#include <gtest/gtest.h>
#include <XCEngine/Resources/Material/MaterialLoader.h>
#include <XCEngine/Core/Asset/ResourceManager.h>
#include <XCEngine/Core/Asset/ResourceTypes.h>
#include <XCEngine/Core/Containers/Array.h>

#include <cstdio>
#include <filesystem>
#include <fstream>

using namespace XCEngine::Resources;
using namespace XCEngine::Containers;

namespace {

TEST(MaterialLoader, GetResourceType) {
    MaterialLoader loader;
    EXPECT_EQ(loader.GetResourceType(), ResourceType::Material);
}

TEST(MaterialLoader, GetSupportedExtensions) {
    MaterialLoader loader;
    auto extensions = loader.GetSupportedExtensions();
    EXPECT_GE(extensions.Size(), 1u);
}

TEST(MaterialLoader, CanLoad) {
    MaterialLoader loader;
    EXPECT_TRUE(loader.CanLoad("test.mat"));
    EXPECT_TRUE(loader.CanLoad("test.json"));
    EXPECT_FALSE(loader.CanLoad("test.txt"));
    EXPECT_FALSE(loader.CanLoad("test.png"));
}

TEST(MaterialLoader, LoadInvalidPath) {
    MaterialLoader loader;
    LoadResult result = loader.Load("invalid/path/material.mat");
    EXPECT_FALSE(result);
}

TEST(MaterialLoader, ResourceManagerRegistersMaterialAndShaderLoaders) {
    ResourceManager& manager = ResourceManager::Get();
    manager.Initialize();

    EXPECT_NE(manager.GetLoader(ResourceType::Material), nullptr);
    EXPECT_NE(manager.GetLoader(ResourceType::Shader), nullptr);

    manager.Shutdown();
}

TEST(MaterialLoader, LoadValidMaterialParsesRenderMetadata) {
    const std::filesystem::path shaderPath =
        std::filesystem::current_path() / "material_loader_valid_shader.hlsl";
    const std::filesystem::path materialPath =
        std::filesystem::current_path() / "material_loader_valid.material";

    {
        std::ofstream shaderFile(shaderPath);
        ASSERT_TRUE(shaderFile.is_open());
        shaderFile << "float4 MainPS() : SV_TARGET { return float4(1, 1, 1, 1); }";
    }

    {
        std::ofstream materialFile(materialPath);
        ASSERT_TRUE(materialFile.is_open());
        materialFile << "{\n";
        materialFile << "  \"shader\": \"" << shaderPath.generic_string() << "\",\n";
        materialFile << "  \"renderQueue\": \"Transparent\",\n";
        materialFile << "  \"shaderPass\": \"ForwardLit\",\n";
        materialFile << "  \"tags\": {\n";
        materialFile << "    \"LightMode\": \"ForwardBase\",\n";
        materialFile << "    \"RenderType\": \"Transparent\"\n";
        materialFile << "  }\n";
        materialFile << "}";
    }

    MaterialLoader loader;
    LoadResult result = loader.Load(materialPath.string().c_str());
    ASSERT_TRUE(result);
    ASSERT_NE(result.resource, nullptr);

    Material* material = static_cast<Material*>(result.resource);
    ASSERT_NE(material, nullptr);
    EXPECT_TRUE(material->IsValid());
    EXPECT_NE(material->GetShader(), nullptr);
    EXPECT_EQ(material->GetRenderQueue(), static_cast<XCEngine::Core::int32>(MaterialRenderQueue::Transparent));
    EXPECT_EQ(material->GetShaderPass(), "ForwardLit");
    EXPECT_EQ(material->GetTag("LightMode"), "ForwardBase");
    EXPECT_EQ(material->GetTag("RenderType"), "Transparent");

    delete material;
    std::remove(materialPath.string().c_str());
    std::remove(shaderPath.string().c_str());
}

TEST(MaterialLoader, RejectsUnknownRenderQueueName) {
    const std::filesystem::path materialPath =
        std::filesystem::current_path() / "material_loader_invalid_queue.material";

    {
        std::ofstream materialFile(materialPath);
        ASSERT_TRUE(materialFile.is_open());
        materialFile << "{ \"renderQueue\": \"NotAQueue\" }";
    }

    MaterialLoader loader;
    LoadResult result = loader.Load(materialPath.string().c_str());
    EXPECT_FALSE(result);

    std::remove(materialPath.string().c_str());
}

} // namespace