use super::*;
use crate::{VALIDATION_ENABLED, VALIDATION_LAYER};

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)?;

    Ok(())
}

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 extension_names = if instance
        .enumerate_device_extension_properties(data.physical_device, None)?
        .iter()
        .any(|e| e.extension_name == vk::KHR_PORTABILITY_SUBSET_EXTENSION.name)
    {
        vec![vk::KHR_PORTABILITY_SUBSET_EXTENSION.name.as_ptr()]
    } else {
        vec![]
    };

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

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

    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)
}