require 'uri/common' # A chunk is a pattern of text that can be protected # and interrogated by a renderer. Each Chunk class has a # +pattern+ that states what sort of text it matches. # Chunks are initalized by passing in the result of a # match by its pattern. module Chunk class Abstract # automatically construct the array of derivatives of Chunk::Abstract @derivatives = [] class << self attr_reader :derivatives end def self::inherited( klass ) Abstract::derivatives << klass end # the class name part of the mask strings def self.mask_string self.to_s.delete(':').downcase end # a regexp that matches all chunk_types masks def Abstract::mask_re(chunk_types) chunk_classes = chunk_types.map{|klass| klass.mask_string}.join("|") /chunk(-?\d+)(#{chunk_classes})chunk/ end attr_reader :text, :unmask_text, :unmask_mode def initialize(match_data, content) @text = match_data[0] @content = content @unmask_mode = :normal end # Find all the chunks of the given type in content # Each time the pattern is matched, create a new # chunk for it, and replace the occurance of the chunk # in this content with its mask. def self.apply_to(content) content.gsub!( self.pattern ) do |match| new_chunk = self.new($~, content) content.add_chunk(new_chunk) new_chunk.mask end end # should contain only [a-z0-9] def mask @mask ||= "chunk#{self.object_id}#{self.class.mask_string}chunk" end def unmask @content.sub!(mask, @unmask_text) end def rendered? @unmask_mode == :normal end def escaped? @unmask_mode == :escape end def revert @content.sub!(mask, @text) # unregister @content.delete_chunk(self) end end end