#include <gtest/gtest.h>

#include <XCEngine/Core/Math/Bounds.h>
#include <XCEngine/Resources/GaussianSplat/GaussianSplat.h>

using namespace XCEngine::Resources;
using namespace XCEngine::Math;

namespace {

TEST(GaussianSplat, ResolvesSHOrderFromCoefficientCount) {
    EXPECT_EQ(ResolveGaussianSplatSHOrderFromCoefficientCount(0u), 0u);
    EXPECT_EQ(ResolveGaussianSplatSHOrderFromCoefficientCount(9u), 1u);
    EXPECT_EQ(ResolveGaussianSplatSHOrderFromCoefficientCount(24u), 2u);
    EXPECT_EQ(ResolveGaussianSplatSHOrderFromCoefficientCount(45u), 3u);
    EXPECT_EQ(ResolveGaussianSplatSHOrderFromCoefficientCount(46u), 0u);
}

TEST(GaussianSplat, CreateOwnedStoresMetadataSectionsAndPayload) {
    GaussianSplat gaussianSplat;

    GaussianSplatMetadata metadata;
    metadata.contentVersion = 7u;
    metadata.splatCount = 2u;
    metadata.bounds.SetMinMax(Vector3(-1.0f, -2.0f, -3.0f), Vector3(4.0f, 5.0f, 6.0f));
    metadata.positionFormat = GaussianSplatSectionFormat::VectorFloat32;
    metadata.otherFormat = GaussianSplatSectionFormat::OtherFloat32;
    metadata.colorFormat = GaussianSplatSectionFormat::ColorRGBA32F;
    metadata.shFormat = GaussianSplatSectionFormat::SHFloat32;

    XCEngine::Containers::Array<GaussianSplatSection> sections;
    sections.PushBack(GaussianSplatSection{
        GaussianSplatSectionType::Positions,
        GaussianSplatSectionFormat::VectorFloat32,
        0u,
        24u,
        2u,
        12u
    });

    XCEngine::Containers::Array<XCEngine::Core::uint8> payload;
    payload.Resize(24u);
    for (size_t index = 0; index < payload.Size(); ++index) {
        payload[index] = static_cast<XCEngine::Core::uint8>(index);
    }

    ASSERT_TRUE(gaussianSplat.CreateOwned(metadata, std::move(sections), std::move(payload)));
    EXPECT_TRUE(gaussianSplat.IsValid());
    EXPECT_EQ(gaussianSplat.GetType(), ResourceType::GaussianSplat);
    EXPECT_EQ(gaussianSplat.GetContentVersion(), 7u);
    EXPECT_EQ(gaussianSplat.GetSplatCount(), 2u);
    EXPECT_EQ(gaussianSplat.GetBounds().GetMin(), Vector3(-1.0f, -2.0f, -3.0f));
    EXPECT_EQ(gaussianSplat.GetBounds().GetMax(), Vector3(4.0f, 5.0f, 6.0f));
    ASSERT_NE(gaussianSplat.FindSection(GaussianSplatSectionType::Positions), nullptr);
    EXPECT_EQ(gaussianSplat.GetPayloadSize(), 24u);
    EXPECT_NE(gaussianSplat.GetSectionData(GaussianSplatSectionType::Positions), nullptr);
}

TEST(GaussianSplat, GetSHOrderUsesSHSectionStride) {
    GaussianSplat gaussianSplat;

    GaussianSplatMetadata metadata;
    metadata.splatCount = 1u;

    XCEngine::Containers::Array<GaussianSplatSection> sections;
    sections.PushBack(GaussianSplatSection{
        GaussianSplatSectionType::SH,
        GaussianSplatSectionFormat::SHFloat32,
        0u,
        96u,
        1u,
        96u
    });

    XCEngine::Containers::Array<XCEngine::Core::uint8> payload;
    payload.Resize(96u);

    ASSERT_TRUE(gaussianSplat.CreateOwned(metadata, std::move(sections), std::move(payload)));
    EXPECT_EQ(gaussianSplat.GetSHOrder(), 2u);
}

TEST(GaussianSplat, RejectsInvalidSectionLayout) {
    GaussianSplat gaussianSplat;

    GaussianSplatMetadata metadata;
    metadata.splatCount = 1u;

    XCEngine::Containers::Array<GaussianSplatSection> sections;
    sections.PushBack(GaussianSplatSection{
        GaussianSplatSectionType::Positions,
        GaussianSplatSectionFormat::VectorFloat32,
        16u,
        16u,
        1u,
        12u
    });

    XCEngine::Containers::Array<XCEngine::Core::uint8> payload;
    payload.Resize(24u);

    EXPECT_FALSE(gaussianSplat.CreateOwned(metadata, std::move(sections), std::move(payload)));
}

} // namespace