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use super::{ClonerOverlay, ClonerOverlayAt, Image, ImageUtils, Overlay, OverlayAt};
#[derive(Clone, Debug)]
pub enum ImageHolder<const CHANNELS: usize> {
    Borrow(Image<&'static [u8], CHANNELS>),
    Own(Image<Box<[u8]>, CHANNELS>),
}

impl<const CHANNELS: usize> ImageHolder<CHANNELS> {
    #[must_use]
    pub fn own(self) -> Image<Box<[u8]>, CHANNELS> {
        match self {
            Self::Own(x) => x,
            Self::Borrow(x) => x.boxed(),
        }
    }
}

impl<const CHANNELS: usize> ImageHolder<CHANNELS> {
    #[must_use]
    #[inline]
    pub fn borrow(&self) -> Image<&[u8], CHANNELS> {
        match self {
            Self::Own(x) => x.as_ref(),
            Self::Borrow(x) => *x,
        }
    }

    #[must_use]
    #[inline]
    pub fn borrow_mut(&mut self) -> Image<&mut [u8], CHANNELS> {
        match self {
            Self::Own(x) => x.as_mut(),
            Self::Borrow(x) => {
                *self = Self::from(x.boxed());
                self.borrow_mut()
            }
        }
    }
}

macro_rules! make {
    ($me: ident . $fn:ident($($argv:expr),*)) => {
        match $me {
            Self::Own(v) => {
                #[allow(unused_unsafe)]
                unsafe { v.as_mut().$fn($($argv,)*) };
                $me
            }
            Self::Borrow(v) => {
                #[allow(unused_unsafe)]
                { *$me = Self::from(unsafe { v.cloner().$fn($($argv,)*).boxed() }) };
                $me
            }
        }
    };
}

impl OverlayAt<ImageHolder<4>> for ImageHolder<4> {
    unsafe fn overlay_at(&mut self, with: &ImageHolder<4>, x: u32, y: u32) -> &mut Self {
        make!(self.overlay_at(&with.borrow(), x, y))
    }
}

impl OverlayAt<Image<&[u8], 3>> for ImageHolder<3> {
    unsafe fn overlay_at(&mut self, with: &Image<&[u8], 3>, x: u32, y: u32) -> &mut Self {
        make!(self.overlay_at(with, x, y))
    }
}

impl Overlay<Image<&[u8], 4>> for ImageHolder<3> {
    unsafe fn overlay(&mut self, with: &Image<&[u8], 4>) -> &mut Self {
        make!(self.overlay(with))
    }
}

impl Overlay<ImageHolder<4>> for ImageHolder<3> {
    unsafe fn overlay(&mut self, with: &ImageHolder<4>) -> &mut Self {
        make!(self.overlay(&with.borrow()))
    }
}

impl Overlay<ImageHolder<4>> for ImageHolder<4> {
    unsafe fn overlay(&mut self, with: &Self) -> &mut Self {
        make!(self.overlay(&with.borrow()))
    }
}

impl ImageUtils for ImageHolder<4> {
    fn tint(&mut self, color: (u8, u8, u8)) -> &mut Self {
        self.borrow_mut().tint(color);
        self
    }

    unsafe fn rotate(&mut self, times: u8) -> &mut Self {
        match times {
            2 => make!(self.rot_180()),
            1 => make!(self.rot_90()),
            3 => make!(self.rot_270()),
            _ => self,
        }
    }

    fn shadow(&mut self) -> &mut Self {
        self.borrow_mut().shadow();
        self
    }
}

impl<const CHANNELS: usize> From<Image<&'static [u8], CHANNELS>> for ImageHolder<CHANNELS> {
    fn from(value: Image<&'static [u8], CHANNELS>) -> Self {
        Self::Borrow(value)
    }
}

impl<const CHANNELS: usize> From<Image<Box<[u8]>, CHANNELS>> for ImageHolder<CHANNELS> {
    fn from(value: Image<Box<[u8]>, CHANNELS>) -> Self {
        Self::Own(value)
    }
}