# Copyright (C) 2011 RightScale, Inc, All Rights Reserved Worldwide.
#
# THIS PROGRAM IS CONFIDENTIAL AND PROPRIETARY TO RIGHTSCALE
# AND CONSTITUTES A VALUABLE TRADE SECRET. Any unauthorized use,
# reproduction, modification, or disclosure of this program is
# strictly prohibited. Any use of this program by an authorized
# licensee is strictly subject to the terms and conditions,
# including confidentiality obligations, set forth in the applicable
# License Agreement between RightScale.com, Inc. and
# the licensee

module RightConf

  class BrewInstaller

    include ProgressReporter

    # Check whether brew is already installed and install it if not
    #
    # === Return
    # true:: Always return true
    def self.check_and_install
      installed = Command.execute('brew', '--version').success? 
      return true if installed
      new.install
    end

    # Actually install brew
    #
    # === Return
    # true:: Always return true
    def install
      report_check('Installing Homebrew')

      chmods = %w( . bin etc include lib lib/pkgconfig Library sbin share var share/locale share/man
             share/man/man1 share/man/man2 share/man/man3 share/man/man4
             share/man/man5 share/man/man6 share/man/man7 share/man/man8
             share/info share/doc share/aclocal ).
             map{ |d| "/usr/local/#{d}" }.
             select{ |d| File.directory? d and not File.writable? d }
      chgrps = chmods.reject{ |d| File.stat(d).grpowned? }

      if File.directory?('/usr/local')
        Command.sudo('/bin/chmod', 'g+w', *chmods) unless chmods.empty?
        # all admin users are in staff
        Command.sudo('/usr/bin/chgrp', 'staff', *chgrps) unless chgrps.empty?
      else
        Command.sudo('/bin/mkdir', '/usr/local')
        Command.sudo('/bin/chmod', 'g+w', '/usr/local')
        # the group is set to wheel by default for some reason
        Command.sudo('/usr/bin/chgrp', 'staff', '/usr/local')
      end

      Dir.chdir('/usr/local') do
        # -m to stop tar erroring out if it can't modify the mtime for root owned directories
        # pipefail to cause the exit status from curl to propogate if it fails
        system("/bin/bash -o pipefail -c '/usr/bin/curl -sSfL https://github.com/mxcl/homebrew/tarball/master | /usr/bin/tar xz -m --strip 1'")
      end

      report_success

      unless chmods.empty?
        report("The following directories had to be made group writable: #{chmods.join(', ')}")
      end
      unless chgrps.empty?
        report("The following directories had their group set to staff: #{chgrps.join(', ')}")
      end
      unless ENV['PATH'].split(':').include? '/usr/local/bin'
        report('/usr/local/bin is not in your PATH.') 
      end
    end

  end
end