#!/bin/sh
##############################################################################
# Copyright 2020 Thomas E. Dickey                                            #
# Copyright 2016 Free Software Foundation, Inc.                              #
#                                                                            #
# 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, distribute    #
# with modifications, 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 ABOVE 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.                                                  #
#                                                                            #
# Except as contained in this notice, the name(s) of the above copyright     #
# holders shall not be used in advertising or otherwise to promote the sale, #
# use or other dealings in this Software without prior written               #
# authorization.                                                             #
##############################################################################
# $Id: tput-colorcube,v 1.2 2020/02/02 23:34:34 tom Exp $
# Use this script to print an xterm-style color cube, e.g., as done in
# the xterm 88colors2.pl and 256colors2.pl scripts.

failed() {
	printf "?? $*\n" >&2
	exit 1
}

newline() {
	tput op
	printf "\n"
}

if [ $# = 1 ]
then
	myterm=$1
elif [ $# = 0 ]
then
	myterm=$TERM
else
	failed "expected one parameter or none"
fi

colors=$(tput -T $myterm colors 2>/dev/null)
if [ ${colors:-0} -le 0 ]
then
	myterm=${myterm%%-color}
	colors=$(tput -T $myterm colors 2>/dev/null)
fi
if [ ${colors:-0} -le 0 ]
then
	failed "terminal $myterm does not support color"
fi

printf "System colors:\n"

color=0
inrow=$colors
to_do=$colors
[ $colors -gt 256 ] && colors=256
[ $inrow  -gt   8 ] && inrow=8
[ $to_do  -gt  16 ] && to_do=16
while [ $color -lt $to_do ]
do
	[ $color = $inrow ] && newline
	tput setab $color
	printf '  '
	color=$(expr $color + 1)
done
newline

[ $colors -le 16 ] && exit

if [ $colors = 256 ]
then
	cube=6
	ramp=232
elif [ $colors -ge 88 ]
then
	cube=4
	ramp=80
else
	exit
fi

printf "\n"
printf "Color cube, ${cube}x${cube}x${cube}:\n"
g=0
cube2=$(expr $cube \* $cube)
while [ $g -lt $cube ]
do
	r=0
	while [ $r -lt $cube ]
	do
		b=0
		while [ $b -lt $cube ]
		do
			color=$(expr 16 + \( $r \* $cube2 \) + \( $g \* $cube \) + $b)
			tput setab $color
			printf '  '
			b=$(expr $b + 1)
		done
		tput op
		printf ' '
		r=$(expr $r + 1)
	done
	newline
	g=$(expr $g + 1)
done

printf "\n"
printf "Grayscale ramp:\n"
color=$ramp
while [ $color -lt $colors ]
do
	tput setab $color
	printf '  '
	color=$(expr $color + 1)
done
newline
# vi:ts=4 sw=4