class YARD::Handlers::Ruby::ConstantHandler

def extract_parameters(superclass)
  return [] unless superclass.parameters
  members = superclass.parameters.select {|x| x && x.type == :symbol_literal }
  members.map! {|x| x.source.strip[1..-1] }
  members
end

def process_constant(statement)
  name = statement[0].source
  value = statement[1].source
  obj = P(namespace, name)
  if obj.is_a?(NamespaceObject) && obj.namespace == namespace
    raise YARD::Parser::UndocumentableError, "constant for existing #{obj.type} #{obj}"
  else
    ensure_loaded! obj.parent
    register ConstantObject.new(namespace, name) {|o| o.source = statement; o.value = value.strip }
  end
end

def process_dataclass(statement)
  lhs = statement[0]
  if (lhs.type == :var_field && lhs[0].type == :const) || lhs.type == :const_path_field
    klass = create_class(lhs.source, P(:Data))
    extract_parameters(statement[1]).each do |member|
      next if klass.attributes[:instance][member]
      klass.attributes[:instance][member] = SymbolHash[:read => nil, :write => nil]
      create_reader(klass, member)
    end
    parse_block(statement[1].block[1], :namespace => klass) unless statement[1].block.nil?
  else
    raise YARD::Parser::UndocumentableError, "Data assignment to #{lhs.source}"
  end
end

def process_structclass(statement)
  lhs = statement[0]
  if (lhs.type == :var_field && lhs[0].type == :const) || lhs.type == :const_path_field
    klass = create_class(lhs.source, P(:Struct))
    create_attributes(klass, extract_parameters(statement[1]))
    parse_block(statement[1].block[1], :namespace => klass) unless statement[1].block.nil?
  else
    raise YARD::Parser::UndocumentableError, "Struct assignment to #{lhs.source}"
  end
end