# Copyright (c) 2008-16 Peter H. Boling of RailsBling.com
# Released under the MIT license

module SanitizeEmail
  # Determines whether to sanitize the headers of an email,
  #   and does so when appropriate.
  class Bleach
    extend SanitizeEmail::Deprecation
    attr_accessor :overridden_addresses # TODO: Just a stub, not implemented

    def initialize(*args)
      deprecation_message = <<EOS
SanitizeEmail:
  Passing arguments to SanitizeEmail::Bleach.new is deprecated.
  SanitizeEmail::Bleach.new now takes no arguments.
EOS
      if !args.empty?
        self.class.deprecation_warning_message(deprecation_message)
      end
    end

    # If all recipient addresses are white-listed the field is left alone.
    def self.delivering_email(message)
      if self.sanitize_engaged?(message)
        SanitizeEmail::MailHeaderTools.
          add_original_addresses_as_headers(message)
        SanitizeEmail::MailHeaderTools.
          prepend_custom_subject(message)

        overridden = SanitizeEmail::OverriddenAddresses.new(message)

        message.to = overridden.overridden_to
        message.cc = overridden.overridden_cc
        message.bcc = overridden.overridden_bcc
      end
    end

    # Will be called by the Hook to determine if an override should occur
    # There are three ways SanitizeEmail can be turned on;
    #   in order of precedence they are:
    #
    # 1. SanitizeEmail.force_sanitize = true # by default it is nil
    #   Only useful for local context.
    #   Inside a method where you will be sending an email, set
    #
    #     SanitizeEmail.force_sanitize = true
    #
    #   just prior to delivering it.  Also useful in the console.
    #
    # 2. If SanitizeEmail seems to not be sanitizing,
    #     you have probably not registered the interceptor.
    #   SanitizeEmail tries to do this for you.
    #   *Note*: If you are working in an environment that has
    #           a Mail or Mailer class that uses the register_interceptor API,
    #           the interceptor will already have been registered.
    #   The gem will probably have already done this for you,
    #   but some really old versions of Rails may need you to do this manually:
    #
    #     Mail.register_interceptor(SanitizeEmail::Bleach)
    #
    #   Once registered, SanitizeEmail needs to be engaged:
    #
    #     # in config/initializers/sanitize_email.rb
    #     SanitizeEmail::Config.configure {|config| config[:engage] = true }
    #
    # 3. SanitizeEmail::Config.configure do |config|
    #      config[:activation_proc] = Proc.new { true }
    #    end
    #
    #   If you don't need to compute anything,
    #     then don't use the Proc, go with the previous option.
    #
    # Note: Number 1 is the method used by the SanitizeEmail.sanitary block
    # Note: Number 2 You may need to setup your own register_interceptor
    #
    # If installed but not configured, sanitize_email DOES NOTHING.
    # Until configured the defaults leave it turned off.
    def self.sanitize_engaged?(message)

      # Don't sanitize the message if it will not be delivered
      return false unless message.perform_deliveries

      # Has it been forced via the force_sanitize mattr?
      forced = SanitizeEmail.force_sanitize
      return forced unless forced.nil?

      # Is this particular instance of Bleach engaged
      engaged = SanitizeEmail::Config.config[:engage]
      return engaged unless engaged.nil?

      # Should we sanitize due to the activation_proc?
      return SanitizeEmail.activate?(message)

    end

  end # end Class Bleach
end # end Module SanitizeEmail