// Copyright 2018 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 DAWNNATIVE_DAWNNATIVE_H_
#define DAWNNATIVE_DAWNNATIVE_H_

#include <dawn/dawn_proc_table.h>
#include <dawn/webgpu.h>
#include <dawn_native/dawn_native_export.h>

#include <string>
#include <vector>

namespace dawn::platform {
    class Platform;
}  // namespace dawn::platform

namespace wgpu {
    struct AdapterProperties;
    struct DeviceDescriptor;
}

namespace dawn_native {

    class InstanceBase;
    class AdapterBase;

    // An optional parameter of Adapter::CreateDevice() to send additional information when creating
    // a Device. For example, we can use it to enable a workaround, optimization or feature.
    struct DAWN_NATIVE_EXPORT DawnDeviceDescriptor {
        std::vector<const char*> requiredFeatures;
        std::vector<const char*> forceEnabledToggles;
        std::vector<const char*> forceDisabledToggles;

        const WGPURequiredLimits* requiredLimits = nullptr;
    };

    // A struct to record the information of a toggle. A toggle is a code path in Dawn device that
    // can be manually configured to run or not outside Dawn, including workarounds, special
    // features and optimizations.
    struct ToggleInfo {
        const char* name;
        const char* description;
        const char* url;
    };

    // A struct to record the information of a feature. A feature is a GPU feature that is not
    // required to be supported by all Dawn backends and can only be used when it is enabled on the
    // creation of device.
    using FeatureInfo = ToggleInfo;

    // An adapter is an object that represent on possibility of creating devices in the system.
    // Most of the time it will represent a combination of a physical GPU and an API. Not that the
    // same GPU can be represented by multiple adapters but on different APIs.
    //
    // The underlying Dawn adapter is owned by the Dawn instance so this class is not RAII but just
    // a reference to an underlying adapter.
    class DAWN_NATIVE_EXPORT Adapter {
      public:
        Adapter();
        Adapter(AdapterBase* impl);
        ~Adapter();

        Adapter(const Adapter& other);
        Adapter& operator=(const Adapter& other);

        // Essentially webgpu.h's wgpuAdapterGetProperties while we don't have WGPUAdapter in
        // dawn.json
        void GetProperties(wgpu::AdapterProperties* properties) const;
        void GetProperties(WGPUAdapterProperties* properties) const;

        std::vector<const char*> GetSupportedExtensions() const;
        std::vector<const char*> GetSupportedFeatures() const;
        WGPUDeviceProperties GetAdapterProperties() const;
        bool GetLimits(WGPUSupportedLimits* limits) const;

        void SetUseTieredLimits(bool useTieredLimits);

        // Check that the Adapter is able to support importing external images. This is necessary
        // to implement the swapchain and interop APIs in Chromium.
        bool SupportsExternalImages() const;

        explicit operator bool() const;

        // Create a device on this adapter. On an error, nullptr is returned.
        WGPUDevice CreateDevice(const DawnDeviceDescriptor* deviceDescriptor);
        WGPUDevice CreateDevice(const wgpu::DeviceDescriptor* deviceDescriptor);
        WGPUDevice CreateDevice(const WGPUDeviceDescriptor* deviceDescriptor = nullptr);

        void RequestDevice(const DawnDeviceDescriptor* descriptor,
                           WGPURequestDeviceCallback callback,
                           void* userdata);
        void RequestDevice(const wgpu::DeviceDescriptor* descriptor,
                           WGPURequestDeviceCallback callback,
                           void* userdata);
        void RequestDevice(const WGPUDeviceDescriptor* descriptor,
                           WGPURequestDeviceCallback callback,
                           void* userdata);

        // Returns the underlying WGPUAdapter object.
        WGPUAdapter Get() const;

        // Reset the backend device object for testing purposes.
        void ResetInternalDeviceForTesting();

      private:
        AdapterBase* mImpl = nullptr;
    };

    // Base class for options passed to Instance::DiscoverAdapters.
    struct DAWN_NATIVE_EXPORT AdapterDiscoveryOptionsBase {
      public:
        const WGPUBackendType backendType;

      protected:
        AdapterDiscoveryOptionsBase(WGPUBackendType type);
    };

    enum BackendValidationLevel { Full, Partial, Disabled };

    // Represents a connection to dawn_native and is used for dependency injection, discovering
    // system adapters and injecting custom adapters (like a Swiftshader Vulkan adapter).
    //
    // This is an RAII class for Dawn instances and also controls the lifetime of all adapters
    // for this instance.
    class DAWN_NATIVE_EXPORT Instance {
      public:
        Instance();
        ~Instance();

        Instance(const Instance& other) = delete;
        Instance& operator=(const Instance& other) = delete;

        // Gather all adapters in the system that can be accessed with no special options. These
        // adapters will later be returned by GetAdapters.
        void DiscoverDefaultAdapters();

        // Adds adapters that can be discovered with the options provided (like a getProcAddress).
        // The backend is chosen based on the type of the options used. Returns true on success.
        bool DiscoverAdapters(const AdapterDiscoveryOptionsBase* options);

        // Returns all the adapters that the instance knows about.
        std::vector<Adapter> GetAdapters() const;

        const ToggleInfo* GetToggleInfo(const char* toggleName);
        const FeatureInfo* GetFeatureInfo(WGPUFeatureName feature);

        // Enables backend validation layers
        void EnableBackendValidation(bool enableBackendValidation);
        void SetBackendValidationLevel(BackendValidationLevel validationLevel);

        // Enable debug capture on Dawn startup
        void EnableBeginCaptureOnStartup(bool beginCaptureOnStartup);

        void SetPlatform(dawn::platform::Platform* platform);

        // Returns the underlying WGPUInstance object.
        WGPUInstance Get() const;

      private:
        InstanceBase* mImpl = nullptr;
    };

    // Backend-agnostic API for dawn_native
    DAWN_NATIVE_EXPORT const DawnProcTable& GetProcs();

    // Query the names of all the toggles that are enabled in device
    DAWN_NATIVE_EXPORT std::vector<const char*> GetTogglesUsed(WGPUDevice device);

    // Backdoor to get the number of lazy clears for testing
    DAWN_NATIVE_EXPORT size_t GetLazyClearCountForTesting(WGPUDevice device);

    // Backdoor to get the number of deprecation warnings for testing
    DAWN_NATIVE_EXPORT size_t GetDeprecationWarningCountForTesting(WGPUDevice device);

    //  Query if texture has been initialized
    DAWN_NATIVE_EXPORT bool IsTextureSubresourceInitialized(
        WGPUTexture texture,
        uint32_t baseMipLevel,
        uint32_t levelCount,
        uint32_t baseArrayLayer,
        uint32_t layerCount,
        WGPUTextureAspect aspect = WGPUTextureAspect_All);

    // Backdoor to get the order of the ProcMap for testing
    DAWN_NATIVE_EXPORT std::vector<const char*> GetProcMapNamesForTesting();

    DAWN_NATIVE_EXPORT bool DeviceTick(WGPUDevice device);

    // ErrorInjector functions used for testing only. Defined in dawn_native/ErrorInjector.cpp
    DAWN_NATIVE_EXPORT void EnableErrorInjector();
    DAWN_NATIVE_EXPORT void DisableErrorInjector();
    DAWN_NATIVE_EXPORT void ClearErrorInjector();
    DAWN_NATIVE_EXPORT uint64_t AcquireErrorInjectorCallCount();
    DAWN_NATIVE_EXPORT void InjectErrorAt(uint64_t index);

    // The different types of external images
    enum ExternalImageType {
        OpaqueFD,
        DmaBuf,
        IOSurface,
        DXGISharedHandle,
        EGLImage,
    };

    // Common properties of external images
    struct DAWN_NATIVE_EXPORT ExternalImageDescriptor {
      public:
        const ExternalImageType type;
        const WGPUTextureDescriptor* cTextureDescriptor;  // Must match image creation params
        bool isInitialized;  // Whether the texture is initialized on import

      protected:
        ExternalImageDescriptor(ExternalImageType type);
    };

    struct DAWN_NATIVE_EXPORT ExternalImageAccessDescriptor {
      public:
        bool isInitialized;  // Whether the texture is initialized on import
        WGPUTextureUsageFlags usage;
    };

    struct DAWN_NATIVE_EXPORT ExternalImageExportInfo {
      public:
        const ExternalImageType type;
        bool isInitialized;  // Whether the texture is initialized after export

      protected:
        ExternalImageExportInfo(ExternalImageType type);
    };

    DAWN_NATIVE_EXPORT const char* GetObjectLabelForTesting(void* objectHandle);

    DAWN_NATIVE_EXPORT uint64_t GetAllocatedSizeForTesting(WGPUBuffer buffer);

    DAWN_NATIVE_EXPORT bool BindGroupLayoutBindingsEqualForTesting(WGPUBindGroupLayout a,
                                                                   WGPUBindGroupLayout b);

}  // namespace dawn_native

#endif  // DAWNNATIVE_DAWNNATIVE_H_