Telegram bot for get url's from 9gag / tumblr post

gifscraper_bot.rb

require 'telegram/bot'
require 'uri'
require 'HTTParty'
require 'Nokogiri'

token = 'YOUR_TOKEN_HERE'

class Parser
	def self.parse_9gag page
		page.css('source')
	end

	def self.parse_tumblr page
		page.xpath('//*[@property="og:image"]')
	end

	def self.get_host url
	  url = "http://#{url}" if URI.parse(url).scheme.nil?
	  host = URI.parse(url).host.downcase
	  host.start_with?('www.') ? host[4..-1] : host
	end
end
	
Telegram::Bot::Client.run(token) do |bot|
	bot.listen do |message|
		case message.text
		when '/start'
			bot.api.send_message(chat_id: message.chat.id, text: "Hi, #{message.from.first_name}. Please, send me the url you want to scrap.")
		when URI::regexp
			page = HTTParty.get(message.text)
			html = Nokogiri::HTML(page)
			host = Parser.get_host(message.text)

			case host
			when '9gag.com'
				items = Parser.parse_9gag(html)
			when 'tumblr.com'
				items = Parser.parse_tumblr(html)
			else
				items = []
			end
			
			if items.length == 0 
				bot.api.send_message(chat_id: message.chat.id, text: "Sorry no gifs found :-(")
			else
				items.each { |x| 
					link = x['src'] || x['content']
					bot.api.send_message(chat_id: message.chat.id, text: "Here is your link: #{link}")
				}
			end
		else
			bot.api.send_message(chat_id: message.chat.id, text: "Invalid URL. Try again.")
		end
	end
end