Bootstrap new Linux and OSX systems with my dotfiles and packages

bootstrap.sh

#!/bin/bash

GITREPO=ssh://haldean@haldean.org/srv/dotfiles.git
APT_PACKAGES='emacs awesome zsh biblatex texlive-latex-extra emacs-goodies-el'
BREW_PACKAGES=

cd
HOMEDIR=`pwd`
GITDIR=$HOMEDIR/.dotfiles

esc=""
green() {
    echo "${esc}[32m$1"
    tput sgr0
}

red() {
    echo "${esc}[31m$1"
    tput sgr0
}

plain() {
    echo "${esc}[0m$1"
    tput sgr0
}

if which apt-get &> /dev/null; then
    green "Installing $APT_PACKAGES"
    sudo apt-get install $APT_PACKAGES
elif [ `uname` == "Darwin" ]; then
    if ! which brew &> /dev/null; then
	green 'Installing Homebrew.'
	ruby -e "$(curl -fsSL https://gist.github.com/raw/323731/install_homebrew.rb)"
    fi

    if which brew &> /dev/null -a $BREW_PACKAGES; then
	green "Installing $BREW_PACKAGES"
	brew install $BREW_PACKAGES
    elif [ -z $BREW_PACKAGES ]; then
	plain 'No Brew packages specified. Skipping.'
    else
	red 'Failed to install Homebrew.'
    fi
else
    echo 'No apt-get or Homebrew detected. Skipping package installation.'
fi

if [ ! -d $GITDIR ]; then
    green "Cloning git repository $GITREPO to $GITDIR"
    git clone $GITREPO $GITDIR
else
    green "Dotfile directory exists."
    if [ ! -d $GITDIR/.git ]; then
	red $GITDIR is not a Git repository. Change GITDIR in the script to \
	    choose where to check out the dotfiles repository.
	exit -1
    fi

    green "$GITDIR is a Git repository. Refreshing the repository now..."
    cd $GITDIR
    git pull origin master
fi

cd $GITDIR
for file in `ls -1A`; do
    if [ "$file" != ".git" ]; then
	echo
	green "Creating link for $file"

	if [ -e $HOMEDIR/$file ]; then
	    if [ -L $HOMEDIR/$file ]; then
		red "Removing existing link. (Old link went to $(readlink $HOMEDIR/$file))"
		rm $HOMEDIR/$file
	    else
		bkup=$file.prebootstrap
		red "$HOMEDIR/$file exists. Backing up to $bkup and replacing."
		mv $HOMEDIR/$file $HOME/$bkup
	    fi
	fi

	ln -s $GITDIR/$file $HOMEDIR/
    fi
done