From a0a324301b23d8003e4d116f9cc1bd07353f587f Mon Sep 17 00:00:00 2001
From: Buj <buj@buj-dev.ru>
Date: Sun, 3 Sep 2023 21:34:13 +0700
Subject: [PATCH] Raw window handle (not implemented for now)

---
 Cargo.toml              |  7 +++++++
 src/lok.rs              | 31 ++++++++++++++++++++++++++++++-
 src/native/linux/mod.rs | 10 ++++++++++
 src/native/macos/mod.rs | 10 ++++++++++
 src/window.rs           | 14 ++++++++++++++
 5 files changed, 71 insertions(+), 1 deletion(-)

diff --git a/Cargo.toml b/Cargo.toml
index cd58fb4..c0299fc 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,3 +7,10 @@ license = "MIT/Apache-2.0"
 authors = ["The Loki Authors"]
 keywords = ["windowing"]
 categories = ["gui"]
+
+[features]
+default = ["raw-window-handle"]
+raw-window-handle = ["dep:raw-window-handle"]
+
+[dependencies]
+raw-window-handle = { version = "0.5.2", optional = true }
diff --git a/src/lok.rs b/src/lok.rs
index 85b0892..8072520 100644
--- a/src/lok.rs
+++ b/src/lok.rs
@@ -42,6 +42,19 @@ pub trait LokinitBackend {
     fn fetch_monitors(&mut self) -> Vec<Monitor> {
         unimplemented!()
     }
+
+    #[cfg(feature = "raw-window-handle")]
+    fn raw_display_handle(&self) -> raw_window_handle::RawDisplayHandle;
+
+    #[cfg(feature = "raw-window-handle")]
+    fn raw_window_handle_for(&self, window_handle: WindowHandle) -> raw_window_handle::RawWindowHandle;
+}
+
+#[cfg(feature = "raw-window-handle")]
+unsafe impl raw_window_handle::HasRawDisplayHandle for dyn LokinitBackend {
+    fn raw_display_handle(&self) -> raw_window_handle::RawDisplayHandle {
+        self.raw_display_handle()
+    }
 }
 
 thread_local! {
@@ -73,7 +86,13 @@ pub fn init_backend<B: LokinitBackend + 'static>() {
 pub fn with<R>(callback: impl FnOnce(&mut dyn LokinitBackend) -> R) -> R {
     INSTANCE.with(|instance| {
         let mut instance = instance.borrow_mut();
-        let instance = instance.as_deref_mut().expect("Lokinit is not initialized");
+        let instance = instance
+            .as_deref_mut()
+            .expect(if INITIALIZED.load(Ordering::Relaxed) {
+                "Accessing Lokinit from a non-main thread"
+            } else {
+                "Lokinit is not initialized"
+            });
         (callback)(instance)
     })
 }
@@ -93,3 +112,13 @@ pub fn poll_event() -> Option<Event> {
 pub fn fetch_monitors() -> Vec<Monitor> {
     with(|instance| instance.fetch_monitors())
 }
+
+#[cfg(feature = "raw-window-handle")]
+pub fn raw_display_handle() -> raw_window_handle::RawDisplayHandle {
+    with(|instance| instance.raw_display_handle())
+}
+
+#[cfg(feature = "raw-window-handle")]
+pub fn raw_window_handle(window_handle: WindowHandle) -> raw_window_handle::RawWindowHandle {
+    with(|instance| instance.raw_window_handle_for(window_handle))
+}
diff --git a/src/native/linux/mod.rs b/src/native/linux/mod.rs
index f7552e0..c789050 100644
--- a/src/native/linux/mod.rs
+++ b/src/native/linux/mod.rs
@@ -115,4 +115,14 @@ impl LokinitBackend for LinuxBackend {
             Self::Wayland(_wl) => todo!(),
         }
     }
+
+    #[cfg(feature = "raw-window-handle")]
+    fn raw_display_handle(&self) -> raw_window_handle::RawDisplayHandle {
+        todo!()
+    }
+
+    #[cfg(feature = "raw-window-handle")]
+    fn raw_window_handle_for(&self, window_handle: WindowHandle) -> raw_window_handle::RawWindowHandle {
+        todo!()
+    }
 }
diff --git a/src/native/macos/mod.rs b/src/native/macos/mod.rs
index ac5fbe5..2d13b85 100644
--- a/src/native/macos/mod.rs
+++ b/src/native/macos/mod.rs
@@ -45,4 +45,14 @@ impl LokinitBackend for MacosBackend {
     fn poll_event(&mut self) -> Option<Event> {
         unsafe { ffi_swift::update() }.try_into().ok()
     }
+
+    #[cfg(feature = "raw-window-handle")]
+    fn raw_display_handle(&self) -> raw_window_handle::RawDisplayHandle {
+        todo!()
+    }
+
+    #[cfg(feature = "raw-window-handle")]
+    fn raw_window_handle_for(&self, window_handle: WindowHandle) -> raw_window_handle::RawWindowHandle {
+        todo!()
+    }
 }
diff --git a/src/window.rs b/src/window.rs
index f86fd85..82cffac 100644
--- a/src/window.rs
+++ b/src/window.rs
@@ -104,3 +104,17 @@ impl WindowBuilder {
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct WindowHandle(pub(crate) usize);
+
+#[cfg(feature = "raw-window-handle")]
+unsafe impl raw_window_handle::HasRawWindowHandle for WindowHandle {
+    fn raw_window_handle(&self) -> raw_window_handle::RawWindowHandle {
+        crate::lok::raw_window_handle(*self)
+    }
+}
+
+#[cfg(feature = "raw-window-handle")]
+unsafe impl raw_window_handle::HasRawDisplayHandle for WindowHandle {
+    fn raw_display_handle(&self) -> raw_window_handle::RawDisplayHandle {
+        crate::lok::raw_display_handle()
+    }
+}