#include <algorithm>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <memory>
#include <stdexcept>
#include <vector>

#if defined(__INTELLISENSE__) || !defined(USE_CPP20_MODULES)
#	include <vulkan/vulkan_raii.hpp>
#else
import vulkan_hpp;
#endif

#define GLFW_INCLUDE_VULKAN        // REQUIRED only for GLFW CreateWindowSurface.
#include <GLFW/glfw3.h>

constexpr uint32_t WIDTH  = 800;
constexpr uint32_t HEIGHT = 600;

const std::vector<char const *> validationLayers = {
    "VK_LAYER_KHRONOS_validation"};

#ifdef NDEBUG
constexpr bool enableValidationLayers = false;
#else
constexpr bool enableValidationLayers = true;
#endif

class HelloTriangleApplication
{
  public:
	void run()
	{
		initWindow();
		initVulkan();
		mainLoop();
		cleanup();
	}

  private:
	GLFWwindow                      *window = nullptr;
	vk::raii::Context                context;
	vk::raii::Instance               instance       = nullptr;
	vk::raii::DebugUtilsMessengerEXT debugMessenger = nullptr;
	vk::raii::SurfaceKHR             surface        = nullptr;
	vk::raii::PhysicalDevice         physicalDevice = nullptr;
	vk::raii::Device                 device         = nullptr;
	vk::raii::Queue                  queue          = nullptr;

	std::vector<const char *> requiredDeviceExtension = {
	    vk::KHRSwapchainExtensionName};

	void initWindow()
	{
		glfwInit();

		glfwWindowHint(GLFW_CLIENT_API, GLFW_NO_API);
		glfwWindowHint(GLFW_RESIZABLE, GLFW_FALSE);

		window = glfwCreateWindow(WIDTH, HEIGHT, "Vulkan", nullptr, nullptr);
	}

	void initVulkan()
	{
		createInstance();
		setupDebugMessenger();
		createSurface();
		pickPhysicalDevice();
		createLogicalDevice();
	}

	void mainLoop()
	{
		while (!glfwWindowShouldClose(window))
		{
			glfwPollEvents();
		}
	}

	void cleanup()
	{
		glfwDestroyWindow(window);

		glfwTerminate();
	}

	void createInstance()
	{
		constexpr vk::ApplicationInfo appInfo{.pApplicationName   = "Hello Triangle",
		                                      .applicationVersion = VK_MAKE_VERSION(1, 0, 0),
		                                      .pEngineName        = "No Engine",
		                                      .engineVersion      = VK_MAKE_VERSION(1, 0, 0),
		                                      .apiVersion         = vk::ApiVersion14};

		// Get the required layers
		std::vector<char const *> requiredLayers;
		if (enableValidationLayers)
		{
			requiredLayers.assign(validationLayers.begin(), validationLayers.end());
		}

		// Check if the required layers are supported by the Vulkan implementation.
		auto layerProperties    = context.enumerateInstanceLayerProperties();
		auto unsupportedLayerIt = std::ranges::find_if(requiredLayers,
		                                               [&layerProperties](auto const &requiredLayer) {
			                                               return std::ranges::none_of(layerProperties,
			                                                                           [requiredLayer](auto const &layerProperty) { return strcmp(layerProperty.layerName, requiredLayer) == 0; });
		                                               });
		if (unsupportedLayerIt != requiredLayers.end())
		{
			throw std::runtime_error("Required layer not supported: " + std::string(*unsupportedLayerIt));
		}

		// Get the required extensions.
		auto requiredExtensions = getRequiredInstanceExtensions();

		// Check if the required extensions are supported by the Vulkan implementation.
		auto extensionProperties = context.enumerateInstanceExtensionProperties();
		auto unsupportedPropertyIt =
		    std::ranges::find_if(requiredExtensions,
		                         [&extensionProperties](auto const &requiredExtension) {
			                         return std::ranges::none_of(extensionProperties,
			                                                     [requiredExtension](auto const &extensionProperty) { return strcmp(extensionProperty.extensionName, requiredExtension) == 0; });
		                         });
		if (unsupportedPropertyIt != requiredExtensions.end())
		{
			throw std::runtime_error("Required extension not supported: " + std::string(*unsupportedPropertyIt));
		}

		vk::InstanceCreateInfo createInfo{.pApplicationInfo        = &appInfo,
		                                  .enabledLayerCount       = static_cast<uint32_t>(requiredLayers.size()),
		                                  .ppEnabledLayerNames     = requiredLayers.data(),
		                                  .enabledExtensionCount   = static_cast<uint32_t>(requiredExtensions.size()),
		                                  .ppEnabledExtensionNames = requiredExtensions.data()};
		instance = vk::raii::Instance(context, createInfo);
	}

	void setupDebugMessenger()
	{
		if (!enableValidationLayers)
			return;

		vk::DebugUtilsMessageSeverityFlagsEXT severityFlags(vk::DebugUtilsMessageSeverityFlagBitsEXT::eWarning |
		                                                    vk::DebugUtilsMessageSeverityFlagBitsEXT::eError);
		vk::DebugUtilsMessageTypeFlagsEXT     messageTypeFlags(
		    vk::DebugUtilsMessageTypeFlagBitsEXT::eGeneral | vk::DebugUtilsMessageTypeFlagBitsEXT::ePerformance | vk::DebugUtilsMessageTypeFlagBitsEXT::eValidation);
		vk::DebugUtilsMessengerCreateInfoEXT debugUtilsMessengerCreateInfoEXT{.messageSeverity = severityFlags,
		                                                                      .messageType     = messageTypeFlags,
		                                                                      .pfnUserCallback = &debugCallback};
		debugMessenger = instance.createDebugUtilsMessengerEXT(debugUtilsMessengerCreateInfoEXT);
	}

	void createSurface()
	{
		VkSurfaceKHR _surface;
		if (glfwCreateWindowSurface(*instance, window, nullptr, &_surface) != 0)
		{
			throw std::runtime_error("failed to create window surface!");
		}
		surface = vk::raii::SurfaceKHR(instance, _surface);
	}

	bool isDeviceSuitable(vk::raii::PhysicalDevice const &physicalDevice)
	{
		// Check if the physicalDevice supports the Vulkan 1.3 API version
		bool supportsVulkan1_3 = physicalDevice.getProperties().apiVersion >= VK_API_VERSION_1_3;

		// Check if any of the queue families support graphics operations
		auto queueFamilies    = physicalDevice.getQueueFamilyProperties();
		bool supportsGraphics = std::ranges::any_of(queueFamilies, [](auto const &qfp) { return !!(qfp.queueFlags & vk::QueueFlagBits::eGraphics); });

		// Check if all required physicalDevice extensions are available
		auto availableDeviceExtensions = physicalDevice.enumerateDeviceExtensionProperties();
		bool supportsAllRequiredExtensions =
		    std::ranges::all_of(requiredDeviceExtension,
		                        [&availableDeviceExtensions](auto const &requiredDeviceExtension) {
			                        return std::ranges::any_of(availableDeviceExtensions,
			                                                   [requiredDeviceExtension](auto const &availableDeviceExtension) { return strcmp(availableDeviceExtension.extensionName, requiredDeviceExtension) == 0; });
		                        });

		// Check if the physicalDevice supports the required features
		auto features                 = physicalDevice.template getFeatures2<vk::PhysicalDeviceFeatures2,
		                                                                     vk::PhysicalDeviceVulkan11Features,
		                                                                     vk::PhysicalDeviceVulkan13Features,
		                                                                     vk::PhysicalDeviceExtendedDynamicStateFeaturesEXT>();
		bool supportsRequiredFeatures = features.template get<vk::PhysicalDeviceVulkan11Features>().shaderDrawParameters &&
		                                features.template get<vk::PhysicalDeviceVulkan13Features>().dynamicRendering &&
		                                features.template get<vk::PhysicalDeviceExtendedDynamicStateFeaturesEXT>().extendedDynamicState;

		// Return true if the physicalDevice meets all the criteria
		return supportsVulkan1_3 && supportsGraphics && supportsAllRequiredExtensions && supportsRequiredFeatures;
	}

	void pickPhysicalDevice()
	{
		std::vector<vk::raii::PhysicalDevice> physicalDevices = instance.enumeratePhysicalDevices();
		auto const                            devIter         = std::ranges::find_if(physicalDevices, [&](auto const &physicalDevice) { return isDeviceSuitable(physicalDevice); });
		if (devIter == physicalDevices.end())
		{
			throw std::runtime_error("failed to find a suitable GPU!");
		}
		physicalDevice = *devIter;
	}

	void createLogicalDevice()
	{
		std::vector<vk::QueueFamilyProperties> queueFamilyProperties = physicalDevice.getQueueFamilyProperties();

		// get the first index into queueFamilyProperties which supports both graphics and present
		uint32_t queueIndex = ~0;
		for (uint32_t qfpIndex = 0; qfpIndex < queueFamilyProperties.size(); qfpIndex++)
		{
			if ((queueFamilyProperties[qfpIndex].queueFlags & vk::QueueFlagBits::eGraphics) &&
			    physicalDevice.getSurfaceSupportKHR(qfpIndex, *surface))
			{
				// found a queue family that supports both graphics and present
				queueIndex = qfpIndex;
				break;
			}
		}
		if (queueIndex == ~0)
		{
			throw std::runtime_error("Could not find a queue for graphics and present -> terminating");
		}

		// query for Vulkan 1.3 features
		vk::StructureChain<vk::PhysicalDeviceFeatures2,
		                   vk::PhysicalDeviceVulkan11Features,
		                   vk::PhysicalDeviceVulkan13Features,
		                   vk::PhysicalDeviceExtendedDynamicStateFeaturesEXT>
		    featureChain = {
		        {},                                    // vk::PhysicalDeviceFeatures2
		        {.shaderDrawParameters = true},        // vk::PhysicalDeviceVulkan11Features
		        {.dynamicRendering = true},            // vk::PhysicalDeviceVulkan13Features
		        {.extendedDynamicState = true}         // vk::PhysicalDeviceExtendedDynamicStateFeaturesEXT
		    };

		// create a Device
		float                     queuePriority = 0.5f;
		vk::DeviceQueueCreateInfo deviceQueueCreateInfo{.queueFamilyIndex = queueIndex, .queueCount = 1, .pQueuePriorities = &queuePriority};
		vk::DeviceCreateInfo      deviceCreateInfo{.pNext                   = &featureChain.get<vk::PhysicalDeviceFeatures2>(),
		                                           .queueCreateInfoCount    = 1,
		                                           .pQueueCreateInfos       = &deviceQueueCreateInfo,
		                                           .enabledExtensionCount   = static_cast<uint32_t>(requiredDeviceExtension.size()),
		                                           .ppEnabledExtensionNames = requiredDeviceExtension.data()};

		device = vk::raii::Device(physicalDevice, deviceCreateInfo);
		queue  = vk::raii::Queue(device, queueIndex, 0);
	}

	std::vector<const char *> getRequiredInstanceExtensions()
	{
		uint32_t glfwExtensionCount = 0;
		auto     glfwExtensions     = glfwGetRequiredInstanceExtensions(&glfwExtensionCount);

		std::vector extensions(glfwExtensions, glfwExtensions + glfwExtensionCount);
		if (enableValidationLayers)
		{
			extensions.push_back(vk::EXTDebugUtilsExtensionName);
		}

		return extensions;
	}

	static VKAPI_ATTR vk::Bool32 VKAPI_CALL debugCallback(vk::DebugUtilsMessageSeverityFlagBitsEXT severity, vk::DebugUtilsMessageTypeFlagsEXT type, const vk::DebugUtilsMessengerCallbackDataEXT *pCallbackData, void *)
	{
		if (severity == vk::DebugUtilsMessageSeverityFlagBitsEXT::eError || severity == vk::DebugUtilsMessageSeverityFlagBitsEXT::eWarning)
		{
			std::cerr << "validation layer: type " << to_string(type) << " msg: " << pCallbackData->pMessage << std::endl;
		}

		return vk::False;
	}
};

int main()
{
	try
	{
		HelloTriangleApplication app;
		app.run();
	}
	catch (const std::exception &e)
	{
		std::cerr << e.what() << std::endl;
		return EXIT_FAILURE;
	}

	return EXIT_SUCCESS;
}