fix, check session's keyboard mode on conn

Signed-off-by: fufesou <shuanglongchen@yeah.net>

flutter/lib/models/model.dart

@@ -703,6 +703,10 @@ class FfiModel with ChangeNotifier {
     _pi.isSet.value = true;
     stateGlobal.resetLastResolutionGroupValues(peerId);
 
+    if (isDesktop) {
+      checkDesktopKeyboardMode();
+    }
+
     notifyListeners();
 
     if (!isCache) {
@@ -710,6 +714,36 @@ class FfiModel with ChangeNotifier {
     }
   }
 
+  checkDesktopKeyboardMode() async {
+    final curMode = await bind.sessionGetKeyboardMode(sessionId: sessionId);
+    if (curMode != null) {
+      if (bind.sessionIsKeyboardModeSupported(
+          sessionId: sessionId, mode: curMode)) {
+        return;
+      }
+    }
+
+    // If current keyboard mode is not supported, change to another one.
+
+    if (stateGlobal.grabKeyboard) {
+      for (final mode in [kKeyMapMode, kKeyLegacyMode]) {
+        if (bind.sessionIsKeyboardModeSupported(
+            sessionId: sessionId, mode: mode)) {
+          bind.sessionSetKeyboardMode(sessionId: sessionId, value: mode);
+          break;
+        }
+      }
+    } else {
+      for (final mode in [kKeyMapMode, kKeyTranslateMode, kKeyLegacyMode]) {
+        if (bind.sessionIsKeyboardModeSupported(
+            sessionId: sessionId, mode: mode)) {
+          bind.sessionSetKeyboardMode(sessionId: sessionId, value: mode);
+          break;
+        }
+      }
+    }
+  }
+
   tryUseAllMyDisplaysForTheRemoteSession(String peerId) async {
     if (bind.sessionGetUseAllMyDisplaysForTheRemoteSession(
             sessionId: sessionId) !=