MixpanelHelper

module MixpanelHelper

  def mixpanel_key
   Rails.env.production? ? 'xxx' : 'yyy'
  end

  def mixpanel_track_with_super_properties(event_name, properties = {})
    properties = properties.merge(get_super_properties) unless get_super_properties.nil?
    properties = properties.merge(:distinct_id => mixpanel_distinct_id)
    @mixpanel.track(event_name, properties)
  end

  def mixpanel_set(distinct_id, properties = {})
    @mixpanel.set(distinct_id, properties)
  end

  def mixpanel_track_charge(distinct_id, amount)
    @mixpanel.track_charge(distinct_id, amount.to_f)
  end

  def get_super_properties
    begin
      JSON.parse(cookies[:mp_super_properties]) unless cookies[:mp_super_properties].nil?
    rescue JSON::ParserError => e
      nil
    end
  end

  def get_super_property(key)
    super_properties = get_super_properties
    super_properties[key] unless super_properties.nil?
  end

  def set_super_property(key, value)
    property_hash = { key => value }
    cookies[:mp_super_properties] = {
      :expires => 1.year.from_now,
      :value => cookies[:mp_super_properties].nil? ? property_hash.to_json : get_super_properties.merge(property_hash).to_json
    }
  end

  def remove_super_property(key)
    properties = get_super_properties
    properties.try(:delete, key)
    if properties.blank?
      clear_super_properties
      return
    end
    cookies[:mp_super_properties] = {
      :expires => 1.year.from_now,
      :value => properties.to_json
    }
  end

  def clear_super_properties
    cookies.delete :mp_super_properties
  end

  def set_utm_params_as_super_properties
    set_super_property("utm_campaign", params[:utm_campaign]) if params[:utm_campaign]
    set_super_property("utm_source", params[:utm_source]) if params[:utm_source]
    set_super_property("utm_medium", params[:utm_medium]) if params[:utm_medium]
  end

  def set_utm_params_super_properties_as_user_properties
    mixpanel_set(mixpanel_distinct_id, { :utm_campaign => get_super_property("utm_campaign")}) if get_super_property("utm_campaign")
    mixpanel_set(mixpanel_distinct_id, { :utm_source => get_super_property("utm_source")}) if get_super_property("utm_source")
    mixpanel_set(mixpanel_distinct_id, { :utm_medium => get_super_property("utm_medium")}) if get_super_property("utm_medium")
  end

  def generate_mixpanel_distinct_id
    if cookies[:mixpanel_distinct_id].blank?
      begin
        distinct_id = SecureRandom.urlsafe_base64
      end while User.where(:mixpanel_distinct_id => distinct_id).exists?
      cookies[:mixpanel_distinct_id] = {
        expires: 20.years.from_now,
        value: distinct_id
      }
    end
  end

  def unique_distinct_id?(distinct_id)
    !User.where(:mixpanel_distinct_id => distinct_id).exists?
  end

  def mixpanel_distinct_id
    current_user ? current_user.mixpanel_distinct_id : cookies[:mixpanel_distinct_id]
  end
end