require "twitter"

module Agents
  class TwitterPublishAgent < Agent
    include TwitterConcern
    cannot_be_scheduled!

    description <<-MD
      The TwitterPublishAgent publishes tweets from the events it receives.

      Twitter credentials must be supplied as either [credentials](/user_credentials) called
      `twitter_consumer_key`, `twitter_consumer_secret`, `twitter_oauth_token`, and `twitter_oauth_token_secret`,
      or as options to this Agent called `consumer_key`, `consumer_secret`, `oauth_token`, and `oauth_token_secret`.

      To get oAuth credentials for Twitter, [follow these instructions](https://github.com/cantino/huginn/wiki/Getting-a-twitter-oauth-token).

      You must also specify a `message_path` parameter: a [JSONPaths](http://goessner.net/articles/JsonPath/) to the value to tweet.

      Set `expected_update_period_in_days` to the maximum amount of time that you'd expect to pass between Events being created by this Agent.
    MD

    def validate_options
      errors.add(:base, "expected_update_period_in_days is required") unless options['expected_update_period_in_days'].present?
    end

    def working?
      event_created_within?(options['expected_update_period_in_days']) && most_recent_event.payload['success'] == true && !recent_error_logs?
    end

    def default_options
      {
        'expected_update_period_in_days' => "10",
        'message_path' => "text"
      }
    end

    def receive(incoming_events)
      # if there are too many, dump a bunch to avoid getting rate limited
      if incoming_events.count > 20
        incoming_events = incoming_events.first(20)
      end
      incoming_events.each do |event|
        tweet_text = Utils.value_at(event.payload, options['message_path'])
        begin
          publish_tweet tweet_text
          create_event :payload => {
            'success' => true,
            'published_tweet' => tweet_text,
            'agent_id' => event.agent_id,
            'event_id' => event.id
          }
        rescue Twitter::Error => e
          create_event :payload => {
            'success' => false,
            'error' => e.message,
            'failed_tweet' => tweet_text,
            'agent_id' => event.agent_id,
            'event_id' => event.id
          }
        end
      end
    end

    def publish_tweet(text)
      Twitter.update(text)
    end
  end
end