Add support for playgrounds with multiple pages

Gemfile

@@ -8,6 +8,7 @@ gem "mocha-on-bacon"
 gem "prettybacon"
 gem "fakefs"
 gem "rubocop", "~> 0.41.2", require: false
+gem "nokogiri"
 
 require "pp" # https://github.com/defunkt/fakefs/issues/99
 gemspec

Gemfile.lock

@@ -39,16 +39,21 @@ GEM
     lumberjack (1.0.10)
     metaclass (0.0.4)
     method_source (0.8.2)
+    mini_portile2 (2.1.0)
     mocha (1.1.0)
       metaclass (~> 0.0.1)
     mocha-on-bacon (0.2.2)
       mocha (>= 0.13.0)
     nenv (0.3.0)
+    nokogiri (1.6.8)
+      mini_portile2 (~> 2.1.0)
+      pkg-config (~> 1.1.7)
     notiffany (0.1.0)
       nenv (~> 0.1)
       shellany (~> 0.0)
     parser (2.3.1.2)
       ast (~> 2.2)
+    pkg-config (1.1.7)
     plist (3.2.0)
     powerpack (0.1.1)
     prettybacon (0.0.2)
@@ -96,6 +101,7 @@ DEPENDENCIES
   guard-rspec
   mocha
   mocha-on-bacon
+  nokogiri
   playgroundbook!
   prettybacon
   rake

README.md

@@ -55,61 +55,19 @@ Each chapter needs to have a corresponding playground; so `Chapter 1` requires t
 
 Only the link to the term must be URL encoded. For example, the term "reuse identifier" would be defined in the yaml as `reuse identifier` but linked to as `glossary://reuse%20identifier`.  
 
-Each chapter needs to be in the following format:
-
-```swift
-// This is the preamble that is shared among all the pages within this chapter.
-
-public var str = "Hi!"
-
-public func sharedFunc() {
-  print("This should be accessible to all pages.")
-}
-
-//// Page 1
-
-str = "Yo, it's page 1."
-sharedFunc()
-
-//// Page 2
-
-sharedFunc()
-str = "Page 2 awww yeah."
-```
-
-Pages are divided by lines beginning with a quadruple slash, followed by that pages name.
+Each page in a chapter's `.playground` will be a separate page in the `.playgroundbook` and it's `Source`. The contents of the `Source` and `Resource` folders for each chapter and each page are copied.  
 
 ### Limitations of Book Rendering
 
+Playground books support a rich set of awesome features to make learning how to code really easy, and this tool only scratches the surface. Read over the [Playground Book reference](https://developer.apple.com/library/content/documentation/Xcode/Conceptual/swift_playgrounds_doc_format/) to see all the available options. If you have suggestions, please open an issue :+1:
+=======
 The preamble (anything about the first `////` page) is put in its own file. That means declarations there need to be `public` to be visible within individual pages (even though when you're writing, everything is in one file). Additionally, the preamble is at the top-level and can't contain expressions. This would cause a compiler error in the Swift Playrounds iPad app:
 
 ```swift
 public let layout = UICollectionViewFlowLayout()
 layout.itemSize = CGSize(width: 20, height: 20)
 ```
 
-Instead, you have to wrap it in a closure, like this:
-
-```swift
-public var layout: UICollectionViewFlowLayout = {
-    let layout = UICollectionViewFlowLayout()
-    layout.itemSize = CGSize(width: 20, height: 20)
-    return layout
-}()
-```
-
-It's awkward; if you have suggestions, open an issue :+1:
-
-Sharing resources is only available book-wide and not specific to chapters. Sharing code outside the preamble isn't supported yet.
-
-#### Using Swift Package Manager Dependencies
-
-If you place a `Package.swift` file next to your playgroundbook manifest used for rendering a book and run `swift package fetch` to fetch the corresponding sources into `Packages/`, these will be copied into the playground book's top-level `Sources` when building and available in the finished book.
-These source files will also be copied into the original playground for each chapter to make these available for use in Xcode.
-Please note that this will work best with SPM packages containing pure Swift.
-
-Playground books support a rich set of awesome features to make learning how to code really easy, and this tool uses almost none of them. It sacrifices this experience for the sake of being able to easily write the books on your Mac.
-
 ### Creating a Playground from markdown
 
 Maybe you want to do something for a website, or a git repo first, and then generate your Playground? Well in those cases your source of truth is the markdown document. For that case, we have `playgroundbook wrapper`.

lib/renderer/chapter_collator.rb

@@ -1,8 +1,10 @@
 require "plist"
+require "fileutils"
 require "renderer/page_writer"
 
 module Playgroundbook
   SharedSourcesDirectoryName = "Sources".freeze
+  SharedResourcesDirectoryName = "Resources".freeze
   PreambleFileName = "Preamble.swift".freeze
 
   class ChapterCollator
@@ -26,12 +28,17 @@ def collate(chapter, parsed_chapter, imports)
             page_contents = parsed_chapter[:page_contents][index]
             page_dir_name = parsed_chapter[:page_dir_names][index]
 
-            @page_writer.write_page(page_name, page_dir_name, imports, page_contents, chapter)
+            page_source_names = parsed_chapter[:page_source_names][index]
+            page_resource_names = parsed_chapter[:page_resource_names][index]
+
+            @page_writer.write_page(page_name, page_dir_name, imports, page_contents, page_source_names, page_resource_names, chapter)
           end
         end
 
         write_chapter_manifest(chapter_name, parsed_chapter[:page_dir_names])
         write_preamble(parsed_chapter[:preamble])
+        copy_sources(parsed_chapter[:source_names])
+        copy_resources(parsed_chapter[:resource_names])
       end
     end
 
@@ -56,5 +63,21 @@ def write_preamble(preamble)
         end
       end
     end
+
+    def copy_sources(source_names)
+      Dir.mkdir(SharedSourcesDirectoryName) unless Dir.exist?(SharedSourcesDirectoryName)
+
+      source_names.each do |source|
+        FileUtils.cp("../../../../#{source}", SharedSourcesDirectoryName)
+      end
+    end
+
+    def copy_resources(resource_names)
+      Dir.mkdir(SharedResourcesDirectoryName) unless Dir.exist?(SharedResourcesDirectoryName)
+
+      resource_names.each do |resource|
+        FileUtils.cp("../../../../#{resource}", SharedResourcesDirectoryName)
+      end
+    end
   end
 end

lib/renderer/page_parser.rb

@@ -1,6 +1,6 @@
 module Playgroundbook
   class PageParser
-    def parse_chapter_pages(chapter_contents)
+    def parse_chapter_pages(chapter_contents, source_names, resource_names)
       # Looks for //// PageName separators.
       page_names = chapter_contents.scan(/\/\/\/\/.*$/).map { |p| p.gsub("////", "").strip }
       page_dir_names = page_names.map { |p| "#{p}.playgroundpage" }
@@ -13,7 +13,29 @@ def parse_chapter_pages(chapter_contents)
         page_dir_names: page_dir_names,
         page_names: page_names,
         page_contents: page_contents,
-        preamble: preamble
+        preamble: preamble,
+        page_source_names: [[]] * page_names.count,   # TODO: Be less hacky
+        page_resource_names: [[]] * page_names.count, # TODO: Be less hacky
+        source_names: source_names,
+        resource_names: resource_names
+      }
+    end
+
+    def parse_chapter_xcplaygroundpages(pages_data, source_names, resource_names)
+      page_dir_names = pages_data.map { |p| "#{p[:name]}.playgroundpage" }
+      page_names = pages_data.map { |p| "#{p[:name]}" }
+      page_contents = pages_data.map { |p| "#{p[:contents]}" }
+      page_source_names = pages_data.map { |p| p[:sources] }
+      page_resource_names = pages_data.map { |p| p[:resources] }
+
+      {
+        page_dir_names: page_dir_names,
+        page_names: page_names,
+        page_contents: page_contents,
+        page_source_names: page_source_names,
+        page_resource_names: page_resource_names,
+        source_names: source_names,
+        resource_names: resource_names
       }
     end
   end

lib/renderer/page_writer.rb

@@ -8,7 +8,7 @@ def initialize(page_processor = PageProcessor.new, ui = Cork::Board.new)
       @ui = ui
     end
 
-    def write_page(page_name, page_dir_name, imports, page_contents, chapter_info={})
+    def write_page(page_name, page_dir_name, imports, page_contents, page_sources, page_resources, chapter_info={})
       Dir.mkdir(page_dir_name) unless Dir.exist?(page_dir_name)
       contents_with_import = "//#-hidden-code\n"
       contents_with_import += imports.map { |i| "import #{i}" }.join("\n") + "\n"
@@ -29,6 +29,25 @@ def write_page(page_name, page_dir_name, imports, page_contents, chapter_info={}
             "ContentVersion" => "1.0"
           }.to_plist)
         end
+
+        copy_page_sources(page_sources)
+        copy_page_resources(page_resources)
+      end
+    end
+
+    def copy_page_sources(source_names)
+      Dir.mkdir(SharedSourcesDirectoryName) unless Dir.exist?(SharedSourcesDirectoryName)
+
+      source_names.each do |source|
+        FileUtils.cp("../../../../../../#{source}", SharedSourcesDirectoryName)
+      end
+    end
+
+    def copy_page_resources(resource_names)
+      Dir.mkdir(SharedResourcesDirectoryName) unless Dir.exist?(SharedResourcesDirectoryName)
+
+      resource_names.each do |resource|
+        FileUtils.cp("../../../../../../#{resource}", SharedResourcesDirectoryName)
       end
     end
   end

lib/renderer/playgroundbook_renderer.rb

@@ -2,6 +2,7 @@
 require "pathname"
 require "yaml"
 require "fileutils"
+require "nokogiri"
 require "renderer/contents_manifest_generator"
 require "renderer/chapter_collator"
 require "renderer/page_parser"
@@ -39,17 +40,36 @@ def render
 
       book = yaml_contents
       book_dir_name = "#{book['name']}.playgroundbook"
-      book_chapter_contents = []
+      parsed_chapters = []
       # TODO: Validate YAML contents?
       begin
-        book_chapter_contents = book["chapters"].map do |chapter|
-          File.read("#{chapter['name']}.playground/Contents.swift")
+        parsed_chapters = book["chapters"].map do |chapter|
+          source_names = Dir["#{chapter['name']}.playground/Sources/*.swift"]
+          resource_names = Dir["#{chapter['name']}.playground/Resources/*"]
+          single_page_file = "#{chapter['name']}.playground/Contents.swift"
+          if File.exist?(single_page_file)
+            c = File.read(single_page_file)
+            page_parser.parse_chapter_pages(c, source_names, resource_names)
+          elsif !Dir.glob("#{chapter['name']}.playground/Pages/*.xcplaygroundpage").empty?
+            toc = Nokogiri::XML(File.read("#{chapter['name']}.playground/contents.xcplayground"))
+            page_names = toc.xpath("//page").map { |p| p["name"] }
+            pages_data = page_names.map do |p|
+              {
+                name: p,
+                contents: File.read("#{chapter['name']}.playground/Pages/#{p}.xcplaygroundpage/Contents.swift"),
+                sources: Dir["#{chapter['name']}.playground/Pages/#{p}.xcplaygroundpage/Sources/*.swift"],
+                resources: Dir["#{chapter['name']}.playground/Pages/#{p}.xcplaygroundpage/Resources/*"]
+              }
+            end
+            page_parser.parse_chapter_xcplaygroundpages(pages_data, source_names, resource_names)
+          else
+            raise "Missing valid playground for #{chapter['name']}."
+          end
         end
       rescue => e
-        ui.puts "Failed to open playground Contents.swift file."
+        ui.puts "Failed to open and parse playground chapter."
         raise e
       end
-      parsed_chapters = book_chapter_contents.map { |c| page_parser.parse_chapter_pages(c) }
 
       book["chapters"].map do |chapter|
         Dir.glob("Packages/**/Sources/*.swift").each do |file|

spec/renderer/chapter_collator_spec.rb

@@ -6,7 +6,7 @@ module Playgroundbook
     let(:collator) { ChapterCollator.new(page_writer, test_ui) }
     let(:page_writer) { double(PageWriter) }
     let(:test_ui) { Cork::Board.new(silent: true) }
-    let(:parsed_chapter) { PageParser.new.parse_chapter_pages(test_chapter_contents) }
+    let(:parsed_chapter) { PageParser.new.parse_chapter_pages(test_chapter_contents, [], []) }
     let(:chapter) { { 'name' => "test_chapter" } }
 
     before do
@@ -37,8 +37,8 @@ module Playgroundbook
     end
 
     it "calls the page_writer for each page" do
-      expect(page_writer).to receive(:write_page).with("Page 1", "Page 1.playgroundpage", [], "str = \"Yo, it's page 1.\"\nsharedFunc()", {"name"=>"test_chapter"})
-      expect(page_writer).to receive(:write_page).with("Page 2", "Page 2.playgroundpage", [], "str = \"Page 2 awww yeah.\"\nsharedFunc()", {"name"=>"test_chapter"})
+      expect(page_writer).to receive(:write_page).with("Page 1", "Page 1.playgroundpage", [], "str = \"Yo, it's page 1.\"\nsharedFunc()", [], [], {"name"=>"test_chapter"})
+      expect(page_writer).to receive(:write_page).with("Page 2", "Page 2.playgroundpage", [], "str = \"Page 2 awww yeah.\"\nsharedFunc()", [], [], {"name"=>"test_chapter"})
 
       collator.collate(chapter, parsed_chapter, [])
     end
@@ -47,7 +47,7 @@ module Playgroundbook
       expect { collator.collate(chapter, parsed_chapter, []) }.to_not raise_error
     end
 
-    context "having colated" do
+    context "having collated" do
       before do
         collator.collate(chapter, parsed_chapter, [])
       end

spec/renderer/page_writer_spec.rb

@@ -24,18 +24,18 @@ module Playgroundbook
       end
 
       it "does not explode" do
-        expect { page_writer.write_page(page_name, page_dir_name, ["UIKit"], page_contents) }.to_not raise_error
+        expect { page_writer.write_page(page_name, page_dir_name, ["UIKit"], page_contents, [], []) }.to_not raise_error
       end
     end
 
     it "calls the page processor" do
       expect(page_processor).to receive(:strip_extraneous_newlines)
-      page_writer.write_page(page_name, page_dir_name, ["UIKit"], page_contents)
+      page_writer.write_page(page_name, page_dir_name, ["UIKit"], page_contents, [], [])
     end
 
     context "as a consequence of writing rendering" do
       before do
-        page_writer.write_page(page_name, page_dir_name, ["UIKit"], page_contents)
+        page_writer.write_page(page_name, page_dir_name, ["UIKit"], page_contents, [], [])
       end
 
       it "creates a directory" do