use crate::renderer::vulkan::{VkDevice, VkGraphicsPipeline, VkRenderPass, VkSwapchain};
use crate::renderer::Renderable;
use ash::vk;
use ash::vk::CommandBuffer;
use std::sync::Arc;

pub struct TriangleScene {
    pipeline: Option<VkGraphicsPipeline>,
}

impl TriangleScene {
    pub fn new() -> Self {
        Self { pipeline: None }
    }
}

impl Renderable for TriangleScene {
    fn init(&mut self, device: &Arc<VkDevice>, render_pass: &Arc<VkRenderPass>) -> anyhow::Result<()> {
        let pipeline = VkGraphicsPipeline::new(&device, &render_pass)?;
        self.pipeline = Some(pipeline);

        Ok(())
    }

    fn render(&self, device: &VkDevice, swapchain: &VkSwapchain, command_buffer: &CommandBuffer) -> anyhow::Result<()> {
        unsafe {
            device.handle.cmd_bind_pipeline(
                *command_buffer,
                vk::PipelineBindPoint::GRAPHICS,
                self.pipeline.as_ref().unwrap().pipeline,
            )
        };

        let viewport = vk::Viewport::default()
            .width(swapchain.surface_resolution.width as f32)
            .height(swapchain.surface_resolution.height as f32)
            .max_depth(1.0);

        unsafe { device.handle.cmd_set_viewport(*command_buffer, 0, &[viewport]) }

        let scissor = swapchain.surface_resolution.into();

        unsafe { device.handle.cmd_set_scissor(*command_buffer, 0, &[scissor]) }

        unsafe { device.handle.cmd_draw(*command_buffer, 3, 1, 0, 0) };

        Ok(())
    }
}