require 'date'
require 'cgi'

module Agents
  class WeatherAgent < Agent
    cannot_receive_events!

    gem_dependency_check { defined?(Wunderground) && defined?(ForecastIO) }

    description <<-MD
      The Weather Agent creates an event for the day's weather at a given `location`.

      #{'## Include `forecast_io` and `wunderground` in your Gemfile to use this Agent!' if dependencies_missing?}

      You also must select `which_day` you would like to get the weather for where the number 0 is for today and 1 is for tomorrow and so on. Weather is only returned for 1 week at a time.

      The weather can be provided by either Wunderground or Dark Sky. To choose which `service` to use, enter either `darksky` or `wunderground`.

      The `location` should be:

      * For Wunderground: A US zipcode, or any location that Wunderground supports. To find one, search [wunderground.com](http://wunderground.com) and copy the location part of the URL.  For example, a result for San Francisco gives `http://www.wunderground.com/US/CA/San_Francisco.html` and London, England gives `http://www.wunderground.com/q/zmw:00000.1.03772`.  The locations in each are `US/CA/San_Francisco` and `zmw:00000.1.03772`, respectively.
      * For Dark Sky: `location` must be a comma-separated string of co-ordinates (longitude, latitude). For example, San Francisco would be `37.7771,-122.4196`.

      You must setup an [API key for Wunderground](http://www.wunderground.com/weather/api/) in order to use this Agent with Wunderground.

      You must setup an [API key for Dark Sky](https://darksky.net/dev/) in order to use this Agent with Dark Sky.

      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.

      If you want to see the returned texts in your language, then set the `language` parameter in ISO 639-1 format.
    MD

    event_description <<-MD
      Events look like this:

          {
            "location": "12345",
            "date": {
              "epoch": "1357959600",
              "pretty": "10:00 PM EST on January 11, 2013"
            },
            "high": {
              "fahrenheit": "64",
              "celsius": "18"
            },
            "low": {
              "fahrenheit": "52",
              "celsius": "11"
            },
            "conditions": "Rain Showers",
            "icon": "rain",
            "icon_url": "http://icons-ak.wxug.com/i/c/k/rain.gif",
            "skyicon": "mostlycloudy",
            ...
          }
    MD

    default_schedule "8pm"

    def working?
      event_created_within?((interpolated['expected_update_period_in_days'].presence || 2).to_i) && !recent_error_logs? && key_setup?
    end

    def key_setup?
      interpolated['api_key'].present? && interpolated['api_key'] != "your-key" && interpolated['api_key'] != "put-your-key-here"
    end

    def default_options
      {
        'service' => 'wunderground',
        'api_key' => 'your-key',
        'location' => '94103',
        'which_day' => '1',
        'language' => 'EN',
        'expected_update_period_in_days' => '2'
      }
    end

    def check
      if key_setup?
        create_event :payload => model(weather_provider, which_day).merge('location' => location)
      end
    end

    private

    def weather_provider
      interpolated["service"].presence || "wunderground"
    end

    def which_day
      (interpolated["which_day"].presence || 1).to_i
    end

    def location
      interpolated["location"].presence || interpolated["zipcode"]
    end

    def language
      interpolated['language'].presence || 'EN'
    end

    def validate_options
      errors.add(:base, "service must be set to 'darksky' or 'wunderground'") unless %w[darksky forecastio wunderground].include?(weather_provider)
      errors.add(:base, "location is required") unless location.present?
      errors.add(:base, "api_key is required") unless interpolated['api_key'].present?
      errors.add(:base, "which_day selection is required") unless which_day.present?
    end

    def wunderground
      if key_setup?
        forecast = Wunderground.new(interpolated['api_key'], language: language.upcase).forecast_for(location)
        merged = {}
        forecast['forecast']['simpleforecast']['forecastday'].each { |daily| merged[daily['period']] = daily }
        forecast['forecast']['txt_forecast']['forecastday'].each { |daily| (merged[daily['period']] || {}).merge!(daily) }
        merged
      end
    end

    def dark_sky
      if key_setup?
        ForecastIO.api_key = interpolated['api_key']
        lat, lng = location.split(',')
        ForecastIO.forecast(lat, lng, params: {lang: language.downcase})['daily']['data']
      end
    end

    def model(weather_provider,which_day)
      if weather_provider == "wunderground"
        wunderground[which_day]
      elsif weather_provider == "darksky" || weather_provider == "forecastio"
        dark_sky.each do |value|
          timestamp = Time.at(value.time)
          if (timestamp.to_date - Time.now.to_date).to_i == which_day
            day = {
              'date' => {
                'epoch' => value.time.to_s,
                'pretty' => timestamp.strftime("%l:%M %p %Z on %B %d, %Y"),
                'day' => timestamp.day,
                'month' => timestamp.month,
                'year' => timestamp.year,
                'yday' => timestamp.yday,
                'hour' => timestamp.hour,
                'min' => timestamp.strftime("%M"),
                'sec' => timestamp.sec,
                'isdst' => timestamp.isdst ? 1 : 0 ,
                'monthname' => timestamp.strftime("%B"),
                'monthname_short' => timestamp.strftime("%b"),
                'weekday_short' => timestamp.strftime("%a"),
                'weekday' => timestamp.strftime("%A"),
                'ampm' => timestamp.strftime("%p"),
                'tz_short' => timestamp.zone
              },
              'period' => which_day.to_i,
              'high' => {
                'fahrenheit' => value.temperatureMax.round().to_s,
                'epoch' => value.temperatureMaxTime.to_s,
                'fahrenheit_apparent' => value.apparentTemperatureMax.round().to_s,
                'epoch_apparent' => value.apparentTemperatureMaxTime.to_s,
                'celsius' => ((5*(Float(value.temperatureMax) - 32))/9).round().to_s
              },
              'low' => {
                'fahrenheit' => value.temperatureMin.round().to_s,
                'epoch' => value.temperatureMinTime.to_s,
                'fahrenheit_apparent' => value.apparentTemperatureMin.round().to_s,
                'epoch_apparent' => value.apparentTemperatureMinTime.to_s,
                'celsius' => ((5*(Float(value.temperatureMin) - 32))/9).round().to_s
              },
              'conditions' => value.summary,
              'icon' => value.icon,
              'avehumidity' => (value.humidity * 100).to_i,
              'sunriseTime' => value.sunriseTime.to_s,
              'sunsetTime' => value.sunsetTime.to_s,
              'moonPhase' => value.moonPhase.to_s,
              'precip' => {
                'intensity' => value.precipIntensity.to_s,
                'intensity_max' => value.precipIntensityMax.to_s,
                'intensity_max_epoch' => value.precipIntensityMaxTime.to_s,
                'probability' => value.precipProbability.to_s,
                'type' => value.precipType
              },
              'dewPoint' => value.dewPoint.to_s,
              'avewind' => {
                'mph' => value.windSpeed.round().to_s,
                'kph' =>  (Float(value.windSpeed) * 1.609344).round().to_s,
                'degrees' => value.windBearing.to_s
              },
              'visibility' => value.visibility.to_s,
              'cloudCover' => value.cloudCover.to_s,
              'pressure' => value.pressure.to_s,
              'ozone' => value.ozone.to_s
            }
            return day
          end
        end
      end
    end
  end
end