Allow input capture & emulation being disabled (#158)

* Input capture and emulation can now be disabled and will prompt the user to enable again.

* Improved error handling to deliver more useful error messages

input-capture/src/macos.rs

@@ -1,8 +1,11 @@
-use crate::{error::MacOSInputCaptureCreationError, CaptureHandle, InputCapture, Position};
+use crate::{
+    error::MacOSInputCaptureCreationError, CaptureError, CaptureHandle, InputCapture, Position,
+};
+use async_trait::async_trait;
 use futures_core::Stream;
 use input_event::Event;
+use std::pin::Pin;
 use std::task::{Context, Poll};
-use std::{io, pin::Pin};
 
 pub struct MacOSInputCapture;
 
@@ -13,23 +16,28 @@ impl MacOSInputCapture {
 }
 
 impl Stream for MacOSInputCapture {
-    type Item = io::Result<(CaptureHandle, Event)>;
+    type Item = Result<(CaptureHandle, Event), CaptureError>;
 
     fn poll_next(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
         Poll::Pending
     }
 }
 
+#[async_trait]
 impl InputCapture for MacOSInputCapture {
-    fn create(&mut self, _id: CaptureHandle, _pos: Position) -> io::Result<()> {
+    async fn create(&mut self, _id: CaptureHandle, _pos: Position) -> Result<(), CaptureError> {
         Ok(())
     }
 
-    fn destroy(&mut self, _id: CaptureHandle) -> io::Result<()> {
+    async fn destroy(&mut self, _id: CaptureHandle) -> Result<(), CaptureError> {
         Ok(())
     }
 
-    fn release(&mut self) -> io::Result<()> {
+    async fn release(&mut self) -> Result<(), CaptureError> {
+        Ok(())
+    }
+
+    async fn terminate(&mut self) -> Result<(), CaptureError> {
         Ok(())
     }
 }