.bash_ps1

#!/bin/bash

# ------------------------------------------------------------------------------
# Colors and formatting options
#

# only assign colors if terminal is present
if $(tty -s); then
    resetFormatting="$(tput sgr0)"
    bold="$(tput bold)"

    # regular colors
    black="$(tput setaf 0)"
    red="$(tput setaf 1)"
    green="$(tput setaf 2)"
    yellow="$(tput setaf 3)"
    blue="$(tput setaf 4)"
    magenta="$(tput setaf 5)"
    cyan="$(tput setaf 6)"
    white="$(tput setaf 7)"

    # High intensity colors
    blackH="${bold}${black}"
    redH="${bold}${red}"
    greenH="${bold}${green}"
    yellowH="${bold}${yellow}"
    blueH="${bold}${blue}"
    magentaH="${bold}${magenta}"
    cyanH="${bold}${cyan}"
    whiteH="${bold}${white}"

    # background colors
    blackB="$(tput setab 0)"
    redB="$(tput setab 1)"
    greenB="$(tput setab 2)"
    yellowB="$(tput setab 3)"
    blueB="$(tput setab 4)"
    magentaB="$(tput setab 5)"
    cyanB="$(tput setab 6)"
    whiteB="$(tput setab 7)"
fi

# ------------------------------------------------------------------------------
# Aliases for host and user names
#

PRIVATES="$HOME/.bash_privates"
if [[ -f "$PRIVATES" && -r "$PRIVATES" ]]; then
    source "$PRIVATES" && USE_PRIVATES=true
else
    USE_PRIVATES=false
fi

# re-implement the following in $PRIVATES for sensitive data
if [[ $USE_PRIVATES == false ]]; then
    # Provide user name alias for prompt
    __user_alias() {
        case `whoami` in
            root)
                echo -n "###"
                ;;
            foo)
                echo -n "bar"
                ;;
            *)
                echo -n ""
                ;;
        esac
    }

    # Provide host tags 
    case `hostname` in
        *.foo.bar)
            HOST_TAGS=":server:"
            ;;
        larry* | curly* | moe*)
            HOST_TAGS=":workstation:"
            ;;
        *)
            HOST_TAGS=""
            ;;
    esac
    export HOST_TAGS

    # Provide host alias names
    case `hostname` in
        foo)
            HOST_ALIAS="bar"
            ;;

        baz)
            HOST_ALIAS="blah"
            ;;
    esac

    [ -n "${HOST_ALIAS}" ] && export HOST_ALIAS

    # Select host name color based on HOST_TAGS environment variable
    case ${HOST_TAGS} in
        *:server:*)
            HOST_COLOR=${black}${redB}
            ;;
        *:workstation:*)
            HOST_COLOR=${blue}
            ;;
        *)
            HOST_COLOR=${white}${blackB}
            ;;
    esac
fi

# ------------------------------------------------------------------------------
# Bash PROMPT
#


function __prompt_date {
    echo -n `date +%H:%M`
}

# Username or alias
function __prompt_username {
    if [[ "$(type -t __user_alias)" == "function" ]]; then
        local user_alias=$(__user_alias)
    fi
    if [[ -n "$user_alias" ]]; then
        echo -n "$user_alias"
    else
        echo -n "$(whoami | cut -c1-8)"
    fi
}

# Hostname or alias
function __prompt_hostname {
   if [[ -n ${HOST_ALIAS} ]]; then
       echo -n ${HOST_ALIAS}
   else
       echo -n "$(hostname -s | cut -c1-16)"
   fi
}

# SSH agent indicator
function __prompt_ssh_agent {
    if [[ -n "${SSH_CLIENT}" ]] && [[ -n "${SSH_AUTH_SOCK}" ]] && [[ -e "${SSH_AUTH_SOCK}" ]]; then
        echo -n "@"
    fi
}

# SSH session session indicator
function __prompt_ssh {
    if [[ -n "$SSH_CLIENT" ]]; then
        echo -n 'ssh'
    fi
}

# Show version controlled repository status.
# vcprompt is used if installed, otherwise __git_ps1 will be tried as well.
# Install vcsprompt -> hg clone https://bitbucket.org/mitsuhiko/vcprompt
export GIT_PS1_SHOWDIRTYSTATE="yes"
export GIT_PS1_SHOWUPSTREAM="no"
export GIT_PS1_SHOWUNTRACKEDFILES="yes"
function __prompt_vcs {
    if [[ $(which vcprompt 2>/dev/null) ]]; then
        vcprompt -f " (%n:%b%m%u)"
    elif [[ $(type -t __git_ps1) == "function" ]]; then
        __git_ps1 " (%s)"
    fi
}



# Support function to compactify a path
# copied: http://stackoverflow.com/questions/3497885/code-challenge-bash-prompt-path-shortener
function __dir_chomp {
    local p=${1/#$HOME/\~} b s
    # Remove [ and ] from strings
    # (also, regular expression matching on [ ] below creates infinite recursion.)
    p=${p//[/ }
    p=${p//]/ }
    # Remove multiple spaces, don't need them
    p=${p//  / }
    s=${#p}
    while [[ $p != ${p//\/} ]] && (($s>$2))
    do
        p=${p#/}
        [[ $p =~ \.?. ]]
        b=${b:+${b}/}${BASH_REMATCH[0]}
        p=${p#*/}
        ((s=${#b}+${#p}))
    done
    #echo ${b/\/~/\~}${b+/}$p
    echo ${b/\/~/\~}${b:+/}$p
}

# Compact version of current working directory
function __prompt_pwd {
    echo -n $(__dir_chomp  "$(pwd)" 40)
}

# Visual indicator of last exit code 
function __prompt_last {
  if [[ $EUID -eq 0 ]]; then
      if [[ ${RET} = "0" ]]; then
          echo -n "#"
      else
          echo -n '!!! #'
      fi
  else
      if [[ ${RET} = "0" ]]; then
          echo -n "\$"
      else
          echo -n '$%&!'
      fi
  fi
}

# Append the storage of exit code to prompt command
if [[ $PROMPT_COMMAND =~ ^.*\;[[:space:]$'\n'$'\r']*$ ]]; then
    PROMPT_COMMAND="${PROMPT_COMMAND%;*}"
fi

export PROMPT_COMMAND="export RET=\$?${PROMPT_COMMAND:+;${PROMPT_COMMAND}}"

# Set up prompt
function __prompt_activate {

    # Set title in xterm*
    case $TERM in
        xterm*|rxvt*)
            TITLEBAR='\[\033]0;\u@\h:\w\007\]'
            ;;
        *)
            TITLEBAR=""
            ;;
    esac

# Set the prompt 
PS1="${TITLEBAR}\
\[${redH}\]\$(__prompt_date)\[${resetFormatting}\] \
\[${yellowH}\]\$(__prompt_username)\[${resetFormatting}\]\
\[${magentaH}\]@\[${resetFormatting}\]\
\[${HOST_COLOR}\]\$(__prompt_hostname)\[${resetFormatting}\]\
\[${white}${magentaB}\]\$(__prompt_ssh_agent)\[${resetFormatting}\]\
\[${black}${magentaB}\]\$(__prompt_ssh)\[${resetFormatting}\] \
\[${blueH}\]\$(__prompt_pwd)\[${resetFormatting}\]\
\[${greenH}\]\$(__prompt_vcs)\[${resetFormatting}\]\
\[${magenta}\]\$(__prompt_last)\[${resetFormatting}\] "
PS2='> '
PS4='+ '
}


# Activate the prompt code
__prompt_activate