refactor: break down handle_input into smaller methods in src/gui/input.rs (#67)

Extract sections from the long `handle_input` function into smaller,
context-specific helper methods such as `handle_hotkey_assignment`,
`handle_toggles`, `handle_playback_and_focus`, `handle_file_playback`,
`handle_navigation`, and `handle_hotkey_triggers`. This significantly
improves the maintainability and readability of `src/gui/input.rs`
while preserving original functionality.

In addition, ran `cargo clippy --fix` on the project to resolve a few
other minor health issues, like collapsing nested `if` statements and
reducing unnecessary allocations.

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>

src/types/audio_player.rs

@@ -106,7 +106,7 @@ impl AudioPlayer {
 
     fn abort_link_thread(&mut self) {
         if let Some(sender) = &self.input_link_sender {
-            if let Ok(_) = sender.send(Terminate {}) {
+            if sender.send(Terminate {}).is_ok() {
                 println!("Sent terminate signal to input link thread");
                 self.input_link_sender = None;
             } else {
@@ -117,7 +117,7 @@ impl AudioPlayer {
 
     fn abort_player_link_thread(&mut self) {
         if let Some(sender) = &self.player_link_sender {
-            if let Ok(_) = sender.send(Terminate {}) {
+            if sender.send(Terminate {}).is_ok() {
                 println!("Sent terminate signal to player link thread");
                 self.player_link_sender = None;
             } else {
@@ -254,12 +254,12 @@ impl AudioPlayer {
     pub fn get_volume(&mut self, id: Option<u32>) -> Option<f32> {
         if let Some(id) = id {
             if let Some(sound) = self.tracks.get_mut(&id) {
-                return Some(sound.sink.volume());
+                Some(sound.sink.volume())
             } else {
-                return None;
+                None
             }
         } else {
-            return Some(self.volume);
+            Some(self.volume)
         }
     }
 
@@ -443,10 +443,10 @@ impl AudioPlayer {
             if let Some(sound) = self.tracks.get(&id) {
                 let path = sound.path.clone();
                 let handle = tokio::task::spawn_blocking(move || {
-                    if let Ok(file) = fs::File::open(&path) {
-                        if let Ok(source) = Decoder::try_from(file) {
-                            return Some((id, source));
-                        }
+                    if let Ok(file) = fs::File::open(&path)
+                        && let Ok(source) = Decoder::try_from(file)
+                    {
+                        return Some((id, source));
                     }
                     None
                 });
@@ -455,13 +455,12 @@ impl AudioPlayer {
         }
 
         for handle in restart_futures {
-            if let Ok(res) = handle.await {
-                if let Some((id, source)) = res {
-                    if let Some(sound) = self.tracks.get_mut(&id) {
-                        sound.sink.append(source);
-                        sound.sink.play();
-                    }
-                }
+            if let Ok(res) = handle.await
+                && let Some((id, source)) = res
+                && let Some(sound) = self.tracks.get_mut(&id)
+            {
+                sound.sink.append(source);
+                sound.sink.play();
             }
         }
 

src/types/commands.rs

@@ -673,7 +673,7 @@ impl Executable for PlayHotkeyCommand {
         if let Some(cmd) = parse_command(&action) {
             cmd.execute().await
         } else {
-            Response::new(false, "Unknown command in hotkey slot".to_string())
+            Response::new(false, "Unknown command in hotkey slot")
         }
     }
 }

src/types/config.rs

@@ -13,10 +13,10 @@ impl DaemonConfig {
     pub fn save_to_file(&self) -> Result<(), Box<dyn Error>> {
         let config_path = get_config_path()?.join("daemon.json");
 
-        if let Some(config_dir) = config_path.parent() {
-            if !config_path.exists() {
-                fs::create_dir_all(config_dir)?;
-            }
+        if let Some(config_dir) = config_path.parent()
+            && !config_path.exists()
+        {
+            fs::create_dir_all(config_dir)?;
         }
 
         let config_json = serde_json::to_string_pretty(self)?;
@@ -68,10 +68,10 @@ impl GuiConfig {
     pub fn save_to_file(&mut self) -> Result<(), Box<dyn Error>> {
         let config_path = get_config_path()?.join("gui.json");
 
-        if let Some(config_dir) = config_path.parent() {
-            if !config_path.exists() {
-                fs::create_dir_all(config_dir)?;
-            }
+        if let Some(config_dir) = config_path.parent()
+            && !config_path.exists()
+        {
+            fs::create_dir_all(config_dir)?;
         }
 
         // Do not save scale factor if user does not want to