Fix define-options.sh to respect existing environment variables

# define-options.sh
# - - -

Author: aiya000

define-options.sh

@@ -7,20 +7,13 @@
 [[ -n $BASH_TOYS_LOADED_DEFAULT_OPTIONS ]] && return
 
 dir="$(cd -- "$(dirname -- "${BASH_SOURCE:-$0}")" && pwd || exit 1)"
-source "$dir/sources/define-alt-export.sh"
 
-# TODO: Temporary overwrite variables. Shoud be fixed by using define-alt-export
-unset BASH_TOYS_INTERACTIVE_FILTER || true
-unset BASH_TOYS_DUSTBOX_DIR || true
-unset BASH_TOYS_MUSIC_PLAYER || true
-unset BASH_TOYS_POMODORO_NOTIFICATION_MUSIC || true
-unset BASH_TOYS_POMODORO_NOTIFICATION_DURATION || true
-unset BASH_TOYS_BATCAT_OPTIONS || true
-export BASH_TOYS_INTERACTIVE_FILTER=peco
-export BASH_TOYS_DUSTBOX_DIR="$HOME/.backup/dustbox"
-export BASH_TOYS_MUSIC_PLAYER=vlc
-export BASH_TOYS_POMODORO_NOTIFICATION_MUSIC="$dir/assets/notify.mp3"
-export BASH_TOYS_POMODORO_NOTIFICATION_DURATION=5
-export BASH_TOYS_BATCAT_OPTIONS=--number
+# Set default values only if variables are not already set
+[[ -z $BASH_TOYS_INTERACTIVE_FILTER ]] && export BASH_TOYS_INTERACTIVE_FILTER=peco
+[[ -z $BASH_TOYS_DUSTBOX_DIR ]] && export BASH_TOYS_DUSTBOX_DIR="$HOME/.backup/dustbox"
+[[ -z $BASH_TOYS_MUSIC_PLAYER ]] && export BASH_TOYS_MUSIC_PLAYER=vlc
+[[ -z $BASH_TOYS_POMODORO_NOTIFICATION_MUSIC ]] && export BASH_TOYS_POMODORO_NOTIFICATION_MUSIC="$dir/assets/notify.mp3"
+[[ -z $BASH_TOYS_POMODORO_NOTIFICATION_DURATION ]] && export BASH_TOYS_POMODORO_NOTIFICATION_DURATION=5
+[[ -z $BASH_TOYS_BATCAT_OPTIONS ]] && export BASH_TOYS_BATCAT_OPTIONS=--number
 
 export BASH_TOYS_LOADED_DEFAULT_OPTIONS=true