use uefi::proto::console::gop::{BltOp, BltPixel, BltRegion, GraphicsOutput};

extern crate alloc;
use alloc::vec;
use alloc::vec::Vec;
use uefi::Error;

pub struct Buffer {
    pub width: usize,
    pub height: usize,
    pixels: Vec<BltPixel>,
}

impl Buffer {
    /// Create a new `Buffer`.
    pub fn new(width: usize, height: usize) -> Self {
        Buffer {
            width,
            height,
            pixels: vec![BltPixel::new(0, 0, 0); width * height],
        }
    }

    /// Get a single pixel.
    pub fn get_pixel(&mut self, x: usize, y: usize) -> Option<&mut BltPixel> {
        self.pixels.get_mut(y * self.width + x)
    }

    /// Set a single pixel.
    pub fn set_pixel(&mut self, x: usize, y: usize, pixel: BltPixel) {
        self.pixels[y * self.width + x] = pixel;
    }

    /// Blit the buffer to the framebuffer.
    pub fn blit(&self, gop: &mut GraphicsOutput) -> Result<(), Error> {
        gop.blt(BltOp::BufferToVideo {
            buffer: &self.pixels,
            src: BltRegion::Full,
            dest: (0, 0),
            dims: (self.width, self.height),
        })
    }

    /// Update only a pixel to the framebuffer.
    fn blit_pixel(&self, gop: &mut GraphicsOutput, coords: (usize, usize)) -> Result<(), Error> {
        gop.blt(BltOp::BufferToVideo {
            buffer: &self.pixels,
            src: BltRegion::SubRectangle {
                coords,
                px_stride: self.width,
            },
            dest: coords,
            dims: (1, 1),
        })
    }
}