JezK
Edit File: transfer_encoding.rb
# encoding: utf-8 # frozen_string_literal: true module Mail module Encodings class TransferEncoding NAME = '' PRIORITY = -1 # And encoding's superclass can always transport it since the # class hierarchy is arranged e.g. Base64 < 7bit < 8bit < Binary. def self.can_transport?(enc) enc && enc <= self end # Override in subclasses to indicate that they can encode text # that couldn't be directly transported, e.g. Base64 has 7bit output, # but it can encode binary. def self.can_encode?(enc) can_transport? enc end def self.cost(str) raise "Unimplemented" end def self.compatible_input?(str) true end def self.to_s self::NAME end def self.negotiate(message_encoding, source_encoding, str, allowed_encodings = nil) message_encoding = Encodings.get_encoding(message_encoding) || Encodings.get_encoding('8bit') source_encoding = Encodings.get_encoding(source_encoding) if message_encoding && source_encoding && message_encoding.can_transport?(source_encoding) && source_encoding.compatible_input?(str) source_encoding else renegotiate(message_encoding, source_encoding, str, allowed_encodings) end end def self.renegotiate(message_encoding, source_encoding, str, allowed_encodings = nil) encodings = Encodings.get_all.select do |enc| (allowed_encodings.nil? || allowed_encodings.include?(enc)) && message_encoding.can_transport?(enc) && enc.can_encode?(source_encoding) end lowest_cost(str, encodings) end def self.lowest_cost(str, encodings) best = nil best_cost = nil encodings.each do |enc| # If the current choice cannot be transported safely, give priority # to other choices but allow it to be used as a fallback. this_cost = enc.cost(str) if enc.compatible_input?(str) if !best_cost || (this_cost && this_cost < best_cost) best_cost = this_cost best = enc elsif this_cost == best_cost best = enc if enc::PRIORITY < best::PRIORITY end end best end end end end