Ruby script to search own mt-daapd library and make playlist file of loved tracks on Last.fm

lastfm_loved_playlist_maker.rb

# /usr/local/bin/ruby
require 'nokogiri'
require 'open-uri'
require 'sqlite3'

$user = 'oquno'
$playlist_path = 'favorites.m3u'
$api_key = 'APIKEY HERE'
$sqlite_path = 'songs3.db'

def newtracks
    lasttime = Time.at(File.mtime($playlist_path))
    url = 'http://ws.audioscrobbler.com/2.0/?method=user.getlovedtracks&user='+ $user +'&api_key='+$api_key
    list = []
    xml = Nokogiri::XML(open(url))
    xml.xpath('//track').each do |track|
        if track.xpath('.//date')[0]['uts'].to_i > lasttime.to_i
            title = track.xpath('.//name')[0].content
            artist = track.xpath('.//artist/name')[0].content
            list.push([artist,title])
        else
            break
        end
    end
 
    if list.length != 0
        add(list)
    end
end


def crawl
    base_url = 'http://www.last.fm/user/' + $user + '/library/loved?sortBy=date&sortOrder=desc&page='
    page = 1
    while 1
        list = []
        doc = Nokogiri::HTML(open(base_url + page.to_s))
        if page == 1
            if doc.css('a.lastpage').length != 0
                lastpage = doc.css('a.lastpage')[0].content.to_i
            else
                lastpage = 1
            end 
        end 

        doc.css('td.subjectCell').each do |track|
            artist = track.children[1].content
            title = track.children[3].content
            list.push([artist,title])
        end
        
        add(list)

        if page == lastpage
            break
        end

        page+=1
    end
end

def add(list)
    plist = []
    db = SQLite3::Database.open($sqlite_path)
    list.each{|track|
        q = 'select path from songs where artist="'+track[0]+'" and title="'+track[1]+'"'
        db.query(q) do |row|
            if row
                row.each do |path|
                    plist.push(path)
                end
            end
        end
    }
    db.close()

    if File.exist?($playlist_path)
        f = File.open($playlist_path,'a')
    else
        f = File.open($playlist_path,'w')
    end
    f.puts(plist.join("\n"))
    f.close
end

if ARGV[0] == 'all'
    crawl
elsif ARGV[0] == 'new'
    newtracks
else
    puts 'add "new" or "all"'
end