bash_prompt.bash

# Variables and for PS1 prompt
# source: http://welinux.ru/post/7293/

# Variables for convenient PS1 construction
#
# Note: Wrapping the tput output in \[ \] is recommended by the Bash man page.
# This helps Bash ignore non-printable characters so that it correctly calculates the size of the prompt.
# See: https://wiki.archlinux.org/index.php/Bash/Prompt_customization
#
# \[   Begin a sequence of non-printing characters. (like color escape sequences).
#      This allows bash to calculate word wrapping correctly.
#
# \]   End a sequence of non-printing characters.

RESET="\[$(tput sgr0)\]"
BOLD="\[$(tput bold)\]"

# 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="\[$(tput setaf 7)\]"

# Node.js version
function prompt_node() {
    local version output
    version="$(node --version 2>/dev/null)"
    [[ $? != 0 ]] && return;
    output="$(echo "$version" | awk -F '.' '{print $1}')"
    echo -en " ${output}"
}

# Git status.
# Adapted from: https://github.com/cowboy/dotfiles/
# Source: https://github.com/miripiruni/dotfiles/
function prompt_git() {
    local status output flags
    status="$(git status 2>/dev/null)"
    [[ $? != 0 ]] && return;
    output="$(echo "$status" | awk '/# Initial commit/ {print "(init)"}')"
    [[ "$output" ]] || output="$(echo "$status" | awk '/^On branch/ {print $4}')"
    [[ "$output" ]] || output="$(git branch | perl -ne '/^\* (.*)/ && print $1')"
    flags="$(
    echo "$status" | awk 'BEGIN {r=""} \
        /^Changes to be committed:$/ {r=r "+"}\
        /^Changes not staged for commit:$/ {r=r "*"}\
        /^Untracked files:$/ {r=r "?"}\
        END {print r}'
    )"
    flags="${flags}$(prompt_git_stash)$(prompt_git_rev)"
    if [[ "$flags" ]]; then
        output="${output} ${flags}"
    fi
    echo -en " ${output}"
}

# Git whoami
# Show current directory git Username and Email (not global git config)
function prompt_git_whoami() {
    local name email
    name="$(git config --local user.name 2>/dev/null)"
    email="$(git config --local user.email 2>/dev/null)"
    [[ $? != 0 ]] && return;
    echo -en "${name} <${email}>"
}

# Git stash
function prompt_git_stash {
    local count
    count="$(git stash list 2> /dev/null | wc -l)"
    [[ $count != "0" ]] && echo -en "^${count}"
}

# Source https://gist.github.com/dariok/0205036e6d4c473a05a9469022f87f3f
function check_git_rev() {
    # Check the current dir is actually a repository
    #git status &> /dev/null || return 2
    # If we are not on a branch we will get annoying errors if we don't do this check
    git branch | grep -qE '^\* \((no branch|detached from .*|fatal: )\)' && return 1
    return 0
}

function prompt_git_rev() {
    local ahead behind

    if ! check_git_rev; then
        return;
    fi

    ahead="$(git rev-list --count @{u}..HEAD 2> /dev/null)"
    behind="$(git rev-list --count HEAD..@{u} 2> /dev/null)"

    [[ $? != 0 ]] && return;

    echo -en " ↑${ahead} ↓${behind}"
}

# Fix Windows Bash EOL
# See: https://stackoverflow.com/a/37074809/1284255
function echo_new_line() {
  echo -e "\n "
}

# Personal colors for root
case $(id -u) in
    0)
        STARTCOLOUR=${RED};
        PROMPT="${BOLD}${RED} #";
        ;;
    *)
        STARTCOLOUR=${YELLOW};
        PROMPT="${BOLD}${GREEN} >";
        ;;
esac

# Prompt

# Time
# PS1="${CYAN}\t "

# Username
PS1="${STARTCOLOUR}\u"
# @
PS1+="${RESET}@"
# Host
PS1+="${CYAN}\h "

# Working directory
PS1+="${BOLD}${GREEN}\w"

# jobs:
PS1+="${RESET}${YELLOW} jobs:"
# The number of processes you've suspended in this shell by hitting ^Z
PS1+="${BOLD}\j${RESET}"

# Node.js:
if [ -x "$(command -v node)" ]; then
    PS1+="\$(prompt_node)"
fi

# Git
if [ -x "$(command -v git)" ]; then
    # Git details
    PS1+="${YELLOW}\$(prompt_git)"

    # Git whoami
    PS1+=" ${YELLOW}\$(prompt_git_whoami)"
fi

# Newline
PS1+="${RESET}\$(echo_new_line)"

# PROMPT
PS1+="$PROMPT "
# Reset color
PS1+="${RESET}"

# vim: syntax=sh