#include <gtest/gtest.h>

#include <XCEngine/Rendering/Passes/BuiltinVectorFullscreenPass.h>
#include <XCEngine/Rendering/Planning/FullscreenPassFactory.h>
#include <XCEngine/Resources/BuiltinResources.h>

namespace {

void ExpectVector4Eq(
    const XCEngine::Math::Vector4& actual,
    const XCEngine::Math::Vector4& expected) {
    EXPECT_FLOAT_EQ(actual.x, expected.x);
    EXPECT_FLOAT_EQ(actual.y, expected.y);
    EXPECT_FLOAT_EQ(actual.z, expected.z);
    EXPECT_FLOAT_EQ(actual.w, expected.w);
}

} // namespace

TEST(FullscreenPassFactory_Test, BuildsColorScaleDescriptorIntoBuiltinVectorFullscreenPass) {
    const XCEngine::Math::Vector4 payload(1.1f, 0.95f, 0.9f, 1.0f);
    const XCEngine::Rendering::FullscreenPassStack fullscreenPasses = {
        XCEngine::Rendering::FullscreenPassDesc::MakeColorScale(payload)
    };

    std::unique_ptr<XCEngine::Rendering::RenderPassSequence> sequence =
        XCEngine::Rendering::BuildFullscreenPassSequence(fullscreenPasses);
    ASSERT_NE(sequence, nullptr);
    ASSERT_EQ(sequence->GetPassCount(), 1u);

    auto* pass = dynamic_cast<XCEngine::Rendering::Passes::BuiltinVectorFullscreenPass*>(
        sequence->GetPass(0u));
    ASSERT_NE(pass, nullptr);
    ExpectVector4Eq(pass->GetVectorPayload(), payload);
    EXPECT_EQ(
        pass->GetShaderPath(),
        XCEngine::Resources::GetBuiltinColorScalePostProcessShaderPath());
    EXPECT_EQ(
        pass->GetPreferredPassName(),
        XCEngine::Containers::String("ColorScale"));
}

TEST(FullscreenPassFactory_Test, BuildsShaderVectorDescriptorIntoBuiltinVectorFullscreenPass) {
    const XCEngine::Containers::String shaderPath(
        "builtin://shaders/color-scale-post-process");
    const XCEngine::Containers::String passName("ColorScale");
    const XCEngine::Math::Vector4 payload(0.95f, 1.05f, 1.1f, 1.0f);
    const XCEngine::Rendering::FullscreenPassStack fullscreenPasses = {
        XCEngine::Rendering::FullscreenPassDesc::MakeShaderVector(
            shaderPath,
            payload,
            passName)
    };

    std::unique_ptr<XCEngine::Rendering::RenderPassSequence> sequence =
        XCEngine::Rendering::BuildFullscreenPassSequence(fullscreenPasses);
    ASSERT_NE(sequence, nullptr);
    ASSERT_EQ(sequence->GetPassCount(), 1u);

    auto* pass = dynamic_cast<XCEngine::Rendering::Passes::BuiltinVectorFullscreenPass*>(
        sequence->GetPass(0u));
    ASSERT_NE(pass, nullptr);
    ExpectVector4Eq(pass->GetVectorPayload(), payload);
    EXPECT_EQ(pass->GetShaderPath(), shaderPath);
    EXPECT_EQ(pass->GetPreferredPassName(), passName);
}

TEST(FullscreenPassFactory_Test, IgnoresInvalidShaderVectorDescriptor) {
    XCEngine::Rendering::FullscreenPassStack fullscreenPasses = {
        XCEngine::Rendering::FullscreenPassDesc::MakeShaderVector(
            XCEngine::Containers::String(),
            XCEngine::Math::Vector4::One())
    };

    std::unique_ptr<XCEngine::Rendering::RenderPassSequence> sequence =
        XCEngine::Rendering::BuildFullscreenPassSequence(fullscreenPasses);
    EXPECT_EQ(sequence, nullptr);
}