class HTTP::Request::Writer

def add_body_type_headers
  if @body.is_a?(String) && !@headers["Content-Length"]
    @request_header << "Content-Length: #{@body.bytesize}"
  elsif @body.is_a?(Enumerable) && "chunked" != @headers["Transfer-Encoding"]
    fail(RequestError, "invalid transfer encoding")
  end
end

def add_headers
  @headers.each do |field, value|
    @request_header << "#{field}: #{value}"
  end
end

def initialize(socket, body, headers, headerstart) # rubocop:disable ParameterLists
  @body           = body
  @socket         = socket
  @headers        = headers
  @request_header = [headerstart]
  validate_body_type!
end

def join_headers
  # join the headers array with crlfs, stick two on the end because
  # that ends the request header
  @request_header.join(CRLF) + (CRLF) * 2
end

def send_request_body
  if @body.is_a?(String)
    @socket << @body
  elsif @body.is_a?(Enumerable)
    @body.each do |chunk|
      @socket << chunk.bytesize.to_s(16) << CRLF
      @socket << chunk << CRLF
    end
    @socket << "0" << CRLF * 2
  end
end

def send_request_header
  add_headers
  add_body_type_headers
  header = join_headers
  @socket << header
end

def stream
  send_request_header
  send_request_body
end

def validate_body_type!
  return if VALID_BODY_TYPES.any? { |type| @body.is_a? type }
  fail RequestError, "body of wrong type: #{@body.class}"
end