#!/usr/bin/ruby -w

require 'rubygems'
require 'mechanize'

agent = Mechanize.new

page = agent.get("http://weeklybeats.com")
# page now contains the HTML

#get the current week from main page
curWeek = page.search('span[id="listen_week"]').first.children.first.inner_text.to_i

#prepare variables before the loop
previousArtists = Array.new
artistDiff = Array.new

#loop through each week (click on each link on the main page)
(1..curWeek).to_a.each do |i|
  week_num = sprintf("%02d",i)
# this commented line is the original line that worked in 2012, but now gives an error
# results_page = agent.click(page.link_with(:text => "\302\240#{week_num}"))
  results_page = agent.click(page.link_with(:text => /\302\240#{week_num}/))

  artists = Array.new
# add artist name (found in cite tag) to artists list for week_num
  results_page.search('cite').each {|artist| artists << artist.inner_text}

# uncomment to print week# and total artists for that week. broken, maxes at 200
#  puts "#{week_num}  #{artists.length}"

# survivors
  if i > 1
    #use simple set operation to get the survivors
    previousArtists = previousArtists & artists
        puts"#{week_num} #{previousArtists.length}"
  else
    previousArtists = Array.new(artists)
  end
end