// SPDX-License-Identifier: AGPL-3.0-only

use crate::error::RendererError;
use ash::{Device, vk};

/// Groups all synchronization primitives for the renderer.
pub struct SyncPrimitives {
    /// Semaphores signaled when an image has been acquired from the swapchain and is ready for rendering.
    pub image_available: Vec<vk::Semaphore>,
    /// Semaphores signaled when rendering to a swapchain image is complete.
    pub render_finished: Vec<vk::Semaphore>,
    /// Fences used to synchronize CPU execution with GPU frame completion.
    pub in_flight: Vec<vk::Fence>,
}

/// Creates all synchronization primitives for the given number of frames and images.
pub fn create_sync_primitives(
    device: &Device,
    max_frames_in_flight: usize,
    image_count: usize,
) -> Result<SyncPrimitives, RendererError> {
    let semaphore_info = vk::SemaphoreCreateInfo::default();
    let fence_info = vk::FenceCreateInfo::default().flags(vk::FenceCreateFlags::SIGNALED);

    let mut image_available = Vec::with_capacity(max_frames_in_flight);
    let mut render_finished = Vec::with_capacity(image_count);
    let mut in_flight = Vec::with_capacity(max_frames_in_flight);

    for _ in 0..max_frames_in_flight {
        image_available.push(unsafe { device.create_semaphore(&semaphore_info, None)? });
        in_flight.push(unsafe { device.create_fence(&fence_info, None)? });
    }

    for _ in 0..image_count {
        render_finished.push(unsafe { device.create_semaphore(&semaphore_info, None)? });
    }

    Ok(SyncPrimitives {
        image_available,
        render_finished,
        in_flight,
    })
}

/// Destroys all synchronization primitives.
pub unsafe fn destroy_sync_primitives(device: &Device, sync: SyncPrimitives) {
    unsafe {
        for semaphore in sync.image_available {
            device.destroy_semaphore(semaphore, None);
        }
        for semaphore in sync.render_finished {
            device.destroy_semaphore(semaphore, None);
        }
        for fence in sync.in_flight {
            device.destroy_fence(fence, None);
        }
    }
}