main() {
    # Use colors, but only if connected to a terminal, and that terminal
    # supports them.
    if which tput >/dev/null 2>&1; then
        ncolors=$(tput colors)
    fi
    if [ -t 1 ] && [ -n "$ncolors" ] && [ "$ncolors" -ge 8 ]; then
      RED="$(tput setaf 1)"
      GREEN="$(tput setaf 2)"
      YELLOW="$(tput setaf 3)"
      BLUE="$(tput setaf 4)"
      BOLD="$(tput bold)"
      NORMAL="$(tput sgr0)"
    else
      RED=""
      GREEN=""
      YELLOW=""
      BLUE=""
      BOLD=""
      NORMAL=""
    fi

    # Only enable exit-on-error after the non-critical colorization stuff,
    # which may fail on systems lacking tput or terminfo
    set -e

    CHECK_ZSH_INSTALLED=$(grep /zsh$ /etc/shells | wc -l)
    if [ ! $CHECK_ZSH_INSTALLED -ge 1 ]; then
      printf "${YELLOW}Zsh is not installed!${NORMAL} Please install zsh first!
  "
      exit
    fi
    unset CHECK_ZSH_INSTALLED

    if [ ! -n "$ZSH" ]; then
      ZSH=~/.oh-my-zsh
    fi

    if [ -d "$ZSH" ]; then
      printf "${YELLOW}You already have Oh My Zsh installed.${NORMAL}
  "
      printf "You'll need to remove $ZSH if you want to re-install.
  "
      exit
    fi

    # Prevent the cloned repository from having insecure permissions. Failing to do
    # so causes compinit() calls to fail with "command not found: compdef" errors
    # for users with insecure umasks (e.g., "002", allowing group writability). Note
    # that this will be ignored under Cygwin by default, as Windows ACLs take
    # precedence over umasks except for filesystems mounted with option "noacl".
    umask g-w,o-w

    printf "${BLUE}Cloning Oh My Zsh...${NORMAL}
  "
    hash git >/dev/null 2>&1 || {
      echo "Error: git is not installed"
      exit 1
    }
    env git clone --depth=1 https://github.com/robbyrussell/oh-my-zsh.git $ZSH || {
      printf "Error: git clone of oh-my-zsh repo failed
  "

      exit 1

    }
  
    # The Windows (MSYS) Git is not compatible with normal use on cygwin
    if [ "$OSTYPE" = cygwin ]; then
      if git --version | grep msysgit > /dev/null; then
        echo "Error: Windows/MSYS Git is not supported on Cygwin"
        echo "Error: Make sure the Cygwin git package is installed and is first on the path"
        exit 1
      fi

    fi

    printf "${BLUE}Looking for an existing zsh config...${NORMAL}
  "
    if [ -f ~/.zshrc ] || [ -h ~/.zshrc ]; then
      printf "${YELLOW}Found ~/.zshrc.${NORMAL} ${GREEN}Backing up to ~/.zshrc.pre-oh-my-zsh${NORMAL}
  ";
      mv ~/.zshrc ~/.zshrc.pre-oh-my-zsh;
    fi

    printf "${BLUE}Using the Oh My Zsh template file and adding it to ~/.zshrc${NORMAL}
  "
    cp $ZSH/templates/zshrc.zsh-template ~/.zshrc
    sed "/^export ZSH=/ c\\
    export ZSH=$ZSH
    " ~/.zshrc > ~/.zshrc-omztemp
    mv -f ~/.zshrc-omztemp ~/.zshrc

    printf "${BLUE}Copying your current PATH and adding it to the end of ~/.zshrc for you.${NORMAL}
  "
    sed "/export PATH=/ c\\
    export PATH=\"$PATH\"
    " ~/.zshrc > ~/.zshrc-omztemp
    mv -f ~/.zshrc-omztemp ~/.zshrc

    # If this user's login shell is not already "zsh", attempt to switch.
    TEST_CURRENT_SHELL=$(expr "$SHELL" : '.*/\(.*\)')
    if [ "$TEST_CURRENT_SHELL" != "zsh" ]; then
      # If this platform provides a "chsh" command (not Cygwin), do it, man!
      if hash chsh >/dev/null 2>&1; then
        printf "${BLUE}Time to change your default shell to zsh!${NORMAL}
  "
        chsh -s $(grep /zsh$ /etc/shells | tail -1)
      # Else, suggest the user do so manually.
      else
        printf "I can't change your shell automatically because this system does not have chsh.
  "
        printf "${BLUE}Please manually change your default shell to zsh!${NORMAL}
  "
      fi

    fi

    printf "${GREEN}"
    echo '         __                                     __   '
    echo '  ____  / /_     ____ ___  __  __   ____  _____/ /_  '
    echo ' / __ \/ __ \   / __ `__ \/ / / /  /_  / / ___/ __ \ '
    echo '/ /_/ / / / /  / / / / / / /_/ /    / /_(__  ) / / / '
    echo '\____/_/ /_/  /_/ /_/ /_/\__, /    /___/____/_/ /_/  '
    echo '                        /____/                       ....is now installed!'
    echo ''
    echo ''
    echo 'Please look over the ~/.zshrc file to select plugins, themes, and options.'
    echo ''
    echo 'p.s. Follow us at https://twitter.com/ohmyzsh.'
    echo ''
    echo 'p.p.s. Get stickers and t-shirts at http://shop.planetargon.com.'
    echo ''
    printf "${NORMAL}"
    env zsh

  }
  
  main