Adds a fancy theme to the default bash shell.

.bash_profile

# Some commonly used colors.
bash_reset_color='\[\e[0m\]'
bash_red='\[\e[0;31m\]'
bash_green='\[\e[0;32m\]'
bash_yellow='\[\e[0;33m\]'
bash_blue='\[\e[0;34m\]'
bash_purple='\[\e[0;35m\]'
bash_cyan='\[\e[0;36m\]'

# Displays the top-level direcory of the currently working directory.
bpwd() {
  echo `basename $(pwd)`
}

# Echoes 0 if there exists a git repo in the current working directory. A non-0
# is echoed otherwise.
git_prompt_exists() {
  git status &> /dev/null
  echo $?
}

# Echoes the branch of the git repo, of the current repository.
git_prompt_branch() {
  echo $(git rev-parse --abbrev-ref HEAD 2> /dev/null)
}

# Echoes the status of the git repo in the current working directory.
git_prompt_status() {
  INDEX=$(git status --porcelain -b)
  STATUS=""
  if [ "$(echo "$INDEX" | grep -E '^\?\? ')" != "" ]; then
    STATUS="$BASH_THEME_GIT_PROMPT_UNTRACKED$STATUS"
  fi
  if [ "$(echo "$INDEX" | grep '^A  ')" != "" ]; then
    STATUS="$BASH_THEME_GIT_PROMPT_ADDED$STATUS"
  elif [ "$(echo "$INDEX" | grep '^M  ')" != "" ]; then
    STATUS="$BASH_THEME_GIT_PROMPT_ADDED$STATUS"
  fi
  if [ "$(echo "$INDEX" | grep '^ M ')" != "" ]; then
    STATUS="$BASH_THEME_GIT_PROMPT_MODIFIED$STATUS"
  elif [ "$(echo "$INDEX" | grep '^AM ')" != "" ]; then
    STATUS="$BASH_THEME_GIT_PROMPT_MODIFIED$STATUS"
  elif [ "$(echo "$INDEX" | grep '^ T ')" != "" ]; then
    STATUS="$BASH_THEME_GIT_PROMPT_MODIFIED$STATUS"
  fi
  if [ "$(echo "$INDEX" | grep '^R  ')" != "" ]; then
    STATUS="$BASH_THEME_GIT_PROMPT_RENAMED$STATUS"
  fi
  if [ "$(echo "$INDEX" | grep '^ D ')" != "" ]; then
    STATUS="$BASH_THEME_GIT_PROMPT_DELETED$STATUS"
  elif [ "$(echo "$INDEX" | grep '^D ')" != "" ]; then
    STATUS="$BASH_THEME_GIT_PROMPT_DELETED$STATUS"
  elif [ "$(echo "$INDEX" | grep '^AD ')" != "" ]; then
    STATUS="$BASH_THEME_GIT_PROMPT_DELETED$STATUS"
  fi
  echo $STATUS
}


_git_prompt_status() {
  local retval=`git_prompt_status`
  if [ "$retval" ]; then
    echo "($retval) "
  fi
}

__prompt_command() {
  local EXIT="$?"

  BASH_THEME_GIT_PROMPT_ADDED=" ${bash_green}✚${bash_reset_color}"
  BASH_THEME_GIT_PROMPT_MODIFIED=" ${bash_blue}✹${bash_reset_color}"
  BASH_THEME_GIT_PROMPT_RENAMED=" ${bash_purple}➜${bash_reset_color}"
  BASH_THEME_GIT_PROMPT_DELETED=" ${bash_red}✖${bash_reset_color}"
  BASH_THEME_GIT_PROMPT_UNMERGED=" ${bash_yellow}═${bash_reset_color}"
  BASH_THEME_GIT_PROMPT_UNTRACKED=" ${bash_cyan}✭${bash_reset_color}"

  PS1="\n◦ "

  if test $VIRTUAL_ENV; then
    PS1+="(`basename $VIRTUAL_ENV`) "
  fi

  if [ "`pwd`" == $HOME ]; then
    PS1+="${bash_blue}""~""${bash_reset_color} "
  else
    local basename=
    PS1+="${bash_blue}"`basename "$(pwd)"`"${bash_reset_color} "
  fi

  if [ `git_prompt_exists` == 0 ]; then
    PS1+="on ${bash_green}`git_prompt_branch`${bash_reset_color} `_git_prompt_status`"
  fi

  if [ $EXIT != 0 ]; then
    PS1+="(${bash_red}$EXIT${bash_reset_color}) "
  fi

  PS1+="\n${bash_yellow}\$${bash_reset_color} "
}

export PROMPT_COMMAND=__prompt_command