multi-line PS1 with git branch, last command status & last command timer

.bash_profile

# colors with control characters already in place, no need to echo them again when using
# adapted from: https://stackoverflow.com/a/28115284
RESTORE=$(echo -en '\001\033[0m\002')
RED=$(echo -en '\001\033[00;31m\002')
GREEN=$(echo -en '\001\033[00;32m\002')
YELLOW=$(echo -en '\001\033[00;33m\002')
BLUE=$(echo -en '\001\033[00;34m\002')
MAGENTA=$(echo -en '\001\033[00;35m\002')
PURPLE=$(echo -en '\001\033[00;35m\002')
CYAN=$(echo -en '\001\033[00;36m\002')
LIGHTGRAY=$(echo -en '\001\033[00;37m\002')
LRED=$(echo -en '\001\033[01;31m\002')
LGREEN=$(echo -en '\001\033[01;32m\002')
LYELLOW=$(echo -en '\001\033[01;33m\002')
LBLUE=$(echo -en '\001\033[01;34m\002')
LMAGENTA=$(echo -en '\001\033[01;35m\002')
LPURPLE=$(echo -en '\001\033[01;35m\002')
LCYAN=$(echo -en '\001\033[01;36m\002')
WHITE=$(echo -en '\001\033[01;37m\002')

# timer functions adapted from https://jakemccrary.com/blog/2015/05/03/put-the-last-commands-run-time-in-your-bash-prompt/
function timer_start() {
    timer=${timer:-$SECONDS}
}

# sets $timer_show with the runtime of the last command
# empty if the command ran in < 1s
# units switch at 1m31s and 1hr31m0s
function timer_stop() {
    secs=$(($SECONDS - $timer))
    unset timer

    if [ $secs -lt 1 ]; then
        timer_show=" "
        return 0
    fi

    hours=$(($secs / 3600))
    mins=$(($secs / 60))

    if [ $secs -gt 90 ]; then
        secs=$(($secs % 60))

        if [ $mins -gt 90 ]; then
            mins=$(($mins % 60))
            timer_show="${hours}hr${mins}m${secs}s"
        else
            timer_show="${mins}m${secs}s"
        fi
    else
        timer_show="${secs}s"
    fi
    timer_show=" $timer_show "
}

trap 'timer_start' DEBUG

# sets $cmd_face with a colored emoticon representing the exit status of the last command
function smile() {
    if [ $? -eq 0 ]; then
        cmd_face="${GREEN}:-)${RESTORE}"
    else
        cmd_face="${RED}8-(${RESTORE}"
    fi
}

# sets $vc_branch with the current git branch
function vc_branch() {
    vc_branch=`git rev-parse --abbrev-ref HEAD 2>/dev/null`
    if [ "$vc_branch" != "" ]; then
        vc_branch="${LPURPLE}[${vc_branch}]${RESTORE} "
    fi
}

# order matters here: smile needs to be first to check the last command and timer_stop
# needs to be last in order to time the next command rather than the prompt commands
if [ "$PROMPT_COMMAND" == "" ]; then
    PROMPT_COMMAND="smile; vc_branch; timer_stop"
else
    PROMPT_COMMAND="smile; vc_branch; $PROMPT_COMMAND; timer_stop"
fi

if [ "$PS1" ]; then
    # bash 3.0 and line-wrapping compatible version:
    # gives the following (where smiley indicates last cmd sucessfully ran)
    # powered by the functions above and $PROMPT_COMMAND
    #
    # [HH:MM AM/PM] user@host: [current branch (if any)] $PWD
    # :-) / 8-( {last command runtime (s)} $

    PS1="${BOLD}[\@]${RESTORE} ${YELLOW}\u${RESTORE}@${GREEN}\h \${vc_branch}${BLUE}\w/${RESTORE} \n \${cmd_face}\${timer_show}\$ "
fi