zsh_prompt

# Display seconds in human readable fromat
# Based on http://stackoverflow.com/a/32164707/3859566
# USAGE:
#   _displaytime <seconds>
_displaytime() {
  local T=$1
  local D=$((T/60/60/24))
  local H=$((T/60/60%24))
  local M=$((T/60%60))
  local S=$((T%60))
  [[ $D > 0 ]] && printf '%dd %dh' $D $H
  [[ $H > 0 ]] && [[ $D == 0 ]] && printf '%dh %dm' $H $M
  [[ $M > 0 ]] && [[ $H == 0 ]] && printf '%dm %ds' $M $S
  [[ $M == 0 ]] && printf '%ds' $1
}

function prompt {
  # Retirve exit code of last command to use in exit_code
  # Must be captured before any other command in prompt is executed
  RETVAL=$?

  # Option EXTENDED_GLOB is set locally to force filename generation on
  # argument to conditions, i.e. allow usage of explicit glob qualifier (#q).
  # See the description of filename generation in
  # http://zsh.sourceforge.net/Doc/Release/Conditional-Expressions.html
  setopt EXTENDED_GLOB LOCAL_OPTIONS

  [[ $RETVAL != 0 ]] && echo -n "%{$fg_bold[red]%}E($RETVAL)%{$reset_color%} "
  if [[ $EXEC_TIME_duration -ge 2 ]]; then
    echo -n "%{$fg_bold[magenta]%}$(_displaytime $EXEC_TIME_duration)%{$reset_color%} "
  fi
  if [[ $LOGNAME != $USER ]] || [[ $UID == 0 ]] || [[ -n $SSH_CONNECTION ]]; then
    echo -n "%{$fg[magenta]%}%n%{$reset_color%} at %{$fg[yellow]%}%m%{$reset_color%} "
  fi
  echo -n "%{$fg_bold[blue]%}λ%{$reset_color%} "
}

PROMPT="$(prompt)"
export PROMPT

# Execution time start
exec_time_preexec_hook() {
  EXEC_TIME_start=$(date +%s)
}

# Execution time end
exec_time_precmd_hook() {
  [[ -n $EXEC_TIME_duration ]] && unset EXEC_TIME_duration
  [[ -z $EXEC_TIME_start ]] && return
  local EXEC_TIME_stop=$(date +%s)
  EXEC_TIME_duration=$(($EXEC_TIME_stop - $EXEC_TIME_start))
  unset EXEC_TIME_start
}

autoload -Uz add-zsh-hook
# Add exec_time hooks
add-zsh-hook preexec exec_time_preexec_hook
add-zsh-hook precmd exec_time_precmd_hook