use super::*;
use crate::VALIDATION_ENABLED;

use ::anyhow::{anyhow, Result};
use ::log::*;
use ::std::collections::HashSet;
use ::std::ffi::CStr;
use ::std::os::raw::c_void;
use ::vulkanalia::prelude::v1_0::*;
use ::vulkanalia::window as vk_window;
use ::winit::window::Window;

extern "system" fn debug_callback(
    severity: vk::DebugUtilsMessageSeverityFlagsEXT,
    type_: vk::DebugUtilsMessageTypeFlagsEXT,
    data: *const vk::DebugUtilsMessengerCallbackDataEXT,
    _: *mut c_void,
) -> vk::Bool32 {
    let data = unsafe { *data };
    let message = unsafe { CStr::from_ptr(data.message) }.to_string_lossy();

    if severity >= vk::DebugUtilsMessageSeverityFlagsEXT::ERROR {
        error!("({:?}) {}", type_, message);
    } else if severity >= vk::DebugUtilsMessageSeverityFlagsEXT::WARNING {
        warn!("({:?}) {}", type_, message);
    } else if severity >= vk::DebugUtilsMessageSeverityFlagsEXT::INFO {
        debug!("({:?}) {}", type_, message);
    } else {
        trace!("({:?}) {}", type_, message);
    }

    vk::FALSE
}

pub(super) unsafe fn create_instance(
    window: &Window,
    entry: &Entry,
    data: &mut AppData,
) -> Result<Instance> {
    // Application Info
    let application_info = vk::ApplicationInfo::builder()
        .application_name(b"Vulkan Tutorial\0")
        .application_version(vk::make_version(1, 0, 0))
        .engine_name(b"No Engine\0")
        .engine_version(vk::make_version(1, 0, 0))
        .api_version(vk::make_version(1, 0, 0));

    // Layers
    let available_layers = entry
        .enumerate_instance_layer_properties()?
        .iter()
        .map(|l| l.layer_name)
        .collect::<HashSet<_>>();

    if VALIDATION_ENABLED && !available_layers.contains(&VALIDATION_LAYER) {
        return Err(anyhow!("Validation layer requested but not supported."));
    }

    let layers = if VALIDATION_ENABLED {
        vec![VALIDATION_LAYER.as_ptr()]
    } else {
        Vec::new()
    };

    // Extensions
    let mut extensions = vk_window::get_required_instance_extensions(window)
        .iter()
        .map(|e| e.as_ptr())
        .collect::<Vec<_>>();
    if VALIDATION_ENABLED {
        extensions.push(vk::EXT_DEBUG_UTILS_EXTENSION.name.as_ptr());
    }

    // Compatibility extension for macOS
    let flags = if entry
        .enumerate_instance_extension_properties(None)?
        .iter()
        .any(|e| e.extension_name == vk::KHR_PORTABILITY_ENUMERATION_EXTENSION.name)
    {
        extensions.push(vk::KHR_PORTABILITY_ENUMERATION_EXTENSION.name.as_ptr());
        extensions.push(
            vk::KHR_GET_PHYSICAL_DEVICE_PROPERTIES2_EXTENSION
                .name
                .as_ptr(),
        );
        vk::InstanceCreateFlags::ENUMERATE_PORTABILITY_KHR
    } else {
        vk::InstanceCreateFlags::empty()
    };

    // Create
    let mut info = vk::InstanceCreateInfo::builder()
        .application_info(&application_info)
        .enabled_layer_names(&layers)
        .enabled_extension_names(&extensions)
        .flags(flags);

    let mut debug_info = vk::DebugUtilsMessengerCreateInfoEXT::builder()
        .message_severity(vk::DebugUtilsMessageSeverityFlagsEXT::all())
        .message_type(vk::DebugUtilsMessageTypeFlagsEXT::all())
        .user_callback(Some(debug_callback));

    if VALIDATION_ENABLED {
        info = info.push_next(&mut debug_info);
    }

    let instance = entry.create_instance(&info, None)?;

    // Messenger
    if VALIDATION_ENABLED {
        data.messenger = instance.create_debug_utils_messenger_ext(&debug_info, None)?;
    }

    Ok(instance)
}

pub(super) unsafe fn pick_physical_device(instance: &Instance, data: &mut AppData) -> Result<()> {
    for physical_device in instance.enumerate_physical_devices()? {
        let properties = instance.get_physical_device_properties(physical_device);

        if let Err(error) = check_physical_device(instance, data, physical_device) {
            warn!(
                "Skipping physical device (`{}`): {}",
                properties.device_name, error
            );
        } else {
            info!("Selected physical device (`{}`).", properties.device_name);
            data.physical_device = physical_device;
            return Ok(());
        }
    }

    Err(anyhow!("Failed to find suitable physical device."))
}

pub(super) unsafe fn check_physical_device(
    instance: &Instance,
    data: &AppData,
    physical_device: vk::PhysicalDevice,
) -> Result<()> {
    QueueFamilyIndicies::get(instance, data, physical_device)?;
    check_physical_device_extensions(instance, physical_device)?;

    let support = SwapchainSupport::get(instance, data, physical_device)?;
    if support.formats.is_empty() || support.present_modes.is_empty() {
        return Err(anyhow!(SuitabilityError("Insufficient swapchain support.")));
    }

    Ok(())
}

pub(super) unsafe fn check_physical_device_extensions(
    instance: &Instance,
    physical_device: vk::PhysicalDevice,
) -> Result<()> {
    let extensions = instance
        .enumerate_device_extension_properties(physical_device, None)?
        .iter()
        .map(|e| e.extension_name)
        .collect::<HashSet<_>>();

    if DEVICE_EXTENSIONS.iter().all(|e| extensions.contains(e)) {
        Ok(())
    } else {
        Err(anyhow!(SuitabilityError(
            "Missing required device extensions."
        )))
    }
}

pub(super) unsafe fn create_logical_device(
    instance: &Instance,
    data: &mut AppData,
) -> Result<Device> {
    // Queue Create Infos
    let indices = QueueFamilyIndicies::get(instance, data, data.physical_device)?;

    let mut unique_indices = HashSet::new();
    unique_indices.insert(indices.graphics);
    unique_indices.insert(indices.present);

    let queue_priorities = &[1.0];
    let queue_infos = unique_indices
        .iter()
        .map(|i| {
            vk::DeviceQueueCreateInfo::builder()
                .queue_family_index(*i)
                .queue_priorities(queue_priorities)
        })
        .collect::<Vec<_>>();

    // Layers
    let layers = if VALIDATION_ENABLED {
        vec![VALIDATION_LAYER.as_ptr()]
    } else {
        vec![]
    };

    // Extensions
    let mut extensions = DEVICE_EXTENSIONS
        .iter()
        .map(|n| n.as_ptr())
        .collect::<Vec<_>>();

    // mac OS Metal -> Vulkan rendering fix
    if instance
        .enumerate_device_extension_properties(data.physical_device, None)?
        .iter()
        .any(|e| e.extension_name == vk::KHR_PORTABILITY_SUBSET_EXTENSION.name)
    {
        extensions.push(vk::KHR_PORTABILITY_SUBSET_EXTENSION.name.as_ptr());
    }

    // Features
    let features = vk::PhysicalDeviceFeatures::builder();

    // Create
    let info = vk::DeviceCreateInfo::builder()
        .queue_create_infos(&queue_infos)
        .enabled_layer_names(&layers)
        .enabled_extension_names(&extensions)
        .enabled_features(&features);

    let device = instance.create_device(data.physical_device, &info, None)?;

    // Queues
    data.graphics_queue = device.get_device_queue(indices.graphics, 0);
    data.present_queue = device.get_device_queue(indices.present, 0);

    Ok(device)
}

pub(super) fn get_swapchain_surface_format(
    formats: &[vk::SurfaceFormatKHR],
) -> vk::SurfaceFormatKHR {
    formats
        .iter()
        .cloned()
        .find(|f| {
            f.format == vk::Format::B8G8R8A8_SRGB
                && f.color_space == vk::ColorSpaceKHR::SRGB_NONLINEAR
        })
        .unwrap_or_else(|| formats[0])
}

pub(super) fn get_swapchain_present_mode(
    present_modes: &[vk::PresentModeKHR],
) -> vk::PresentModeKHR {
    present_modes
        .iter()
        .cloned()
        .find(|m| *m == vk::PresentModeKHR::MAILBOX)
        .unwrap_or(vk::PresentModeKHR::FIFO)
}

pub(super) fn get_swapchain_extent(
    window: &Window,
    capabilities: vk::SurfaceCapabilitiesKHR,
) -> vk::Extent2D {
    if capabilities.current_extent.width != u32::MAX {
        capabilities.current_extent
    } else {
        let size = window.inner_size();
        let clamp = |min: u32, max: u32, v: u32| min.max(max.min(v));
        vk::Extent2D::builder()
            .width(clamp(
                capabilities.min_image_extent.width,
                capabilities.max_image_extent.width,
                size.width,
            ))
            .height(clamp(
                capabilities.min_image_extent.height,
                capabilities.max_image_extent.height,
                size.height,
            ))
            .build()
    }
}

pub(super) unsafe fn create_swapchain(
    window: &Window,
    instance: &Instance,
    device: &Device,
    data: &mut AppData,
) -> Result<()> {
    let indices = QueueFamilyIndicies::get(instance, data, data.physical_device)?;
    let support = SwapchainSupport::get(instance, data, data.physical_device)?;

    let surface_format = get_swapchain_surface_format(&support.formats);
    let present_mode = get_swapchain_present_mode(&support.present_modes);
    let extent = get_swapchain_extent(window, support.capabilities);

    let mut image_count = support.capabilities.min_image_count + 1;
    if support.capabilities.max_image_count != 0
        && image_count > support.capabilities.max_image_count
    {
        image_count = support.capabilities.max_image_count;
    }

    let mut queue_family_indices = vec![];
    let image_sharing_mode = if indices.graphics != indices.present {
        queue_family_indices.push(indices.graphics);
        queue_family_indices.push(indices.present);
        vk::SharingMode::CONCURRENT
    } else {
        vk::SharingMode::EXCLUSIVE
    };

    let info = vk::SwapchainCreateInfoKHR::builder()
        .surface(data.surface)
        .min_image_count(image_count)
        .image_format(surface_format.format)
        .image_color_space(surface_format.color_space)
        .image_extent(extent)
        .image_array_layers(1)
        .image_usage(vk::ImageUsageFlags::COLOR_ATTACHMENT)
        .image_sharing_mode(image_sharing_mode)
        .queue_family_indices(&queue_family_indices)
        .pre_transform(support.capabilities.current_transform)
        .composite_alpha(vk::CompositeAlphaFlagsKHR::OPAQUE)
        .present_mode(present_mode)
        .clipped(true)
        .old_swapchain(vk::SwapchainKHR::null());

    data.swapchain = device.create_swapchain_khr(&info, None)?;
    data.swapchain_images = device.get_swapchain_images_khr(data.swapchain)?;
    data.swapchain_format = surface_format.format;
    data.swapchain_extent = extent;

    Ok(())
}

pub(super) unsafe fn create_swapchain_image_views(
    device: &Device,
    data: &mut AppData,
) -> Result<()> {
    data.swapchain_image_views = data
        .swapchain_images
        .iter()
        .map(|i| {
            let components = vk::ComponentMapping::builder()
                .r(vk::ComponentSwizzle::IDENTITY)
                .g(vk::ComponentSwizzle::IDENTITY)
                .b(vk::ComponentSwizzle::IDENTITY)
                .a(vk::ComponentSwizzle::IDENTITY);

            let subresource_range = vk::ImageSubresourceRange::builder()
                .aspect_mask(vk::ImageAspectFlags::COLOR)
                .base_mip_level(0)
                .level_count(1)
                .base_array_layer(0)
                .layer_count(1);

            let info = vk::ImageViewCreateInfo::builder()
                .image(*i)
                .view_type(vk::ImageViewType::_2D)
                .format(data.swapchain_format)
                .components(components)
                .subresource_range(subresource_range);

            device.create_image_view(&info, None)
        })
        .collect::<Result<Vec<_>, _>>()?;

    Ok(())
}