How to interact with non-English language input with Helix?

[noisetide]

When using Helix I want to type in a different language other that English in Input mode. To do that I switch the input language layout in fcitx5 (for example to Ukrainian) and type normally, but as soon as exit the insert mode with esc keybind and I try to perform any action that requires English letter to be inputted for (example i keybind to go back into Insert mode or h, j, k, l movement) in Normal mode input does not get through as Helix does not recognize the non-English input. (When instead of i the terminal gets Cyrillic letter ш, instead of h, j, k, l it gets Cyrillic letters р, о, л, д etc. )

How do I configure and fix this issue and have the other language input layout act only when in Insert mode, so I don't have to switch each time back to English to perform any actions in Normal mode?

I'm using Kitty Terminal.

Help would be very appreciated. 🙏

[Jackson-Nickk]

I don't know why there's no other discussion about this and no one commented on this issues. This is a very important subject for a multi purpose text editor.

[xubaiwang]

@rotteegher @Jackson-Nickk

Doesn't fcitx5 have a default keybinding Ctrl+Shift to switch between input methods?
Or if you want helix to automatically switch to English when in normal mode?

For the second case, you can try rebinding the keys for mode switching to also changing the fcitx5 state using fcitx5-remote cli tool.

[keys.normal]
i = [
  # switch to insert mode
  "insert_mode",
  # activate input method (throught shell command)
  # this line is not necessary in case you still want to input English in insert mode
  ":sh fcitx5-remote -o",
  # logging (testing only, should be removed)
  ":sh echo 'to insert mode' >> log.txt"
]
# `I`, `a`, `A`, `o` and `O` are similar.
# You can find the default keymaps at https://docs.helix-editor.com/keymap.html#changes

[keys.insert]
esc = [
  # switch back to normal mode
  "normal_mode",
  # inactivate input method
  ":sh fcitx5-remote -o",
  # logging (should be removed)
  ":sh echo 'to normal mode' >> log.txt"
]

I'm not sure whether the fcitx5-remote command call is correct here, as I no longer use it.
But you can definitely get the idea. And you can find more details about this command using fcitx5-remote --help.

[noisetide]

Thanks for the answer finally!
It's a great workaround, but I implemented something that worked (partially) without switching languages constantly. (even automatically)

The problem in itself is that I have to switch the language anytime I want to perform any vim-like function, apart from just typing text in input mode. Constantly switching gets just too annoying, so I implemented this monster in my nix config of helix editor to rebind some Cyrillic letters into their respective Latin letters equivalent position on the keyboard and their functions in Helix like this:

{
  config,
  lib,
  pkgs,
  ...
}:
let
  tex = (pkgs.texlive.combine {
    inherit (pkgs.texlive) scheme-full
      dvisvgm dvipng # for preview and export as html
      wrapfig amsmath ulem hyperref capt-of tex-gyre cyrillic;
      # (setq org-latex-compiler "lualatex")
      # (setq org-preview-latex-default-process 'dvisvgm)
  });
in
{
  config = lib.mkIf config.custom.helix.enable {
    home.packages = [
      pkgs.lldb
      pkgs.clang-tools
      tex
      # pkgs.texlive.combined.scheme-full
      pkgs.texlivePackages.cyrillic
      pkgs.texlivePackages.tex-gyre
      pkgs.texlab
      pkgs.pandoc
      pkgs.yamlfmt
      pkgs.yaml-language-server
    ];
    programs.helix = {
      enable = true;
      defaultEditor = config.custom.shell.defaultEditor == "hx";
      themes = {
        mtr = {
          # "inherits" = "heisenberg";
          # "inherits" = "curzon";
          # "inherits" = "mellow";
          "inherits" = "ferra";
          # "inherits" = "vim_dark_high_contrast";
          # "inherits" = "catppuccin_mocha";
          # "inherits" = "catppuccin_latte";
          "ui.background" = {
            fg = "none";
          };
        };
      };
      languages = {
        language = [
          {
            name = "yaml";
            formatter = { command = "${pkgs.yamlfmt}/bin/yamlfmt"; args = [ "-in" ];};
            language-servers = [ "yaml-language-server" ];
          }
        ];
        language-server.yaml-language-server.command = "${pkgs.yaml-language-server}/bin/yaml-language-server";
        language-server.rust-analyzer.command = "${pkgs.rust-analyzer}/bin/rust-analyzer";
        language-server.rust-analyzer.config = {
          procMacro = {
            ignored = {
              # leptos_macro = [ "server" "component" ]; // makes huge red warning...
            };
          };
          diagnostics.disabled = [
            "inactive-code"
            "unlinked-file"
          ];
        };
      };
      settings = {
        theme = "mtr";
        editor = {
          lsp.display-messages = true;
          lsp.display-inlay-hints = true;
          statusline = {
            center = [ "file-absolute-path" ];
          };
          true-color = true;
          line-number = "relative";
          mouse = true;
          rulers = [ 200 ];
          bufferline = "always";
        };
        keys.select = {
          X = [
            "extend_line_up"
            "extend_to_line_bounds"
          ];
          "Ч" = [
            "extend_line_up"
            "extend_to_line_bounds"
          ];
          A-x = "extend_to_line_bounds";
          "A-ч" = [
            "extend_to_line_bounds"
          ];
          C-y = "yank_to_clipboard";
          "C-н" = "yank_to_clipboard";
        };
        keys.normal = {
          # until fixed ISSUE: https://github.com/helix-editor/helix/issues/10389
          # Workaround for ukrainian lagnuage key remap
          # українська мапа клавіатури:

          # перший ряд
          "й" = [ "replay_macro" ]; # q
          "ц" = [ "move_next_word_start" ]; # w
          "у" = [ "move_next_word_end" ]; # e
          "к" = [ "replace" ]; # r
          "е" = [ "find_till_char" ]; # t
          "н" = [ "yank_to_clipboard" ]; # y
          "г" = [ "undo" ]; "C-г" = [ "page_cursor_half_up" ]; # u
          "ш" = [ "insert_mode" ]; "C-ш" = [ "jump_forward" ]; # i
          "щ" = [ "open_below" ]; "C-щ" = [ "jump_backward" ]; # o
          "з" = [ "paste_clipboard_after" ]; # p
          "х" = [ ]; # @
          "ї" = [ ]; # [

          "Й" = [ "record_macro" ]; # Q
          "Ц" = [ "move_next_long_word_start" ]; # W
          "У" = [ ]; # E
          "К" = [ "replace_selections_with_clipboard" ]; # R
          "Е" = [ "till_prev_char" ]; # T
          "Н" = [ "yank_main_selection_to_clipboard" ]; # Y
          "Г" = [ "redo" ]; # U
          "Ш" = [ "insert_at_line_start" ]; # I
          "Щ" = [ "open_above" ]; # O
          "З" = [ "paste_clipboard_before" ]; # P
          # "Х" = [ ]; # `
          # "Ї" = [ ]; # {

          # другий ряд 
          "ф" = [ "append_mode" ]; # a
          "і" = [ "select_regex" ]; "C-і" = [ "save_selection" ]; "A-і" = [ "split_selection_on_newline" ]; # s
          "в" = [ "delete_selection" ]; "C-в" = [ "page_cursor_half_down" ]; # d
          "а" = [ "find_next_char" ]; "C-а" = [ "page_down" ]; # f
          "п" = [ ]; # g
          "р" = [ "move_char_left" ]; # h
          "о" = [ "move_visual_line_down" ]; # j
          "л" = [ "move_visual_line_up" ]; # k
          "д" = [ "move_char_right" ]; # l
          # "ж" = [ ]; # ;
          # "є" = [ ]; # : # important to leave unbinded to not confuse layouts
          # "ґ" = [ ]; # ]

          "Ф" = [ "insert_at_line_end" ]; # A
          "І" = [ "split_selection" ]; # S
          # "В" = [ ]; # D
          "А" = [ "find_prev_char" ]; # F
          "П" = [ "goto_line" ]; # G
          # "Р" = [ ]; # H
          "О" = [ "join_selections" ]; # J
          "Л" = [ "keep_selections" ]; # K
          # "Д" = [ ]; # L
          # "Ж" = [ ]; # +
          # "Є" = [ ]; # *
          # "Ґ" = [ ]; # }

          # третій ряд
          # "я" = [ ]; # z
          "ч" = [ "extend_line_below" ]; # x
          "с" = [ "change_selection" ]; "A-с" = [ "change_selection_noyank" ]; # c
          "м" = [ "select_mode" ]; # v
          "и" = [ "move_prev_word_start" ]; "C-и" = [ "page_up" ]; # b
          "т" = [ "search_next" ]; # n
          "ь" = [ ]; # m
          "б" = [ ]; # ,
          "ю" = [ ]; # .
          "." = [ "global_search" ]; # /

          # "Я" = [ ]; # Z
          "Ч" = [ "extend_to_line_bounds" ]; # X
          "С" = [ ]; # "М" = []; # V
          "И" = [ "move_prev_long_word_start" ]; # B
          "Т" = [ "search_prev" ]; # N
          "Ь" = [ ]; # M
          "Б" = [ ]; # <
          "Ю" = [ ]; # >
          "," = [ ]; # ?

          X = [
            "extend_line_up"
            "extend_to_line_bounds"
          ];
          A-x = "extend_to_line_bounds";
          C-p = [
            "move_line_up"
            "scroll_up"
          ];
          C-n = [
            "move_line_down"
            "scroll_down"
          ];
          C-y = "yank_to_clipboard";
          esc = [
            "collapse_selection"
            "keep_primary_selection"
          ]; # FIXME
        };
        editor.cursor-shape = {
          insert = "bar";
          # normal = "block";
          select = "underline";
        };
        editor.file-picker = {
          hidden = false;
        };
      };
    };
  };
}

Or also here's how actual helix config file looks like:

theme = "mtr"
[editor]
bufferline = "always"
line-number = "relative"
mouse = true
rulers = [200]
true-color = true

[editor.cursor-shape]
insert = "bar"
select = "underline"

[editor.file-picker]
hidden = false

[editor.lsp]
display-inlay-hints = true
display-messages = true

[editor.statusline]
center = ["file-absolute-path"]

[keys.normal]
"," = []
"." = ["global_search"]
A-x = "extend_to_line_bounds"
"A-с" = ["change_selection_noyank"]
"A-і" = ["split_selection_on_newline"]
C-n = ["move_line_down", "scroll_down"]
C-p = ["move_line_up", "scroll_up"]
C-y = "yank_to_clipboard"
"C-а" = ["page_down"]
"C-в" = ["page_cursor_half_down"]
"C-г" = ["page_cursor_half_up"]
"C-и" = ["page_up"]
"C-ш" = ["jump_forward"]
"C-щ" = ["jump_backward"]
"C-і" = ["save_selection"]
X = ["extend_line_up", "extend_to_line_bounds"]
esc = ["collapse_selection", "keep_primary_selection"]
"І" = ["split_selection"]
"А" = ["find_prev_char"]
"Б" = []
"Г" = ["redo"]
"Е" = ["till_prev_char"]
"З" = ["paste_clipboard_before"]
"И" = ["move_prev_long_word_start"]
"Й" = ["record_macro"]
"К" = ["replace_selections_with_clipboard"]
"Л" = ["keep_selections"]
"Н" = ["yank_main_selection_to_clipboard"]
"О" = ["join_selections"]
"П" = ["goto_line"]
"С" = []
"Т" = ["search_prev"]
"У" = []
"Ф" = ["insert_at_line_end"]
"Ц" = ["move_next_long_word_start"]
"Ч" = ["extend_to_line_bounds"]
"Ш" = ["insert_at_line_start"]
"Щ" = ["open_above"]
"Ь" = []
"Ю" = []
"а" = ["find_next_char"]
"б" = []
"в" = ["delete_selection"]
"г" = ["undo"]
"д" = ["move_char_right"]
"е" = ["find_till_char"]
"з" = ["paste_clipboard_after"]
"и" = ["move_prev_word_start"]
"й" = ["replay_macro"]
"к" = ["replace"]
"л" = ["move_visual_line_up"]
"м" = ["select_mode"]
"н" = ["yank_to_clipboard"]
"о" = ["move_visual_line_down"]
"п" = []
"р" = ["move_char_left"]
"с" = ["change_selection"]
"т" = ["search_next"]
"у" = ["move_next_word_end"]
"ф" = ["append_mode"]
"х" = []
"ц" = ["move_next_word_start"]
"ч" = ["extend_line_below"]
"ш" = ["insert_mode"]
"щ" = ["open_below"]
"ь" = []
"ю" = []
"і" = ["select_regex"]
"ї" = []

[keys.select]
A-x = "extend_to_line_bounds"
"A-ч" = ["extend_to_line_bounds"]
C-y = "yank_to_clipboard"
"C-н" = "yank_to_clipboard"
X = ["extend_line_up", "extend_to_line_bounds"]
"Ч" = ["extend_line_up", "extend_to_line_bounds"]

[noisetide]

Also there is this one I forgot to mention: #10389

[Jackson-Nickk]

I think this should be a bug report instead of a question.

[noisetide]

I did a bit of research on this topic.

vim and nvim also have the same problem, and even many other TUI programs.
My guess is that it's more of a foundational problem of how the input of characters is handled by the terminal emulator and how inputted characters are handled/treated by the program itself.

What the actual program like helix, nvim, vim or even something like htop receives, are actual characters, not the low level raw keyboard input key presses themselves.
Like the key-code of the key sent by the keyboard hardware to the OS is different from the char that is received by the program.

For example:
When the key k is pressed, the keyboard sends a key-code to the OS on the hardware level, then this OS processes it with an input engine like fcitx5 or built in layout, only after that, the input engine sends a character to the terminal emulator, then after all of that a TUI program like helix receives a character from the terminal input processor. If that character sent by the input engine is still k (in case of Latin alphabet input mode, regardless of the language), then terminal emulator sends a signal to the program as k has been pressed to the program and performs an action mapped specifically to k, but if the input mode is different, that has different from Latin alphabet characters (for example Ukrainian, which has Cyrillic), a different character л is received by the terminal instead, so the TUI program doesn't recognize it, and doesn't do anything, as nothing is mapped to that specific character л.

What I did here in the helix's configuration above is just added what to do when those unknown characters are received by the program.
When Cyrillic characters are received, a mapped functions, same to the relative position of actual Latin characters on the keyboard are performed in the program.

I'm not sure if it is even possible to securely get low level access to the keyboard hardware, or solve the problem some other way from helix itself, apart from defining key-maps for alphabets, which is very crude and doesn't solve the underlying problem, and wouldn't even work with other languages and alphabets if they don't have Latin characters.

Technically you can even do something like this:

"聡" = ["insert_mode"]

And that will work if that character is received by the terminal from the input engine.
This applies to any character supported by the input encoding like UTF-8 for example.

It's more of an input engine problem, than a problem from the helix or any other TUI program's side.

The proposed by the @xubaiwang solution, works as a good workaround, whenever not in input mode you automatically switch input engine like fcitx5 to a Latin alphabet which works for all commands, which was intended to be used.

I'll mark that as an answer then, as this issue is not even a bug. 👍