feat: dnd integration

dnd/src/lib.rs

@@ -0,0 +1,126 @@
+use std::{
+    borrow::Cow,
+    ffi::c_void,
+    sync::{mpsc::SendError, Arc},
+};
+
+use bitflags::bitflags;
+
+#[cfg(all(
+    unix,
+    not(any(
+        target_os = "macos",
+        target_os = "ios",
+        target_os = "android",
+        target_os = "emscripten",
+        target_os = "redox"
+    ))
+))]
+#[path = "platform/linux.rs"]
+pub mod platform;
+
+bitflags! {
+    // Attributes can be applied to flags types
+    #[repr(transparent)]
+    #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+    pub struct DndAction: u32 {
+        const Copy = 0b00000001;
+        const Move = 0b00000010;
+        const Ask = 0b00000100;
+    }
+}
+
+#[derive(Debug)]
+pub enum DndEvent<T> {
+    /// Dnd Offer event with the corresponding destination rectangle ID.
+    Offer(Option<u128>, OfferEvent<T>),
+    /// Dnd Source event.
+    Source(SourceEvent),
+}
+
+#[derive(Debug)]
+pub enum SourceEvent {
+    /// DnD operation ended.
+    Finished,
+    /// DnD Cancelled.
+    Cancelled,
+    /// DnD action chosen by the compositor.
+    Action(DndAction),
+    /// Mime accepted by destination.
+    /// If [`None`], no mime types are accepted.
+    Mime(Option<String>),
+    /// DnD Dropped. The operation is still ongoing until receiving a
+    /// [`SourceEvent::Finished`] event.
+    Dropped,
+}
+
+#[derive(Debug)]
+pub enum OfferEvent<T> {
+    Enter {
+        x: f64,
+        y: f64,
+        mime_types: Vec<String>,
+        surface: T,
+    },
+    Motion {
+        x: f64,
+        y: f64,
+    },
+    /// The offer is no longer on a DnD destination.
+    LeaveDestination,
+    /// The offer has left the surface.
+    Leave,
+    /// An offer was dropped
+    Drop,
+    /// If the selected action is ASK, the user must be presented with a
+    /// choice. [`Clipboard::set_action`] should then be called before data
+    /// can be requested and th DnD operation can be finished.
+    SelectedAction(DndAction),
+    Data {
+        data: Vec<u8>,
+        mime_type: String,
+    },
+}
+
+/// A rectangle with a logical location and size relative to a [`DndSurface`]
+#[derive(Debug, Default, Clone)]
+pub struct Rectangle {
+    pub x: f64,
+    pub y: f64,
+    pub width: f64,
+    pub height: f64,
+}
+
+pub trait Sender<T> {
+    /// Send an event in the channel
+    fn send(&self, t: DndEvent<T>) -> Result<(), SendError<DndEvent<T>>>;
+}
+
+pub trait RawSurface {
+    /// # Safety
+    ///
+    /// returned pointer must be a valid pointer to the underlying surface, and it must
+    /// remain valid for as long as `RawSurface` object is alive.
+    unsafe fn get_ptr(&mut self) -> *mut c_void;
+}
+
+/// A rectangle with a logical location and size relative to a [`DndSurface`]
+#[derive(Debug, Clone)]
+pub struct DndDestinationRectangle {
+    /// A unique ID
+    pub id: u128,
+    /// The rectangle representing this destination.
+    pub rectangle: Rectangle,
+    /// Accepted mime types in this rectangle
+    pub mime_types: Vec<Cow<'static, str>>,
+    /// Accepted actions in this rectangle
+    pub actions: DndAction,
+    /// Prefered action in this rectangle
+    pub preferred: DndAction,
+}
+
+#[derive(Clone)]
+pub struct DndSurface(pub Arc<Box<dyn RawSurface + 'static + Send + Sync>>);
+
+#[derive(Clone)]
+pub struct DataWrapper<T>(pub T);