class Aws::Stubbing::EmptyStub

def initialize(rules)
  @rules = rules
end

def stub
  if @rules
    stub_ref(@rules)
  else
    EmptyStructure.new
  end
end

def stub_ref(ref, visited = [])
  if visited.include?(ref.shape)
    return nil
  else
    visited = visited + [ref.shape]
  end
  case ref.shape
  when StructureShape then stub_structure(ref, visited)
  when ListShape then []
  when MapShape then {}
  else stub_scalar(ref)
  end
end

def stub_scalar(ref)
  case ref.shape
  when StringShape then ref.shape.name || 'string'
  when IntegerShape then 0
  when FloatShape then 0.0
  when BooleanShape then false
  when TimestampShape then Time.now
  else nil
  end
end

def stub_structure(ref, visited)
  ref.shape.members.inject(ref.shape.struct_class.new) do |struct, (mname, mref)|
    # For eventstream shape, it returns an Enumerator
    unless mref.eventstream
      struct[mname] = stub_ref(mref, visited)
    end
    struct
  end
end