module CartoJson
  class Circle < Point
    type :circle

    attr_accessor :radius

    def radius=(r)
      raise InvalidRadiusError, 'radius cannot be negative' if r < 0
      raise InvalidRadiusError, 'radius cannot be blank'    if r.nil?
      raise InvalidRadiusError, 'radius must be a number'   unless (r.is_a?(Integer) || r.is_a?(Float))
      raise InvalidRadiusError, 'radius cannot be zero'     if r == 0
      @radius = r
    end

    def to_wkt
      raise NotImplementedError, 'WKT does not support circles directly, conversion to polygon is required'
    end

    def to_point
      Point.new LAT => send(LAT), LNG => send(LNG)
    end

    def to_hash
      {:type    => self.class.type,
       :center  => {
         LAT   => send(LAT),
         LNG   => send(LNG)
        },
        :radius => radius
      }
    end
  end
end