class RSpec::Mocks::Matchers::Receive

def initialize(message, block)
  @message                 = message
  @block                   = block
  @recorded_customizations = []
end

def move_block_to_last_customization(block)
  last = @recorded_customizations.last
  return block unless last
  last.block ||= block
  nil
end

def name
  "receive"
end

def setup_allowance(subject, &block)
  warn_if_any_instance("allow", subject)
  setup_mock_proxy_method_substitute(subject, :add_stub, block)
end

def setup_any_instance_allowance(subject, &block)
  setup_any_instance_method_substitute(subject, :stub, block)
end

def setup_any_instance_expectation(subject, &block)
  setup_any_instance_method_substitute(subject, :should_receive, block)
end

def setup_any_instance_method_substitute(subject, method, block)
  proxy = ::RSpec::Mocks.space.any_instance_proxy_for(subject)
  setup_method_substitute(proxy, method, block)
end

def setup_any_instance_negative_expectation(subject, &block)
  setup_any_instance_method_substitute(subject, :should_not_receive, block)
end

def setup_expectation(subject, &block)
  warn_if_any_instance("expect", subject)
  setup_mock_proxy_method_substitute(subject, :add_message_expectation, block)
end

def setup_method_substitute(host, method, block, *args)
  args << @message.to_sym
  block = move_block_to_last_customization(block)
  expectation = host.__send__(method, *args, &(@block || block))
  @recorded_customizations.each do |customization|
    customization.playback_onto(expectation)
  end
  expectation
end

def setup_mock_proxy_method_substitute(subject, method, block)
  proxy = ::RSpec::Mocks.space.proxy_for(subject)
  setup_method_substitute(proxy, method, block)
end

def setup_negative_expectation(subject, &block)
  # ensure `never` goes first for cases like `never.and_return(5)`,
  # where `and_return` is meant to raise an error
  @recorded_customizations.unshift ExpectationCustomization.new(:never, [], nil)
  warn_if_any_instance("expect", subject)
  setup_expectation(subject, &block)
end

def warn_if_any_instance(expression, subject)
  if AnyInstance::Proxy === subject
    RSpec.warning(
      "`#{expression}(#{subject.klass}.any_instance).to` " <<
      "is probably not what you meant, it does not operate on " <<
      "any instance of `#{subject.klass}`. " <<
      "Use `#{expression}_any_instance_of(#{subject.klass}).to` instead."
    )
  end
end