__truncate_left() {
    local str="$1"
    local maxlen="$2"
    local trunc_symbol="$3"
    local sep_symbol="$4"

    # get minimum length to not truncate a long name
    if [ -n "$sep_symbol" ]
    then
        local component=${1##*$sep_symbol}
        maxlen=$(( ( maxlen < ${#component} ) ? ${#component} : maxlen ))
    fi

    # truncation point
    local offset=$(( ${#str} - maxlen ))

    if [ ${offset} -gt "0" ]
    then
        #truncation is needed
        str=${str:$offset:$maxlen}  #truncate
        str=${trunc_symbol}/${str#*/}  #add symbol
    fi
    echo "$str"
}

__truncate_dir() {
    dir=${1/#$HOME/\~}            #gain some place with '~'
    __truncate_left "$dir" 25 '…' '/'
}

__tpwd() {
    __truncate_dir "$PWD"
}

__bash_prompt_command() {
    local pwdmaxlen=25
    local trunc_symbol="…"

    PROMPT_PWD=$(__tpwd)
}


__set_bash_ps1() {
    case $TERM in
     xterm*|rxvt*)
         local TITLEBAR='\[\033]0;\u:${NEW_PWD}\007\]'
          ;;
     *)
         local TITLEBAR=""
          ;;
    esac

    # load color vars
    source "$DOTFILES_BASH_DIR/ansi_colors"

    # colorized:
    PS1="${TITLEBAR} ${B}[${UC}\u@\h ${G}\${PROMPT_PWD}${B}]${UC}\\$ ${NONE}"
    # without colors:
    #PS1="${TITLEBAR}[\u@\h \${NEW_PWD}]\\$ "
    # extra backslash in front of \$ to make bash colorize the prompt
}

PROMPT_COMMAND=__bash_prompt_command
__set_bash_ps1
unset __set_bash_ps1

# vim: ft=sh