Checkout of Instiki Trunk 1/21/2007.

lib/page_renderer.rb

@@ -0,0 +1,134 @@
+require 'diff'
+# Temporary class containing all rendering stuff from a Revision 
+# I want to shift all rendering loguc to the controller eventually
+
+class PageRenderer
+
+  include HTMLDiff
+
+  def self.setup_url_generator(url_generator)
+    @@url_generator = url_generator
+  end
+
+  def self.teardown_url_generator
+    @@url_generator = nil
+  end
+
+  attr_reader :revision
+
+  def initialize(revision = nil)
+    self.revision = revision
+  end
+
+  def revision=(r)
+    @revision = r
+    @display_content = @display_published = @wiki_words_cache = @wiki_includes_cache = 
+        @wiki_references_cache = nil
+  end
+
+  def display_content(update_references = false)
+    @display_content ||= render(:update_references => update_references)
+  end
+
+  def display_content_for_export
+    render :mode => :export
+  end
+
+  def display_published
+    @display_published ||= render(:mode => :publish)
+  end
+
+  def display_diff
+    previous_revision = @revision.page.previous_revision(@revision)
+    if previous_revision
+      rendered_previous_revision = WikiContent.new(previous_revision, @@url_generator).render!
+      diff(rendered_previous_revision, display_content) 
+    else
+      display_content
+    end
+  end
+
+  # Returns an array of all the WikiIncludes present in the content of this revision.
+  def wiki_includes
+    unless @wiki_includes_cache 
+      chunks = display_content.find_chunks(Include)
+      @wiki_includes_cache = chunks.map { |c| ( c.escaped? ? nil : c.page_name ) }.compact.uniq
+    end
+    @wiki_includes_cache
+  end
+
+  # Returns an array of all the WikiReferences present in the content of this revision.
+  def wiki_references
+    unless @wiki_references_cache 
+      chunks = display_content.find_chunks(WikiChunk::WikiReference)
+      @wiki_references_cache = chunks.map { |c| ( c.escaped? ? nil : c.page_name ) }.compact.uniq
+    end
+    @wiki_references_cache
+  end
+
+  # Returns an array of all the WikiWords present in the content of this revision.
+  def wiki_words
+    @wiki_words_cache ||= find_wiki_words(display_content) 
+  end
+
+  def find_wiki_words(rendering_result)
+    wiki_links = rendering_result.find_chunks(WikiChunk::WikiLink)
+    # Exclude backslash-escaped wiki words, such as \WikiWord, as well as links to files 
+    # and pictures, such as [[foo.txt:file]] or [[foo.jpg:pic]]
+    wiki_links.delete_if { |link| link.escaped? or [:pic, :file].include?(link.link_type) }
+    # convert to the list of unique page names
+    wiki_links.map { |link| ( link.page_name ) }.uniq
+  end
+
+  # Returns an array of all the WikiWords present in the content of this revision.
+  # that already exists as a page in the web.
+  def existing_pages
+    wiki_words.select { |wiki_word| @revision.page.web.page(wiki_word) }
+  end
+
+  # Returns an array of all the WikiWords present in the content of this revision
+  # that *doesn't* already exists as a page in the web.
+  def unexisting_pages
+    wiki_words - existing_pages
+  end  
+
+  private
+  
+  def render(options = {})
+    rendering_result = WikiContent.new(@revision, @@url_generator, options).render!
+    update_references(rendering_result) if options[:update_references]
+    rendering_result
+  end
+  
+  def update_references(rendering_result)
+    WikiReference.delete_all ['page_id = ?', @revision.page_id]
+
+    references = @revision.page.wiki_references
+
+    wiki_words = find_wiki_words(rendering_result)
+    # TODO it may be desirable to save links to files and pictures as WikiReference objects
+    # present version doesn't do it
+    
+    wiki_words.each do |referenced_name|
+      # Links to self are always considered linked
+      if referenced_name == @revision.page.name
+        link_type = WikiReference::LINKED_PAGE
+      else
+        link_type = WikiReference.link_type(@revision.page.web, referenced_name)
+      end
+      references.create :referenced_name => referenced_name, :link_type => link_type
+    end
+    
+    include_chunks = rendering_result.find_chunks(Include)
+    includes = include_chunks.map { |c| ( c.escaped? ? nil : c.page_name ) }.compact.uniq
+    includes.each do |included_page_name|
+      references.create :referenced_name => included_page_name, 
+          :link_type => WikiReference::INCLUDED_PAGE
+    end
+    
+    categories = rendering_result.find_chunks(Category).map { |cat| cat.list }.flatten
+    categories.each do |category|
+      references.create :referenced_name => category, :link_type => WikiReference::CATEGORY
+    end
+  end
+end