#!/bin/sh

# The MIT License (MIT)
#
# Copyright © 2020-2025 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.


# uawk [awk condition...] [filenames...]
#
# Underline (lines) satisfying an AWK condition/expression, keeping all other
# lines the same. When not given a condition, all lines are underlined.


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

cond="${1:-1}"
[ $# -gt 0 ] && shift

awk '
    { low = lower = tolower($0) }

    '"${cond}"' {
        gsub(/\x1b\[0m/, "\x1b[0m\x1b[4m")
        printf "\x1b[4m%s\x1b[0m\n", $0; fflush()
        next
    }

    { print; fflush() }
' "$@"