class MusicBrainzArtist  
  attr_accessor :id, :type, :name, :country, :date_begin, :date_end
  @release_groups
  
  def release_groups
    if @release_groups.nil? and not self.id.nil?
      @release_groups = []
      Nokogiri::XML(open('http://musicbrainz.org/ws/2/release-group/?artist=' + self.id)).css('release-group').each do |rg|
        @release_groups << MusicBrainzReleaseGroup.parse_xml(rg)
      end
    end
    @release_groups
  end
  
  def self.find mbid
    @artist = self.parse_xml(Nokogiri::XML(open('http://musicbrainz.org/ws/2/artist/' + mbid)))
  end
  
  def self.parse_xml xml
    @artist = MusicBrainzArtist.new
    @artist.id = xml.css('artist').attr('id').value
    @artist.type = xml.css('artist').attr('type').value
    @artist.name = xml.css('artist > name').text
    @artist.country = xml.css('artist > country').text || nil
    @artist.date_begin = xml.css('artist > life-span > begin').text || nil
    @artist.date_end = xml.css('artist > life-span > end').text || nil
    @artist
  end
  
end