bash_prompt_colorizer.sh

#!/bin/bash
# Tested on Debian based distros

# USR is sudo caller first or USR root
USR=
if [ `id -u` -eq 0 ] && [ "$SUDO_USER" != "root" ] && [ ! -z $SUDO_USER ] ; then
    USR=$SUDO_USER
elif [ `id -u` -ne 0 ]; then
    USR=`whoami`
else
    USR=root
fi

# Get USR's bashrc file
BASHRC=`getent passwd $USR | cut -d : -f6`/.bashrc
grep -sq RCol $BASHRC && echo "Settings already applied." || \
{
    echo "export PROMPT_COMMAND=__prompt_command  # Func to gen PS1 after CMDs

    function __prompt_command() {
        local EXIT=\"\$?\"             # This needs to be first
        PS1=\"\"

        local RCol='\[\e[0m\]'

        local Red='\[\e[0;31m\]'
        local Gre='\[\e[0;32m\]'
        local BYel='\[\e[1;33m\]'
        local BBlu='\[\e[1;34m\]'
        local Pur='\[\e[0;35m\]'

        if [ \$EXIT != 0 ]; then
            PS1+=\"\${Red}\${EXIT}:\u\${RCol}\"      # Add red if exit code non 0
        else
            PS1+=\"\${Gre}\${EXIT}:\u\${RCol}\"
        fi

        PS1+=\"\${RCol}@\${BBlu}\h \${Pur}\W\${BYel}\$ \${RCol}\"
    }" >> $BASHRC && echo "$BASHRC has been updated"
}