use bitflags::bitflags;use thiserror::Error; use crate::Pixels; /// The layer the surface is rendered on. Multiple surfaces can share a layer, and ordering within/// a single layer is undefined.#[derive(Copy, Clone, Debug, Default, PartialEq, Eq)]pub enum Layer {    /// The background layer, typically used for wallpapers.    Background,     /// The bottom layer.    Bottom,     /// The top layer, typically used for fullscreen windows.    Top,     /// The overlay layer, used for surfaces that should always be on top.    #[default]    Overlay,} bitflags! {    /// Screen anchor point for layer_shell surfaces. These can be used in any combination, e.g.    /// specifying `Anchor::LEFT | Anchor::RIGHT` will stretch the surface across the width of the    /// screen.    #[derive(Copy, Clone, Debug, Default, PartialEq, Eq)]    pub struct Anchor: u32 {        /// Anchor to the top edge of the screen.        const TOP = 1;        /// Anchor to the bottom edge of the screen.        const BOTTOM = 2;        /// Anchor to the left edge of the screen.        const LEFT = 4;        /// Anchor to the right edge of the screen.        const RIGHT = 8;    }} /// Keyboard interactivity mode for the layer_shell surfaces.#[derive(Copy, Clone, Debug, Default, PartialEq, Eq)]pub enum KeyboardInteractivity {    /// No keyboard inputs will be delivered to the surface and it won't be able to receive    /// keyboard focus.    None,     /// The surface will receive exclusive keyboard focus as long as it is above the shell surface    /// layer, and no other layer_shell surfaces are above it.    Exclusive,     /// The surface can be focused similarly to a normal window.    #[default]    OnDemand,} /// Options for creating a layer_shell window.#[derive(Clone, Debug, Default, PartialEq, Eq)]pub struct LayerShellOptions {    /// The namespace for the surface, mostly used by compositors to apply rules, can not be    /// changed after the surface is created.    pub namespace: String,    /// The layer the surface is rendered on.    pub layer: Layer,    /// The anchor point of the surface.    pub anchor: Anchor,    /// Requests that the compositor avoids occluding an area with other surfaces.    pub exclusive_zone: Option<Pixels>,    /// The anchor point of the exclusive zone, will be determined using the anchor if left    /// unspecified.    pub exclusive_edge: Option<Anchor>,    /// Margins between the surface and its anchor point(s).    /// Specified in CSS order: top, right, bottom, left.    pub margin: Option<(Pixels, Pixels, Pixels, Pixels)>,    /// How keyboard events should be delivered to the surface.    pub keyboard_interactivity: KeyboardInteractivity,} /// An error indicating that an action failed because the compositor doesn't support the required/// layer_shell protocol.#[derive(Debug, Error)]#[error("Compositor doesn't support zwlr_layer_shell_v1")]pub struct LayerShellNotSupportedError;