#include <VulkanTutorial.h>

#include <utils.h>
#include <Logger.h>

#include <SDL2/SDL_vulkan.h>

#include <Eigen/Geometry>

#include <cassert>
#include <stdexcept>
#include <array>
#include <vector>
#include <algorithm>
#include <cstring>


VkVertexInputBindingDescription Vertex::binding_description() {
    return {
        .binding = 0,
        .stride = sizeof(Vertex),
        .inputRate = VK_VERTEX_INPUT_RATE_VERTEX,
    };
}

std::array<VkVertexInputAttributeDescription, 2> Vertex::attributes_description() {
    return {
        VkVertexInputAttributeDescription {
            .location = 0,
            .binding = 0,
            .format = VK_FORMAT_R32G32B32_SFLOAT,
            .offset = offsetof(Vertex, position),
        },
        {
            .location = 1,
            .binding = 0,
            .format = VK_FORMAT_R32G32B32_SFLOAT,
            .offset = offsetof(Vertex, color),
        },
    };
}


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

    {{-0.5f, -0.5f, 0.5f}, {0.0f, 1.0f, 1.0f}},
    {{0.5f, -0.5f, 0.5f}, {1.0f, 0.0f, 1.0f}},
    {{-0.5f, 0.5f, 0.5f}, {1.0f, 1.0f, 0.0f}},
    {{0.5f, 0.5f, 0.5f}, {0.2f, 0.2f, 0.2f}},
};

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

    1, 5, 3,
    3, 5, 7,

    5, 4, 7,
    7, 4, 6,

    4, 0, 6,
    6, 0, 2,

    0, 4, 1,
    1, 4, 5,

    2, 3, 6,
    6, 3, 7,
};

struct Uniforms {
    alignas(16) Eigen::Matrix4f scene_from_model;
    alignas(16) Eigen::Matrix4f projection_from_scene;
};


VulkanTutorial::VulkanTutorial() {
    m_swapchain.register_creation_callback(
        std::bind(&VulkanTutorial::create_swapchain_objects, this, std::placeholders::_1));
    m_swapchain.register_destruction_callback(
        std::bind(&VulkanTutorial::destroy_swapchain_objects, this));
}

VulkanTutorial::~VulkanTutorial() {
    shutdown();
}

void VulkanTutorial::initialize(SDL_Window* window) {
    auto const context_settings = Vulkan::ContextSettings()
#if defined(VKEXPE_ENABLE_VALIDATION) || !defined(NDEBUG)
        .with_debug(true)
#endif
        .with_queue(GRAPHIC_QUEUE, VK_QUEUE_GRAPHICS_BIT)
        .with_window(window);
    m_context.initialize(context_settings);

    create_command_pool();
    create_descriptor_set_layout();
    create_vertex_buffer();
    create_index_buffer();

    auto const swapchain_settings = Vulkan::SwapchainSettings(&m_context)
        .with_queue(m_context.queue_family(GRAPHIC_QUEUE));
    m_swapchain.initialize(swapchain_settings);
}

void VulkanTutorial::shutdown() {
    if(!m_context.instance())
        return;

    vkDeviceWaitIdle(m_context.device());

    destroy_swapchain_objects();

    m_context.free_memory(m_vertex_buffer_memory);
    m_context.destroy_command_pool(m_command_pool);
    m_context.free_memory(m_index_buffer_memory);
    m_context.destroy_buffer(m_index_buffer);
    m_context.free_memory(m_vertex_buffer_memory);
    m_context.destroy_buffer(m_vertex_buffer);
    m_context.destroy_descriptor_set_layout(m_descriptor_set_layout);

    for(VkSemaphore semaphore: m_render_done)
        m_context.destroy_semaphore(semaphore);
    m_render_done.clear();

    m_swapchain.shutdown();
    m_context.shutdown();
}

void VulkanTutorial::draw_frame() {
    m_swapchain.begin_frame();
    auto const image_index = m_swapchain.current_image_index();

    const auto now = Clock::now();
    if(m_last_frame_time.time_since_epoch() != Duration(0)) {
        m_time += now - m_last_frame_time;
    }
    m_last_frame_time = now;

    const float alpha = SecondsD(m_time).count() * (2.0 * M_PI) / 3.0;
    const float dist = 2.0f;
    const Eigen::Matrix4f view = look_at_matrix(
        // Eigen::Vector3f(0.0f, 0.0f, -dist),
        Eigen::Vector3f(0.0f, -dist, -dist),
        // dist * Eigen::Vector3f(std::cos(alpha), std::sin(alpha), -1.0),
        Eigen::Vector3f::Zero(),
        -Eigen::Vector3f::UnitY()
    );

    const float fov = M_PI / 3.0f;
    const float near = 0.1f;
    const float far = 10.0f;
    const float hx = near * std::tan(fov / 2.0f);
    const float hy = hx * m_swapchain.extent().height / m_swapchain.extent().width;
    const Eigen::Matrix4f proj = projection_matrix(
        -hx, hx,
        -hy, hy,
        near, far
    );

    using Transform = Eigen::Transform<float, 3, Eigen::Affine>;
    Transform model = Transform::Identity();
    model.rotate(Eigen::AngleAxisf(
        alpha,
        Eigen::Vector3f::UnitY()
    ));

    const Uniforms uniforms = {
        .scene_from_model = model.matrix(),
        .projection_from_scene = proj * view,
    };

    void* uniform_buffer;
    vkMapMemory(
        m_context.device(),
        m_uniform_buffer_memory,
        m_uniform_buffer_offsets[image_index],
        sizeof(Uniforms),
        0,
        &uniform_buffer
    );
    std::memcpy(uniform_buffer, &uniforms, sizeof(Uniforms));
    vkUnmapMemory(m_context.device(), m_uniform_buffer_memory);

    VkSemaphore wait_semaphores[] = {
        m_swapchain.ready_to_render(),
    };
    VkPipelineStageFlags stages[] = {
        VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT,
    };
    VkSubmitInfo submit_info {
        .sType = VK_STRUCTURE_TYPE_SUBMIT_INFO,
        .waitSemaphoreCount = 1,
        .pWaitSemaphores = wait_semaphores,
        .pWaitDstStageMask = stages,
        .commandBufferCount = 1,
        .pCommandBuffers = &m_command_buffers[image_index],
        .signalSemaphoreCount = 1,
        .pSignalSemaphores = &m_render_done[image_index],
    };

    if(vkQueueSubmit(
        m_context.queue(GRAPHIC_QUEUE),
        1, &submit_info,
        m_swapchain.render_done()
    ))
        throw std::runtime_error("failed to submit draw command buffer");

    m_swapchain.swap_buffers({1, &m_render_done[image_index]});
}

void VulkanTutorial::invalidate_swapchain() {
    m_swapchain.invalidate();
}

void VulkanTutorial::create_swapchain_objects(uint32_t image_count) {
    create_render_pass();
    create_framebuffers();
    create_uniform_buffer();
    create_descriptor_pool();
    create_descriptor_sets();
    create_graphic_pipeline();
    create_command_buffers();

    m_render_done.resize(m_swapchain.image_count());

    VkSemaphoreCreateInfo semaphore_info {
        .sType = VK_STRUCTURE_TYPE_SEMAPHORE_CREATE_INFO,
    };

    for(size_t index = 0; index < m_render_done.size(); index += 1) {
        if(vkCreateSemaphore(
            m_context.device(),
            &semaphore_info,
            nullptr,
            &m_render_done[index]
        ) != VK_SUCCESS)
            throw std::runtime_error("failed to create semaphore");
    }
}

void VulkanTutorial::destroy_swapchain_objects() {
    if(m_command_pool == VK_NULL_HANDLE)
        return;

    vkFreeCommandBuffers(
        m_context.device(),
        m_command_pool,
        uint32_t(m_command_buffers.size()),
        m_command_buffers.data()
    );
    m_command_buffers.clear();

    for(VkBuffer buffer: m_uniform_buffers)
        m_context.destroy_buffer(buffer);
    m_uniform_buffers.clear();
    m_context.free_memory(m_uniform_buffer_memory);

    m_context.destroy_descriptor_pool(m_descriptor_pool);

    for(VkFramebuffer framebuffer: m_framebuffers)
        m_context.destroy_framebuffer(framebuffer);
    m_framebuffers.clear();

    m_context.destroy_pipeline(m_pipeline);
    m_context.destroy_pipeline_layout(m_pipeline_layout);
    m_context.destroy_render_pass(m_render_pass);
}

void VulkanTutorial::create_render_pass() {
    VkAttachmentDescription color_attachment {
        .format = m_context.surface_format().format,
        .samples = VK_SAMPLE_COUNT_1_BIT,
        .loadOp = VK_ATTACHMENT_LOAD_OP_CLEAR,
        .storeOp = VK_ATTACHMENT_STORE_OP_STORE,
        .stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE,
        .stencilStoreOp = VK_ATTACHMENT_STORE_OP_DONT_CARE,
        .initialLayout = VK_IMAGE_LAYOUT_UNDEFINED,
        .finalLayout = VK_IMAGE_LAYOUT_PRESENT_SRC_KHR,
    };

    VkAttachmentReference color_attachment_ref = {
        .attachment = 0,
        .layout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL,
    };

    VkSubpassDescription subpass {
        .pipelineBindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS,
        .colorAttachmentCount = 1,
        .pColorAttachments = &color_attachment_ref,
    };

    VkSubpassDependency subpass_dep = {
        .srcSubpass = VK_SUBPASS_EXTERNAL,
        .dstSubpass = 0,
        .srcStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT,
        .dstStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT,
        .srcAccessMask = 0,
        .dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT,
    };

    VkRenderPassCreateInfo render_pass_info {
        .sType = VK_STRUCTURE_TYPE_RENDER_PASS_CREATE_INFO,
        .attachmentCount = 1,
        .pAttachments = &color_attachment,
        .subpassCount = 1,
        .pSubpasses = &subpass,
        .dependencyCount = 1,
        .pDependencies = &subpass_dep,
    };

    if(vkCreateRenderPass(
        m_context.device(),
        &render_pass_info,
        nullptr,
        &m_render_pass
    ) != VK_SUCCESS)
        throw std::runtime_error("failed to create render pass");
}

void VulkanTutorial::create_descriptor_set_layout() {
    VkDescriptorSetLayoutBinding binding {
        .binding = 0,
        .descriptorType = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER,
        .descriptorCount = 1,
        .stageFlags = VK_SHADER_STAGE_VERTEX_BIT,
    };

    VkDescriptorSetLayoutCreateInfo layout_info {
        .sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_LAYOUT_CREATE_INFO,
        .bindingCount = 1,
        .pBindings = &binding,
    };
    if(vkCreateDescriptorSetLayout(
        m_context.device(),
        &layout_info,
        nullptr,
        &m_descriptor_set_layout
    ) != VK_SUCCESS)
        throw std::runtime_error("failed to create descriptor set layout");
}

void VulkanTutorial::create_graphic_pipeline() {
    auto const vertex_shader_module =
        m_context.create_shader_module_from_file("shaders/shader.vert.spv");
    auto const vertex_shader_guard = make_guard([&]{
        vkDestroyShaderModule(m_context.device(), vertex_shader_module, nullptr);
    });

    auto const fragment_shader_module =
        m_context.create_shader_module_from_file("shaders/shader.frag.spv");
    auto const fragment_shader_guard = make_guard([&]{
        vkDestroyShaderModule(m_context.device(), fragment_shader_module, nullptr);
    });

    VkPipelineShaderStageCreateInfo shader_stage_infos[] = {
        {
            .sType = VK_STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_CREATE_INFO,
            .stage = VK_SHADER_STAGE_VERTEX_BIT,
            .module = vertex_shader_module,
            .pName = "main",
        },
        {
            .sType = VK_STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_CREATE_INFO,
            .stage = VK_SHADER_STAGE_FRAGMENT_BIT,
            .module = fragment_shader_module,
            .pName = "main",
        },
    };

    const VkVertexInputBindingDescription vertex_bindings[] = {
        Vertex::binding_description(),
    };
    const auto vertex_attributes = Vertex::attributes_description();

    VkPipelineVertexInputStateCreateInfo vertex_info {
        .sType = VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO,
        .vertexBindingDescriptionCount = 1,
        .pVertexBindingDescriptions = vertex_bindings,
        .vertexAttributeDescriptionCount = uint32_t(vertex_attributes.size()),
        .pVertexAttributeDescriptions = vertex_attributes.data(),
    };

    VkPipelineInputAssemblyStateCreateInfo assembly_info {
        .sType = VK_STRUCTURE_TYPE_PIPELINE_INPUT_ASSEMBLY_STATE_CREATE_INFO,
        .topology = VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST,
        .primitiveRestartEnable = VK_FALSE,
    };

    VkViewport viewport {
        .x = 0.0f,
        .y = 0.0f,
        .width = float(m_swapchain.extent().width),
        .height = float(m_swapchain.extent().height),
        .minDepth = 0.0f,
        .maxDepth = 1.0f,
    };

    VkRect2D scissor = {
        .offset = { 0, 0 },
        .extent = m_swapchain.extent(),
    };

    VkPipelineViewportStateCreateInfo viewport_info {
        .sType = VK_STRUCTURE_TYPE_PIPELINE_VIEWPORT_STATE_CREATE_INFO,
        .viewportCount = 1,
        .pViewports = &viewport,
        .scissorCount = 1,
        .pScissors = &scissor,
    };

    VkPipelineRasterizationStateCreateInfo rasterization_info {
        .sType = VK_STRUCTURE_TYPE_PIPELINE_RASTERIZATION_STATE_CREATE_INFO,
        .depthClampEnable = VK_FALSE,
        .rasterizerDiscardEnable = VK_FALSE,
        .polygonMode = VK_POLYGON_MODE_FILL,
        .cullMode = VK_CULL_MODE_BACK_BIT,
        .frontFace = VK_FRONT_FACE_CLOCKWISE,
        .depthBiasEnable = VK_FALSE,
        .depthBiasConstantFactor = 0.0f,
        .depthBiasClamp = 0.0f,
        .depthBiasSlopeFactor = 0.0f,
        .lineWidth = 1.0f,
    };

    VkPipelineMultisampleStateCreateInfo multisample_info {
        .sType = VK_STRUCTURE_TYPE_PIPELINE_MULTISAMPLE_STATE_CREATE_INFO,
        .rasterizationSamples = VK_SAMPLE_COUNT_1_BIT,
        .sampleShadingEnable = VK_FALSE,
        .minSampleShading = 1.0f,
        .pSampleMask = nullptr,
        .alphaToCoverageEnable = VK_FALSE,
        .alphaToOneEnable = VK_FALSE,
    };

    VkPipelineColorBlendAttachmentState color_blend_attachment {
        .blendEnable = VK_FALSE,
        .srcColorBlendFactor = VK_BLEND_FACTOR_ONE,
        .dstColorBlendFactor = VK_BLEND_FACTOR_ZERO,
        .colorBlendOp = VK_BLEND_OP_ADD,
        .srcAlphaBlendFactor = VK_BLEND_FACTOR_ONE,
        .dstAlphaBlendFactor = VK_BLEND_FACTOR_ZERO,
        .alphaBlendOp = VK_BLEND_OP_ADD,
        .colorWriteMask =
            VK_COLOR_COMPONENT_R_BIT |
            VK_COLOR_COMPONENT_G_BIT |
            VK_COLOR_COMPONENT_B_BIT |
            VK_COLOR_COMPONENT_A_BIT,
    };

    VkPipelineColorBlendStateCreateInfo color_blend_info {
        .sType = VK_STRUCTURE_TYPE_PIPELINE_COLOR_BLEND_STATE_CREATE_INFO,
        .logicOpEnable = VK_FALSE,
        .logicOp = VK_LOGIC_OP_COPY,
        .attachmentCount = 1,
        .pAttachments = &color_blend_attachment,
        .blendConstants = { 0.0f, 0.0f, 0.0f, 0.0f },
    };

    VkPipelineLayoutCreateInfo layout_info = {
        .sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO,
        .setLayoutCount = 1,
        .pSetLayouts = &m_descriptor_set_layout,
        .pushConstantRangeCount = 0,
        .pPushConstantRanges = nullptr,
    };

    if(vkCreatePipelineLayout(
        m_context.device(),
        &layout_info,
        nullptr,
        &m_pipeline_layout
    ) != VK_SUCCESS)
        throw std::runtime_error("failed to create pipeline layout");

    VkGraphicsPipelineCreateInfo pipeline_info {
        .sType = VK_STRUCTURE_TYPE_GRAPHICS_PIPELINE_CREATE_INFO,
        .stageCount = 2,
        .pStages = shader_stage_infos,
        .pVertexInputState = &vertex_info,
        .pInputAssemblyState = &assembly_info,
        .pViewportState = &viewport_info,
        .pRasterizationState = &rasterization_info,
        .pMultisampleState = &multisample_info,
        .pDepthStencilState = nullptr,
        .pColorBlendState = &color_blend_info,
        .pDynamicState = nullptr,
        .layout = m_pipeline_layout,
        .renderPass = m_render_pass,
        .subpass = 0,
        .basePipelineHandle = VK_NULL_HANDLE,
        .basePipelineIndex = -1,
    };

    if(vkCreateGraphicsPipelines(
        m_context.device(),
        VK_NULL_HANDLE,
        1, &pipeline_info,
        nullptr,
        &m_pipeline
    ) != VK_SUCCESS)
        throw std::runtime_error("failed to create graphic pipeline");
}

void VulkanTutorial::create_framebuffers() {
    m_framebuffers.resize(m_swapchain.image_count());

    for(size_t index = 0; index < m_framebuffers.size(); index += 1) {
        VkImageView view = m_swapchain.image_view(index);

        VkFramebufferCreateInfo framebuffer_info {
            .sType = VK_STRUCTURE_TYPE_FRAMEBUFFER_CREATE_INFO,
            .renderPass = m_render_pass,
            .attachmentCount = 1,
            .pAttachments = &view,
            .width = m_swapchain.extent().width,
            .height = m_swapchain.extent().height,
            .layers = 1,
        };

        if(vkCreateFramebuffer(
            m_context.device(),
            &framebuffer_info,
            nullptr,
            &m_framebuffers[index]
        ) != VK_SUCCESS)
            throw std::runtime_error("failed to create framebuffer");
    }
}

void VulkanTutorial::create_command_pool() {
    if(m_command_pool != VK_NULL_HANDLE)
        return;

    VkCommandPoolCreateInfo pool_info {
        .sType = VK_STRUCTURE_TYPE_COMMAND_POOL_CREATE_INFO,
        .flags = 0,
        .queueFamilyIndex = m_context.queue_family(GRAPHIC_QUEUE),
    };

    if(vkCreateCommandPool(
        m_context.device(),
        &pool_info,
        nullptr,
        &m_command_pool
    ) != VK_SUCCESS)
        throw std::runtime_error("failed to create command pool");
}

void VulkanTutorial::create_vertex_buffer() {
    if(m_vertex_buffer != VK_NULL_HANDLE)
        return;

    VkDeviceSize size = sizeof(vertices[0]) * vertices.size();
    std::tie(m_vertex_buffer, m_vertex_buffer_memory) = m_context.create_buffer(
        size, (char*)vertices.data(),
        VK_BUFFER_USAGE_VERTEX_BUFFER_BIT,
        VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT,
        m_context.queue_family(GRAPHIC_QUEUE)
    );
}

void VulkanTutorial::create_index_buffer() {
    if(m_index_buffer != VK_NULL_HANDLE)
        return;

    VkDeviceSize size = sizeof(indices[0]) * indices.size();
    std::tie(m_index_buffer, m_index_buffer_memory) = m_context.create_buffer(
        size, (char*)indices.data(),
        VK_BUFFER_USAGE_INDEX_BUFFER_BIT,
        VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT,
        m_context.queue_family(GRAPHIC_QUEUE)
    );
}

void VulkanTutorial::create_uniform_buffer() {
    m_uniform_buffers.assign(m_swapchain.image_count(), VK_NULL_HANDLE);
    for(size_t index = 0; index < m_uniform_buffers.size(); index += 1) {
        VkBufferCreateInfo buffer_info {
            .sType = VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO,
            .size = sizeof(Uniforms),
            .usage = VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT,
            .sharingMode = VK_SHARING_MODE_EXCLUSIVE,
        };

        if(vkCreateBuffer(
            m_context.device(),
            &buffer_info,
            nullptr,
            &m_uniform_buffers[index]
        ) != VK_SUCCESS)
            throw std::runtime_error("failed to create buffer");
    }

    VkMemoryRequirements memory_requirements;
    vkGetBufferMemoryRequirements(
        m_context.device(),
        m_uniform_buffers[0],
        &memory_requirements
    );

    m_uniform_buffer_memory = m_context.allocate_memory(
        memory_requirements.size * m_swapchain.image_count(),
        memory_requirements.memoryTypeBits,
        VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT
        | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT
    );

    m_uniform_buffer_offsets.resize(m_uniform_buffers.size());
    for(size_t index = 0; index < m_uniform_buffers.size(); index += 1) {
        m_uniform_buffer_offsets[index] = index * memory_requirements.size;
        vkBindBufferMemory(
            m_context.device(),
            m_uniform_buffers[index],
            m_uniform_buffer_memory,
            m_uniform_buffer_offsets[index]
        );
    }
}

void VulkanTutorial::create_descriptor_pool() {
    VkDescriptorPoolSize pool_size {
        .type = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER,
        .descriptorCount = uint32_t(m_swapchain.image_count()),
    };

    VkDescriptorPoolCreateInfo pool_info {
        .sType = VK_STRUCTURE_TYPE_DESCRIPTOR_POOL_CREATE_INFO,
        .maxSets = uint32_t(m_swapchain.image_count()),
        .poolSizeCount = 1,
        .pPoolSizes = &pool_size,
    };
    if(vkCreateDescriptorPool(
        m_context.device(),
        &pool_info,
        nullptr,
        &m_descriptor_pool
    ) != VK_SUCCESS)
        throw std::runtime_error("failed to create descriptor pool");
}

void VulkanTutorial::create_descriptor_sets() {
    const std::vector<VkDescriptorSetLayout> layouts(
        m_swapchain.image_count(), m_descriptor_set_layout);

    VkDescriptorSetAllocateInfo alloc_info {
        .sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_ALLOCATE_INFO,
        .descriptorPool = m_descriptor_pool,
        .descriptorSetCount = uint32_t(layouts.size()),
        .pSetLayouts = layouts.data(),
    };

    m_descriptor_sets.resize(m_swapchain.image_count());
    if(vkAllocateDescriptorSets(
        m_context.device(),
        &alloc_info,
        m_descriptor_sets.data()
    ) != VK_SUCCESS)
        throw std::runtime_error("failed to allocate descriptor sets");

    for(size_t index = 0; index < m_swapchain.image_count(); index += 1) {
        VkDescriptorBufferInfo buffer_info {
            .buffer = m_uniform_buffers[index],
            .offset = 0,
            .range = sizeof(Uniforms),
        };

        VkWriteDescriptorSet write {
            .sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,
            .dstSet = m_descriptor_sets[index],
            .dstBinding = 0,
            .dstArrayElement = 0,
            .descriptorCount = 1,
            .descriptorType = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER,
            .pBufferInfo = &buffer_info,
        };
        vkUpdateDescriptorSets(
            m_context.device(),
            1, &write,
            0, nullptr
        );
    }
}

void VulkanTutorial::create_command_buffers() {
    m_command_buffers.resize(m_framebuffers.size());

    VkCommandBufferAllocateInfo allocate_info {
        .sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_ALLOCATE_INFO,
        .commandPool = m_command_pool,
        .level = VK_COMMAND_BUFFER_LEVEL_PRIMARY,
        .commandBufferCount = uint32_t(m_command_buffers.size()),
    };

    if(vkAllocateCommandBuffers(
        m_context.device(),
        &allocate_info,
        m_command_buffers.data()
    ) != VK_SUCCESS)
        throw std::runtime_error("failed to allocate command buffers");

    for(size_t index = 0; index < m_command_buffers.size(); index += 1) {
        VkCommandBuffer command_buffer = m_command_buffers[index];

        VkCommandBufferBeginInfo begin_info {
            .sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO,
            .flags = 0,
            .pInheritanceInfo = nullptr,
        };

        logger.debug() << "record command buffer " << index << " (" << command_buffer << ")";

        if(vkBeginCommandBuffer(
            command_buffer,
            &begin_info
        ) != VK_SUCCESS)
            throw std::runtime_error("failed to begin command buffer");

        VkClearValue clear_color = {
            .color = {
                .float32 = { 0.0f, 0.0f, 0.0f, 1.0f }
            }
        };

        VkRenderPassBeginInfo pass_info {
            .sType = VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO,
            .renderPass = m_render_pass,
            .framebuffer = m_framebuffers[index],
            .renderArea = {
                .offset = { 0, 0 },
                .extent = m_swapchain.extent(),
            },
            .clearValueCount = 1,
            .pClearValues = &clear_color,
        };

        vkCmdBeginRenderPass(
            command_buffer,
            &pass_info,
            VK_SUBPASS_CONTENTS_INLINE
        );

        vkCmdBindPipeline(
            command_buffer,
            VK_PIPELINE_BIND_POINT_GRAPHICS,
            m_pipeline
        );

        VkBuffer vertex_buffers[] = {
            m_vertex_buffer,
        };
        VkDeviceSize offsets[] = {
            0,
        };
        vkCmdBindVertexBuffers(
            command_buffer,
            0,
            1,
            vertex_buffers,
            offsets
        );

        vkCmdBindDescriptorSets(
            command_buffer,
            VK_PIPELINE_BIND_POINT_GRAPHICS,
            m_pipeline_layout,
            0, 1, &m_descriptor_sets[index],
            0, nullptr
        );

        vkCmdBindIndexBuffer(
            command_buffer,
            m_index_buffer,
            0,
            VK_INDEX_TYPE_UINT16
        );

        vkCmdDrawIndexed(
            command_buffer,
            uint32_t(indices.size()),
            1,
            0,
            0,
            0
        );

        vkCmdEndRenderPass(command_buffer);

        if(vkEndCommandBuffer(command_buffer) != VK_SUCCESS)
            throw("failed to record command buffer");
    }
}