manifest.rb in epub-parser-0.0.3

- old
+ new

@@ -1,6 +1,7 @@
 require 'enumerabler'
+require 'epub/constants'
 
 module EPUB
   module Publication
     class Package
       class Manifest
@@ -22,21 +23,57 @@
 
         def nav
           navs.first
         end
 
+        def cover_image
+          items.selector {|i| i.properties.include? 'cover-image'}.first
+        end
+
         def [](item_id)
           items.selector {|item| item.id == item_id}.first
         end
 
         class Item
           attr_accessor :manifest,
-                        :id, :href, :media_type, :fallback, :properties, :media_overlay
+                        :id, :href, :media_type, :fallback, :properties, :media_overlay,
+                        :iri
 
-          alias path href
+          # To do: Handle circular fallback chain
+          def fallback_chain
+            return @fallback_chain if @fallback_chain
+            @fallback_chain = traverse_fallback_chain([])
+          end
 
-          def to_s
-            href.to_s
+          def read
+            open(iri) {|file| file.read}
+          end
+
+          # To do: Handle circular fallback chain
+          def use_fallback_chain(options = {})
+            supported = EPUB::MediaType::CORE
+            if ad = options[:supported]
+              supported = supported | (ad.respond_to?(:to_ary) ? ad : [ad])
+            end
+            if del = options[:not_supported]
+              supported = supported - (del.respond_to?(:to_ary) ? del : [del])
+            end
+
+            if supported.include? media_type
+              yield self
+            elsif fallback
+              fallback.use_fallback_chain(options) {|fallbacked| yield fallbacked}
+            else
+              raise EPUB::MediaType::NotSupportedError
+            end
+          end
+
+          protected
+
+          def traverse_fallback_chain(chain)
+            chain << self
+            return chain unless fallback
+            fallback.traverse_fallback_chain(chain)
           end
         end
       end
     end
   end