fcitx service: init

nixos/modules/i18n/inputMethod/fcitx.nix

@@ -0,0 +1,51 @@
+{ config, pkgs, lib, ... }:
+
+with lib;
+
+let
+  cfg = config.i18n.inputMethod.fcitx;
+  fcitxPackage = pkgs.fcitx-with-plugins.override { plugins = cfg.engines; };
+  fcitxEngine = types.package // {
+    name  = "fcitx-engine";
+    check = x: (lib.types.package.check x) && (attrByPath ["meta" "isFcitxEngine"] false x);
+  };
+in
+{
+  options = {
+
+    i18n.inputMethod.fcitx = {
+      enable = mkOption {
+        type    = types.bool;
+        default = false;
+        example = true;
+        description = ''
+          Enable Fcitx input method.
+          Fcitx can be used to input of Chinese, Korean, Japanese and other special characters.
+        '';
+      };
+      engines = mkOption {
+        type    = with types; listOf fcitxEngine;
+        default = [];
+        example = literalExample "with pkgs.fcitx-engines; [ mozc hangul ]";
+        description = ''
+          Enabled Fcitx engines.
+          Available engines can be found by running `nix-env "<nixpkgs>" . -qaP -A fcitx-engines`.
+        '';
+      };
+    };
+
+  };
+
+  config = mkIf cfg.enable {
+    environment.systemPackages = [ fcitxPackage ];
+    gtkPlugins = [ fcitxPackage ];
+    qtPlugins  = [ fcitxPackage pkgs.kde5.fcitx-qt5 ];
+
+    environment.variables = {
+      GTK_IM_MODULE = "fcitx";
+      QT_IM_MODULE  = "fcitx";
+      XMODIFIERS    = "@im=fcitx";
+    };
+    services.xserver.displayManager.sessionCommands = "${fcitxPackage}/bin/fcitx";
+  };
+}