git aware prompt

.bashrc

function git-branch-name {
    echo `git symbolic-ref HEAD --short 2> /dev/null || (git branch | sed -n 's/\* (*\([^)]*\))*/\1/p')`
}
function git-dirty {
    [[ `wc -l <<< "$1" ` -eq 1  ]] || echo "*"
}
function git-unpushed {
    if [[ "$1" =~ ("behind "([[:digit:]]*)) ]]
    then
        echo -n "-${BASH_REMATCH[2]}"
    fi
    if [[ "$1" =~ ("ahead "([[:digit:]]*)) ]]
    then
        echo -n "+${BASH_REMATCH[2]}"
    fi
}
function gitcolor {
    st=$(git status -b --porcelain 2>/dev/null)
    [[ $? -eq 0 ]] || return

    if [[ $(git-dirty "$st") == "*" ]];
    then
        echo -e "\033[31m"
    elif [[ $(git-unpushed "$st") != "" ]];
    then
        echo -e "\033[33m"
    else
        echo -e "\033[32m"
    fi
}
function gitify {
    st=$(git status -b --porcelain 2>/dev/null)
    [[ $? -eq 0 ]] || return
    dirty=$(git-dirty "$st")
    unpushed=$(git-unpushed "$st")
    echo -e " ($(git-branch-name)$dirty$unpushed)"
}

PS1="\[\033[33m\](\h)\[\033[00m\]-\W\[\$(gitcolor)\]\$(gitify)\[\033[00m\]\$ "