module Vkontakte
  require 'uri'
  require 'net/http'
  require 'erb'
  require 'pp'
  #require 'nokogiri'
  
  @@accounts = YAML.load_file("#{Rails.root.to_s}/config/vk_accounts.yml")
  @@bot = nil
  
  def self.get(artist, track, length)
    self.randomBot()
    html = self.getHtml(artist << ' - ' << track).force_encoding("WINDOWS-1251").encode("UTF-8")
    files = self.parseHtml(html)
    files = self.calcWeight(files, artist, track, length)    
    return {
      'url' => files.first['url'],
      'remixsid' => @@bot['remixsid'],
      'remixchk' => @@bot['remixchk']
    }
  end
  
  
  private
  
  def self.randomBot()
    botname = @@accounts.keys[rand(@@accounts.keys.length - 1)]
    @@bot = @@accounts[botname]
    pp 'Using bot ' << botname
  end
  
  def self.getHtml(q)
    headers = {
      'Cookie'            => 'remixsid='+ @@bot['remixsid'] + ';remixchk='+ @@bot['remixchk'].to_s,
			'Referer'           => 'http://vkontakte.ru/audio?album_id=0',
			'X-Requested-With'  => 'XMLHttpRequest',
			'Origin'            => 'http://vkontakte.ru',
			'Content-Type'      => 'application/x-www-form-urlencoded',
			'User-Agent'        => @@bot['user_agent'],
			'Connection'        => 'close'
    }
    data = {
      'act'			=> 'search',
			'al'			=> 1,
			'gid'			=> 0,
			'id'			=> @@bot['user_id'],
			'offset'  => 0,
			'q'				=> q,
			'sort'		=> 2
    }
    data_str = []
    data.each {|k, v| data_str << k +'='+ ERB::Util.url_encode(v.to_s)}
    
    http = Net::HTTP.new('vkontakte.ru', 80)
    resp, data = http.post('/audio', data_str.join('&'), headers)
    data
  end
  
  def self.parseHtml(html)
    files = []
    html
      .scan(/<table.*?<input.*?value=\"(.*?)\,\d{1,4}\".*?>.*?<div\sclass=\"duration.*?>(.*?)<\/div>.*?<div\sclass=\"title_wrap\".*?>.*?selectPerformer\(event\,\s\'(.*?)\'\).*?<span\sclass=\"title\">(.*?)<\/span><\/div>.*?<\/table>/mi)
        .each do |item|
          t = item[1].split(':')
          files << {
            'url'     => item[0],
            'length'  => (t[0].to_i * 60) + t[1].to_i,
            'artist'  => item[2],
            'track'   => item[3].gsub(/<.*?>/, '')
          }
        end
    files
  end
  
  def self.calcWeight(files, artist, track, length)
    files.each do |file|
      weight = 0
      
      if file['artist'] == artist then weight += 10 else
      if file['artist'].include? artist then weight += 5 else
      if file['track'].include? artist then weight += 4
      end end end
      
      if file['track'] == track then weight += 10 else
      if file['track'].include? track then weight += 5
      end end
      
      if file['length'] == length then weight +=10 else
        delta = (length - file['length']).abs
        if delta < 5 then weight += (5 - delta) end
      end
      
      file['weight'] = weight
    end
    
    files.sort_by{|file| file['weight']}.reverse
  end
end