Fix Unicode injection: ydotoold + xclip fallback + input logging

- Start ydotoold automatically so ydotool can handle Vietnamese chars
- Fix xclip clipboard to run as SUDO_USER when daemon is root
- Add detailed input logging for easier debugging

daemon/src/main.rs

@@ -130,6 +130,7 @@ impl Daemon {
         let mut commands = Vec::new();
 
         if let Some(event) = self.engine.process_key(ch) {
+            eprintln!("[vietc] key='{}' buf='{}' -> {:?}", ch, self.engine.buffer(), event);
             match event {
                 EngineEvent::Flush(text) => {
                     commands.push(OutputCommand::Type(text));
@@ -151,6 +152,8 @@ impl Daemon {
                     commands.push(OutputCommand::Type(restored));
                 }
             }
+        } else {
+            eprintln!("[vietc] key='{}' -> (no event, buf='{}')", ch, self.engine.buffer());
         }
 
         commands
@@ -576,20 +579,19 @@ fn execute_commands(injector: &dyn vietc_protocol::KeyInjector, commands: &[Outp
     for cmd in commands {
         match cmd {
             OutputCommand::Backspace(count) => {
-                // The engine adds +1 to account for the current character key.
-                // With grabbing that key was never forwarded to the app, so
-                // we subtract 1. Without grab, the key WAS forwarded, so we
-                // use the full count.
                 let adjusted = if grabbed { count.saturating_sub(1) } else { *count };
+                eprintln!("[vietc] cmd: Backspace({}) -> adjusted={}", count, adjusted);
                 pending_backspaces += adjusted;
             }
             OutputCommand::Type(text) => {
+                eprintln!("[vietc] cmd: Type(\"{}\")", text);
                 pending_text.push_str(text);
             }
         }
     }
 
     if pending_backspaces > 0 || !pending_text.is_empty() {
+        eprintln!("[vietc] inject: BS={} text=\"{}\"", pending_backspaces, pending_text);
         injector.inject_replacement(pending_backspaces, &pending_text);
     }
     injector.flush();

protocol/src/uinput_monitor.rs

@@ -24,7 +24,23 @@ unsafe impl Send for UinputInjector {}
 unsafe impl Sync for UinputInjector {}
 
 impl UinputInjector {
+    fn start_ydotoold() {
+        // ydotoold must be running for ydotool to handle Unicode characters.
+        // ydotool in direct mode crashes with "no matching keycode" for
+        // non-ASCII chars. Start it once; ignore failure (daemon may already
+        // exist).
+        let _ = std::process::Command::new("ydotoold")
+            .arg("--fork")
+            .stdout(std::process::Stdio::null())
+            .stderr(std::process::Stdio::null())
+            .spawn();
+        // Give it a moment to start
+        std::thread::sleep(std::time::Duration::from_millis(200));
+    }
+
     pub fn new(name: &str) -> Result<Self, Box<dyn std::error::Error>> {
+        Self::start_ydotoold();
+
         let file = OpenOptions::new()
             .read(true)
             .write(true)
@@ -332,7 +348,30 @@ impl UinputInjector {
         {
             return true;
         }
-        // Try xclip (X11)
+        // Try xclip (X11). When root, run as SUDO_USER so it can connect to X.
+        let xclip_result = if is_root {
+            if let Ok(sudo_user) = std::env::var("SUDO_USER") {
+                let display = std::env::var("DISPLAY").unwrap_or_default();
+                let mut cmd = std::process::Command::new("sudo");
+                cmd.args(["-u", &sudo_user, "env"]);
+                if !display.is_empty() {
+                    cmd.arg(format!("DISPLAY={}", display));
+                }
+                cmd.arg("xclip");
+                cmd.args(["-selection", "clipboard"]);
+                cmd.stdin(std::process::Stdio::piped())
+                    .spawn()
+                    .and_then(|mut child| {
+                        use std::io::Write;
+                        child.stdin.take().unwrap().write_all(s.as_bytes())?;
+                        child.wait()
+                    })
+                    .map(|status| status.success())
+                    .unwrap_or(false)
+            } else {
+                false
+            }
+        } else {
             std::process::Command::new("xclip")
                 .args(["-selection", "clipboard"])
                 .stdin(std::process::Stdio::piped())
@@ -344,6 +383,13 @@ impl UinputInjector {
                 })
                 .map(|status| status.success())
                 .unwrap_or(false)
+        };
+
+        if xclip_result {
+            return true;
+        }
+
+        false
     }
 
     /// Send Ctrl+V through our uinput device.