From 48cd360e3723d5b6c0b7aa9501e4502b2467a6a1 Mon Sep 17 00:00:00 2001
From: Khoa Vo <khoa@vietc.dev>
Date: Sat, 4 Jul 2026 16:51:50 +0700
Subject: [PATCH] =?UTF-8?q?Revert=20"fix:=20skip=20non-grabbed=20evdev=20o?=
 =?UTF-8?q?n=20X11,=20fall=20through=20to=20X11=20keymap=20capture"=20?=
 =?UTF-8?q?=E2=80=94=20X11=20keymap=20+=20uinput=20creates=20feedback=20lo?=
 =?UTF-8?q?op=20through=20XQueryKeymap?=
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---
 daemon/src/main.rs | 53 +++++++++++++++++++++++-----------------------
 1 file changed, 27 insertions(+), 26 deletions(-)

diff --git a/daemon/src/main.rs b/daemon/src/main.rs
index b5e621b..630eee3 100644
--- a/daemon/src/main.rs
+++ b/daemon/src/main.rs
@@ -1309,12 +1309,12 @@ fn run_with_evdev(
     _engine_enabled: Arc<AtomicBool>,
     display: display::DisplayServer,
 ) -> Result<(), Box<dyn std::error::Error>> {
-    let injector = create_injector(display)?;
+    let mut injector = create_injector(display)?;
 
     // Use the first device for grab (only one device can be grabbed at a time)
     let primary_idx = 0usize;
-    let mut grabbed = match devices.first() {
-        Some(_) if daemon.grab_enabled => match devices[primary_idx].0.grab() {
+    let mut grabbed = if daemon.grab_enabled && !devices.is_empty() {
+        match devices[primary_idx].0.grab() {
             Ok(()) => {
                 log_info("[vietc] Keyboard grabbed — race condition eliminated");
                 true
@@ -1324,28 +1324,27 @@ fn run_with_evdev(
                     "[vietc] Could not grab keyboard: {} (run as root for grab)",
                     e
                 ));
-                // On X11, fall through to keymap capture instead of non-grabbed evdev
-                #[cfg(feature = "x11")]
-                if display != display::DisplayServer::Wayland {
-                    log_info("[vietc] X11 detected — trying X11 keymap capture");
-                    return Ok(());
-                }
-                log_info("[vietc] Falling back to non-grabbing evdev mode (may have race)");
+                log_info("[vietc] Falling back to non-grabbing mode (may have race)");
                 false
             }
-        },
-        _ => {
-            log_info("[vietc] No keyboard devices available for grab");
-            false
         }
+    } else {
+        if !daemon.grab_enabled {
+            log_info("[vietc] Keyboard grab disabled (config grab = false)");
+            log_info("[vietc] Set grab = true in vietc.toml to enable (needs root)");
+        }
+        false
     };
 
-    // On X11 without evdev grab, use keymap capture instead of non-grabbed evdev.
-    // Reason: XTest backspace events feed back into evdev, corrupting the engine.
-    #[cfg(feature = "x11")]
-    if !grabbed && display != display::DisplayServer::Wayland {
-        log_info("[vietc] X11 without evdev grab — switching to X11 keymap capture");
-        return Ok(());
+    // Non-grabbed on X11: use XTest injection for fast, synchronous correction
+    if !grabbed {
+        #[cfg(feature = "x11")]
+        if display != display::DisplayServer::Wayland {
+            if let Ok(x11_inj) = vietc_protocol::x11_inject::X11Injector::new() {
+                injector = Box::new(x11_inj);
+                log_info("[vietc] Non-grabbed: using X11 injection (faster than uinput)");
+            }
+        }
     }
 
     let mut consumed_keys: HashSet<u16> = HashSet::new();
@@ -1380,18 +1379,20 @@ fn run_with_evdev(
         }
 
         if grabbed && idle_polls >= 3 && last_event_time.elapsed() > std::time::Duration::from_millis(200) {
-            #[cfg(feature = "x11")]
-            if display != display::DisplayServer::Wayland {
-                log_info("[vietc] No events via grab on X11 — exiting evdev for X11 keymap capture");
-                let _ = devices[primary_idx].0.ungrab();
-                return Ok(());
-            }
             log_info(
                 "[vietc] No events received via grab — releasing grab, continuing in non-grabbed evdev mode",
             );
             let _ = devices[primary_idx].0.ungrab();
             grabbed = false;
             log_info("[vietc] Non-grabbed mode: polling all evdev devices for keystrokes");
+            // Switch to XTest injection for fast synchronous non-grabbed correction
+            #[cfg(feature = "x11")]
+            if display != display::DisplayServer::Wayland {
+                if let Ok(x11_inj) = vietc_protocol::x11_inject::X11Injector::new() {
+                    injector = Box::new(x11_inj);
+                    log_info("[vietc] Non-grabbed: using X11 injection (faster than uinput)");
+                }
+            }
             continue;
         }