class ViewMailer < ActionMailer::Base
  include AbstractController::Callbacks
  
  helper AvatarHelper
  helper BacktraceHelper
  helper CommitHelper
  helper EmailHelper
  helper EmojiHelper
  helper MarkdownHelper
  helper ReleaseHelper
  helper ScoreCardHelper
  helper StaticChartHelper
  helper TestRunHelper
  helper TicketHelper
  helper UrlHelper
  
  class_attribute :stylesheets
  self.stylesheets = %w{
    core/colors.scss.erb
    core/avatars.scss
    core/scores.scss
    application/emoji.scss
    application/markdown.scss
    application/test_run.scss
    application/releases.scss
    application/pull_requests.scss
    application/follow_up.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_filter { @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
          # !todo: inline SVG images
          # image = Magick::Image::from_blob(svg) { self.format = "svg" }
          # png = image[0].to_blob { self.format = "png" }
          # File.open(File.expand_path("~/Desktop/test.png", "w")) { |f| f.write(png) }
          
          # http://ubuntuforums.org/showthread.php?t=820965&s=e5da4de191aaf858d88085ee67d9ade1&p=5131769#post5131769
          # $ cd your-directory-with-the-svgs/
          # $ for i in *; do rsvg-convert $i -o  echo $i | sed -e 's/svg$/png/'; done
          #
          # brew install librsvg
          # https://gist.github.com/anonymous/d25154daff3e33dd6f7e
          # failed to install gettext
          # http://superuser.com/questions/134679/command-line-application-for-converting-svg-to-png-on-mac-os-x/723031#723031
          
          # Looks like ImageMagic uses RSVG
          # http://stackoverflow.com/questions/24513244/use-librsvg-rsvg-to-convert-svg-images-with-imagemagick
          # → convert -list delegate | grep svg
          #         svg =>          "rsvg-convert" -o "%o" "%i"
          
          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