#!/bin/sh

# The MIT License (MIT)
#
# Copyright (c) 2026 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.


# gbm [options...] [good regex...] [bad regex...] [meh regex...] [files...]
#
# Good, Bad, Meh colors lines using up to 3 regular expressions, keeping all
# other input lines verbatim.
#
# For the `good` matches, a colorblind-friendly blue is used instead of green
# if either environment variable COLORBLIND or COLOR_BLIND is declared and set
# to 1.
#
# The case-insensitive-comparison option is any of `-i`, `--i`, `-ins`, or
# `--ins`. The help option is `-h`, `--h`, `-help`, or `--help`.


insensitive=0
case "$1" in
    -h|--h|-help|--help)
        awk '/^# +gbm /, /^$/ { gsub(/^# ?/, ""); print }' "$0"
        exit 0
    ;;
    -i|--i|-ins|--ins|-insensitive|--insensitive)
        insensitive=1
        shift
    ;;
esac

[ "$1" = '--' ] && shift

command='awk'
if { [ -p /dev/stdout ] || [ -t 1 ]; } && [ -e /usr/bin/stdbuf ]; then
    command='stdbuf -oL awk'
fi

${command} -v ci="${insensitive}" '
    BEGIN {
        got_good = ARGC > 1
        got_bad = ARGC > 2
        got_meh = ARGC > 3
        good = ARGV[1]
        bad = ARGV[2]
        meh = ARGV[3]
        delete ARGV[1]
        delete ARGV[2]
        delete ARGV[3]

        if (ci && IGNORECASE == "") {
            msg = "this variant of AWK lacks case-insensitive regex-matching"
            print(msg) > "/dev/stderr"
            exit 125
        }
        if (ci) IGNORECASE = 1

        # normal good-style is green, colorblind-friendly good-style is blue
        cb = ENVIRON["COLORBLIND"] != 0 || ENVIRON["COLOR_BLIND"] != 0
        good_style = cb ? "\x1b[38;2;0;95;215m" : "\x1b[38;2;0;135;95m"
        good_fmt = good_style "%s\x1b[0m\n"
        good_reset = "\x1b[0m" good_style
    }

    got_good && $0 ~ good {
        gsub(/\x1b\[0m/, good_reset)
        printf good_fmt, $0
        next
    }

    got_bad && $0 ~ bad {
        gsub(/\x1b\[0m/, "\x1b[0m\x1b[38;2;204;0;0m")
        printf "\x1b[38;2;204;0;0m%s\x1b[0m\n", $0
        next
    }

    got_meh && $0 ~ meh {
        gsub(/\x1b\[0m/, "\x1b[0m\x1b[38;2;168;168;168m")
        printf "\x1b[38;2;168;168;168m%s\x1b[0m\n", $0
        next
    }

    1
' "$@"