module Agents
  class WebhookAgent < Agent
    cannot_be_scheduled!
    cannot_receive_events!

    description do <<-MD
      The Webhook Agent will create events by receiving webhooks from any source. In order to create events with this agent, make a POST request to:

      ```
         https://#{ENV['DOMAIN']}/users/#{user.id}/web_requests/#{id || ':id'}/#{options['secret'] || ':secret'}
      ```

      #{'The placeholder symbols above will be replaced by their values once the agent is saved.' unless id}

      Options:

        * `secret` - A token that the host will provide for authentication.
        * `expected_receive_period_in_days` - How often you expect to receive
          events this way. Used to determine if the agent is working.
        * `payload_path` - JSONPath of the attribute in the POST body to be
          used as the Event payload.  If `payload_path` points to an array,
          Events will be created for each element.
      MD
    end

    event_description do
      <<-MD
        The event payload is based on the value of the `payload_path` option,
        which is set to `#{interpolated['payload_path']}`.
      MD
    end

    def default_options
      { "secret" => "supersecretstring",
        "expected_receive_period_in_days" => 1,
        "payload_path" => "some_key"
      }
    end

    def receive_web_request(params, method, format)
      secret = params.delete('secret')
      return ["Please use POST requests only", 401] unless method == "post"
      return ["Not Authorized", 401] unless secret == interpolated['secret']

      [payload_for(params)].flatten.each do |payload|
        create_event(payload: payload)
      end

      ['Event Created', 201]
    end

    def working?
      event_created_within?(interpolated['expected_receive_period_in_days']) && !recent_error_logs?
    end

    def validate_options
      unless options['secret'].present?
        errors.add(:base, "Must specify a secret for 'Authenticating' requests")
      end
    end

    def payload_for(params)
      Utils.value_at(params, interpolated['payload_path']) || {}
    end
  end
end