module Agents
  class TwitterStreamAgent < Agent
    cannot_receive_events!

    description <<-MD
      The TwitterStreamAgent follows the Twitter stream in real time, watching for certain keywords, or filters, that you provide.

      You must provide an oAuth `consumer_key`, `consumer_secret`, `access_key`, and `access_secret`, as well as an array of `filters`.  Multiple words in a filter
      must all show up in a tweet, but are independent of order.

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

      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.

      `generate` should be either `events` or `counts`.  If set to `counts`, it will output event summaries whenever the Agent is scheduled.
    MD

    event_description <<-MD
      When in `counts` mode, TwitterStreamAgent events look like:

          {
            "filter": "hello world",
            "count": 25,
            "time": 3456785456
          }

      When in `events` mode, TwitterStreamAgent events look like:

          {
            "filter": "selectorgadget",
             ... every Tweet field, including ...
            "text": "something",
            "user": {
              "name": "Mr. Someone",
              "screen_name": "Someone",
              "location": "Vancouver BC Canada",
              "description":  "...",
              "followers_count": 486,
              "friends_count": 1983,
              "created_at": "Mon Aug 29 23:38:14 +0000 2011",
              "time_zone": "Pacific Time (US & Canada)",
              "statuses_count": 3807,
              "lang": "en"
            },
            "retweet_count": 0,
            "entities": ...
            "lang": "en"
          }
    MD

    default_schedule "11pm"

    def validate_options
      unless options[:consumer_key].present? &&
             options[:consumer_secret].present? &&
             options[:access_key].present? &&
             options[:access_secret].present? &&
             options[:filters].present? &&
             options[:expected_update_period_in_days].present? &&
             options[:generate].present?
        errors.add(:base, "expected_update_period_in_days, generate, consumer_key, consumer_secret, access_key, access_secret, and filters are required fields")
      end
    end

    def working?
      (event = event_created_within(options[:expected_update_period_in_days].to_i.days)) && event.payload.present?
    end

    def default_options
      {
          :consumer_key => "---",
          :consumer_secret => "---",
          :access_key => "---",
          :access_secret => "---",
          :filters => %w[keyword1 keyword2],
          :expected_update_period_in_days => "2",
          :generate => "events"
      }
    end

    def process_tweet(filter, status)
      if options[:generate] == "counts"
        # Avoid memory pollution
        me = Agent.find(id)
        me.memory[:filter_counts] ||= {}
        me.memory[:filter_counts][filter.to_sym] ||= 0
        me.memory[:filter_counts][filter.to_sym] += 1
        me.save!
      else
        create_event :payload => status.merge(:filter => filter.to_s)
      end
    end

    def check
      if memory[:filter_counts] && memory[:filter_counts].length > 0
        memory[:filter_counts].each do |filter, count|
          create_event :payload => { :filter => filter.to_s, :count => count, :time => Time.now.to_i }
        end
        memory[:filter_counts] = {}
        save!
      end
    end
  end
end