// 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.

#include <vector>

#include "dawn/native/Features.h"
#include "dawn/native/Instance.h"
#include "dawn/native/null/DeviceNull.h"
#include "gtest/gtest.h"

class FeatureTests : public testing::Test {
  public:
    FeatureTests()
        : testing::Test(),
          mInstanceBase(dawn::native::InstanceBase::Create()),
          mAdapterBase(mInstanceBase.Get()) {}

    std::vector<wgpu::FeatureName> GetAllFeatureNames() {
        std::vector<wgpu::FeatureName> allFeatureNames(kTotalFeaturesCount);
        for (size_t i = 0; i < kTotalFeaturesCount; ++i) {
            allFeatureNames[i] = FeatureEnumToAPIFeature(static_cast<dawn::native::Feature>(i));
        }
        return allFeatureNames;
    }

    static constexpr size_t kTotalFeaturesCount =
        static_cast<size_t>(dawn::native::Feature::EnumCount);

  protected:
    Ref<dawn::native::InstanceBase> mInstanceBase;
    dawn::native::null::Adapter mAdapterBase;
};

// Test the creation of a device will fail if the requested feature is not supported on the
// Adapter.
TEST_F(FeatureTests, AdapterWithRequiredFeatureDisabled) {
    const std::vector<wgpu::FeatureName> kAllFeatureNames = GetAllFeatureNames();
    for (size_t i = 0; i < kTotalFeaturesCount; ++i) {
        dawn::native::Feature notSupportedFeature = static_cast<dawn::native::Feature>(i);

        std::vector<wgpu::FeatureName> featureNamesWithoutOne = kAllFeatureNames;
        featureNamesWithoutOne.erase(featureNamesWithoutOne.begin() + i);

        mAdapterBase.SetSupportedFeatures(featureNamesWithoutOne);
        dawn::native::Adapter adapterWithoutFeature(&mAdapterBase);

        // Test that creating device with and without DisallowUnsafeApis toggle disabled will both
        // failed.

        // Without disabling DisallowUnsafeApis toggle
        {
            wgpu::DeviceDescriptor deviceDescriptor;
            wgpu::FeatureName featureName = FeatureEnumToAPIFeature(notSupportedFeature);
            deviceDescriptor.requiredFeatures = &featureName;
            deviceDescriptor.requiredFeaturesCount = 1;

            WGPUDevice deviceWithFeature = adapterWithoutFeature.CreateDevice(
                reinterpret_cast<const WGPUDeviceDescriptor*>(&deviceDescriptor));
            ASSERT_EQ(nullptr, deviceWithFeature);
        }

        // Disabling DisallowUnsafeApis toggle
        {
            wgpu::DeviceDescriptor unsafeDeviceDescriptor;
            wgpu::FeatureName featureName = FeatureEnumToAPIFeature(notSupportedFeature);
            unsafeDeviceDescriptor.requiredFeatures = &featureName;
            unsafeDeviceDescriptor.requiredFeaturesCount = 1;

            wgpu::DawnTogglesDeviceDescriptor togglesDesc;
            unsafeDeviceDescriptor.nextInChain = &togglesDesc;
            const char* toggle = "disallow_unsafe_apis";
            togglesDesc.forceDisabledToggles = &toggle;
            togglesDesc.forceDisabledTogglesCount = 1;

            WGPUDevice deviceWithFeature = adapterWithoutFeature.CreateDevice(
                reinterpret_cast<const WGPUDeviceDescriptor*>(&unsafeDeviceDescriptor));
            ASSERT_EQ(nullptr, deviceWithFeature);
        }
    }
}

// Test creating device requiring a supported feature can succeed (with DisallowUnsafeApis guarded
// for experimental features), and Device.GetEnabledFeatures() can return the names of the enabled
// features correctly.
TEST_F(FeatureTests, RequireAndGetEnabledFeatures) {
    dawn::native::Adapter adapter(&mAdapterBase);
    dawn::native::FeaturesInfo featuresInfo;

    for (size_t i = 0; i < kTotalFeaturesCount; ++i) {
        dawn::native::Feature feature = static_cast<dawn::native::Feature>(i);
        wgpu::FeatureName featureName = FeatureEnumToAPIFeature(feature);

        // Test with DisallowUnsafeApis not disabled.
        {
            wgpu::DeviceDescriptor deviceDescriptor;
            deviceDescriptor.requiredFeatures = &featureName;
            deviceDescriptor.requiredFeaturesCount = 1;

            dawn::native::DeviceBase* deviceBase = dawn::native::FromAPI(adapter.CreateDevice(
                reinterpret_cast<const WGPUDeviceDescriptor*>(&deviceDescriptor)));

            // Device creation should fail if requiring experimental features without disabling
            // DisallowUnsafeApis
            if (featuresInfo.GetFeatureInfo(featureName)->featureState ==
                dawn::native::FeatureInfo::FeatureState::Experimental) {
                ASSERT_EQ(nullptr, deviceBase);
            } else {
                // Requiring stable features should succeed.
                ASSERT_NE(nullptr, deviceBase);
                ASSERT_EQ(1u, deviceBase->APIEnumerateFeatures(nullptr));
                wgpu::FeatureName enabledFeature;
                deviceBase->APIEnumerateFeatures(&enabledFeature);
                EXPECT_EQ(enabledFeature, featureName);
                deviceBase->APIRelease();
            }
        }

        // Test with DisallowUnsafeApis disabled, creating device should always succeed.
        {
            wgpu::DeviceDescriptor unsafeDeviceDescriptor;
            unsafeDeviceDescriptor.requiredFeatures = &featureName;
            unsafeDeviceDescriptor.requiredFeaturesCount = 1;

            const char* const disableToggles[] = {"disallow_unsafe_apis"};
            wgpu::DawnTogglesDeviceDescriptor toggleDesc;
            toggleDesc.forceDisabledToggles = disableToggles;
            toggleDesc.forceDisabledTogglesCount = 1;
            unsafeDeviceDescriptor.nextInChain = &toggleDesc;

            dawn::native::DeviceBase* deviceBase = dawn::native::FromAPI(adapter.CreateDevice(
                reinterpret_cast<const WGPUDeviceDescriptor*>(&unsafeDeviceDescriptor)));

            ASSERT_NE(nullptr, deviceBase);
            ASSERT_EQ(1u, deviceBase->APIEnumerateFeatures(nullptr));
            wgpu::FeatureName enabledFeature;
            deviceBase->APIEnumerateFeatures(&enabledFeature);
            EXPECT_EQ(enabledFeature, featureName);
            deviceBase->APIRelease();
        }
    }
}