#include "fixtures/RHITestFixture.h"
#include "XCEngine/RHI/RHISampler.h"
#include "XCEngine/RHI/OpenGL/OpenGLSampler.h"
#include <glad/glad.h>

using namespace XCEngine::RHI;

TEST_P(RHITestFixture, Sampler_Create) {
    SamplerDesc desc = {};
    desc.filter = static_cast<uint32_t>(FilterMode::Linear);
    desc.addressU = static_cast<uint32_t>(TextureAddressMode::Wrap);
    desc.addressV = static_cast<uint32_t>(TextureAddressMode::Wrap);
    desc.addressW = static_cast<uint32_t>(TextureAddressMode::Wrap);
    desc.mipLodBias = 0.0f;
    desc.maxAnisotropy = 16;
    desc.comparisonFunc = static_cast<uint32_t>(ComparisonFunc::Less);
    desc.borderColorR = 0.0f;
    desc.borderColorG = 0.0f;
    desc.borderColorB = 0.0f;
    desc.borderColorA = 0.0f;
    desc.minLod = 0.0f;
    desc.maxLod = 100.0f;

    RHISampler* sampler = GetDevice()->CreateSampler(desc);
    ASSERT_NE(sampler, nullptr);

    sampler->Shutdown();
    delete sampler;
}

TEST_P(RHITestFixture, Sampler_Bind_Unbind) {
    SamplerDesc desc = {};
    desc.filter = static_cast<uint32_t>(FilterMode::Linear);
    desc.addressU = static_cast<uint32_t>(TextureAddressMode::Wrap);
    desc.addressV = static_cast<uint32_t>(TextureAddressMode::Wrap);
    desc.addressW = static_cast<uint32_t>(TextureAddressMode::Wrap);

    RHISampler* sampler = GetDevice()->CreateSampler(desc);
    ASSERT_NE(sampler, nullptr);

    sampler->Bind(0);
    sampler->Unbind(0);

    sampler->Shutdown();
    delete sampler;
}

TEST_P(RHITestFixture, Sampler_GetID) {
    SamplerDesc desc = {};
    desc.filter = static_cast<uint32_t>(FilterMode::Linear);
    desc.addressU = static_cast<uint32_t>(TextureAddressMode::Wrap);
    desc.addressV = static_cast<uint32_t>(TextureAddressMode::Wrap);
    desc.addressW = static_cast<uint32_t>(TextureAddressMode::Wrap);

    RHISampler* sampler = GetDevice()->CreateSampler(desc);
    ASSERT_NE(sampler, nullptr);

    unsigned int id = sampler->GetID();
    EXPECT_GE(id, 0u);

    sampler->Shutdown();
    delete sampler;
}

TEST_P(RHITestFixture, Sampler_GetNativeHandle) {
    SamplerDesc desc = {};
    desc.filter = static_cast<uint32_t>(FilterMode::Linear);
    desc.addressU = static_cast<uint32_t>(TextureAddressMode::Wrap);
    desc.addressV = static_cast<uint32_t>(TextureAddressMode::Wrap);
    desc.addressW = static_cast<uint32_t>(TextureAddressMode::Wrap);

    RHISampler* sampler = GetDevice()->CreateSampler(desc);
    ASSERT_NE(sampler, nullptr);

    EXPECT_NE(sampler->GetNativeHandle(), nullptr);

    sampler->Shutdown();
    delete sampler;
}

TEST_P(RHITestFixture, Sampler_OpenGLHonorsSamplerDesc) {
    if (GetBackendType() != RHIType::OpenGL) {
        GTEST_SKIP() << "OpenGL-specific sampler parameter verification";
    }

    SamplerDesc desc = {};
    desc.filter = static_cast<uint32_t>(FilterMode::ComparisonAnisotropic);
    desc.addressU = static_cast<uint32_t>(TextureAddressMode::Clamp);
    desc.addressV = static_cast<uint32_t>(TextureAddressMode::Mirror);
    desc.addressW = static_cast<uint32_t>(TextureAddressMode::Border);
    desc.maxAnisotropy = 8;
    desc.comparisonFunc = static_cast<uint32_t>(ComparisonFunc::GreaterEqual);
    desc.minLod = 1.0f;
    desc.maxLod = 4.0f;

    RHISampler* sampler = GetDevice()->CreateSampler(desc);
    ASSERT_NE(sampler, nullptr);

    const GLuint samplerId = static_cast<OpenGLSampler*>(sampler)->GetID();

    GLint value = 0;
    glGetSamplerParameteriv(samplerId, GL_TEXTURE_WRAP_S, &value);
    EXPECT_EQ(value, GL_CLAMP_TO_EDGE);
    glGetSamplerParameteriv(samplerId, GL_TEXTURE_WRAP_T, &value);
    EXPECT_EQ(value, GL_MIRRORED_REPEAT);
    glGetSamplerParameteriv(samplerId, GL_TEXTURE_WRAP_R, &value);
    EXPECT_EQ(value, GL_CLAMP_TO_BORDER);
    glGetSamplerParameteriv(samplerId, GL_TEXTURE_MIN_FILTER, &value);
    EXPECT_EQ(value, GL_LINEAR_MIPMAP_LINEAR);
    glGetSamplerParameteriv(samplerId, GL_TEXTURE_MAG_FILTER, &value);
    EXPECT_EQ(value, GL_LINEAR);
    glGetSamplerParameteriv(samplerId, GL_TEXTURE_COMPARE_MODE, &value);
    EXPECT_EQ(value, GL_COMPARE_REF_TO_TEXTURE);
    glGetSamplerParameteriv(samplerId, GL_TEXTURE_COMPARE_FUNC, &value);
    EXPECT_EQ(value, GL_GEQUAL);

    GLfloat floatValue = 0.0f;
    glGetSamplerParameterfv(samplerId, GL_TEXTURE_MAX_ANISOTROPY, &floatValue);
    EXPECT_GE(floatValue, 8.0f);
    glGetSamplerParameterfv(samplerId, GL_TEXTURE_MIN_LOD, &floatValue);
    EXPECT_FLOAT_EQ(floatValue, 1.0f);
    glGetSamplerParameterfv(samplerId, GL_TEXTURE_MAX_LOD, &floatValue);
    EXPECT_FLOAT_EQ(floatValue, 4.0f);

    sampler->Shutdown();
    delete sampler;
}