module Vkontakte
  @@secret_key = 'sdgwSbl3nNE4ZxafuPrp'
  
  def self.check params
    unless params[:expire].nil? or params[:mid].nil? or params[:secret].nil? or params[:sid].nil? or params[:sig].nil?
      return true if self.sign(params) == params[:sig]
    end
    false
  end
  
  private
  
  def self.sign params
    Digest::MD5.hexdigest(%w(expire mid secret sid).map{ |_| _+'='+params[_.to_sym] }.join()+@@secret_key)
  end
end