class Chef::Cookbook::GemInstaller

def initialize(cookbook_collection, events)
  @cookbook_collection = cookbook_collection
  @events = events
end

def install
  cookbook_gems = Hash.new { |h, k| h[k] = [] }
  cookbook_collection.each_value do |cookbook_version|
    cookbook_version.metadata.gems.each do |args|
      if cookbook_gems[args.first].last.is_a?(Hash)
        args << {} unless args.last.is_a?(Hash)
        args.last.merge!(cookbook_gems[args.first].pop) do |key, v1, v2|
          raise Chef::Exceptions::GemRequirementConflict.new(args.first, key, v1, v2) if v1 != v2
          v2
        end
      end
      cookbook_gems[args.first] += args[1..]
    end
  end
  events.cookbook_gem_start(cookbook_gems)
  unless cookbook_gems.empty?
    begin
      Dir.mktmpdir("chef-gem-bundle") do |dir|
        File.open("#{dir}/Gemfile", "w+") do |tf|
          Array(Chef::Config[:rubygems_url] || "https://rubygems.org").each do |s|
            tf.puts "source '#{s}'"
          end
          cookbook_gems.each do |gem_name, args|
            tf.puts "gem(*#{([gem_name] + args).inspect})"
          end
          tf.close
          Chef::Log.trace("generated Gemfile contents:")
          Chef::Log.trace(IO.read(tf.path))
          # Skip installation only if Chef::Config[:skip_gem_metadata_installation] option is true
          unless Chef::Config[:skip_gem_metadata_installation]
            # Add additional options to bundle install
            cmd = [ "bundle", "install", Chef::Config[:gem_installer_bundler_options] ]
            env = {
              "PATH" => path_with_prepended_ruby_bin,
              "BUNDLE_SILENCE_ROOT_WARNING" => "1",
            }
            so = shell_out!(cmd, cwd: dir, env: env)
            Chef::Log.info(so.stdout)
          end
        end
      end
      Gem.clear_paths
    rescue Exception => e
      events.cookbook_gem_failed(e)
      raise
    end
  end
  events.cookbook_gem_finished
end

def path_with_prepended_ruby_bin
  env_path = ENV["PATH"].dup || ""
  existing_paths = env_path.split(File::PATH_SEPARATOR)
  existing_paths.unshift(RbConfig::CONFIG["bindir"])
  env_path = existing_paths.join(File::PATH_SEPARATOR)
  env_path.encode("utf-8", invalid: :replace, undef: :replace)
end