color_print

#!/usr/bin/env bash
set -eu

#######################################
# Function: Add color to output
# Parameters:
#   -n: Output with a newline
#   -p: Disable prefixes like [INFO]
#   $1: Color code (0~255) or specific string
#   $2: String to be colored
# Output:
#   Colored string
#######################################
function print_usage() {
    echo 'Usage:'
    echo '    color_print -n -p [color] [message...]'
    echo "    -n new line"
    echo "    -p prefixed output"
    echo '    [color] = 0~255 / info / warn / ok / error / tip / debug'
    echo ''
    echo "Examples:"
    echo "    color_print info 'hello world!'"
}

#######################################
# flags

declare add_new_line='false'
declare add_prefix='false'
declare option
while getopts nph option; do
    case $option in
        n) add_new_line='true' ;;
        p) add_prefix='true' ;;
        h) print_usage; exit 0; ;;
        *) print_usage; exit 1; ;;
    esac
done
shift $((OPTIND - 1))

#######################################
# constants

esc=$(printf "\033")    # Prefix used to change output color
reset="${esc}[0m"       # Reset all color and font settings
declare -r esc
declare -r reset

export ST_COLOR_INFO=33
export ST_COLOR_WARN=190
export ST_COLOR_OK=46
export ST_COLOR_ERROR=196
export ST_COLOR_TIP=215
export ST_COLOR_DEBUG=141

#######################################

if [[ $# == 0 ]] || [[ $# == 1 && ! -p /dev/stdin ]]; then
    echo "${esc}[1;38;5;9m[Error] Incorrect number of parameters.${esc}[m"
    print_usage
    exit 1;
fi

if [[ -p /dev/stdin ]]; then    # <-- make pipe work
    str=$(cat -)                # <-- make pipe work
else
    str="${*:2}"
fi
declare -r str

declare prefix=''
declare color=''
case $1 in
'info')     # Blue
    color=$ST_COLOR_INFO; prefix='[INFO] '; ;;
'warn')     # Yellow
    color=$ST_COLOR_WARN; prefix='[WARN] '; ;;
'ok')       # Green
    color=$ST_COLOR_OK; prefix='[OK] '; ;;
'error')    # Red
    color=$ST_COLOR_ERROR; prefix='[ERROR] '; ;;
'tip')      # Orange
    color=$ST_COLOR_TIP; prefix='[TIP] '; ;;
'debug')    # Purple
    color=$ST_COLOR_DEBUG; prefix='[debug] '; ;;
*)
    color=$1; ;;
esac

if [[ $add_prefix != 'true' ]]; then prefix=''; fi
if [[ $add_new_line == 'true' ]]; then
    echo "${esc}[38;5;${color}m${prefix}${str}${reset}"
else
    echo -n "${esc}[38;5;${color}m${prefix}${str}${reset}"
fi