCommandBuffer);
	m_postProcessor->executePostEffects(m_currentCommandBuffer);

	// Begin the resumed swap chain render pass (loadOp=eLoad to preserve pre-scene content).
	// Non-flipped viewport for the post-processing blit (HDR texture is already in
	// Vulkan orientation); restored to flipped for HUD rendering below.
	std::array<vk::ClearValue, 2> clearValues;
	clearValues[0].color.setFloat32({0.0f, 0.0f, 0.0f, 1.0f});
	clearValues[1].depthStencil = vk::ClearDepthStencilValue(1.0f, 0);

	PassBeginDesc pass;
	pass.renderPass = m_renderPassLoad.get();
	pass.framebuffer = m_swapChainFramebuffers[m_currentSwapChainImage].get();
	pass.extent = m_renderExtent;
	pass.clearValues = clearValues;
	pass.viewport = PassViewport::NoFlip;
	beginTrackedRenderPass(pass);

	// Blit the HDR scene to swap chain through post-processing
	m_postProcessor->blitToSwapChain(m_currentCommandBuffer);

	// Restore Y-flipped viewport for HUD rendering
	m_stateTracker->setViewport(0.0f,
		static_cast<float>(m_renderExtent.height),
		static_cast<float>(m_renderExtent.width),
		-static_cast<float>(m_renderExtent.height));

	m_sceneRendering = false;
	m_useGbufRenderPass = false;
}

void VulkanRenderer::copyEffectTexture()
{
	if (!m_sceneRendering || !m_postProcessor || !m_postProcessor->isInitialized()) {
		return;
	}

	// End the current scene render pass
	// This transitions scene color to eShaderReadOnlyOptimal (the render pass's finalLayout)
	// For G-buffer: all 6 color attachments transition to eShaderReadOnlyOptimal
	m_currentCommandBuffer.endRenderPass();

	// Copy scene color → effect texture (handles scene color transitions)
	m_postProcessor->copyEffectTexture(m_currentCommandBuffer);

	// If G-buffer is active, transition attachments 1-5 for render pass resume
	if (m_useGbufRenderPass) {
		m_postProcessor->deferred().transitionForResume(m_currentCommandBuffer);
	}

	// Resume the scene render pass with loadOp=eLoad to preserve existing content
	// Scene color is now in eColorAttachmentOptimal (copyEffectTexture transitions it back)
	// Depth is still in eDepthStencilAttachmentOptimal (untouched by the copy)
	resumeScenePassAfterCopy();
}

// Shared tail of copyEffectTexture()/copySceneDepthForParticles(): resume the
// scene (or G-buffer) render pass with loadOp=eLoad after a mid-scene copy.
void VulkanRenderer::resumeScenePassAfterCopy()
{
	PassBeginDesc pass;
	pass.extent = m_postProcessor->getSceneExtent();

	if (m_useGbufRenderPass) {
		// Clear values ignored for eLoad but array must cover all attachments
		std::array<vk::ClearValue, VulkanDeferredGBuffer::GBUF_COLOR_ATTACHMENT_COUNT + 1> clearValues{};
		clearValues[VulkanDeferredGBuffer::GBUF_COLOR_ATTACHMENT_COUNT].depthStencil = vk::ClearDepthStencilValue(1.0f, 0);

		pass.renderPass = m_postProcessor->deferred().renderPassLoad();
		pass.framebuffer = m_postProcessor->deferred().framebuffer();
		pass.clearValues = clearValues;
		pass.colorAttachmentCount = VulkanDeferredGBuffer::GBUF_COLOR_ATTACHMENT_COUNT;
		beginTrackedRenderPass(pass);
	} else {
		std::array<vk::ClearValue, 2> clearValues;
		clearValues[0].color.setFloat32({0.0f, 0.0f, 0.0f, 1.0f});
		clearValues[1].depthStencil = vk::ClearDepthStencilValue(1.0f, 0);

		pass.renderPass = m_postProcessor->getSceneRenderPassLoad();
		pass.framebuffer = m_postProcessor->getSceneFramebuffer();
		pass.clearValues = clearValues;
		beginTrackedRenderPass(pass);
	}
}

void VulkanRenderer::copySceneDepthForParticles()
{
	if (m_sceneDepthCopiedThisFrame || !m_sceneRendering || !m_postProcessor || !m_postProcessor->isInitialized()) {
		return;
	}

	// End the current scene render pass
	// This transitions: color → eShaderReadOnlyOptimal, depth → eDepthStencilAttachmentOptimal
	// For G-buffer: all 6 color attachments → eShaderReadOnlyOptimal
	m_currentCommandBuffer.endRenderPass();

	// Copy scene depth → samplable depth copy (handles all depth image transitions)
	m_postProcessor->copySceneDepth(m_currentCommandBuffer);

	resumeScenePassAfterDepthCopy();

	m_sceneDepthCopiedThisFrame = true;
}

// Shared tail of every mid-scene copy that touches only depth: put the color
// attachments back the way the resumed loadOp=eLoad pass expects them, then resume.
void VulkanRenderer::resumeScenePassAfterDepthCopy()
{
	// Transition scene color: eShaderReadOnlyOptimal → eColorAttachmentOptimal
	// (needed for the resumed render pass with loadOp=eLoad, which expects
	// initialLayout=eColorAttachmentOptimal; a depth copy only touches depth)
	{
		ImageBarrier2 barrier;
		barrier.image = m_postProcessor->getSceneColorImage();
		barrier.levelCount = 1;
		barrier.layerCount = 1;
		barrier.oldLayout = vk::ImageLayout::eShaderReadOnlyOptimal;
		barrier.newLayout = vk::ImageLayout::eColorAttachmentOptimal;
		barrier.srcStage = vk::PipelineStageFlagBits2::eColorAttachmentOutput;
		barrier.srcAccess = {};
		barrier.dstStage = vk::PipelineStageFlagBits2::eColorAttachmentOutput;
		// eColorAttachmentRead as well as Write: resumeScenePassAfterCopy() resumes
		// the scene pass with loadOp=eLoad, which reads this attachment; the read
		// must be ordered after the transition (else READ_AFTER_WRITE).
		barrier.dstAccess = vk::AccessFlagBits2::eColorAttachmentWrite
		                  | vk::AccessFlagBits2::eColorAttachmentRead;

		cmdImageBarrier(m_currentCommandBuffer, barrier);
	}

	// If G-buffer is active, transition attachments 1-5 for render pass resume
	if (m_useGbufRenderPass) {
		m_postProcessor->deferred().transitionForResume(m_currentCommandBuffer);
	}

	// Resume the scene render pass with loadOp=eLoad
	resumeScenePassAfterCopy();
}

// Head of every mid-scene depth copy: end the scene (or G-buffer) pass, which leaves the color
// attachments in eShaderReadOnlyOptimal and depth in eDepthStencilAttachmentOptimal.
// resumeScenePassAfterCopy() knows the scene pass and the non-MSAA G-buffer pass only. The
// player-ship callers run between one deferred pass and the next, so the multisampled G-buffer
// pass is never live -- resuming the wrong pass would desync the state tracker.
void VulkanRenderer::endScenePassForDepthCopy()
{
	Assertion(m_stateTracker->getCurrentSampleCount() == vk::SampleCountFlagBits::e1,
		"Tried to copy the scene depth while a multisampled render pass was active!");
	m_currentCommandBuffer.endRenderPass();
}

// The cockpit model is rendered around the camera, inside the ship hull that the scene
// pass already drew, so it needs a depth buffer that does not know about that hull --
// otherwise the hull wins the depth test and shows through the cockpit. OpenGL swaps
// the depth attachment to Cockpit_depth_texture for the duration; Vulkan bakes the
// attachment into the framebuffer, so the scene depth is copied aside and cleared
// instead. Only the scene depth image is parked: with MSAA the cockpit renders against
// the multisampled depth, which the G-buffer pass clears on its own, and
// gr_deferred_lighting_msaa() resolves back into the scene depth before restore runs.
void VulkanRenderer::saveSceneDepth()
{
	if (m_sceneDepthSaved || !m_sceneRendering || !m_postProcessor || !m_postProcessor->isInitialized()) {
		return;
	}

	endScenePassForDepthCopy();
	m_postProcessor->saveSceneDepth(m_currentCommandBuffer);
	resumeScenePassAfterDepthCopy();

	m_sceneDepthSaved = true;
}

void VulkanRenderer::restoreSceneDepth()
{
	if (!m_sceneDepthSaved) {
		return;
	}

	// Cleared first: a scene that ends between the save and the restore (a failed
	// resize dropping the post-processor, say) must not leave the flag set for the
	// next frame's restore to act on stale content.
	m_sceneDepthSaved = false;

	if (!m_sceneRendering || !m_postProcessor || !m_postProcessor->isInitialized()) {
		return;
	}

	endScenePassForDepthCopy();
	m_postProcessor->restoreSceneDepth(m_currentCommandBuffer);
	resumeScenePassAfterDepthCopy();
}

void VulkanRenderer::beginRenderTarget(tcache_slot_vulkan* ts, int face)
{
	// End current render pass (swap chain or previous RT face)
	m_currentCommandBuffer.endRenderPass();

	// Select the correct framebuffer for cubemap face or flat RT
	vk::Framebuffer fb = (ts->isCubemap && face >= 0 && face < 6)
	                    ? ts->cubeFaceFramebuffers[face] : ts->framebuffer;

	// Clear values must match the render pass attachments: color at index 0, and
	// depth at index 1 when this target has a depth attachment.
	std::array<vk::ClearValue, 2> clearValues;
	clearValues[0].color = m_stateTracker->getClearColor();
	clearValues[1].depthStencil = vk::ClearDepthStencilValue(1.0f, 0);
	const bool hasDepth = static_cast<bool>(ts->depthImage);

	PassBeginDesc pass;
	pass.renderPass = ts->renderPass;
	pass.framebuffer = fb;
	pass.extent = vk::Extent2D(ts->width, ts->height);
	pass.clearValues = ArrayView<vk::ClearValue>(clearValues.data(), hasDepth ? 2 : 1);
	// The engine sets the RTT viewport itself via gr_set_viewport (positive
	// height; the RTT projection matrix handles the Y-flip), so keep it.
	pass.viewport = PassViewport::Keep;
	beginTrackedRenderPass(pass);

	m_renderTargetActive = true;
}

void VulkanRenderer::endRenderTarget(tcache_slot_vulkan* ts)
{
	if (!m_renderTargetActive) {
		return;
	}

	// End the RT render pass (finalLayout transitions mip 0 to eShaderReadOnlyOptimal)
	m_currentCommandBuffer.endRenderPass();
	m_renderTargetActive = false;

	// Render passes only ever draw into mip 0 (each face's framebuffer is a
	// single-mip view), so higher mips are otherwise left uninitialized.
	// Regenerate the chain now via blits so effects that sample it with an
	// explicit LOD (e.g. the env map's roughness-based reflection blur) see
	// real data instead of garbage/undefined content.
	if (ts && ts->mipLevels > 1) {
		uint32_t layers = ts->isCubemap ? 6u : ts->arrayLayers;

		ImageBarrier2 barrier;
		barrier.image = ts->image;
		barrier.levelCount = 1;
		barrier.layerCount = layers;
		barrier.oldLayout = vk::ImageLayout::eShaderReadOnlyOptimal;
		barrier.newLayout = vk::ImageLayout::eTransferSrcOptimal;
		barrier.srcStage = vk::PipelineStageFlagBits2::eColorAttachmentOutput;
		barrier.srcAccess = vk::AccessFlagBits2::eColorAttachmentWrite;
		barrier.dstStage = vk::PipelineStageFlagBits2::eBlit;
		barrier.dstAccess = vk::AccessFlagBits2::eTransferRead;

		cmdImageBarrier(m_currentCommandBuffer, barrier);

		vulkan_generate_mipmap_chain(m_currentCommandBuffer, ts->image, ts->width, ts->height, ts->mipLevels, layers);
	}

	resumeSwapChainPass();
}

void VulkanRenderer::resumeSwapChainPass()
{
	std::array<vk::ClearValue, 2> clearValues;
	clearValues[0].color.setFloat32({0.0f, 0.0f, 0.0f, 1.0f});
	clearValues[1].depthStencil = vk::ClearDepthStencilValue(1.0f, 0);

	PassBeginDesc pass;
	pass.renderPass = m_renderPassLoad.get();
	pass.framebuffer = m_swapChainFramebuffers[m_currentSwapChainImage].get();
	pass.extent = m_renderExtent;
	pass.clearValues = clearValues;
	beginTrackedRenderPass(pass);
}

void VulkanRenderer::restartCompositionPass()
{
	std::array<vk::ClearValue, 2> clearValues;
	clearValues[0].color.setFloat32({0.0f, 0.0f, 0.0f, 1.0f});
	clearValues[1].depthStencil = vk::ClearDepthStencilValue(1.0f, 0);

	PassBeginDesc pass;
	pass.renderPass = m_renderPass.get();
	pass.framebuffer = m_swapChainFramebuffers[m_currentSwapChainImage].get();
	pass.extent = m_renderExtent;
	pass.clearValues = clearValues;
	beginTrackedRenderPass(pass);
}

void VulkanRenderer::endCurrentRenderPass()
{
	if (!m_stateTracker->getCurrentRenderPass()) {
		return;
	}

	m_currentCommandBuffer.endRenderPass();
	m_stateTracker->setRenderPass(vk::RenderPass());
}

void VulkanRenderer::resumeRenderTargetPass(tcache_slot_vulkan* ts)
{
	// loadOp=eLoad on color keeps whatever was already drawn into the target; depth (if
	// any) still clears. Only the depth clear value is consumed, but supply both so the
	// index layout matches the pass attachments.
	std::array<vk::ClearValue, 2> clearValues;
	clearValues[0].color = m_stateTracker->getClearColor();
	clearValues[1].depthStencil = vk::ClearDepthStencilValue(1.0f, 0);
	const bool hasDepth = static_cast<bool>(ts->depthImage);

	PassBeginDesc pass;
	pass.renderPass = ts->renderPassLoad;
	pass.framebuffer = ts->framebuffer;
	pass.extent = vk::Extent2D(ts->width, ts->height);
	pass.clearValues = ArrayView<vk::ClearValue>(clearValues.data(), hasDepth ? 2 : 1);
	// Match beginRenderTarget: the engine drives the RTT viewport via gr_set_viewport.
	pass.viewport = PassViewport::Keep;
	beginTrackedRenderPass(pass);

	m_renderTargetActive = true;
}

} // namespace graphics::vulkan