dotfiles/styler/.local/bin/styler

#!/usr/bin/env bash

readonly BASE_PATH="${STYLER_DATA_PATH:-${XDG_DATA_HOME:-$HOME/.local/share}/styler}"

readonly PACKAGE_PATH="$BASE_PATH/packages"
readonly PROCESSOR_PATH="$BASE_PATH/processors"

main() {
  local cmd=""
  local ret=0

  case "$1" in
  -s | --set | set)
    cmd="set_theme"
    ;;
  -l | --list | list)
    cmd="list"
    ;;
  -v | --version | version)
    printf "Program theming script.\n\n©Marty Oehme\n\nVersion: 0.1.0\n"
    exit 0
    ;;
  -h | --help | help | *)
    cmd="usage"
    ;;
  esac
  shift

  $cmd "$1"
  ret=$((ret + $?))
  exit $ret
}

usage() {
  printf "%s\n" \
    "" \
    " styler -      Quickly switch your linux style." \
    "               Uses base16 themes to quickly set them for a variety of applications." \
    "" \
    " Usage: styler [-hv | set base16-themename]" \
    "" \
    " Options:" \
    "" \
    "     -s | set        Set the theme. Use any valid base16 theme name (without base16- prefix)." \
    "" \
    "     -h | help       Print out this help." \
    "" \
    "     -v | version    Print out program information." \
    "" \
    ""
}

# retrieves all relevant packages from BASE_PATH/packages
# 'relevant' here means they follow github pattern of author/repository
get_packages() {
  for author in "$PACKAGE_PATH"/*; do
    # TODO should eventually be used to either distinguish between author/pkg and pkg packages
    # or to spit out a warning if they should not be used.
    # if grep -q -e '^base16-' <<<"$(basename -- "$author")"; then
    #   echo ERROR
    # fi
    for package in "$author"/*; do
      [[ -e "$author" ]] || break
      [[ -d "$package" ]] || break
      printf "%s/%s\n" "$(basename -- "$author")" "$(basename -- "$package")"
    done
  done
}

# retrieves all processors from BASE_PATH/processors
# 'relevant' here means they follow github pattern of author/repository
get_processors() {
  for processor in "$PROCESSOR_PATH"/*; do
    [[ -e "$processor" ]] || break
    [[ -f "$processor" ]] || break
    printf "%s\n" "$(basename -- "$processor")"
  done
}

# retrieves all installed themes from all packages, appends applications they exist for
get_themes() {
  local themes
  themes=$(find "$PACKAGE_PATH" -type f -name 'base16-*')
  echo "$themes" | sed "s/.*\\/base16-//" | sed "s/\\..*//" | sort | uniq
}

set_theme() {
  local theme="$1"

  local packages
  packages="$(get_packages)"
  if [[ -z "$packages" ]]; then
    printf "ERROR: No base16 packages installed. Please install at least 1 base16 package in %s/.\n" "$PACKAGE_PATH" >&2
    exit 1
  fi

  local processors
  processors="$(get_processors)"
  if [[ -z "$processors" ]]; then
    printf "ERROR: No application processors installed. Please install at least one processor in %s/.\n" "$PROCESSOR_PATH" >&2
    exit 1
  fi

  for pkg in $packages; do
    local appext

    # filter the application a package targets, since base16 packages
    # carry standard names this removes everything before base16-
    # the result is the application it targets
    # shellcheck disable=SC2001
    appext=$(sed "s|^[[:alnum:]]\{1,\}/base16-||" <<<"$pkg")

    # Compares application extension with existing processors and runs the appropriate processor if found
    processor="$PROCESSOR_PATH/theme_$appext"
    if [[ -f "$processor" ]]; then
      "$processor" "$PACKAGE_PATH" "$pkg" "$theme"
    else
      printf "WARN: No processor found for application %s in %s. Make sure you install a processor for the application.\n" "$appext" "$PROCESSOR_PATH/" >&2
    fi

  done
}

list() {
  local selected="$1"

  case "$selected" in
  packages)
    get_packages
    ;;
  processors)
    get_processors
    ;;
  themes)
    get_themes
    ;;
  *)
    echo "Please select one of packages | processors | themes to list."
    ;;
  esac
}

main "$@"