.bash_prompt

#!/bin/sh

# use colours in terminal
if [[ $COLORTERM = gnome-* && $TERM = xterm ]] && infocmp gnome-256color > /dev/null 2>&1; then
    export TERM="gnome-256color"
elif infocmp xterm-256color > /dev/null 2>&1; then
    export TERM="xterm-256color"
fi

if tput setaf 1 &> /dev/null; then
    tput sgr0
    export bold=$(tput bold)
    export reset=$(tput sgr0)
    export black=$(tput setaf 0)
    export blue=$(tput setaf 33)
    export cyan=$(tput setaf 37)
    export green=$(tput setaf 64)
    export orange=$(tput setaf 166)
    export pink=$(tput setaf 9)
    export purple=$(tput setaf 125)
    export red=$(tput setaf 124)
    export violet=$(tput setaf 61)
    export white=$(tput setaf 15)
    export yellow=$(tput setaf 136)
else
    export bold=""
    export reset="\e[0m"
    export black="\e[1;30m"
    export blue="\e[1;34m"
    export cyan="\e[1;36m"
    export green="\e[1;32m"
    export orange="\e[1;33m"
    export pink="\e[1;31m"
    export purple="\e[1;35m"
    export red="\e[1;31m"
    export violet="\e[1;35m"
    export white="\e[1;37m"
    export yellow="\e[1;33m"
fi

# highlight the user and host name when logged in as root
if [[ $(id -un) == "root" ]] || [[ "$USER" == "root" ]]; then
    userStyle="${pink}"
    hostStyle="${pink}"
else
    userStyle="${orange}"
    hostStyle="${yellow}"
fi

function __prompt_git_branch {

    if [[ ! "$BASH_PROMPT_SHOW_GIT" =~ ^(true|yes|y|on|1|TRUE|YES|Y|ON)$ ]]; then
        return
    fi

    local branch=""
    # check if the current directory is in a git repository
    if [ $(git rev-parse --is-inside-work-tree &> /dev/null; echo "${?}") -eq 0 ]; then

        branch="$(git symbolic-ref --quiet --short HEAD 2> /dev/null || \
            git rev-parse --short HEAD 2> /dev/null || \
            echo '(unknown)')"

        echo "${branch}"
    else
        return
    fi
}

function __prompt_git_status {

    if [[ ! "$BASH_PROMPT_SHOW_GIT" =~ ^(true|yes|y|on|1|TRUE|YES|Y|ON)$ ]]; then
        return
    fi

    local status=""
    # check if the current directory is in a git repository
    if [ $(git rev-parse --is-inside-work-tree &> /dev/null; echo "${?}") -eq 0 ]; then
        # check if the current directory is in .git before running git checks
        if [ "$(git rev-parse --is-inside-git-dir 2> /dev/null)" == 'false' ]; then
            # ensure the index is up-to-date
            git update-index --really-refresh -q &> /dev/null
            # check for uncommitted changes in the index
            if ! $(git diff --quiet --ignore-submodules --cached); then
                status+='+'
            fi
            # check for unstaged changes
            if ! $(git diff-files --quiet --ignore-submodules --); then
                status+='!'
            fi
            # check for untracked files
            if [ -n "$(git ls-files --others --exclude-standard)" ]; then
                status+='?'
            fi
            # check for stashed files
            if $(git rev-parse --verify refs/stash &> /dev/null); then
                status+='$'
            fi
        fi
        [ -n "${status}" ] && status="[${status}]"
        echo "${status}"
    else
        return
    fi
}

function prompt_command {

    # code
    local code=$?
    if [ $code -ne 0 ]; then
        code=" \[${reset}${pink}\](${code})"
    else
        code=""
    fi
    # git
    local git=""
    local branch=$(__prompt_git_branch)
    [ -n "${branch}" ] && git=" \[${reset}${white}\]on \[${bold}${violet}\]${branch}"
    local status=$(__prompt_git_status)
    [ -n "${status}" ] && git+=" \[${reset}${blue}\]${status}"

    PS1="\[\033]0;\w\007\]"
    PS1+="\[${bold}${userStyle}\]\u "           # {user}
    PS1+="\[${reset}${white}\]at "              # at
    PS1+="\[${bold}${hostStyle}\]\h "           # {host}
    PS1+="\[${reset}${white}\]in "              # in
    PS1+="\[${bold}${green}\]\w"                # {dir}
    PS1+="${git}"                               # on {branch} {info}
    PS1+="${code}"                              # {code}
    PS1+="\[${reset}${white}\] \$ \[${reset}\]" # $
    export PS1

    PS2="\[${white}\]→ \[${reset}\]"
    export PS2
}