image-copy: Use abstraction that's now provided by Smithay

This doesn't change much, since the Smithay implementation is based on
the `cosmic-comp` version, but made more generic. We provide our own
implementation for our workspace capture protocol, but otherwise Smithay
handles the boilerplate now.

This should not cause any change in behavior.

src/wayland/handlers/image_capture_source.rs

@@ -1,4 +1,59 @@
-use crate::state::State;
-use crate::wayland::protocols::image_capture_source::delegate_image_capture_source;
+// SPDX-License-Identifier: GPL-3.0-only
 
-delegate_image_capture_source!(State);
+use crate::{
+    state::State,
+    wayland::protocols::{
+        image_capture_source::{ImageCaptureSourceKind, delegate_cosmic_image_capture_source},
+        toplevel_info::window_from_ext,
+    },
+};
+use smithay::{
+    output::Output,
+    wayland::{
+        foreign_toplevel_list::ForeignToplevelHandle,
+        image_capture_source::{
+            ImageCaptureSource, ImageCaptureSourceHandler, OutputCaptureSourceHandler,
+            OutputCaptureSourceState, ToplevelCaptureSourceHandler, ToplevelCaptureSourceState,
+        },
+    },
+};
+
+impl ImageCaptureSourceHandler for State {
+    fn source_destroyed(&mut self, _source: ImageCaptureSource) {}
+}
+
+impl OutputCaptureSourceHandler for State {
+    fn output_capture_source_state(&mut self) -> &mut OutputCaptureSourceState {
+        &mut self.common.output_capture_source_state
+    }
+
+    fn output_source_created(&mut self, source: ImageCaptureSource, output: &Output) {
+        source
+            .user_data()
+            .insert_if_missing(|| ImageCaptureSourceKind::Output(output.downgrade()));
+    }
+}
+
+impl ToplevelCaptureSourceHandler for State {
+    fn toplevel_capture_source_state(&mut self) -> &mut ToplevelCaptureSourceState {
+        &mut self.common.toplevel_capture_source_state
+    }
+
+    fn toplevel_source_created(
+        &mut self,
+        source: ImageCaptureSource,
+        toplevel: &ForeignToplevelHandle,
+    ) {
+        let data = match window_from_ext(self, toplevel) {
+            Some(toplevel) => ImageCaptureSourceKind::Toplevel(toplevel.clone()),
+            None => ImageCaptureSourceKind::Destroyed,
+        };
+        source.user_data().insert_if_missing(|| data);
+    }
+}
+
+smithay::delegate_image_capture_source!(State);
+smithay::delegate_output_capture_source!(State);
+smithay::delegate_toplevel_capture_source!(State);
+
+delegate_cosmic_image_capture_source!(State);