houston/houston-core

class ViewMailer < ActionMailer::Base
  include AbstractController::Callbacks

  helper AvatarHelper
  helper EmailHelper
  helper EmojiHelper
  helper MarkdownHelper
  helper ScoreCardHelper
  helper UrlHelper
  helper OembedHelper

  class_attribute :stylesheets
  self.stylesheets = %w{
    houston/core/colors.scss.erb
    houston/core/avatars.scss
    houston/core/scores.scss
    houston/application/emoji.scss
    houston/application/markdown.scss
  }

  helper_method :can?, :cannot?, :current_ability, :stylesheets
  delegate :can?, :cannot?, to: :current_ability
  delegate :stylesheets, to: "self.class"

  # c.f. https://github.com/ryanb/cancan/blob/1.6.7/lib/cancan/controller_additions.rb#L348-L350
  def current_ability
    @current_ability ||= ::Ability.new(User.new) # Treat email recipients as Guests, not Customers
  end


  before_action { @for_email = true }


protected


  def mail(options={})
    options[:from] = format_email_addresses(options[:from]) if options.key?(:from)
    options[:to] = format_email_addresses(options[:to]).uniq if options.key?(:to)
    options[:cc] = format_email_addresses(options[:cc]).uniq if options.key?(:cc)
    options[:bcc] = format_email_addresses(options[:bcc]).uniq if options.key?(:bcc)

    # Don't CC anyone whose already being mailed
    options[:cc] -= options[:to] if options[:to] && options[:cc]

    return if Array(options[:to]).none? and Array(options[:cc]).none?

    if block_given?
      super
    else
      template = options.delete(:template)
      super(options) do |format|
        format.html do
          html = render_to_string(template: template, layout: "email")
          begin
            html = Premailer.new(html, with_html_string: true).to_inline_css
          rescue SystemStackError
            # If the email is large enough, Hpricot will simply choke on it
            # and raise a SystemStackError. In that eventuality, let's just
            # deliver an unstyled message.
            #
            # Note: Premailer 2.0 will drop Hpricot, but that's not going to
            # out for a while...
          end

          html
        end
      end
    end
  end


  def format_email_addresses(recipients)
    Array.wrap(recipients).map &method(:format_email_address)
  end


  def format_email_address(recipient)
    if recipient.respond_to?(:name) && recipient.respond_to?(:email)
      Mail::Address.new.tap do |email|
        email.display_name = recipient.name
        email.address = recipient.email
      end.to_s
    else
      recipient
    end
  end


end