profiles/i18n: modularize common config into separate options

modules/nixos/profiles/i18n.nix

@@ -3,13 +3,27 @@
 
 let
   cfg = config.profiles.i18n;
-in {
+in
-  options.profiles.i18n.enable = lib.mkEnableOption "i18n-related options";
+{
+  options.profiles.i18n = {
+    enable = lib.mkEnableOption "i18n-related options";
+    ibus.enable = lib.mkEnableOption "i18n config with ibus";
+    fcitx5.enable = lib.mkEnableOption "i18n config with fcitx5";
+  };
+
+  config = lib.mkIf cfg.enable (lib.mkMerge [
+    {
+      assertions = let enabledi18nConfigs = lib.countAttrs (_: setup: lib.isAttrs setup && setup.enable) cfg; in
+        [{
+          assertion = enabledi18nConfigs < 1;
+          message = ''
+            Only one i18n setup should be enabled at any given time.
+          '';
+        }];
 
-  config = lib.mkIf cfg.enable {
       # I don't speak all of the listed languages. It's just nice to have some
       # additional language packs for it. ;p
-    i18n.supportedLocales = [
+      i18n.supportedLocales = lib.mkBefore [
         "en_US.UTF-8/UTF-8"
         "ja_JP.UTF-8/UTF-8"
         "ko_KR.UTF-8/UTF-8"
@@ -39,5 +53,38 @@ in {
         source-han-serif
         source-han-mono
       ];
+    }
+
+    (lib.mkIf cfg.ibus.enable {
+      i18n.inputMethod = {
+        enabled = "ibus";
+        ibus.engines = with pkgs.ibus-engines; [
+          mozc
+          rime
+          hangul
+          table
+          table-others
+          typing-booster
+          uniemoji
+        ];
       };
+    })
+
+    (lib.mkIf cfg.fcitx5.enable {
+      i18n.inputMethod = {
+        enabled = "fcitx5";
+        fcitx5 = {
+          enableRimeData = true;
+          addons = with pkgs; [
+            fcitx5-lua
+            fcitx5-mozc
+            fcitx5-rime
+            fcitx5-table-extra
+            fcitx5-table-other
+            fcitx5-unikey
+          ];
+        };
+      };
+    })
+  ]);
 }

modules/nixos/workflows/a-happy-gnome/default.nix

@@ -110,18 +110,9 @@ in
     };
 
     services.packagekit.enable = false;
-
+    profiles.i18n = {
-    i18n.inputMethod = {
+      enable = true;
-      enabled = "ibus";
+      ibus.enable = true;
-      ibus.engines = with pkgs.ibus-engines; [
-        mozc
-        rime
-        hangul
-        table
-        table-others
-        typing-booster
-        uniemoji
-      ];
     };
 
     # Since we're using KDE Connect, we'll have to use gsconnect.