#include "VulkanInstanceManager.h"

#include "Logger.h"

VulkanInstanceManager::VulkanInstanceManager()
{
}

VulkanInstanceManager::~VulkanInstanceManager()
{
	Cleanup();
}

VulkanInstanceManager::VulkanInstanceManager(VulkanInstanceManager&& Other) noexcept
	: Instance(Other.Instance), bValidationEnabled(Other.bValidationEnabled), bVerboseLogging(Other.bVerboseLogging), VkDebugManager(std::move(Other.VkDebugManager))
{
	Other.Instance = VK_NULL_HANDLE;
	Other.bValidationEnabled = false;
	Other.bVerboseLogging = false;
}

VulkanInstanceManager& VulkanInstanceManager::operator=(VulkanInstanceManager&& Other) noexcept
{
	if (this != &Other)
	{
		Cleanup();
		Instance = Other.Instance;
		bValidationEnabled = Other.bValidationEnabled;
		bVerboseLogging = Other.bVerboseLogging;
		VkDebugManager = std::move(Other.VkDebugManager);

		Other.Instance = VK_NULL_HANDLE;
	}

	return *this;
}
void VulkanInstanceManager::Initialize(const FVulkanConfig& Config)
{
	if (IsInitialized())
	{
		Log::Warning("Already Initialized.");
		return;
	}

	bValidationEnabled = Config.bValidationEnabled;
	bVerboseLogging = Config.bVerboseLogging;

	if (bValidationEnabled)
	{
		Log::Info("DebugManager created with validation enabled.");
		VkDebugManager = std::make_unique<VulkanDebugManager>();
	}

	CreateInstance();

	if (VkDebugManager)
	{
		VkDebugManager->Initialize(Instance);
	}

	VkDeviceManager = std::make_unique<VulkanDeviceManager>();
	VkDeviceManager->Initialize(Instance);
}

void VulkanInstanceManager::Cleanup()
{
	if (!IsInitialized())
	{
		Log::Warning("Not initialized.");
		return;
	}

	if (VkDebugManager)
	{
		VkDebugManager->Cleanup();
	}

	if (VkDeviceManager)
	{
		VkDeviceManager->Cleanup();
	}

	vkDestroyInstance(Instance, nullptr);
	Instance = VK_NULL_HANDLE;
}

std::vector<const char*> VulkanInstanceManager::GetRequiredExtensions()
{
	uint32_t	 GlfwExtensionCount = 0;
	const char** GlfwExtensions;
	GlfwExtensions = glfwGetRequiredInstanceExtensions(&GlfwExtensionCount);

	std::vector<const char*> Extensions(GlfwExtensions, GlfwExtensions + GlfwExtensionCount);

	if (VkDebugManager)
	{
		Extensions.push_back(VK_EXT_DEBUG_UTILS_EXTENSION_NAME);
	}

	return Extensions;
}

bool VulkanInstanceManager::CheckValidationLayerSupport()
{
	uint32_t LayerCount;
	vkEnumerateInstanceLayerProperties(&LayerCount, nullptr);

	std::vector<VkLayerProperties> AvailableLayers(LayerCount);
	vkEnumerateInstanceLayerProperties(&LayerCount, AvailableLayers.data());

	for (const char* LayerName : ValidationLayers)
	{
		bool bLayerFound = false;

		for (const auto& LayerProperties : AvailableLayers)
		{
			if (strcmp(LayerName, LayerProperties.layerName) == 0)
			{
				bLayerFound = true;
				break;
			}
		}

		if (!bLayerFound)
		{
			return false;
		}
	}

	return true;
}

void VulkanInstanceManager::CreateInstance()
{
	Log::Info("Creating Vulkan instance.");

	if (bValidationEnabled && !CheckValidationLayerSupport())
	{
		Log::Error("Validation layers requested, but not available!");
	}

	VkApplicationInfo AppInfo{};
	AppInfo.sType = VK_STRUCTURE_TYPE_APPLICATION_INFO;
	AppInfo.pApplicationName = "Hello Triangle";
	AppInfo.applicationVersion = VK_MAKE_VERSION(1, 0, 0);
	AppInfo.pEngineName = "No Engine";
	AppInfo.engineVersion = VK_MAKE_VERSION(1, 0, 0);
	AppInfo.apiVersion = VK_API_VERSION_1_0;

	VkInstanceCreateInfo CreateInfo{};
	CreateInfo.sType = VK_STRUCTURE_TYPE_INSTANCE_CREATE_INFO;
	CreateInfo.pApplicationInfo = &AppInfo;

	auto Extensions = GetRequiredExtensions();
	CreateInfo.enabledExtensionCount = static_cast<uint32_t>(Extensions.size());
	CreateInfo.ppEnabledExtensionNames = Extensions.data();

	if (VkDebugManager)
	{
		VkDebugUtilsMessengerCreateInfoEXT debugCreateInfo{};
		CreateInfo.enabledLayerCount = static_cast<uint32_t>(ValidationLayers.size());
		CreateInfo.ppEnabledLayerNames = ValidationLayers.data();

		VkDebugManager->PopulateDebugMessengerCreateInfo(debugCreateInfo);
		CreateInfo.pNext = (VkDebugUtilsMessengerCreateInfoEXT*)&debugCreateInfo;
	}
	else
	{
		CreateInfo.enabledLayerCount = 0;
		CreateInfo.pNext = nullptr;
	}

	if (vkCreateInstance(&CreateInfo, nullptr, &Instance) != VK_SUCCESS)
	{
		Log::Error("Failed to create instance!");
	}
}