feature: initial implementation of EPUB generation

Gemfile

@@ -26,6 +26,7 @@ gem 'puma', '~> 5.0'
 gem 'sidekiq'
 
 # Other stuff
+gem 'gepub'
 gem 'marcel'
 
 # Windows does not include zoneinfo files, so bundle the tzinfo-data gem

Gemfile.lock

@@ -120,6 +120,9 @@ GEM
       faraday-net_http (>= 2.0, < 3.2)
     faraday-net_http (3.1.0)
       net-http
+    gepub (1.0.15)
+      nokogiri (>= 1.8.2, < 2.0)
+      rubyzip (> 1.1.1, < 2.4)
     globalid (1.2.1)
       activesupport (>= 6.1)
     hashie (5.0.0)
@@ -305,6 +308,7 @@ DEPENDENCIES
   debug
   elasticsearch-model
   fancy_searchable!
+  gepub
   kaminari
   marcel
   model-msearch

app/controllers/chapters_controller.rb

@@ -6,27 +6,6 @@ class ChaptersController < ApplicationController
     @story = Story.find(params[:story_id])
     @chapter = @story.chapters.find_by(number: params[:id])
 
-    @rendered_html = render_story
-  end
-
-  private
-
-  def render_story
-    body = @chapter.body
-    body.lstrip!
-    body = body.split "\n"
-
-    # This is fucking bad, this gets rid of the redundant title - this should be fixed upstairs,
-    # in the actual generation of the Markdown.
-    if body.length >= 2 && body[0] == @chapter.title && !body[1].empty? && body[1][0] == '='
-      body = body[2..]
-    end
-
-    markdown.render body.join("\n")
-  end
-
-  def markdown
-    @@markdown ||=
-      Redcarpet::Markdown.new(Redcarpet::Render::HTML, autolink: true, tables: true)
+    @rendered_html = StoryRenderer.render_chapter(@chapter)
   end
 end

app/lib/ebook/epub_generator.rb

@@ -0,0 +1,43 @@
+require 'gepub'
+
+TEMPLATE_DIRECTORY = Rails.root.join('app/lib/ebook')
+
+class Ebook::EpubGenerator
+  include ActionView::Helpers::TagHelper
+
+  def initialize(story)
+    @story = story
+  end
+
+  def generate
+    book = GEPUB::Book.new
+    book.add_title @story.title, title_type: GEPUB::TITLE_TYPE::MAIN, lang: :en, display_seq: 1
+    book.add_creator @story.author.name
+    book.add_item 'styles.css', content: TEMPLATE_DIRECTORY.join('files/styles.css').open
+
+    book.ordered do
+      book.add_item('CoverPage.html', content: generate_cover_page).landmark(type: 'cover', title: 'Cover Page')
+      @story.chapters.each do |chapter|
+        book.add_item("Chapter#{chapter.number}.html", content: generate_chapter(chapter))
+            .toc_text("Chapter #{chapter.number} - #{chapter.title}")
+            .landmark(type: 'bodymatter', title: chapter.title)
+      end
+    end
+
+    book
+  end
+
+  #private
+
+  def render_template(name, context)
+    Slim::Template.new(TEMPLATE_DIRECTORY.join("templates/#{name}.html.slim")).render(context)
+  end
+
+  def generate_cover_page
+    StringIO.new render_template('cover', @story)
+  end
+
+  def generate_chapter(chapter)
+    StringIO.new render_template('chapter', chapter)
+  end
+end

app/lib/ebook/files/styles.css

@@ -0,0 +1,72 @@
+.double {
+    margin-top: 1em;
+}
+.indented {
+    text-indent: 3em;
+}
+.i {
+    font-style: italic;
+}
+.u {
+    text-decoration: underline;
+}
+.b {
+    font-weight: bold;
+}
+.c {
+    text-align: center;
+}
+.s {
+    text-decoration: line-through;
+}
+img.emoticon {
+    margin: 0;
+    padding: 0;
+    border: 0;
+    height: 1em;
+}
+hr {
+    margin-top: 12px;
+}
+blockquote {
+    padding: 5px 10px;
+    margin: 10px;
+    border-left: 5px solid #aaa;
+    background: #eee;
+}
+.authors-note,
+.preface {
+    border-top: 3px double #333;
+    border-bottom: 3px double #333;
+}
+.afterward {
+    border-top: 3px double #333;
+}
+h1 {
+    font-size: 1.9em;
+    margin: 0.8em 0;
+}
+h2 {
+    font-size: 1.3em;
+    margin: 0.5em 0;
+}
+h3 {
+    font-size: 0.625em;
+    margin: 0;
+}
+.authors-note,
+.preface,
+.afterward {
+    background: none;
+    border-left: none;
+    padding: 4px 0;
+}
+.authors-note h1,
+.authors-note h2,
+.preface h1,
+.preface h2,
+.afterward h1,
+.afterward h2 {
+    margin: 0.5em 0;
+    font-size: 1.3em;
+}

app/lib/ebook/templates/chapter.html.slim

@@ -0,0 +1,10 @@
+doctype xml
+html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"
+  head
+    meta http-equiv="Content-Type" content="text/html; charset=UTF-8"
+    link rel="stylesheet" href="styles.css"
+    title= title
+  body
+    h1= title
+    .calibre2#content
+      == StoryRenderer.render_chapter(self)

app/lib/ebook/templates/cover.html.slim

@@ -0,0 +1,33 @@
+doctype xml
+html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"
+  head
+    meta http-equiv="Content-Type" content="text/html; charset=UTF-8"
+    link rel="stylesheet" href="styles.css"
+    title Cover
+  body
+    table style="width: 100%; height: 100%;"
+      tr
+        td
+          h1= title
+          p
+            b by #{author.name}
+          hr
+          p
+            | Rating: #{content_rating}
+            br
+            | Tags: #{tags.pluck(:name).join(', ')}
+            br
+            | Length: #{num_words}
+          hr
+    table.desc
+      tr style="height: 100%;" valign="top"
+        td
+          p.double= short_description
+          == description_html
+      tr.bottom
+        td
+          hr
+          p
+            | Published #{date_published}
+            br
+            | Last updated #{date_updated}