class Selenium::WebDriver::DevTools::NetworkInterceptor

def cancelled?(network_id)
  lock.synchronize { !!cancelled_requests.delete(network_id) }
end

def cancelled_requests
  @cancelled_requests ||= []
end

def continue_request(id)
  devtools.fetch.continue_request(request_id: id)
end

def fetch_response_body(id)
  devtools.fetch.get_response_body(request_id: id).dig('result', 'body')
rescue Error::WebDriverError => e
  raise unless e.message.start_with?(CANNOT_GET_BODY_ON_REDIRECT_ERROR_CODE)
end

def initialize(devtools)
  @devtools = devtools
  @lock = Mutex.new
end

def intercept(&block)
  devtools.network.on(:loading_failed) { |params| track_cancelled_request(params) }
  devtools.fetch.on(:request_paused) { |params| request_paused(params, &block) }
  devtools.network.set_cache_disabled(cache_disabled: true)
  devtools.network.enable
  devtools.fetch.enable(patterns: [{requestStage: 'Request'}, {requestStage: 'Response'}])
end

def intercept_request(id, params, &block)
  original = DevTools::Request.from(id, params)
  mutable = DevTools::Request.from(id, params)
  block.call(mutable) do |&continue|
    pending_response_requests[id] = continue
    if original == mutable
      continue_request(original.id)
    else
      mutate_request(mutable)
    end
  end
end

def intercept_response(id, params)
  return continue_response(id) unless block_given?
  body = fetch_response_body(id)
  original = DevTools::Response.from(id, body, params)
  mutable = DevTools::Response.from(id, body, params)
  yield mutable
  if original == mutable
    continue_response(id)
  else
    mutate_response(mutable)
  end
end

def mutate_request(request)
  devtools.fetch.continue_request(
    request_id: request.id,
    url: request.url,
    method: request.method,
    post_data: (Base64.strict_encode64(request.post_data) if request.post_data),
    headers: request.headers.map do |k, v|
      {name: k, value: v}
    end
  )
end

def mutate_response(response)
  devtools.fetch.fulfill_request(
    request_id: response.id,
    body: (Base64.strict_encode64(response.body) if response.body),
    response_code: response.code,
    response_headers: response.headers.map do |k, v|
      {name: k, value: v}
    end
  )
end

def pending_response_requests
  @pending_response_requests ||= {}
end

def request_paused(data, &block)
  id = data['requestId']
  network_id = data['networkId']
  with_cancellable_request(network_id) do
    if response?(data)
      block = pending_response_requests.delete(id)
      intercept_response(id, data, &block)
    else
      intercept_request(id, data, &block)
    end
  end
end

def response?(params)
  params.key?('responseStatusCode') || params.key?('responseErrorReason')
end

def track_cancelled_request(data)
  return unless data['canceled']
  lock.synchronize { cancelled_requests << data['requestId'] }
end

def with_cancellable_request(network_id)
  yield
rescue Error::WebDriverError => e
  raise if e.message.start_with?(INVALID_INTERCEPTION_ID_ERROR_CODE) && !cancelled?(network_id)
end