#!/usr/bin/env bash
set -eo pipefail

if [[ "$1" == "-h" || "$1" == "--help" ]]; then
    cat <<EOF
Usage: $(basename "$0") [-h] PATH [-N]

Display used space on disk by PATH or show top N most heavy paths inside a PATH

Options:
    -h, --help    Show this help message

EOF
    exit 0
fi

if [ -n "$2" ]; then
    du -ah "$1" 2>/dev/null \
        | sort -rh 2>/dev/null \
        | head -"$2" 2>/dev/null
else
    du -ah --max-depth=1 "$1" 2>/dev/null \
        | sort -rh 2>/dev/null
fi