#include <iostream>
#include <fstream>
#include <stdexcept>
#include <vector>
#include <cstring>
#include <cstdlib>
#include <memory>
#include <algorithm>
#include <limits>
#include <array>
#include <chrono>

#ifdef __INTELLISENSE__
#include <vulkan/vulkan_raii.hpp>
#else
import vulkan_hpp;
#endif

#include <vulkan/vk_platform.h>

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

#define GLM_FORCE_RADIANS
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>

constexpr uint32_t WIDTH = 800;
constexpr uint32_t HEIGHT = 600;
constexpr int MAX_FRAMES_IN_FLIGHT = 2;

const std::vector validationLayers = {
    "VK_LAYER_KHRONOS_validation"
};

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

struct Vertex {
    glm::vec2 pos;
    glm::vec3 color;

    static vk::VertexInputBindingDescription getBindingDescription() {
        return { 0, sizeof(Vertex), vk::VertexInputRate::eVertex };
    }

    static std::array<vk::VertexInputAttributeDescription, 2> getAttributeDescriptions() {
        return {
            vk::VertexInputAttributeDescription( 0, 0, vk::Format::eR32G32Sfloat, offsetof(Vertex, pos) ),
            vk::VertexInputAttributeDescription( 1, 0, vk::Format::eR32G32B32Sfloat, offsetof(Vertex, color) )
        };
    }
};

struct UniformBufferObject {
    glm::mat4 model;
    glm::mat4 view;
    glm::mat4 proj;
};

const std::vector<Vertex> vertices = {
    {{-0.5f, -0.5f}, {1.0f, 0.0f, 0.0f}},
    {{0.5f, -0.5f}, {0.0f, 1.0f, 0.0f}},
    {{0.5f, 0.5f}, {0.0f, 0.0f, 1.0f}},
    {{-0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}}
};

const std::vector<uint16_t> indices = {
    0, 1, 2, 2, 3, 0
};

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;
    uint32_t                         queueIndex     = ~0;
    vk::raii::Queue                  queue          = nullptr;

    vk::raii::SwapchainKHR swapChain = nullptr;
    std::vector<vk::Image> swapChainImages;
    vk::Format swapChainImageFormat = vk::Format::eUndefined;
    vk::Extent2D swapChainExtent;
    std::vector<vk::raii::ImageView> swapChainImageViews;

    vk::raii::DescriptorSetLayout descriptorSetLayout = nullptr;
    vk::raii::PipelineLayout pipelineLayout = nullptr;
    vk::raii::Pipeline graphicsPipeline = nullptr;

    vk::raii::Buffer vertexBuffer = nullptr;
    vk::raii::DeviceMemory vertexBufferMemory = nullptr;
    vk::raii::Buffer indexBuffer = nullptr;
    vk::raii::DeviceMemory indexBufferMemory = nullptr;

    std::vector<vk::raii::Buffer> uniformBuffers;
    std::vector<vk::raii::DeviceMemory> uniformBuffersMemory;
    std::vector<void*> uniformBuffersMapped;

    vk::raii::CommandPool commandPool = nullptr;
    std::vector<vk::raii::CommandBuffer> commandBuffers;

    std::vector<vk::raii::Semaphore> presentCompleteSemaphore;
    std::vector<vk::raii::Semaphore> renderFinishedSemaphore;
    std::vector<vk::raii::Fence> inFlightFences;
    uint32_t semaphoreIndex = 0;
    uint32_t currentFrame = 0;

    bool framebufferResized = false;

    std::vector<const char*> requiredDeviceExtension = {
        vk::KHRSwapchainExtensionName,
        vk::KHRSpirv14ExtensionName,
        vk::KHRSynchronization2ExtensionName,
        vk::KHRCreateRenderpass2ExtensionName
    };

    void initWindow() {
        glfwInit();

        glfwWindowHint(GLFW_CLIENT_API, GLFW_NO_API);

        window = glfwCreateWindow(WIDTH, HEIGHT, "Vulkan", nullptr, nullptr);
        glfwSetWindowUserPointer(window, this);
        glfwSetFramebufferSizeCallback(window, framebufferResizeCallback);
    }

    static void framebufferResizeCallback(GLFWwindow* window, int width, int height) {
        auto app = static_cast<HelloTriangleApplication*>(glfwGetWindowUserPointer(window));
        app->framebufferResized = true;
    }

    void initVulkan() {
        createInstance();
        setupDebugMessenger();
        createSurface();
        pickPhysicalDevice();
        createLogicalDevice();
        createSwapChain();
        createImageViews();
        createDescriptorSetLayout();
        createGraphicsPipeline();
        createCommandPool();
        createVertexBuffer();
        createIndexBuffer();
        createUniformBuffers();
        createCommandBuffers();
        createSyncObjects();
    }

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

        device.waitIdle();
    }

    void cleanupSwapChain() {
        swapChainImageViews.clear();
        swapChain = nullptr;
    }

    void cleanup() {
        glfwDestroyWindow(window);

        glfwTerminate();
    }

    void recreateSwapChain() {
        int width = 0, height = 0;
        glfwGetFramebufferSize(window, &width, &height);
        while (width == 0 || height == 0) {
            glfwGetFramebufferSize(window, &width, &height);
            glfwWaitEvents();
        }

        device.waitIdle();

        cleanupSwapChain();
        createSwapChain();
        createImageViews();
    }

    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();
        for (auto const& requiredLayer : requiredLayers)
        {
            if (std::ranges::none_of(layerProperties,
                                     [requiredLayer](auto const& layerProperty)
                                     { return strcmp(layerProperty.layerName, requiredLayer) == 0; }))
            {
                throw std::runtime_error("Required layer not supported: " + std::string(requiredLayer));
            }
        }

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

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

        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::eVerbose | 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);
    }

    void pickPhysicalDevice() {
        std::vector<vk::raii::PhysicalDevice> devices = instance.enumeratePhysicalDevices();
        const auto                            devIter = std::ranges::find_if(
          devices,
          [&]( auto const & device )
          {
            // Check if the device supports the Vulkan 1.3 API version
            bool supportsVulkan1_3 = device.getProperties().apiVersion >= VK_API_VERSION_1_3;

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

            // Check if all required device extensions are available
            auto availableDeviceExtensions = device.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; } );
                                   } );

            auto features = device.template getFeatures2<vk::PhysicalDeviceFeatures2, vk::PhysicalDeviceVulkan13Features, vk::PhysicalDeviceExtendedDynamicStateFeaturesEXT>();
            bool supportsRequiredFeatures = features.template get<vk::PhysicalDeviceVulkan13Features>().dynamicRendering &&
                                            features.template get<vk::PhysicalDeviceExtendedDynamicStateFeaturesEXT>().extendedDynamicState;

            return supportsVulkan1_3 && supportsGraphics && supportsAllRequiredExtensions && supportsRequiredFeatures;
          } );
        if ( devIter != devices.end() )
        {
            physicalDevice = *devIter;
        }
        else
        {
            throw std::runtime_error( "failed to find a suitable GPU!" );
        }
    }

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

        // get the first index into queueFamilyProperties which supports both graphics and present
        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::PhysicalDeviceVulkan13Features, vk::PhysicalDeviceExtendedDynamicStateFeaturesEXT> featureChain = {
            {},                                                     // vk::PhysicalDeviceFeatures2
            {.synchronization2 = true, .dynamicRendering = true },  // vk::PhysicalDeviceVulkan13Features
            {.extendedDynamicState = true }                         // vk::PhysicalDeviceExtendedDynamicStateFeaturesEXT
        };

        // create a Device
        float                     queuePriority = 0.0f;
        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 );
    }

    void createSwapChain() {
        auto surfaceCapabilities = physicalDevice.getSurfaceCapabilitiesKHR( surface );
        swapChainImageFormat = chooseSwapSurfaceFormat(physicalDevice.getSurfaceFormatsKHR( surface ));
        swapChainExtent = chooseSwapExtent(surfaceCapabilities);
        auto minImageCount = std::max( 3u, surfaceCapabilities.minImageCount );
        minImageCount = ( surfaceCapabilities.maxImageCount > 0 && minImageCount > surfaceCapabilities.maxImageCount ) ? surfaceCapabilities.maxImageCount : minImageCount;
        vk::SwapchainCreateInfoKHR swapChainCreateInfo{
            .surface = surface, .minImageCount = minImageCount,
            .imageFormat = swapChainImageFormat, .imageColorSpace = vk::ColorSpaceKHR::eSrgbNonlinear,
            .imageExtent = swapChainExtent, .imageArrayLayers =1,
            .imageUsage = vk::ImageUsageFlagBits::eColorAttachment, .imageSharingMode = vk::SharingMode::eExclusive,
            .preTransform = surfaceCapabilities.currentTransform, .compositeAlpha = vk::CompositeAlphaFlagBitsKHR::eOpaque,
            .presentMode = chooseSwapPresentMode(physicalDevice.getSurfacePresentModesKHR( surface )),
            .clipped = true };

        swapChain = vk::raii::SwapchainKHR( device, swapChainCreateInfo );
        swapChainImages = swapChain.getImages();
    }

    void createImageViews() {
        vk::ImageViewCreateInfo imageViewCreateInfo{ .viewType = vk::ImageViewType::e2D, .format = swapChainImageFormat,
          .subresourceRange = { vk::ImageAspectFlagBits::eColor, 0, 1, 0, 1 } };
        for ( auto image : swapChainImages )
        {
            imageViewCreateInfo.image = image;
            swapChainImageViews.emplace_back( device, imageViewCreateInfo );
        }
    }

    void createDescriptorSetLayout() {
        vk::DescriptorSetLayoutBinding uboLayoutBinding(0, vk::DescriptorType::eUniformBuffer, 1, vk::ShaderStageFlagBits::eVertex, nullptr);
        vk::DescriptorSetLayoutCreateInfo layoutInfo{ .bindingCount = 1, .pBindings = &uboLayoutBinding };
        descriptorSetLayout = vk::raii::DescriptorSetLayout( device, layoutInfo );
    }

    void createGraphicsPipeline() {
        vk::raii::ShaderModule shaderModule = createShaderModule(readFile("shaders/slang.spv"));

        vk::PipelineShaderStageCreateInfo vertShaderStageInfo{ .stage = vk::ShaderStageFlagBits::eVertex, .module = shaderModule,  .pName = "vertMain" };
        vk::PipelineShaderStageCreateInfo fragShaderStageInfo{ .stage = vk::ShaderStageFlagBits::eFragment, .module = shaderModule, .pName = "fragMain" };
        vk::PipelineShaderStageCreateInfo shaderStages[] = {vertShaderStageInfo, fragShaderStageInfo};

        auto bindingDescription = Vertex::getBindingDescription();
        auto attributeDescriptions = Vertex::getAttributeDescriptions();
        vk::PipelineVertexInputStateCreateInfo vertexInputInfo {  .vertexBindingDescriptionCount =1, .pVertexBindingDescriptions = &bindingDescription,
            .vertexAttributeDescriptionCount = static_cast<uint32_t>(attributeDescriptions.size()), .pVertexAttributeDescriptions = attributeDescriptions.data() };
        vk::PipelineInputAssemblyStateCreateInfo inputAssembly{  .topology = vk::PrimitiveTopology::eTriangleList };
        vk::PipelineViewportStateCreateInfo viewportState{ .viewportCount = 1, .scissorCount = 1 };

        vk::PipelineRasterizationStateCreateInfo rasterizer{  .depthClampEnable = vk::False, .rasterizerDiscardEnable = vk::False,
                                                              .polygonMode = vk::PolygonMode::eFill, .cullMode = vk::CullModeFlagBits::eBack,
                                                              .frontFace = vk::FrontFace::eCounterClockwise, .depthBiasEnable = vk::False,
                                                              .depthBiasSlopeFactor = 1.0f, .lineWidth = 1.0f };

        vk::PipelineMultisampleStateCreateInfo multisampling{.rasterizationSamples = vk::SampleCountFlagBits::e1, .sampleShadingEnable = vk::False};

        vk::PipelineColorBlendAttachmentState colorBlendAttachment{ .blendEnable = vk::False,
            .colorWriteMask = vk::ColorComponentFlagBits::eR | vk::ColorComponentFlagBits::eG | vk::ColorComponentFlagBits::eB | vk::ColorComponentFlagBits::eA
        };

        vk::PipelineColorBlendStateCreateInfo colorBlending{.logicOpEnable = vk::False, .logicOp =  vk::LogicOp::eCopy, .attachmentCount = 1, .pAttachments =  &colorBlendAttachment };

        std::vector dynamicStates = {
            vk::DynamicState::eViewport,
            vk::DynamicState::eScissor
        };
        vk::PipelineDynamicStateCreateInfo dynamicState{ .dynamicStateCount = static_cast<uint32_t>(dynamicStates.size()), .pDynamicStates = dynamicStates.data() };

        vk::PipelineLayoutCreateInfo pipelineLayoutInfo{  .setLayoutCount = 1, .pSetLayouts = &*descriptorSetLayout, .pushConstantRangeCount = 0 };

        pipelineLayout = vk::raii::PipelineLayout( device, pipelineLayoutInfo );

        vk::PipelineRenderingCreateInfo pipelineRenderingCreateInfo{ .colorAttachmentCount = 1, .pColorAttachmentFormats = &swapChainImageFormat };
        vk::GraphicsPipelineCreateInfo pipelineInfo{ .pNext = &pipelineRenderingCreateInfo,
            .stageCount = 2, .pStages = shaderStages,
            .pVertexInputState = &vertexInputInfo, .pInputAssemblyState = &inputAssembly,
            .pViewportState = &viewportState, .pRasterizationState = &rasterizer,
            .pMultisampleState = &multisampling, .pColorBlendState = &colorBlending,
            .pDynamicState = &dynamicState, .layout = pipelineLayout, .renderPass = nullptr };

        graphicsPipeline = vk::raii::Pipeline(device, nullptr, pipelineInfo);
    }

    void createCommandPool() {
        vk::CommandPoolCreateInfo poolInfo{  .flags = vk::CommandPoolCreateFlagBits::eResetCommandBuffer,
                                             .queueFamilyIndex = queueIndex };
        commandPool = vk::raii::CommandPool(device, poolInfo);
    }

    void createVertexBuffer() {
        vk::DeviceSize bufferSize = sizeof(vertices[0]) * vertices.size();
        vk::raii::Buffer stagingBuffer({});
        vk::raii::DeviceMemory stagingBufferMemory({});
        createBuffer(bufferSize, vk::BufferUsageFlagBits::eTransferSrc, vk::MemoryPropertyFlagBits::eHostVisible | vk::MemoryPropertyFlagBits::eHostCoherent, stagingBuffer, stagingBufferMemory);

        void* dataStaging = stagingBufferMemory.mapMemory(0, bufferSize);
        memcpy(dataStaging, vertices.data(), bufferSize);
        stagingBufferMemory.unmapMemory();

        createBuffer(bufferSize, vk::BufferUsageFlagBits::eTransferDst | vk::BufferUsageFlagBits::eVertexBuffer, vk::MemoryPropertyFlagBits::eDeviceLocal, vertexBuffer, vertexBufferMemory);

        copyBuffer(stagingBuffer, vertexBuffer, bufferSize);
    }

    void createIndexBuffer() {
        vk::DeviceSize bufferSize = sizeof(indices[0]) * indices.size();

        vk::raii::Buffer stagingBuffer({});
        vk::raii::DeviceMemory stagingBufferMemory({});
        createBuffer(bufferSize, vk::BufferUsageFlagBits::eTransferSrc, vk::MemoryPropertyFlagBits::eHostVisible | vk::MemoryPropertyFlagBits::eHostCoherent, stagingBuffer, stagingBufferMemory);

        void* data = stagingBufferMemory.mapMemory(0, bufferSize);
        memcpy(data, indices.data(), (size_t) bufferSize);
        stagingBufferMemory.unmapMemory();

        createBuffer(bufferSize, vk::BufferUsageFlagBits::eTransferDst | vk::BufferUsageFlagBits::eIndexBuffer, vk::MemoryPropertyFlagBits::eDeviceLocal, indexBuffer, indexBufferMemory);

        copyBuffer(stagingBuffer, indexBuffer, bufferSize);
   }

    void createUniformBuffers() {
        uniformBuffers.clear();
        uniformBuffersMemory.clear();
        uniformBuffersMapped.clear();

        for (size_t i = 0; i < MAX_FRAMES_IN_FLIGHT; i++) {
            vk::DeviceSize bufferSize = sizeof(UniformBufferObject);
            vk::raii::Buffer buffer({});
            vk::raii::DeviceMemory bufferMem({});
            createBuffer(bufferSize, vk::BufferUsageFlagBits::eUniformBuffer, vk::MemoryPropertyFlagBits::eHostVisible | vk::MemoryPropertyFlagBits::eHostCoherent, buffer, bufferMem);
            uniformBuffers.emplace_back(std::move(buffer));
            uniformBuffersMemory.emplace_back(std::move(bufferMem));
            uniformBuffersMapped.emplace_back( uniformBuffersMemory[i].mapMemory(0, bufferSize));
        }
    }

    void createBuffer(vk::DeviceSize size, vk::BufferUsageFlags usage, vk::MemoryPropertyFlags properties, vk::raii::Buffer& buffer, vk::raii::DeviceMemory& bufferMemory) {
        vk::BufferCreateInfo bufferInfo{ .size = size, .usage = usage, .sharingMode = vk::SharingMode::eExclusive };
        buffer = vk::raii::Buffer(device, bufferInfo);
        vk::MemoryRequirements memRequirements = buffer.getMemoryRequirements();
        vk::MemoryAllocateInfo allocInfo{ .allocationSize =memRequirements.size, .memoryTypeIndex = findMemoryType(memRequirements.memoryTypeBits, properties) };
        bufferMemory = vk::raii::DeviceMemory(device, allocInfo);
        buffer.bindMemory(bufferMemory, 0);
    }

    void copyBuffer(vk::raii::Buffer & srcBuffer, vk::raii::Buffer & dstBuffer, vk::DeviceSize size) {
        vk::CommandBufferAllocateInfo allocInfo{ .commandPool = commandPool, .level = vk::CommandBufferLevel::ePrimary, .commandBufferCount = 1 };
        vk::raii::CommandBuffer commandCopyBuffer = std::move(device.allocateCommandBuffers(allocInfo).front());
        commandCopyBuffer.begin(vk::CommandBufferBeginInfo { .flags = vk::CommandBufferUsageFlagBits::eOneTimeSubmit });
        commandCopyBuffer.copyBuffer(*srcBuffer, *dstBuffer, vk::BufferCopy(0, 0, size));
        commandCopyBuffer.end();
        queue.submit(vk::SubmitInfo{ .commandBufferCount = 1, .pCommandBuffers = &*commandCopyBuffer }, nullptr);
        queue.waitIdle();
    }

    uint32_t findMemoryType(uint32_t typeFilter, vk::MemoryPropertyFlags properties) {
        vk::PhysicalDeviceMemoryProperties memProperties = physicalDevice.getMemoryProperties();

        for (uint32_t i = 0; i < memProperties.memoryTypeCount; i++) {
            if ((typeFilter & (1 << i)) && (memProperties.memoryTypes[i].propertyFlags & properties) == properties) {
                return i;
            }
        }

        throw std::runtime_error("failed to find suitable memory type!");
    }

    void createCommandBuffers() {
        commandBuffers.clear();
        vk::CommandBufferAllocateInfo allocInfo{ .commandPool = commandPool, .level = vk::CommandBufferLevel::ePrimary,
                                                 .commandBufferCount = MAX_FRAMES_IN_FLIGHT };
        commandBuffers = vk::raii::CommandBuffers( device, allocInfo );
    }

    void recordCommandBuffer(uint32_t imageIndex) {
        commandBuffers[currentFrame].begin( {} );
        // Before starting rendering, transition the swapchain image to COLOR_ATTACHMENT_OPTIMAL
        transition_image_layout(
            imageIndex,
            vk::ImageLayout::eUndefined,
            vk::ImageLayout::eColorAttachmentOptimal,
            {},                                                     // srcAccessMask (no need to wait for previous operations)
            vk::AccessFlagBits2::eColorAttachmentWrite,                // dstAccessMask
            vk::PipelineStageFlagBits2::eTopOfPipe,                   // srcStage
            vk::PipelineStageFlagBits2::eColorAttachmentOutput        // dstStage
        );
        vk::ClearValue clearColor = vk::ClearColorValue(0.0f, 0.0f, 0.0f, 1.0f);
        vk::RenderingAttachmentInfo attachmentInfo = {
            .imageView = swapChainImageViews[imageIndex],
            .imageLayout = vk::ImageLayout::eColorAttachmentOptimal,
            .loadOp = vk::AttachmentLoadOp::eClear,
            .storeOp = vk::AttachmentStoreOp::eStore,
            .clearValue = clearColor
        };
        vk::RenderingInfo renderingInfo = {
            .renderArea = { .offset = { 0, 0 }, .extent = swapChainExtent },
            .layerCount = 1,
            .colorAttachmentCount = 1,
            .pColorAttachments = &attachmentInfo
        };
        commandBuffers[currentFrame].beginRendering(renderingInfo);
        commandBuffers[currentFrame].bindPipeline(vk::PipelineBindPoint::eGraphics, *graphicsPipeline);
        commandBuffers[currentFrame].setViewport(0, vk::Viewport(0.0f, 0.0f, static_cast<float>(swapChainExtent.width), static_cast<float>(swapChainExtent.height), 0.0f, 1.0f));
        commandBuffers[currentFrame].setScissor( 0, vk::Rect2D( vk::Offset2D( 0, 0 ), swapChainExtent ) );
        commandBuffers[currentFrame].bindVertexBuffers(0, *vertexBuffer, {0});
        commandBuffers[currentFrame].bindIndexBuffer( *indexBuffer, 0, vk::IndexTypeValue<decltype(indices)::value_type>::value );
        commandBuffers[currentFrame].drawIndexed(indices.size(), 1, 0, 0, 0);
        commandBuffers[currentFrame].endRendering();
        // After rendering, transition the swapchain image to PRESENT_SRC
        transition_image_layout(
            imageIndex,
            vk::ImageLayout::eColorAttachmentOptimal,
            vk::ImageLayout::ePresentSrcKHR,
            vk::AccessFlagBits2::eColorAttachmentWrite,                 // srcAccessMask
            {},                                                      // dstAccessMask
            vk::PipelineStageFlagBits2::eColorAttachmentOutput,        // srcStage
            vk::PipelineStageFlagBits2::eBottomOfPipe                  // dstStage
        );
        commandBuffers[currentFrame].end();
    }

    void transition_image_layout(
        uint32_t imageIndex,
        vk::ImageLayout old_layout,
        vk::ImageLayout new_layout,
        vk::AccessFlags2 src_access_mask,
        vk::AccessFlags2 dst_access_mask,
        vk::PipelineStageFlags2 src_stage_mask,
        vk::PipelineStageFlags2 dst_stage_mask
        ) {
        vk::ImageMemoryBarrier2 barrier = {
            .srcStageMask = src_stage_mask,
            .srcAccessMask = src_access_mask,
            .dstStageMask = dst_stage_mask,
            .dstAccessMask = dst_access_mask,
            .oldLayout = old_layout,
            .newLayout = new_layout,
            .srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED,
            .dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED,
            .image = swapChainImages[imageIndex],
            .subresourceRange = {
                .aspectMask = vk::ImageAspectFlagBits::eColor,
                .baseMipLevel = 0,
                .levelCount = 1,
                .baseArrayLayer = 0,
                .layerCount = 1
            }
        };
        vk::DependencyInfo dependency_info = {
            .dependencyFlags = {},
            .imageMemoryBarrierCount = 1,
            .pImageMemoryBarriers = &barrier
        };
        commandBuffers[currentFrame].pipelineBarrier2(dependency_info);
    }

    void createSyncObjects() {
        presentCompleteSemaphore.clear();
        renderFinishedSemaphore.clear();
        inFlightFences.clear();

        for (size_t i = 0; i < swapChainImages.size(); i++) {
            presentCompleteSemaphore.emplace_back(device, vk::SemaphoreCreateInfo());
             renderFinishedSemaphore.emplace_back(device, vk::SemaphoreCreateInfo());
        }


        for (size_t i = 0; i < MAX_FRAMES_IN_FLIGHT; i++) {
            inFlightFences.emplace_back(device, vk::FenceCreateInfo { .flags = vk::FenceCreateFlagBits::eSignaled });
        }
    }

    void updateUniformBuffer(uint32_t currentImage) {
        static auto startTime = std::chrono::high_resolution_clock::now();

        auto currentTime = std::chrono::high_resolution_clock::now();
        float time = std::chrono::duration<float>(currentTime - startTime).count();

        UniformBufferObject ubo{};
        ubo.model = rotate(glm::mat4(1.0f), time * glm::radians(90.0f), glm::vec3(0.0f, 0.0f, 1.0f));
        ubo.view = lookAt(glm::vec3(2.0f, 2.0f, 2.0f), glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, 0.0f, 1.0f));
        ubo.proj = glm::perspective(glm::radians(45.0f), static_cast<float>(swapChainExtent.width) / static_cast<float>(swapChainExtent.height), 0.1f, 10.0f);
        ubo.proj[1][1] *= -1;

        memcpy(uniformBuffersMapped[currentImage], &ubo, sizeof(ubo));
    }

    void drawFrame() {
        while ( vk::Result::eTimeout == device.waitForFences( *inFlightFences[currentFrame], vk::True, UINT64_MAX ) )
            ;
        auto [result, imageIndex] = swapChain.acquireNextImage( UINT64_MAX, *presentCompleteSemaphore[semaphoreIndex], nullptr );

        if (result == vk::Result::eErrorOutOfDateKHR) {
            recreateSwapChain();
            return;
        }
        if (result != vk::Result::eSuccess && result != vk::Result::eSuboptimalKHR) {
            throw std::runtime_error("failed to acquire swap chain image!");
        }
        updateUniformBuffer(currentFrame);

        device.resetFences(  *inFlightFences[currentFrame] );
        commandBuffers[currentFrame].reset();
        recordCommandBuffer(imageIndex);

        vk::PipelineStageFlags waitDestinationStageMask( vk::PipelineStageFlagBits::eColorAttachmentOutput );
        const vk::SubmitInfo submitInfo{ .waitSemaphoreCount = 1, .pWaitSemaphores = &*presentCompleteSemaphore[semaphoreIndex],
                            .pWaitDstStageMask = &waitDestinationStageMask, .commandBufferCount = 1, .pCommandBuffers = &*commandBuffers[currentFrame],
                            .signalSemaphoreCount = 1, .pSignalSemaphores = &*renderFinishedSemaphore[imageIndex] };
        queue.submit(submitInfo, *inFlightFences[currentFrame]);


        const vk::PresentInfoKHR presentInfoKHR{ .waitSemaphoreCount = 1, .pWaitSemaphores = &*renderFinishedSemaphore[imageIndex],
                                                .swapchainCount = 1, .pSwapchains = &*swapChain, .pImageIndices = &imageIndex };
        result = queue.presentKHR( presentInfoKHR );
        if (result == vk::Result::eErrorOutOfDateKHR || result == vk::Result::eSuboptimalKHR || framebufferResized) {
            framebufferResized = false;
            recreateSwapChain();
        } else if (result != vk::Result::eSuccess) {
            throw std::runtime_error("failed to present swap chain image!");
        }
        semaphoreIndex = (semaphoreIndex + 1) % presentCompleteSemaphore.size();
        currentFrame = (currentFrame + 1) % MAX_FRAMES_IN_FLIGHT;
    }

    [[nodiscard]] vk::raii::ShaderModule createShaderModule(const std::vector<char>& code) const {
        vk::ShaderModuleCreateInfo createInfo{ .codeSize = code.size(), .pCode = reinterpret_cast<const uint32_t*>(code.data()) };
        vk::raii::ShaderModule shaderModule{ device, createInfo };

        return shaderModule;
    }

    static vk::Format chooseSwapSurfaceFormat(const std::vector<vk::SurfaceFormatKHR>& availableFormats) {
        const auto formatIt = std::ranges::find_if(availableFormats,
        [](const auto& format) {
            return format.format == vk::Format::eB8G8R8A8Srgb &&
                   format.colorSpace == vk::ColorSpaceKHR::eSrgbNonlinear;
        });
        return formatIt != availableFormats.end() ? formatIt->format : availableFormats[0].format;
    }

    static vk::PresentModeKHR chooseSwapPresentMode(const std::vector<vk::PresentModeKHR>& availablePresentModes) {
        return std::ranges::any_of(availablePresentModes,
            [](const vk::PresentModeKHR value) { return vk::PresentModeKHR::eMailbox == value; } ) ? vk::PresentModeKHR::eMailbox : vk::PresentModeKHR::eFifo;
    }

    vk::Extent2D chooseSwapExtent(const vk::SurfaceCapabilitiesKHR& capabilities) {
        if (capabilities.currentExtent.width != std::numeric_limits<uint32_t>::max()) {
            return capabilities.currentExtent;
        }
        int width, height;
        glfwGetFramebufferSize(window, &width, &height);

        return {
            std::clamp<uint32_t>(width, capabilities.minImageExtent.width, capabilities.maxImageExtent.width),
            std::clamp<uint32_t>(height, capabilities.minImageExtent.height, capabilities.maxImageExtent.height)
        };
    }

    std::vector<const char*> getRequiredExtensions() {
        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;
    }

    static std::vector<char> readFile(const std::string& filename) {
        std::ifstream file(filename, std::ios::ate | std::ios::binary);
        if (!file.is_open()) {
            throw std::runtime_error("failed to open file!");
        }
        std::vector<char> buffer(file.tellg());
        file.seekg(0, std::ios::beg);
        file.read(buffer.data(), static_cast<std::streamsize>(buffer.size()));
        file.close();
        return buffer;
    }
};

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

    return EXIT_SUCCESS;
}