/*
* All or portions of this file Copyright (c) Amazon.com, Inc. or its affiliates or
* its licensors.
*
* For complete copyright and license terms please see the LICENSE at the root of this
* distribution (the "License"). All use of this software is governed by the License,
* or, if provided, by the license below or the license accompanying this file. Do not
* remove or modify any license notices. This file is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*
*/

#include "GradientSignal_precompiled.h"
#include "Tests/GradientSignalTestMocks.h"

#include <AzTest/AzTest.h>

#include <Source/Components/ConstantGradientComponent.h>
#include <Source/Components/DitherGradientComponent.h>
#include <Source/Components/InvertGradientComponent.h>

namespace UnitTest
{
    struct GradientSignalServicesTestsFixture
        : public GradientSignalTest
    {
    };

    TEST_F(GradientSignalServicesTestsFixture, ConstantGradientComponent_KnownValue)
    {
        // Given a constant value as input, verify that sampling a set of points all produces that same constant value.

        constexpr float dataSize = 8.0f;
        constexpr float expectedOutput = 0.123f;
        GradientSignal::ConstantGradientConfig config;
        config.m_value = expectedOutput;

        auto entity = CreateEntity();
        CreateComponent<GradientSignal::ConstantGradientComponent>(entity.get(), config);
        ActivateEntity(entity.get());

        GradientSignal::GradientSampler gradientSampler;
        gradientSampler.m_gradientId = entity->GetId();
        for (float x = 0.0f; x < dataSize; x++)
        {
            for (float y = 0.0f; y < dataSize; y++)
            {
                GradientSignal::GradientSampleParams params;
                params.m_position = AZ::Vector3(x, y, 0.0f);
                EXPECT_EQ(expectedOutput, gradientSampler.GetValue(params));
            }
        }
    }

    TEST_F(GradientSignalServicesTestsFixture, DitherGradientComponent_4x4At50Pct)
    {
        // With a 4x4 gradient filled with 8/16 (0.5), verify that the resulting dithered output 
        // is an expected checkerboard pattern with 8 of 16 pixels filled.

        constexpr int dataSize = 4;

        AZStd::vector<float> inputData(dataSize * dataSize, 8.0f / 16.0f);
        AZStd::vector<float> expectedOutput =
        {
            1.0f, 0.0f, 1.0f, 0.0f,
            0.0f, 1.0f, 0.0f, 1.0f,
            1.0f, 0.0f, 1.0f, 0.0f,
            0.0f, 1.0f, 0.0f, 1.0f,
        };

        auto entityMock = CreateEntity();
        const AZ::EntityId id = entityMock->GetId();
        UnitTest::MockGradientArrayRequestsBus mockGradientRequestsBus(id, inputData, dataSize);

        GradientSignal::DitherGradientConfig config;
        config.m_useSystemPointsPerUnit = false;
        config.m_pointsPerUnit = 1.0f;
        config.m_patternOffset = AZ::Vector3::CreateZero();
        config.m_patternType = GradientSignal::DitherGradientConfig::BayerPatternType::PATTERN_SIZE_4x4;
        config.m_gradientSampler.m_gradientId = entityMock->GetId();

        auto entity = CreateEntity();
        CreateComponent<GradientSignal::DitherGradientComponent>(entity.get(), config);
        ActivateEntity(entity.get());

        TestFixedDataSampler(expectedOutput, dataSize, entity->GetId());
    }

    TEST_F(GradientSignalServicesTestsFixture, DitherGradientComponent_4x4At31Pct)
    {
        // With a 4x4 gradient filled with 5/16 (0.3125), verify that the resulting dithered output 
        // has the correct 5 of 16 pixels set

        constexpr int dataSize = 4;

        AZStd::vector<float> inputData(dataSize * dataSize, 5.0f / 16.0f);
        AZStd::vector<float> expectedOutput =
        {
            1.0f, 0.0f, 1.0f, 0.0f,
            0.0f, 1.0f, 0.0f, 0.0f,
            1.0f, 0.0f, 1.0f, 0.0f,
            0.0f, 0.0f, 0.0f, 0.0f,
        };

        auto entityMock = CreateEntity();
        const AZ::EntityId id = entityMock->GetId();
        UnitTest::MockGradientArrayRequestsBus mockGradientRequestsBus(id, inputData, dataSize);

        GradientSignal::DitherGradientConfig config;
        config.m_useSystemPointsPerUnit = false;
        config.m_pointsPerUnit = 1.0f;
        config.m_patternOffset = AZ::Vector3::CreateZero();
        config.m_patternType = GradientSignal::DitherGradientConfig::BayerPatternType::PATTERN_SIZE_4x4;
        config.m_gradientSampler.m_gradientId = entityMock->GetId();

        auto entity = CreateEntity();
        CreateComponent<GradientSignal::DitherGradientComponent>(entity.get(), config);
        ActivateEntity(entity.get());

        TestFixedDataSampler(expectedOutput, dataSize, entity->GetId());
    }

    TEST_F(GradientSignalServicesTestsFixture, DitherGradientComponent_8x8At50Pct)
    {
        // With an 8x8 gradient filled with 32/64 (0.5), verify that the resulting dithered output 
        // is an expected checkerboard pattern with 32 of 64 pixels filled.

        constexpr int dataSize = 8;

        AZStd::vector<float> inputData(dataSize * dataSize, 32.0f / 64.0f);
        AZStd::vector<float> expectedOutput =
        {
            1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f,
            0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f,
            1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f,
            0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f,
            1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f,
            0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f,
            1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f,
            0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f,
        };

        auto entityMock = CreateEntity();
        const AZ::EntityId id = entityMock->GetId();
        UnitTest::MockGradientArrayRequestsBus mockGradientRequestsBus(id, inputData, dataSize);

        GradientSignal::DitherGradientConfig config;
        config.m_useSystemPointsPerUnit = false;
        config.m_pointsPerUnit = 1.0f;
        config.m_patternOffset = AZ::Vector3::CreateZero();
        config.m_patternType = GradientSignal::DitherGradientConfig::BayerPatternType::PATTERN_SIZE_8x8;
        config.m_gradientSampler.m_gradientId = entityMock->GetId();

        auto entity = CreateEntity();
        CreateComponent<GradientSignal::DitherGradientComponent>(entity.get(), config);
        ActivateEntity(entity.get());

        TestFixedDataSampler(expectedOutput, dataSize, entity->GetId());
    }

    TEST_F(GradientSignalServicesTestsFixture, DitherGradientComponent_8x8At55Pct)
    {
        // With an 8x8 gradient filled with 35/64 (0.546875), verify that the resulting dithered output 
        // has the correct 35 of 64 pixels set

        constexpr int dataSize = 8;

        AZStd::vector<float> inputData(dataSize * dataSize, 35.0f / 64.0f);
        AZStd::vector<float> expectedOutput =
        {
            1.0f, 1.0f, 1.0f, 0.0f, 1.0f, 1.0f, 1.0f, 0.0f,
            0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f,
            1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f,
            0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f,
            1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f, 1.0f, 0.0f,
            0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f,
            1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f,
            0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f,
        };

        auto entityMock = CreateEntity();
        const AZ::EntityId id = entityMock->GetId();
        UnitTest::MockGradientArrayRequestsBus mockGradientRequestsBus(id, inputData, dataSize);

        GradientSignal::DitherGradientConfig config;
        config.m_useSystemPointsPerUnit = false;
        config.m_pointsPerUnit = 1.0f;
        config.m_patternOffset = AZ::Vector3::CreateZero();
        config.m_patternType = GradientSignal::DitherGradientConfig::BayerPatternType::PATTERN_SIZE_8x8;
        config.m_gradientSampler.m_gradientId = entityMock->GetId();

        auto entity = CreateEntity();
        CreateComponent<GradientSignal::DitherGradientComponent>(entity.get(), config);
        ActivateEntity(entity.get());

        TestFixedDataSampler(expectedOutput, dataSize, entity->GetId());
    }

    TEST_F(GradientSignalServicesTestsFixture, InvertGradientComponent_InvertKnownPoints)
    {
        // Try inverting 0, 1, 0.5, and 0.2 (endpoints, middle, and arbitrary value) and verify
        // that we get back the expected inverted results.

        constexpr int dataSize = 2;
        AZStd::vector<float> inputData =
        { 
            0.0f, 1.0f,
            0.5f, 0.2f
        };
        AZStd::vector<float> expectedOutput =
        {
            1.0f, 0.0f,
            0.5f, 0.8f
        };

        auto entityMock = CreateEntity();
        const AZ::EntityId id = entityMock->GetId();
        UnitTest::MockGradientArrayRequestsBus mockGradientRequestsBus(id, inputData, dataSize);

        GradientSignal::InvertGradientConfig config;
        config.m_gradientSampler.m_gradientId = entityMock->GetId();

        auto entity = CreateEntity();
        CreateComponent<GradientSignal::InvertGradientComponent>(entity.get(), config);
        ActivateEntity(entity.get());

        TestFixedDataSampler(expectedOutput, dataSize, entity->GetId());
    }
}