Bash script for update/install Mozilla Firefox on Debian

firefox_update.sh

#!/usr/bin/env bash
# TAGS
#   firefox_update.sh V-4.3
#   https://gist.github.com/ngadmini/522f482baacece8dfca570a113b28102
# AUTHOR
#   ngadimin@warnet-ersa.net
# TL;DR
#   install (system-wide installation) OR update to latest version of Mozilla Firefox
#   suggestion NOPASSWD for sudo:
#      echo "$USER ALL=(ALL:ALL) NOPASSWD: ALL" | sudo tee -a /etc/sudoers
# pgrep firefox | xargs kill
set -e
PATH=/usr/local/bin:/usr/bin:/bin:${PATH}
_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
_exec=/usr/bin/firefox-bin
_path=/opt/firefox
_app=/usr/share/applications/Firefox.desktop
_tar=firefox.tar.bz2
:<<'comment'
_uri0="https://download.mozilla.org/?product=firefox-nightly-latest&os=linux64&lang=en-US"
_uri0="https://download.mozilla.org/?product=firefox-beta-latest&os=linux64&lang=en-US"
_uri0="https://download.mozilla.org/?product=firefox-devedition-latest&os=linux64&lang=en-US"
_uri0="https://download.mozilla.org/?product=firefox-esr-latest&os=linux64&lang=en-US"
_uri0="https://download.mozilla.org/?product=firefox-latest&os=linux64&lang=en-US"
comment
_uri0="https://download.mozilla.org/?product=firefox-latest&os=linux64&lang=en-US"
_uri1="https://raw.githubusercontent.com/mozilla/sumo-kb/main/install-firefox-linux/firefox.desktop"
_new=$(curl -sfI "${_uri0}" | sed -n 's/.*firefox-\(.*\)\.tar.*/\1/p')

f_curl() {
   if command -v curl >> /dev/null 2>&1; then
      true
   else
      printf "[FAIL] curl not installed\n"
      read -r -p "[CONFIRM] do you want to install curl ? [Y/n] " confirm
      case ${confirm:0:1} in
         y|Y|"") printf "[INFO] installing curl ..."
                 sudo apt install curl -y -qq >> /dev/null 2>&1;;
              *) printf "exiting\n"; return 1;;
      esac
   fi
}

f_stat() {
   [[ -h ${_exec} ]] || sudo ln -sf "${_path}"/firefox "${_exec}"
   for _X in {"$_path","$_path"/firefox}; do
      if [[ $(stat -c "%a" "${_X}") != 755 ]]; then sudo chhmod 755 "${_X}"; fi
   done
}

f_fail() { printf "[FAIL] download fail\n"; return 1; }

f_update() {
   printf "[INFO] download latest version: Firefox %s\n" "${_new}"
   curl -sL -o "${_tar}" "${_uri0}" || f_fail
   printf "[INFO] removing old version\n"
   sudo rm -rf ${_path}-*
   sudo mv "${_path}" "${_path}-${_cur}"
   printf "[INFO] applying latest version: Firefox %s\n" "${_new}"
   sudo tar -xjf "${_tar}" -C /opt
   find "${_DIR}" -type f -name "${_tar}" -print0 | xargs -r0 rm -rf
   f_stat
   printf "[DONE] bye!\n\n"
}

f_install() {
   # check required library glibc
   if ! dpkg -s "libdbus-glib-1-2" >> /dev/null 2>&1; then
      sudo apt install libdbus-glib-1-2 -y -qq >> /dev/null 2>&1
   fi

   printf "[INFO] download latest version: Firefox %s\n" "${_new}"
   curl -sL -o "${_tar}" "${_uri0}" || f_fail
   printf "[INFO] applying latest version: Firefox %s\n" "${_new}"
   sudo tar -xjf "${_tar}" -C /opt
   find "${_DIR}" -type f -name "${_tar}" -print0 | xargs -r0 rm -rf
   curl -s -o "${_app}" "${_uri1}" || f_fail
   f_stat
   printf "[DONE] bye!\n\n"
}

f_confirm() {
   read -r -p "do you want to closed it's ? [Y/n] " answer
   case ${answer:0:1} in
      y|Y:"")  printf "[INFO] closing and updating Firefox\n"
               kill -9 "$(pgrep ${_exec##*/})"
               f_update;;
           *)  printf "\n"; return 1;;
   esac
}

f_check() {
   _cur=$(firefox -v | awk -F' ' '{print $NF}')
   if ! [[ ${_new} == "${_cur}" ]]; then
      printf "[INFO] you're running release-version: Firefox %s\n" "${_cur}"
      printf "[INFO] an update available: Firefox %s\n" "${_new}"
      if pgrep -x "${_exec##*/})" &>/dev/null; then
         f_update
      else
         printf "[FAIL] %s is running (proc_id: %s)\n" "${_exec##*/}" "$(pgrep ${_exec##*/})"
         printf "[HINT] closed it's, then run %s again\n" "${0##*/}"
         f_confirm   # append option to close running firefox, then update it's
      fi
   else
      printf "[INFO] no update available\nyou're running latest release-version: Firefox %s\n\n" "${_new}"
      return 1
   fi
}

#   main script
cd "${_DIR}"
printf "\n[INFO] starting %s ...\n" "${0##*/}"
f_curl

if command -v firefox >> /dev/null 2>&1; then
   f_check
else
   printf "[INFO] look like firefox not installed\n"
   # append option to install it's
   read -r -p "do you want to install it's ? [Y/n] " answer
   case ${answer:0:1} in
      y|Y|"") f_install;;
           *) printf "\n"; exit 1;;
   esac
fi

exit 0

direct usage:

curl -sL https://gist.github.com/ngadmini/522f482baacece8dfca570a113b28102/raw | bash
wget -qO- https://gist.github.com/ngadmini/522f482baacece8dfca570a113b28102/raw | bash