core: note when keyCallback processed the input

src/Surface.zig

@@ -1022,13 +1022,19 @@ pub fn charCallback(self: *Surface, codepoint: u21) !void {
     try self.io_thread.wakeup.notify();
 }
 
+/// Called for a single key event.
+///
+/// This will return true if the key was handled/consumed. In that case,
+/// the caller doesn't need to call a subsequent `charCallback` for the
+/// same event. However, the caller can call `charCallback` if they want,
+/// the surface will retain state to ensure the event is ignored.
 pub fn keyCallback(
     self: *Surface,
     action: input.Action,
     key: input.Key,
     unmapped_key: input.Key,
     mods: input.Mods,
-) !void {
+) !bool {
     const tracy = trace(@src());
     defer tracy.end();
 
@@ -1079,7 +1085,7 @@ pub fn keyCallback(
             self.ignore_char = true;
 
             // No matter what, if there is a binding then we are done.
-            return;
+            return self.ignore_char;
         }
 
         // Handle non-printables
@@ -1172,6 +1178,8 @@ pub fn keyCallback(
             }
         }
     }
+
+    return self.ignore_char;
 }
 
 pub fn focusCallback(self: *Surface, focused: bool) !void {

src/apprt/embedded.zig

@@ -408,17 +408,6 @@ pub const Surface = struct {
         //     mods,
         // });
 
-        // If this is a dead key, then we're composing a character and
-        // we end processing here. We don't process keybinds for dead keys.
-        if (result.composing) {
-            // TODO: we ultimately want to update some surface state so that
-            // we can show the user that we're in dead key mode and the
-            // precomposed character. For now, we can just ignore and that
-            // is not incorrect behavior.
-            log.warn("dead key mode, currently composing", .{});
-            return;
-        }
-
         // We want to get the physical unmapped key to process keybinds.
         const physical_key = keycode: for (input.keycodes.entries) |entry| {
             if (entry.native == keycode) break :keycode entry.key;
@@ -428,7 +417,9 @@ pub const Surface = struct {
         // and attempt to translate it to a key enum and call the key callback.
         // If the length is greater than 1 then we're going to call the
         // charCallback.
-        const key = if (result.text.len == 1) key: {
+        //
+        // We also only do key translation if this is not a dead key.
+        const key = if (!result.composing and result.text.len == 1) key: {
             // A completed key. If the length of the key is one then we can
             // attempt to translate it to a key enum and call the key callback.
             break :key input.Key.fromASCII(result.text[0]) orelse physical_key;
@@ -437,10 +428,32 @@ pub const Surface = struct {
         // If both keys are invalid then we won't call the key callback. But
         // if either one is valid, we want to give it a chance.
         if (key != .invalid or physical_key != .invalid) {
-            self.core_surface.keyCallback(action, key, physical_key, mods) catch |err| {
+            const consumed = self.core_surface.keyCallback(
+                action,
+                key,
+                physical_key,
+                mods,
+            ) catch |err| {
                 log.err("error in key callback err={}", .{err});
                 return;
             };
+
+            // If we consume the key then we want to reset the dead key state.
+            if (consumed) {
+                self.keymap_state = .{};
+                return;
+            }
+        }
+
+        // If this is a dead key, then we're composing a character and
+        // we end processing here. We don't process keybinds for dead keys.
+        if (result.composing) {
+            // TODO: we ultimately want to update some surface state so that
+            // we can show the user that we're in dead key mode and the
+            // precomposed character. For now, we can just ignore and that
+            // is not incorrect behavior.
+            log.warn("dead key mode, currently composing", .{});
+            return;
         }
 
         // Next, we want to call the char callback with each codepoint.

src/apprt/glfw.zig

@@ -740,7 +740,7 @@ pub const Surface = struct {
         // TODO: we need to do mapped keybindings
 
         const core_win = window.getUserPointer(CoreSurface) orelse return;
-        core_win.keyCallback(action, key, key, mods) catch |err| {
+        _ = core_win.keyCallback(action, key, key, mods) catch |err| {
             log.err("error in key callback err={}", .{err});
             return;
         };

src/apprt/gtk.zig

@@ -1167,25 +1167,13 @@ pub const Surface = struct {
         const key = translateKey(keyval);
         const mods = translateMods(state);
         log.debug("key-press code={} key={} mods={}", .{ keycode, key, mods });
-        self.core_surface.keyCallback(.press, key, key, mods) catch |err| {
+        const processed = self.core_surface.keyCallback(.press, key, key, mods) catch |err| {
             log.err("error in key callback err={}", .{err});
             return 0;
         };
 
-        // We generally just say we didn't handle it. We control our
+        // If we processed the key, we say we handled it.
-        // GTK environment so for any keys that matter we'll grab them.
+        return if (processed) 1 else 0;
-        // One of the reasons we say we didn't handle it is so that the
-        // IME can still work.
-        return switch (keyval) {
-            // If the key is tab, we say we handled it because we don't want
-            // tab to move focus from our surface.
-            c.GDK_KEY_Tab => 1,
-            // We do the same for up, because that steals focus from the surface,
-            // in case we have multiple tabs open.
-            c.GDK_KEY_Up => 1,
-
-            else => 0,
-        };
     }
 
     fn gtkKeyReleased(