resolves asciidoctor#396 add support for :back-cover-image: document …

…attribute

CHANGELOG.adoc

@@ -10,6 +10,7 @@ For a detailed view of what has changed, refer to the {uri-repo}/commits/master[
 * update Font Awesome Solid to 5.15.1
 * use CSS for image size scaling instead of `width` attribute. #382
 * use pygments.rb 2.0.0 in CI
+* add support for `:back-cover-image:` document attribute (#396)
 
 == 1.5.0.alpha.19 (2020-10-21) - @slonopotamus
 

WORKLOG.adoc

@@ -51,7 +51,6 @@
 .Packager
 * HIGH: add NOTICE.adoc to e-book archive
 * HIGH: minimize CSS (and any other assets worth minimizing)
-* HIGH: add back cover if specified
 * MEDIUM: add JavaScript to nav.xhtml to add class for epubReadingSystem to body
 * MEDIUM: option to add nav.xhtml to navigation flow?
 * support subtitle as separate from main title in package metadata

lib/asciidoctor-epub3/converter.rb

@@ -227,8 +227,8 @@ def convert_document node
         # https://idpf.github.io/epub-vocabs/structure/
         landmarks = []
 
-        cover_page = add_cover_page node
-        landmarks << { type: 'cover', href: cover_page.href, title: 'Cover' } unless cover_page.nil?
+        front_cover = add_cover_page node, 'front-cover'
+        landmarks << { type: 'cover', href: front_cover.href, title: 'Front Cover' } unless front_cover.nil?
 
         front_matter_page = add_front_matter_page node
         landmarks << { type: 'frontmatter', href: front_matter_page.href, title: 'Front Matter' } unless front_matter_page.nil?
@@ -253,6 +253,9 @@ def convert_document node
           add_chapter node
         end
 
+        _back_cover = add_cover_page node, 'back-cover'
+        # TODO: add landmark for back cover? But what epub:type?
+
         landmarks << { type: 'bodymatter', href: %(#{get_chapter_name toc_items[0]}.xhtml), title: 'Start of Content' } unless toc_items.empty?
 
         toc_items.each do |item|
@@ -1347,28 +1350,30 @@ def add_theme_assets doc
         nil
       end
 
-      def add_cover_page doc
-        return nil if (image_path = doc.attr 'front-cover-image').nil?
+      def add_cover_page doc, name
+        image_attr_name = %(#{name}-image)
+
+        return nil if (image_path = doc.attr image_attr_name).nil?
 
         imagesdir = (doc.attr 'imagesdir', '.').chomp '/'
         imagesdir = (imagesdir == '.' ? '' : %(#{imagesdir}/))
 
         image_attrs = {}
         if (image_path.include? ':') && image_path =~ ImageMacroRx
-          logger.warn %(deprecated block macro syntax detected in front-cover-image attribute) if image_path.start_with? 'image::'
+          logger.warn %(deprecated block macro syntax detected in :#{attr_name}: attribute) if image_path.start_with? 'image::'
           image_path = %(#{imagesdir}#{$1})
           (::Asciidoctor::AttributeList.new $2).parse_into image_attrs, %w(alt width height) unless $2.empty?
         end
 
-        image_href = %(#{imagesdir}jacket/cover#{::File.extname image_path})
+        image_href = %(#{imagesdir}jacket/#{name}#{::File.extname image_path})
 
         workdir = doc.attr 'docdir'
         workdir = '.' if workdir.nil_or_empty?
 
         begin
           @book.add_item(image_href, content: File.join(workdir, image_path)).cover_image
         rescue => e
-          logger.error %(#{::File.basename doc.attr('docfile')}: error adding front cover image. Make sure that :front-cover-image: attribute points to a valid image file. #{e})
+          logger.error %(#{::File.basename doc.attr('docfile')}: error adding cover image. Make sure that :#{image_attr_name}: attribute points to a valid image file. #{e})
           return nil
         end
 
@@ -1409,7 +1414,7 @@ def add_cover_page doc
 </svg></body>
 </html>).to_ios
 
-        @book.add_ordered_item 'cover.xhtml', content: content, id: 'cover'
+        @book.add_ordered_item %(#{name}.xhtml), content: content, id: name
       end
 
       def get_frontmatter_files doc, workdir

spec/fixtures/back-cover-image/book.adoc

@@ -0,0 +1,5 @@
+= Book with front cover image
+:doctype: book
+:back-cover-image: default-cover.png
+
+Text

spec/image_spec.rb

@@ -49,11 +49,20 @@
 
   it 'adds front cover image' do
     book, = to_epub fixture_file('front-cover-image/book.adoc')
-    cover_image = book.item_by_href 'jacket/cover.png'
+    cover_image = book.item_by_href 'jacket/front-cover.png'
     expect(cover_image).not_to be_nil
-    cover_page = book.item_by_href 'cover.xhtml'
+    cover_page = book.item_by_href 'front-cover.xhtml'
     expect(cover_page).not_to be_nil
-    expect(cover_page.content).to include '<image width="1050" height="1600" xlink:href="jacket/cover.png"/>'
+    expect(cover_page.content).to include '<image width="1050" height="1600" xlink:href="jacket/front-cover.png"/>'
+  end
+
+  it 'adds back cover image' do
+    book, = to_epub fixture_file('back-cover-image/book.adoc')
+    cover_image = book.item_by_href 'jacket/back-cover.png'
+    expect(cover_image).not_to be_nil
+    cover_page = book.item_by_href 'back-cover.xhtml'
+    expect(cover_page).not_to be_nil
+    expect(cover_page.content).to include '<image width="1050" height="1600" xlink:href="jacket/back-cover.png"/>'
   end
 
   it "doesn't crash if cover image points to a directory" do