SDL: wayland: Don't enable the text-input protocol when using Fcitx

From 2b375d9704d23dfa72eff1260451050208026413 Mon Sep 17 00:00:00 2001
From: Frank Praznik <[EMAIL REDACTED]>
Date: Sun, 5 Jan 2025 17:53:20 -0500
Subject: [PATCH] wayland: Don't enable the text-input protocol when using
 Fcitx

Otherwise, key repeat will be broken. Enabling it under Wayland isn't recommended anyway.
---
 src/video/wayland/SDL_waylandevents.c   | 19 ++++++++++++++++++-
 src/video/wayland/SDL_waylandevents_c.h |  3 ++-
 src/video/wayland/SDL_waylandvideo.c    |  3 +--
 3 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/src/video/wayland/SDL_waylandevents.c b/src/video/wayland/SDL_waylandevents.c
index 842dcf6f8a701..6784bf0803995 100644
--- a/src/video/wayland/SDL_waylandevents.c
+++ b/src/video/wayland/SDL_waylandevents.c
@@ -2669,7 +2669,7 @@ void Wayland_create_primary_selection_device(SDL_VideoData *d)
     }
 }
 
-void Wayland_create_text_input(SDL_VideoData *d)
+static void Wayland_create_text_input(SDL_VideoData *d)
 {
     SDL_WaylandTextInput *text_input = NULL;
 
@@ -2696,6 +2696,23 @@ void Wayland_create_text_input(SDL_VideoData *d)
     }
 }
 
+void Wayland_create_text_input_manager(SDL_VideoData *d, uint32_t id)
+{
+#ifdef HAVE_FCITX
+    const char *im_module = SDL_getenv("SDL_IM_MODULE");
+    if (im_module && SDL_strcmp(im_module, "fcitx") == 0) {
+        /* Override the Wayland text-input protocol when Fcitx is enabled, like how GTK_IM_MODULE does.
+         *
+         * The Fcitx wiki discourages enabling it under Wayland via SDL_IM_MODULE, so its presence must
+         * be intentional, and this workaround is needed for fixing key repeat detection.
+         */
+        return;
+    }
+#endif
+
+    d->text_input_manager = wl_registry_bind(d->registry, id, &zwp_text_input_manager_v3_interface, 1);
+    Wayland_create_text_input(d);
+}
 
 // Pen/Tablet support...
 
diff --git a/src/video/wayland/SDL_waylandevents_c.h b/src/video/wayland/SDL_waylandevents_c.h
index 069a0d96379fb..5073472da4e53 100644
--- a/src/video/wayland/SDL_waylandevents_c.h
+++ b/src/video/wayland/SDL_waylandevents_c.h
@@ -157,7 +157,8 @@ extern int Wayland_WaitEventTimeout(SDL_VideoDevice *_this, Sint64 timeoutNS);
 
 extern void Wayland_create_data_device(SDL_VideoData *d);
 extern void Wayland_create_primary_selection_device(SDL_VideoData *d);
-extern void Wayland_create_text_input(SDL_VideoData *d);
+
+extern void Wayland_create_text_input_manager(SDL_VideoData *d, uint32_t id);
 
 extern void Wayland_input_initialize_seat(SDL_VideoData *d);
 extern void Wayland_display_destroy_input(SDL_VideoData *d);
diff --git a/src/video/wayland/SDL_waylandvideo.c b/src/video/wayland/SDL_waylandvideo.c
index a69b70f6932a2..7ea5a582f5a1b 100644
--- a/src/video/wayland/SDL_waylandvideo.c
+++ b/src/video/wayland/SDL_waylandvideo.c
@@ -1234,8 +1234,7 @@ static void display_handle_global(void *data, struct wl_registry *registry, uint
     } else if (SDL_strcmp(interface, "xdg_activation_v1") == 0) {
         d->activation_manager = wl_registry_bind(d->registry, id, &xdg_activation_v1_interface, 1);
     } else if (SDL_strcmp(interface, "zwp_text_input_manager_v3") == 0) {
-        d->text_input_manager = wl_registry_bind(d->registry, id, &zwp_text_input_manager_v3_interface, 1);
-        Wayland_create_text_input(d);
+        Wayland_create_text_input_manager(d, id);
     } else if (SDL_strcmp(interface, "wl_data_device_manager") == 0) {
         d->data_device_manager = wl_registry_bind(d->registry, id, &wl_data_device_manager_interface, SDL_min(3, version));
         Wayland_create_data_device(d);