dmenu fuzzy finder written in shell script

fz.sh

#!/bin/sh

arg="${1:-.}"
arg=$(realpath -- "$arg") # Convert to absolute path
arg="${arg%/}" # Remove trailing slash

parent_dir=$(dirname -- "$arg")
file=$({ printf '.\n..\n'; find "$arg" -type f -printf '%P\n'; } | dmenu -p "File ($arg):" || exit 0)

# Handle selections
case "$file" in
    ".")
        echo "$arg"        # Current directory (absolute path)
        exit 0
        ;;
    "..")
        exec "$0" "$parent_dir"  # Restart script with parent directory
        ;;
    *)
        echo "$arg/$file"  # Absolute path + selected file
        ;;
esac