Checkout of Instiki Trunk 1/21/2007.

app/models/page.rb

@@ -0,0 +1,121 @@
+class Page < ActiveRecord::Base
+  belongs_to :web
+  has_many :revisions, :order => 'id'
+  has_many :wiki_references, :order => 'referenced_name'
+  has_one :current_revision, :class_name => 'Revision', :order => 'id DESC'
+
+  def revise(content, time, author, renderer)
+    revisions_size = new_record? ? 0 : revisions.size
+    if (revisions_size > 0) and content == current_revision.content
+      raise Instiki::ValidationError.new(
+          "You have tried to save page '#{name}' without changing its content")
+    end
+    
+    author = Author.new(author.to_s) unless author.is_a?(Author)
+
+    # Try to render content to make sure that markup engine can take it,
+    renderer.revision = Revision.new(
+       :page => self, :content => content, :author => author, :revised_at => time)
+    renderer.display_content(update_references = true)
+
+    # A user may change a page, look at it and make some more changes - several times.
+    # Not to record every such iteration as a new revision, if the previous revision was done 
+    # by the same author, not more than 30 minutes ago, then update the last revision instead of
+    # creating a new one
+    if (revisions_size > 0) && continous_revision?(time, author)
+      current_revision.update_attributes(:content => content, :revised_at => time)
+    else
+      revisions.create(:content => content, :author => author, :revised_at => time)
+    end
+    save
+    self
+  end
+
+  def rollback(revision_number, time, author_ip, renderer)
+    roll_back_revision = self.revisions[revision_number]
+    if roll_back_revision.nil?
+      raise Instiki::ValidationError.new("Revision #{revision_number} not found")
+    end
+    author = Author.new(roll_back_revision.author.name, author_ip)
+    revise(roll_back_revision.content, time, author, renderer)
+  end
+
+  def revisions?
+    revisions.size > 1
+  end
+
+  def previous_revision(revision)
+    revision_index = revisions.each_with_index do |rev, index| 
+      if rev.id == revision.id 
+        break index 
+      else
+        nil
+      end
+    end
+    if revision_index.nil? or revision_index == 0
+      nil
+    else
+      revisions[revision_index - 1]
+    end
+  end
+
+  def references
+    web.select.pages_that_reference(name)
+  end
+
+  def wiki_words
+    wiki_references.select { |ref| ref.wiki_word? }.map { |ref| ref.referenced_name }
+  end
+
+  def linked_from
+    web.select.pages_that_link_to(name)
+  end
+
+  def included_from
+    web.select.pages_that_include(name)
+  end
+
+  # Returns the original wiki-word name as separate words, so "MyPage" becomes "My Page".
+  def plain_name
+    web.brackets_only? ? name : WikiWords.separate(name)
+  end
+
+  LOCKING_PERIOD = 30.minutes
+
+  def lock(time, locked_by)
+    update_attributes(:locked_at => time, :locked_by => locked_by)
+  end
+  
+  def lock_duration(time)
+    ((time - locked_at) / 60).to_i unless locked_at.nil?
+  end
+  
+  def unlock
+    update_attribute(:locked_at, nil)
+  end
+  
+  def locked?(comparison_time)
+    locked_at + LOCKING_PERIOD > comparison_time unless locked_at.nil?
+  end
+
+  def to_param
+    name
+  end
+
+  private
+
+    def continous_revision?(time, author)
+      (current_revision.author == author) && (revised_at + 30.minutes > time)
+    end
+
+    # Forward method calls to the current revision, so the page responds to all revision calls
+    def method_missing(method_id, *args, &block)
+      method_name = method_id.to_s
+      # Perform a hand-off to AR::Base#method_missing
+      if @attributes.include?(method_name) or md = /(=|\?|_before_type_cast)$/.match(method_name)
+        super(method_id, *args, &block)
+      else
+        current_revision.send(method_id)
+      end
+    end
+end