bash_prompt.sh

build_prompt () {
    local lhs=$1
    local rhs=$2
    local save='\e[s' # Save cursor position
    local rest='\e[u' # Restore cursor to save point
    # Strip ANSI commands before counting length
    # From: https://www.commandlinefu.com/commands/view/12043/remove-color-special-escape-ansi-codes-from-text-with-sed
    rhs_stripped=$(sed "s,\x1B\[[0-9;]*[a-zA-Z],,g" <<<"$rhs")
    echo "\[${save}\e[${COLUMNS:-$(tput cols)}C\e[${#rhs_stripped}D${rhs}${rest}\]${lhs}"
}

set_color_prompt () {
    local err="$?"
    local rhs=$(printf "\e[38;5;239m[%(%d.%m.%y %H:%M:%S)T]\e[0m" -1) # -1 is current time
    local lhs="${debian_chroot:+($debian_chroot)}\[\e[01;32m\]\u@\h\[\e[00m\]:\[\e[01;34m\]\w\[\e[00m\]\n"
    if [[ $err != 0 ]]; then
        lhs+="\[\e[01;91m\][$err] \[\e[00m\]"
    fi
    lhs+="\[\e[01;34m\]\$\[\e[00m\] "
    PS1=$(build_prompt "$lhs" "$rhs")
}

set_gray_prompt () {
    local err="$?"
    local rhs=$(printf "[%(%d.%m.%y %H:%M:%S)T]" -1) # -1 is current time
    local lhs="${debian_chroot:+($debian_chroot)}\u@\h:\w \D{%F %T}\n"
    if [[ $err != 0 ]]; then
        lhs+="[$err] "
    fi
    lhs+="\$ "
    PS1=$(build_prompt "$lhs" "$rhs")
}

if [ "$color_prompt" = yes ]; then
    PROMPT_COMMAND=set_color_prompt
else
    PROMPT_COMMAND=set_gray_prompt
fi
unset color_prompt force_color_prompt