agenda-libre-ruby/app/mailers/event_mailer.rb

class EventMailer < ActionMailer::Base
  def create(event)
    @event = event

    mail 'Message-ID' => "<event-#{event.id}@#{ActionMailer::Base.default_url_options[:host]}>",
      to: event.contact,
      subject: t('event_mailer.create.subject', subject: event.title)
  end

  def accept(event, current_user)
    @event = event
    @current_user = current_user

    mail 'In-Reply-To' => "<event-#{event.id}@#{ActionMailer::Base.default_url_options[:host]}>",
      to: event.contact,
      subject: t('event_mailer.accept.subject', subject: event.title)
  end

  def destroy(event, current_user, reason)
    @event = event
    @current_user = current_user
    @reason = reason

    mail 'In-Reply-To' => "<event-#{event.id}@#{ActionMailer::Base.default_url_options[:host]}>",
      to: event.contact,
      subject: t('event_mailer.destroy.subject', subject: event.title)
  end
end