COLOUR_RED="\[\033[0;31m\]"
COLOUR_GREEN="\[\033[0;32m\]"
COLOUR_BLUE="\[\033[0;34m\]"
COLOUR_NONE="\[\e[0m\]"

function git_prompt {
  local STATUS=`git status 2>&1`
  if [[ "$STATUS" == *'Not a git repository'* ]]; then
    echo "$"
  else
    if [[ "$STATUS" == *'working directory clean'* ]]; then
      echo "${COLOUR_GREEN}\[±\]${COLOUR_NONE}"
    else
      if [[ "$STATUS" == *"Changes not staged for commit:"* ]]; then
        echo "${COLOUR_RED}\[±\]${COLOUR_NONE}"
      elif [[ "$STATUS" == *"Untracked files:"* ]]; then
        echo "${COLOUR_RED}\[±\]${COLOUR_NONE}"
      else
        echo "${COLOUR_BLUE}\[±\]${COLOUR_NONE}"
      fi
    fi
  fi
}
export PS1='\w $(git_prompt) '