#!/bin/bash

# omarchy:summary=Show or switch the system language between English and Simplified Chinese
# omarchy:args=[en|zh]
# omarchy:examples=omarchy language | omarchy language zh
# omarchy:requires-sudo=true

set -euo pipefail

locale_conf=/etc/locale.conf

if (($# == 0)); then
  lang=$(sed -n 's/^LANG=//p' "$locale_conf")
  # locale.conf may quote the value.
  lang=${lang#[\"\']}
  printf '%s\n' "${lang%[\"\']}"
  exit 0
fi

case ${1:-} in
en) lang=en_US.UTF-8 ;;
zh) lang=zh_CN.UTF-8 ;;
*)
  echo "Usage: omarchy-language [en|zh]" >&2
  exit 1
  ;;
esac

sudo sed -i "s/^#\(${lang/./\\.} UTF-8\)/\1/" /etc/locale.gen
sudo locale-gen
if grep -q '^LANG=' "$locale_conf"; then
  sudo sed -i "s/^LANG=.*/LANG=$lang/" "$locale_conf"
else
  sudo sed -i '$a\' "$locale_conf"
  echo "LANG=$lang" | sudo tee -a "$locale_conf" >/dev/null
fi

# The language reaches only a new session, so offer one in the new language.
prompt=$(LANG=$lang omarchy-text "Log out now to switch the language?")
log_out=$(LANG=$lang omarchy-text "Log out now")
later=$(LANG=$lang omarchy-text "Later")
if [[ -t 0 && -t 1 ]] && gum confirm --affirmative "$log_out" --negative "$later" "$prompt" 2>&1; then
  omarchy-system-logout
else
  LANG=$lang omarchy-text "Log back in to switch the language."
fi