class Bundler::Installer

def self.install(root, definition, options = {})
  installer = new(root, definition)
  installer.run(options)
  installer
end

def generate_bundler_executable_stubs(spec)
  bin_path = Bundler.bin_path
  template = File.read(File.expand_path('../templates/Executable', __FILE__))
  relative_gemfile_path = Bundler.default_gemfile.relative_path_from(bin_path)
  spec.executables.each do |executable|
    next if executable == "bundle"
    File.open "#{bin_path}/#{executable}", 'w', 0755 do |f|
      f.puts ERB.new(template, nil, '-').result(binding)
    end
  end
end

def run(options)
  if dependencies.empty?
    Bundler.ui.warn "The Gemfile specifies no dependencies"
    return
  end
  if Bundler.root.join("Gemfile.lock").exist? && !options["update"]
    begin
      missing_specs = Definition.build(Bundler.default_gemfile, Bundler.root.join("Gemfile.lock"), nil).missing_specs
      local = true unless missing_specs.any?
    rescue BundlerError
    end
  end
  # Since we are installing, we can resolve the definition
  # using remote specs
  unless local
    options["local"] ?
      @definition.resolve_with_cache! :
      @definition.resolve_remotely!
  end
  # Ensure that BUNDLE_PATH exists
  Bundler.mkdir_p(Bundler.bundle_path) unless File.exist?(Bundler.bundle_path)
  # Must install gems in the order that the resolver provides
  # as dependencies might actually affect the installation of
  # the gem.
  specs.each do |spec|
    spec.source.fetch(spec) if spec.source.respond_to?(:fetch)
    # unless requested_specs.include?(spec)
    #   Bundler.ui.debug "  * Not in requested group; skipping."
    #   next
    # end
    begin
      old_args = Gem::Command.build_args
      Gem::Command.build_args = [Bundler.settings["build.#{spec.name}"]]
      spec.source.install(spec)
    ensure
      Gem::Command.build_args = old_args
    end
    Bundler.ui.info ""
    generate_bundler_executable_stubs(spec) if Bundler.settings[:bin]
    FileUtils.rm_rf(Bundler.tmp)
  end
  lock
end