#!/bin/bash

export LANG='en_US.UTF-8'
# set column width
COLUMNS=2
# colors
green="\e[1;32m"
red="\e[1;31m"
undim="\e[0m"

mapfile -t containers < <( docker ps --format "{{.Names}} {{.Status}}" -a | awk '{ print $1,$2 }' | sed '/^\s*$/d' | tail -n +1)

IFS=$'\n' containers=($(sort <<<"${containers[*]}"))
unset IFS

out=""
for i in "${!containers[@]}"; do
    IFS=" " read name status <<< ${containers[i]}
    # color green if service is active, else red
    if [[ "${status}" == "Up" ]]; then
        out+="${name}:,${green}▲${undim},"
    else
        out+="${name}:,${red}▼${undim},"
    fi
    # insert \n every $COLUMNS column
    if [ $((($i+1) % $COLUMNS)) -eq 0 ]; then
        out+="\n"
    fi
done
out+="\n"

printf "\nDocker status:\n"
printf "$out" | column -ts $',' | sed -e 's/^/ /'