color bash, source color https://github.com/s0md3v/Arjun/blob/master/arjun/core/colors.py

color.sh

#!/bin/bash

#usage
# bash color.sh "{{red}}hello {{blue}}marcos" # singel color
# bash color.sh "{{red}}hello [start]{{red}}how are you[end]"

text=""
args="$@"
declare -A colors=(\
	["{{reset}}"]="\\\033[0m" \
	["{{black}}"]="\\\033[0;30m" \
	["{{red}}"]="\\\033[0;31m" \
	["{{green}}"]="\\\033[0;32m" \
	["{{yellow}}"]="\\\033[0;33m" \
	["{{blue}}"]="\\\033[0;34m" \
	["{{purple}}"]="\\\033[0;35m" \
	["{{cyan}}"]="\\\033[0;36m" \
	["{{white}}"]="\\\033[0;37m" \
	["{{ok}}"]="\\\033[1;92m[✓]" \
	["{{good}}"]="\\\033[1;32m[+]" \
	["{{bad}}"]="\\\033[1;91m[-]" \
	["{{unknow}}"]="\\\033[1;94m[?]" \
	["{{info}}"]="\\\033[1;93m[!]" \
)

parseColor(){
	for i in ${args}
	do
		color="$(echo "${i}" | grep -o -E '\{\{[a-zA-Z]+\}\}')"
		if [ -z "${color}" ]
		then
			text+=$(echo "${i}") 
		else
			text+=$(echo "${i}" | sed "s/$color/${colors[${color}]}/g" | sed 's/$/\\033[0m /') 
		fi
	done
}

manyWords="$(echo ${args} | grep -o -E '\[start\](.*)\[end\]')" # get tag start
getColorManyWords="$(echo ${manyWords} | grep -o -E '\{\{[a-zA-Z]+\}\}')" # get color from tag start
if [ ! -z "${manyWords}" ] 
then
	args="$(echo ${args} | sed -E 's/\[start\](.*)\[end\]/{start_end_here}/g')" # replace start tag to {start_end_here} for replace in future
	parseColor ${args} # replace tag color 
	finalManyWords=$(echo ${manyWords} | sed -E 's/\[start\]|\[end\]//g' | sed "s/${getColorManyWords}/\\\\${colors[${getColorManyWords}]}/g"| sed 's/$/\\\\033[0m /') # parse tag start
	text=$(echo "${text}" | sed "s/{start_end_here}/${finalManyWords}/g") # replace tag ${start_end_here} to tag start after parse
else
	parseColor ${args}
fi
echo -e ${text} 1>&2