require 'logger'

require 'nokogiri'
require 'typhoeus'


class MapCrawler
  attr_accessor :base_map_url, :log, :request_pool

  def initialize(base_map_url)
    @base_map_url = base_map_url

    @log = Logger.new(
      File.expand_path('../log/map-crawler.log', File.dirname(__FILE__))
    )
    @log.level = Logger::INFO
    @log.formatter = lambda do |severity, time, prog, message|
      "#{time} - #{severity} - #{message}\n"
    end
  end

  def crawl(city_name_callback = nil)
    city_name_callback ||= lambda { |n| puts n }

    hydra = Typhoeus::Hydra.new(:initial_pool_size => 26)

    ('A'..'Z').each do |letter|
      letter_request = Typhoeus::Request.new(
        @base_map_url.gsub(/\{FIRST_LETTER\}/, letter)
      )
      letter_request.on_complete do |response|
        handle_cities(response, city_name_callback)
      end

      hydra.queue(letter_request)
    end

    hydra.run
  end

  def handle_cities(response, city_name_callback)
    @log.info("Handling cities at url #{response.effective_url}")
    doc = Nokogiri::HTML(response.body)
    doc.css('div.mw-content-ltr ul')[3].css('li a').each do |anchor|
      @log.info("Found city: #{anchor.text}")
      city_name_callback.call(anchor.text.strip)
    end
  end
end