gistfile1.rb

# Returns hierarchical data structure rooted at this node.  When converting to
# json make sure to remove :parent to avoid circular reference:
# message.full_hierarchy.to_json(:only => [:id, :subject, :children, ...])
def full_hierarchy
  the_full_set = full_set
  ancestry = [build_node(the_full_set.shift)]
  while !the_full_set.empty?
    next_node = build_node(the_full_set.shift)
    while next_node[:level] <= ancestry.last[:level]
      ancestry.pop
    end
    ancestry.last[:children] << next_node
    ancestry.last[:leaf] = false
    next_node[:parent] = ancestry.last
    ancestry << next_node
  end
  ancestry[0]
end

private

# active record Message to node for hierarchy
def build_node(message)
  ret = {}
  ret[:id] = message.id
  ret[:subject] = message.subject
  ret[:message] = message.message
  ret[:level] = message.level
  ret[:account_id] = message.account_id
  ret[:author] = message.account.login
  ret[:children] = []
  ret[:parent] = nil
  ret[:leaf] = true
  ret
end