/*
 * Copyright 2015 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */


#ifndef GrVkRenderTarget_DEFINED
#define GrVkRenderTarget_DEFINED

#include "src/gpu/GrRenderTarget.h"
#include "src/gpu/vk/GrVkImage.h"

#include "include/gpu/vk/GrVkTypes.h"
#include "src/gpu/vk/GrVkCommandBuffer.h"
#include "src/gpu/vk/GrVkRenderPass.h"
#include "src/gpu/vk/GrVkResourceProvider.h"

class GrVkFramebuffer;
class GrVkGpu;
class GrVkImageView;
class GrVkAttachment;

struct GrVkImageInfo;

class GrVkRenderTarget: public GrRenderTarget, public virtual GrVkImage {
public:
    static sk_sp<GrVkRenderTarget> MakeWrappedRenderTarget(GrVkGpu*, SkISize, int sampleCnt,
                                                           const GrVkImageInfo&,
                                                           sk_sp<GrBackendSurfaceMutableStateImpl>);

    static sk_sp<GrVkRenderTarget> MakeSecondaryCBRenderTarget(GrVkGpu*, SkISize,
                                                               const GrVkDrawableInfo& vkInfo);

    ~GrVkRenderTarget() override;

    GrBackendFormat backendFormat() const override { return this->getBackendFormat(); }

    using SelfDependencyFlags = GrVkRenderPass::SelfDependencyFlags;

    const GrVkFramebuffer* getFramebuffer(bool withStencil, SelfDependencyFlags);

    const GrVkImageView* colorAttachmentView() const { return fColorAttachmentView.get(); }

    /**
     * If this render target is multisampled, this returns the MSAA image for rendering. This
     * will be different than *this* when we have separate render/resolve images. If not
     * multisampled returns nullptr.
     */
    GrVkImage* msaaImage();

    const GrVkImageView* resolveAttachmentView() const { return fResolveAttachmentView.get(); }
    const GrManagedResource* stencilImageResource() const;
    const GrVkImageView* stencilAttachmentView() const;

    // Returns the main target for draws. If using MSAA and we have a resolve target, it will be the
    // msaa attachment. Otherwise it will be this object.
    GrVkImage* colorAttachmentImage();

    const GrVkRenderPass* getSimpleRenderPass(bool withStencil, SelfDependencyFlags);
    GrVkResourceProvider::CompatibleRPHandle compatibleRenderPassHandle(bool withStencil,
                                                                        SelfDependencyFlags);
    const GrVkRenderPass* externalRenderPass() const;

    bool wrapsSecondaryCommandBuffer() const { return fSecondaryCommandBuffer != VK_NULL_HANDLE; }
    VkCommandBuffer getExternalSecondaryCommandBuffer() const {
        return fSecondaryCommandBuffer;
    }

    bool canAttemptStencilAttachment() const override {
        // We don't know the status of the stencil attachment for wrapped external secondary command
        // buffers so we just assume we don't have one.
        return !this->wrapsSecondaryCommandBuffer();
    }

    GrBackendRenderTarget getBackendRenderTarget() const override;

    void getAttachmentsDescriptor(GrVkRenderPass::AttachmentsDescriptor* desc,
                                  GrVkRenderPass::AttachmentFlags* flags,
                                  bool withStencil) const;

    // Reconstruct the render target attachment information from the programInfo. This includes
    // which attachments the render target will have (color, stencil) and the attachments' formats
    // and sample counts - cf. getAttachmentsDescriptor.
    static void ReconstructAttachmentsDescriptor(const GrVkCaps& vkCaps,
                                                 const GrProgramInfo& programInfo,
                                                 GrVkRenderPass::AttachmentsDescriptor* desc,
                                                 GrVkRenderPass::AttachmentFlags* flags);

    // So that we don't need to rewrite descriptor sets each time, we keep a cached input descriptor
    // set on the the RT and simply reuse that descriptor set for this render target only. This call
    // will not ref the GrVkDescriptorSet so the caller must manually ref it if it wants to keep it
    // alive.
    const GrVkDescriptorSet* inputDescSet(GrVkGpu*);

    void addResources(GrVkCommandBuffer& commandBuffer, bool withStencil, SelfDependencyFlags);

    void addWrappedGrSecondaryCommandBuffer(std::unique_ptr<GrVkSecondaryCommandBuffer> cmdBuffer) {
        fGrSecondaryCommandBuffers.push_back(std::move(cmdBuffer));
    }

protected:
    GrVkRenderTarget(GrVkGpu* gpu,
                     SkISize dimensions,
                     int sampleCnt,
                     const GrVkImageInfo& info,
                     sk_sp<GrBackendSurfaceMutableStateImpl> mutableState,
                     sk_sp<GrVkAttachment> msaaAttachment,
                     sk_sp<const GrVkImageView> colorAttachmentView,
                     sk_sp<const GrVkImageView> resolveAttachmentView,
                     GrBackendObjectOwnership);

    GrVkRenderTarget(GrVkGpu* gpu,
                     SkISize dimensions,
                     const GrVkImageInfo& info,
                     sk_sp<GrBackendSurfaceMutableStateImpl> mutableState,
                     sk_sp<const GrVkImageView> colorAttachmentView,
                     GrBackendObjectOwnership);

    void onAbandon() override;
    void onRelease() override;

    // This accounts for the texture's memory and any MSAA renderbuffer's memory.
    size_t onGpuMemorySize() const override {
        int numColorSamples = 0;
        if (this->numSamples() > 1) {
            // If we have an msaa attachment then its size will be handled by the attachment itself.
            if (!fMSAAAttachment) {
                numColorSamples += this->numSamples();
            }
            if (fResolveAttachmentView) {
                // Add one to account for the resolved VkImage.
                numColorSamples += 1;
            }
        } else {
            SkASSERT(!fResolveAttachmentView);
            numColorSamples = 1;
        }

        return GrSurface::ComputeSize(this->backendFormat(), this->dimensions(),
                                      numColorSamples, GrMipmapped::kNo);
    }

private:
    GrVkRenderTarget(GrVkGpu* gpu,
                     SkISize dimensions,
                     int sampleCnt,
                     const GrVkImageInfo& info,
                     sk_sp<GrBackendSurfaceMutableStateImpl> mutableState,
                     sk_sp<GrVkAttachment> msaaAttachment,
                     sk_sp<const GrVkImageView> colorAttachmentView,
                     sk_sp<const GrVkImageView> resolveAttachmentView);

    GrVkRenderTarget(GrVkGpu* gpu,
                     SkISize dimensions,
                     const GrVkImageInfo& info,
                     sk_sp<GrBackendSurfaceMutableStateImpl> mutableState,
                     sk_sp<const GrVkImageView> colorAttachmentView);

    GrVkRenderTarget(GrVkGpu* gpu,
                     SkISize dimensions,
                     const GrVkImageInfo& info,
                     sk_sp<GrBackendSurfaceMutableStateImpl> mutableState,
                     const GrVkRenderPass* renderPass,
                     VkCommandBuffer secondaryCommandBuffer);

    void setFlags(const GrVkImageInfo& info);

    GrVkGpu* getVkGpu() const;

    const GrVkRenderPass* createSimpleRenderPass(bool withStencil, SelfDependencyFlags);
    const GrVkFramebuffer* createFramebuffer(bool withStencil, SelfDependencyFlags);

    bool completeStencilAttachment() override;

    // In Vulkan we call the release proc after we are finished with the underlying
    // GrVkImage::Resource object (which occurs after the GPU has finished all work on it).
    void onSetRelease(sk_sp<GrRefCntedCallback> releaseHelper) override {
        // Forward the release proc on to GrVkImage
        this->setResourceRelease(std::move(releaseHelper));
    }

    void releaseInternalObjects();

    sk_sp<const GrVkImageView> fColorAttachmentView;
    sk_sp<GrVkAttachment>      fMSAAAttachment;
    sk_sp<const GrVkImageView> fResolveAttachmentView;

    // We can have a renderpass with and without stencil, input attachment dependency, and advanced
    // blend dependency. All three being completely orthogonal. Thus we have a total of 8 types of
    // render passes.
    static constexpr int kNumCachedRenderPasses = 8;

    const GrVkFramebuffer*                   fCachedFramebuffers[kNumCachedRenderPasses];
    const GrVkRenderPass*                    fCachedRenderPasses[kNumCachedRenderPasses];
    GrVkResourceProvider::CompatibleRPHandle fCompatibleRPHandles[kNumCachedRenderPasses];

    const GrVkDescriptorSet* fCachedInputDescriptorSet = nullptr;

    // If this render target wraps an external VkCommandBuffer, then this handle will be that
    // VkCommandBuffer and not VK_NULL_HANDLE. In this case the render target will not be backed by
    // an actual VkImage and will thus be limited in terms of what it can be used for.
    VkCommandBuffer fSecondaryCommandBuffer = VK_NULL_HANDLE;
    // When we wrap a secondary command buffer, we will record GrManagedResources onto it which need
    // to be kept alive till the command buffer gets submitted and the GPU has finished. However, in
    // the wrapped case, we don't know when the command buffer gets submitted and when it is
    // finished on the GPU since the client is in charge of that. However, we do require that the
    // client keeps the GrVkSecondaryCBDrawContext alive and call releaseResources on it once the
    // GPU is finished all the work. Thus we can use this to manage the lifetime of our
    // GrVkSecondaryCommandBuffers. By storing them on the GrVkRenderTarget, which is owned by the
    // SkGpuDevice on the GrVkSecondaryCBDrawContext, we assure that the GrManagedResources held by
    // the GrVkSecondaryCommandBuffer don't get deleted before they are allowed to.
    SkTArray<std::unique_ptr<GrVkCommandBuffer>> fGrSecondaryCommandBuffers;
};

#endif