use crate::error::Result;
use xcb::{
    x::{AllocColor, Colormap, FreeColors},
    Connection as RawConnection,
};

/// Caches colours in an X11 color map.
pub struct Colours {
    #[allow(unused)] // Make sure the colour map we're using doesn't go anywhere
    cmap: Colormap,
    border_normal: u32,
    border_focused: u32,
}

impl Colours {
    /// Load the colours into the given colour map
    pub fn new_with(conn: &RawConnection, cmap: Colormap) -> Result<Self> {
        // TODO: Move these colours out to config.rs
        let (border_normal, border_focused) = (
            conn.wait_for_reply(conn.send_request(&AllocColor {
                cmap,
                red: 0,
                green: 0,
                blue: 0,
            }))?,
            conn.wait_for_reply(conn.send_request(&AllocColor {
                cmap,
                red: u16::MAX,
                green: 0,
                blue: u16::MAX,
            }))?,
        );

        Ok(Self {
            cmap,
            border_normal: border_normal.pixel(),
            border_focused: border_focused.pixel(),
        })
    }

    /// Get the pixel ID of the colour for an unfocused window's border.
    pub const fn border_normal(&self) -> u32 {
        self.border_normal
    }

    /// Get the pixel ID of the colour for a focused window's border.
    pub const fn border_focused(&self) -> u32 {
        self.border_focused
    }

    /// Free the associated resources to avoid leaking them.
    /// This object must not be used again after this method is called, as all resources will be invalid.
    pub unsafe fn free(&self, conn: &RawConnection) {
        conn.send_request(&FreeColors {
            cmap: self.cmap,
            plane_mask: 0,
            pixels: &[self.border_normal, self.border_focused],
        });
    }
}