class Seahorse::Client::Http::Response

def body
  @body
end

def body=(io)
  @body = case io
    when nil then StringIO.new('')
    when String then StringIO.new(io)
    else io
  end
end

def body_contents
  if body.is_a?(Array)
    # an array of parsed events
    body
  else
    body.rewind
    contents = body.read
    body.rewind
    contents
  end
end

def emit(event_name, *args)
  @listeners[event_name].each { |listener| listener.call(*args) }
end

def initialize(options = {})
  @status_code = options[:status_code] || 0
  @headers = options[:headers] || Headers.new
  @body = options[:body] || StringIO.new
  @listeners = Hash.new { |h,k| h[k] = [] }
  @complete = false
  @done = nil
  @error = nil
end

def listener(range, callback)
  range = range..range if Integer === range
  if range
    lambda do |*args|
      if range.include?(@status_code)
        callback.call(*args)
      end
    end
  else
    callback
  end
end

def on_data(&callback)
  @listeners[:data] << callback
end

def on_done(status_code_range = nil, &callback)
  listener = listener(status_code_range, callback)
  if @done
    listener.call
  else
    @listeners[:done] << listener
  end
end

def on_error(&callback)
  on_done(0..599) do
    if @error
      yield(@error)
    end
  end
end

def on_headers(status_code_range = nil, &block)
  @listeners[:headers] << listener(status_code_range, block)
end

def on_success(status_code_range = 200..599, &callback)
  on_done(status_code_range) do
    unless @error
      yield
    end
  end
end

def reset
  @status_code = 0
  @headers.clear
  @body.truncate(0)
  @error = nil
end

def signal_data(chunk)
  unless chunk == ''
    @body.write(chunk)
    emit(:data, chunk)
  end
end

def signal_done(options = {})
  if options.keys.sort == [:body, :headers, :status_code]
    signal_headers(options[:status_code], options[:headers])
    signal_data(options[:body])
    signal_done
  elsif options.empty?
    @body.rewind if @body.respond_to?(:rewind)
    @done = true
    emit(:done)
  else
    msg = 'options must be empty or must contain :status_code, :headers, '\
          'and :body'
    raise ArgumentError, msg
  end
end

def signal_error(networking_error)
  @error = networking_error
  signal_done
end

def signal_headers(status_code, headers)
  @status_code = status_code
  @headers = Headers.new(headers)
  emit(:headers, @status_code, @headers)
end