add long-press + notif based mode switching

oooooh boy, this is looking pretty slick. I'm kind-of impressed I was
able to throw this together in ~2 days of post-work hacking (though I
guess they were some pretty late-nights...)

There's really only one feature left that I _need_ to implement, which
is the on-disk persistence for selected mode. That shouldn't be too
tricky though...

src/controller/controls/dpad.rs

@@ -3,7 +3,7 @@ use std::sync::mpsc;
 use std::thread::JoinHandle;
 use std::time::Duration;
 
-use crate::controller::ControlMode;
+use crate::controller::{ControlMode, ControlModeMeta};
 use crate::dial_device::DialHaptics;
 use crate::fake_input::FakeInput;
 use crate::DynResult;
@@ -123,6 +123,13 @@ impl DPad {
 }
 
 impl ControlMode for DPad {
+    fn meta(&self) -> ControlModeMeta {
+        ControlModeMeta {
+            name: "Paddle",
+            icon: "input-gaming",
+        }
+    }
+
     fn on_start(&mut self, haptics: &DialHaptics) -> DynResult<()> {
         haptics.set_mode(false, Some(3600))?;
         Ok(())

src/controller/controls/media.rs

@@ -1,4 +1,4 @@
-use crate::controller::ControlMode;
+use crate::controller::{ControlMode, ControlModeMeta};
 use crate::dial_device::DialHaptics;
 use crate::fake_input::FakeInput;
 use crate::DynResult;
@@ -18,6 +18,13 @@ impl Media {
 }
 
 impl ControlMode for Media {
+    fn meta(&self) -> ControlModeMeta {
+        ControlModeMeta {
+            name: "Media",
+            icon: "applications-multimedia",
+        }
+    }
+
     fn on_start(&mut self, haptics: &DialHaptics) -> DynResult<()> {
         haptics.set_mode(false, Some(36))?;
         Ok(())

src/controller/controls/null.rs

@@ -1,16 +1,15 @@
-use crate::controller::ControlMode;
+use crate::controller::{ControlMode, ControlModeMeta};
 use crate::dial_device::DialHaptics;
 use crate::DynResult;
 
-pub struct Null {}
-
-impl Null {
-    pub fn new() -> Null {
-        Null {}
+impl ControlMode for () {
+    fn meta(&self) -> ControlModeMeta {
+        ControlModeMeta {
+            name: "null",
+            icon: "",
+        }
     }
-}
 
-impl ControlMode for Null {
     fn on_start(&mut self, haptics: &DialHaptics) -> DynResult<()> {
         haptics.set_mode(false, Some(0))?;
         Ok(())

src/controller/controls/scroll_zoom.rs

@@ -1,5 +1,5 @@
 use crate::common::action_notification;
-use crate::controller::ControlMode;
+use crate::controller::{ControlMode, ControlModeMeta};
 use crate::dial_device::DialHaptics;
 use crate::fake_input::{FakeInput, ScrollStep};
 use crate::DynResult;
@@ -26,6 +26,13 @@ const ZOOM_SENSITIVITY: u16 = 36;
 const SCROLL_SENSITIVITY: u16 = 90;
 
 impl ControlMode for ScrollZoom {
+    fn meta(&self) -> ControlModeMeta {
+        ControlModeMeta {
+            name: "Scroll/Zoom",
+            icon: "input-mouse",
+        }
+    }
+
     fn on_start(&mut self, haptics: &DialHaptics) -> DynResult<()> {
         haptics.set_mode(false, Some(SCROLL_SENSITIVITY))?;
         Ok(())
@@ -43,7 +50,7 @@ impl ControlMode for ScrollZoom {
             action_notification("Zoom Mode", "zoom-in")?;
             haptics.set_mode(false, Some(ZOOM_SENSITIVITY))?;
         } else {
-            action_notification("ScrollZoom Mode", "input-mouse")?;
+            action_notification("Scroll Mode", "input-mouse")?;
             haptics.set_mode(false, Some(SCROLL_SENSITIVITY))?;
         }
 

src/controller/controls/volume.rs

@@ -1,4 +1,4 @@
-use crate::controller::ControlMode;
+use crate::controller::{ControlMode, ControlModeMeta};
 use crate::dial_device::DialHaptics;
 use crate::fake_input::FakeInput;
 use crate::DynResult;
@@ -18,8 +18,15 @@ impl Volume {
 }
 
 impl ControlMode for Volume {
+    fn meta(&self) -> ControlModeMeta {
+        ControlModeMeta {
+            name: "Volume",
+            icon: "audio-volume-high",
+        }
+    }
+
     fn on_start(&mut self, haptics: &DialHaptics) -> DynResult<()> {
-        haptics.set_mode(false, Some(36 * 2))?;
+        haptics.set_mode(true, Some(36 * 2))?;
         Ok(())
     }