#!/bin/sh

# The MIT License (MIT)
#
# Copyright © 2025 pacman64
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the “Software”), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.


# nls [options...] [folders...]
#
# Nice LS runs `ls` to show files (and folders), then colors folders and links
# using ANSI styles to make things easier to scan/read. Long numbers are also
# made easier to read using alternating ANSI styles.
#
# To declutter the output, entries for same folders, the parent folders, and
# the totals are ignored from the `ls` results.
#
# Besides the usual `ls`-specific options, this script offers easier-to-use
# extra options, where leading double-dashes are also allowed:
#
#     -group    group folders and links separately from regular files
#     -help     show this help message
#     -sort     reverse-sort by size


case "$1" in
    --h|-help|--help)
        awk '/^# +nls /, /^$/ { gsub(/^# ?/, ""); print }' "$0"
        exit 0
    ;;
esac

list='ls -al --file-type --color=never --time-style iso'

for arg in "$@"; do
    if [ "${arg}" = '--' ]; then
        shift
        break
    fi

    case "${arg}" in
        -group|--group)
            list="${list} --group-directories-first"
            shift
            continue
        ;;
        -sort|--sort)
            list="${list} -S"
            shift
            continue
        ;;
        -*)
            list="${list} ${arg}"
            shift
            continue
        ;;
    esac

    break
done

options='-MKiCRS'
if [ $# -le 1 ]; then
    options='--header=1 -MKiCRS'
fi

gap=0

for arg in "${@:-.}"; do
    if [ -L "${arg}" ]; then
        arg="$(realpath "${arg}")"
    fi
    if [ ! -d "${arg}" ]; then
        continue
    fi

    [ "${gap}" -gt 0 ] && printf "\n"
    printf "\e[7m%s\e[0m\n\n" "$(realpath "${arg}" || "${arg}")"
    gap=1

    ${list} "${arg}" | awk '
        BEGIN {
            drep = "\x1b[38;2;0;135;255m\x1b[48;2;228;228;228m&\x1b[0m"
            lrep = "\x1b[38;2;0;135;95m\x1b[48;2;228;228;228m&\x1b[0m"
        }

        / \.\.?\/$/ || /^total / { next }

        {
            gsub(/^(d[rwx-]+)/, drep)
            gsub(/^(l[rwx-]+)/, lrep)
            if (n % 5 == 0 && n > 0) print ""
            printf "%6d  %s\n", ++n, $0
        }
    ' | sed -E \
    -e 's-([0-9]{1,3})([0-9]{3})([0-9]{3})([0-9]{3})([0-9]{3})([0-9]{3})([0-9]{3})-\1\x1b[38;2;168;168;168m\2\x1b[0m\3\x1b[38;2;168;168;168m\4\x1b[0m\5\x1b[38;2;168;168;168m\6\x1b[0m\7-g' \
    -e 's-([0-9]{1,3})([0-9]{3})([0-9]{3})([0-9]{3})([0-9]{3})([0-9]{3})-\1\x1b[38;2;168;168;168m\2\x1b[0m\3\x1b[38;2;168;168;168m\4\x1b[0m\5\x1b[38;2;168;168;168m\6\x1b[0m-g' \
    -e 's-([0-9]{1,3})([0-9]{3})([0-9]{3})([0-9]{3})([0-9]{3})-\1\x1b[38;2;168;168;168m\2\x1b[0m\3\x1b[38;2;168;168;168m\4\x1b[0m\5-g' \
    -e 's-([0-9]{1,3})([0-9]{3})([0-9]{3})([0-9]{3})-\1\x1b[38;2;168;168;168m\2\x1b[0m\3\x1b[38;2;168;168;168m\4\x1b[0m-g' \
    -e 's-([0-9]{1,3})([0-9]{3})([0-9]{3})-\1\x1b[38;2;168;168;168m\2\x1b[0m\3-g' \
    -e 's-([0-9]{1,3})([0-9]{3})-\1\x1b[38;2;168;168;168m\2\x1b[0m-g'
done | less ${options}