Multiline Bash command prompt with user, host, path, git status, right-aligned timestamp.

.bash_profile

# Define colors
RESET='\[\033[00m\]'
FGBK='\[\033[0;30m\]' # foreground black
FGRD='\[\033[0;31m\]' # foreground red
FGGN='\[\033[0;32m\]' # foreground green
FGYL='\[\033[0;33m\]' # foreground yellow
FGBL='\[\033[0;34m\]' # foreground blue
FGMG='\[\033[0;35m\]' # foreground magenta
FGCY='\[\033[0;36m\]' # foreground cyan
FGGR='\[\033[0;37m\]' # foreground gray
FGBKBD='\[\033[1;30m\]' # foreground black bright
FGRDBD='\[\033[1;31m\]' # foreground red bright
FGGNBD='\[\033[1;32m\]' # foreground green bright
FGYLBD='\[\033[1;33m\]' # foreground yellow bright
FGBLBD='\[\033[1;34m\]' # foreground blue bright
FGMGBD='\[\033[1;35m\]' # foreground magenta bright
FGCYBD='\[\033[1;36m\]' # foreground cyan bright
FGGRBD='\[\033[1;37m\]' # foreground gray bright
BGBK='\[\033[40m\]' # background black
BGRD='\[\033[41m\]' # background red
BGGN='\[\033[42m\]' # background green
BGYL='\[\033[43m\]' # background yellow
BGBL='\[\033[44m\]' # background blue
BGMG='\[\033[45m\]' # background magenta
BGCY='\[\033[46m\]' # background cyan
BGGR='\[\033[47m\]' # background gray

# Give the hostname an emphasized color
HOSTCOLOR="$FGGRBD"
# Consider using a red background for an important server
# HOSTCOLOR="$BGRD"
# You can also set black text with a yellow background
# HOSTCOLOR="$FGBK$BGYL"

# Detect whether the current directory is a git repository.
function is_git_repository {
  git branch > /dev/null 2>&1
}

# Determine the branch/state information for this git repository.
function set_git_branch {
  # Capture the output of the "git status" command.
  git_status="$(git status 2> /dev/null)"

  # Set color based on clean/staged/dirty.
  if [[ ${git_status} =~ "working directory clean" ]]; then
    state=$FGGN
  elif [[ ${git_status} =~ "Changes to be committed" ]]; then
    state=$FGYLBD
  else
    state=$FGYLBD
  fi
  
  # Set arrow icon based on status against remote.
  remote_pattern="# Your branch is (.*) of"
  if [[ ${git_status} =~ ${remote_pattern} ]]; then
    if [[ ${BASH_REMATCH[1]} == "ahead" ]]; then
      remote="↑"
    else
      remote="↓"
    fi
  else
    remote=""
  fi
  diverge_pattern="# Your branch and (.*) have diverged"
  if [[ ${git_status} =~ ${diverge_pattern} ]]; then
    remote="↕"
  fi
  
  # Get the name of the branch.
  branch_pattern="^# On branch ([^${IFS}]*)"    
  if [[ ${git_status} =~ ${branch_pattern} ]]; then
    branch=${BASH_REMATCH[1]}
  fi

  # Set the final branch string.
  BRANCH="${state}[${branch}]${remote}$RESET"
}

# Return the prompt symbol to use, colorized based on the return value of the
# previous command.
function set_prompt_symbol () {
  # echo "set_prompt_symbol"
  if test $1 -eq 0 ; then
    PROMPT_SYMBOL="⌘"
  else
    PROMPT_SYMBOL="\[\033[0;31m\]⌘\[\033[0m\]"
  fi
}

# Set the full bash prompt.
function set_bash_prompt () {
  # echo "set_bash_prompt"
  # Set the PROMPT_SYMBOL variable. We do this first so we don't lose the 
  # return value of the last command.
  set_prompt_symbol $?

  # Set the BRANCH variable.
  if is_git_repository ; then
    set_git_branch
  else
    BRANCH=''
  fi
  
  # Fill spaces between the left and right halves
  strippedbranch=`echo $BRANCH | sed 's|\\\\\\[[^]]*\\]||g'`
  lefthalf="`whoami`@`hostname -s` `pwd | sed "s|$HOME|~|"` $strippedbranch"
  righthalf=`date '+%a %b %d %T'`
  let fillsize=${COLUMNS}-${#lefthalf}-${#righthalf}-1
  fill=`printf ' %.0s' {1..300}` # 300 spaces
  fill=${fill:0:$fillsize}

  # Set the bash prompt variable.
  PS1="\n$FGGR\u@$HOSTCOLOR\h$RESET $FGGR\w$RESET ${BRANCH}$fill$FGGR\d \T$RESET\n\
${PROMPT_SYMBOL} "
}

# Tell bash to execute this function just before displaying its prompt.
PROMPT_COMMAND=set_bash_prompt

To enable this prompt:

1. Enable the Pro theme in Terminal prefs
2. Uncheck "use bold fonts" and check "use bright colors for bold text"
3. Set the normal gray color to be 50% black
4. Save the following in your .bash_profile and restart Terminal