// Copyright 2019 The Dawn Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef SRC_DAWN_NATIVE_D3D12_RENDERPASSBUILDERD3D12_H_
#define SRC_DAWN_NATIVE_D3D12_RENDERPASSBUILDERD3D12_H_

#include <array>

#include "dawn/common/Constants.h"
#include "dawn/common/ityp_array.h"
#include "dawn/common/ityp_span.h"
#include "dawn/native/IntegerTypes.h"
#include "dawn/native/d3d12/d3d12_platform.h"
#include "dawn/native/dawn_platform.h"

namespace dawn::native::d3d12 {

class TextureView;

// RenderPassBuilder stores parameters related to render pass load and store operations.
// When the D3D12 render pass API is available, the needed descriptors can be fetched
// directly from the RenderPassBuilder. When the D3D12 render pass API is not available, the
// descriptors are still fetched and any information necessary to emulate the load and store
// operations is extracted from the descriptors.
class RenderPassBuilder {
  public:
    explicit RenderPassBuilder(bool hasUAV);

    // Returns the highest color attachment index + 1. If there is no color attachment, returns
    // 0. Range: [0, kMaxColorAttachments + 1)
    ColorAttachmentIndex GetHighestColorAttachmentIndexPlusOne() const;

    // Returns descriptors that are fed directly to BeginRenderPass, or are used as parameter
    // storage if D3D12 render pass API is unavailable.
    ityp::span<ColorAttachmentIndex, const D3D12_RENDER_PASS_RENDER_TARGET_DESC>
    GetRenderPassRenderTargetDescriptors() const;
    const D3D12_RENDER_PASS_DEPTH_STENCIL_DESC* GetRenderPassDepthStencilDescriptor() const;

    D3D12_RENDER_PASS_FLAGS GetRenderPassFlags() const;

    // Returns attachment RTVs to use with OMSetRenderTargets.
    const D3D12_CPU_DESCRIPTOR_HANDLE* GetRenderTargetViews() const;

    bool HasDepthOrStencil() const;

    // Functions that set the appropriate values in the render pass descriptors.
    void SetDepthAccess(wgpu::LoadOp loadOp,
                        wgpu::StoreOp storeOp,
                        float clearDepth,
                        DXGI_FORMAT format);
    void SetDepthNoAccess();
    void SetDepthStencilNoAccess();
    void SetRenderTargetBeginningAccess(ColorAttachmentIndex attachment,
                                        wgpu::LoadOp loadOp,
                                        dawn::native::Color clearColor,
                                        DXGI_FORMAT format);
    void SetRenderTargetEndingAccess(ColorAttachmentIndex attachment, wgpu::StoreOp storeOp);
    void SetRenderTargetEndingAccessResolve(ColorAttachmentIndex attachment,
                                            wgpu::StoreOp storeOp,
                                            TextureView* resolveSource,
                                            TextureView* resolveDestination);
    void SetStencilAccess(wgpu::LoadOp loadOp,
                          wgpu::StoreOp storeOp,
                          uint8_t clearStencil,
                          DXGI_FORMAT format);
    void SetStencilNoAccess();

    void SetRenderTargetView(ColorAttachmentIndex attachmentIndex,
                             D3D12_CPU_DESCRIPTOR_HANDLE baseDescriptor,
                             bool isNullRTV);
    void SetDepthStencilView(D3D12_CPU_DESCRIPTOR_HANDLE baseDescriptor);

  private:
    ColorAttachmentIndex mHighestColorAttachmentIndexPlusOne{uint8_t(0)};
    bool mHasDepthOrStencil = false;
    D3D12_RENDER_PASS_FLAGS mRenderPassFlags = D3D12_RENDER_PASS_FLAG_NONE;
    D3D12_RENDER_PASS_DEPTH_STENCIL_DESC mRenderPassDepthStencilDesc;
    ityp::array<ColorAttachmentIndex, D3D12_RENDER_PASS_RENDER_TARGET_DESC, kMaxColorAttachments>
        mRenderPassRenderTargetDescriptors;
    ityp::array<ColorAttachmentIndex, D3D12_CPU_DESCRIPTOR_HANDLE, kMaxColorAttachments>
        mRenderTargetViews;
    ityp::array<ColorAttachmentIndex,
                D3D12_RENDER_PASS_ENDING_ACCESS_RESOLVE_SUBRESOURCE_PARAMETERS,
                kMaxColorAttachments>
        mSubresourceParams;
};
}  // namespace dawn::native::d3d12

#endif  // SRC_DAWN_NATIVE_D3D12_RENDERPASSBUILDERD3D12_H_