#!/bin/bash

readonly ROOT_UID=0
readonly MAX_DELAY=20 # max delay for user to enter root password

REPO_DIR="$(cd "$(dirname "$0")" && pwd)"
BACKGROUND_DIR="/usr/share/backgrounds"
PROPERTIES_DIR="/usr/share/gnome-background-properties"

THEME_VARIANTS=('WhiteSur' 'Monterey')

#COLORS
CDEF=" \033[0m"                               # default color
CCIN=" \033[0;36m"                            # info color
CGSC=" \033[0;32m"                            # success color
CRER=" \033[0;31m"                            # error color
CWAR=" \033[0;33m"                            # waring color
b_CDEF=" \033[1;37m"                          # bold default color
b_CCIN=" \033[1;36m"                          # bold info color
b_CGSC=" \033[1;32m"                          # bold success color
b_CRER=" \033[1;31m"                          # bold error color
b_CWAR=" \033[1;33m"                          # bold warning color

# echo like ...  with  flag type  and display message  colors
prompt () {
  case ${1} in
    "-s"|"--success")
      echo -e "${b_CGSC}${@/-s/}${CDEF}";;    # print success message
    "-e"|"--error")
      echo -e "${b_CRER}${@/-e/}${CDEF}";;    # print error message
    "-w"|"--warning")
      echo -e "${b_CWAR}${@/-w/}${CDEF}";;    # print warning message
    "-i"|"--info")
      echo -e "${b_CCIN}${@/-i/}${CDEF}";;    # print info message
    *)
    echo -e "$@"
    ;;
  esac
}

install() {
  local theme="$1"
  prompt -i "\n * Install ${theme} in ${BACKGROUND_DIR}... "
  [[ -d ${BACKGROUND_DIR}/${theme} ]] && rm -rf ${BACKGROUND_DIR}/${theme}
  [[ -f ${PROPERTIES_DIR}/${theme}.xml ]] && rm -rf ${PROPERTIES_DIR}/${theme}.xml
  cp -r ${REPO_DIR}/${theme} ${BACKGROUND_DIR}
  cp -r ${REPO_DIR}/gnome-background-properties/${theme}.xml ${PROPERTIES_DIR}
}

uninstall() {
  local theme="$1"
  prompt -i "\n * Uninstall ${theme}... "
  [[ -d ${BACKGROUND_DIR}/${theme} ]] && rm -rf ${BACKGROUND_DIR}/${theme}
  [[ -f ${PROPERTIES_DIR}/${theme}.xml ]] && rm -rf ${PROPERTIES_DIR}/${theme}.xml
}

while [[ $# -gt 0 ]]; do
  case "${1}" in
    -u|--uninstall)
      uninstall='true'
      shift
      ;;
    -t|--theme)
      shift
      for variant in "$@"; do
        case "$variant" in
          WhiteSur)
            themes+=("${THEME_VARIANTS[0]}")
            shift
            ;;
          Monterey)
            themes+=("${THEME_VARIANTS[1]}")
            shift
            ;;
          -*)
            break
            ;;
          *)
            echo "ERROR: Unrecognized color variant '$1'."
            echo "Try '$0 --help' for more information."
            exit 1
            ;;
        esac
      done
      ;;
    -h|--help)
      usage
      exit 0
      ;;
    *)
      prompt -e "ERROR: Unrecognized installation option '$1'."
      prompt -i "Try '$0 --help' for more information."
      exit 1
      ;;
  esac
done

themes=("${THEME_VARIANTS[@]}")

install_wallpaper() {
  for theme in "${themes[@]}"; do
    install "$theme"
  done
}

uninstall_wallpaper() {
  for theme in "${themes[@]}"; do
    uninstall "$theme"
  done
}

sudo_access() {
  # Error message
  prompt -e "\n [ Error! ] -> Run me as root ! "

  # persisted execution of the script as root
  read -p "[ Trusted ] Specify the root password : " -t${MAX_DELAY} -s
  [[ -n "$REPLY" ]] && {
    sudo -S <<< $REPLY $0
  } || {
    clear
    prompt -i "\n Operation canceled by user, Bye!"
    exit 1
  }
}

if [[ "$UID" -eq "$ROOT_UID" ]] && [[ "${uninstall}" != 'true' ]]; then
  prompt -s ""; install_wallpaper
  prompt -s "\n * All done!"
  prompt -s ""
else
  [[ "${uninstall}" != 'true' ]] && sudo_access
fi

if [[ "$UID" -eq "$ROOT_UID" ]] && [[ "${uninstall}" == 'true' ]]; then
  prompt -s ""; uninstall_wallpaper
  prompt -s "\n * All done!"
  prompt -s ""
else
  prompt -i "\n Run this with sudo, try it again!"
  exit 1
fi