Minecraft username scraper

scraper.rb

module Scraper
  @@lines, @@matches = [], []

  def self.input(filename)
    log = File.open(filename).read
    @@lines.clear
    log.force_encoding("ISO-8859-1")
    log.each_line {|val| @@lines.push(val.encode("UTF-8"))}
  end

  def self.filter_chat
    # must be a chat message, and not a warning
    @@lines.keep_if {|val| val.match(/\[CHAT\]/)}
  end

  def self.filter_possible_usernames
    # must include an alphanumeric or underscore string 3 to 16 characters in length
    # that is not preceded or followed by alphanumeric or underscore characters
    @@lines.keep_if {|val| val.match(/(^|[^\w_])([\w_]{3,16})($|[^\w_])/)}
  end

  def self.strip_thread_info
    @@lines = @@lines.map {|val| val.gsub(/.*\[CHAT\] /, "").strip}
  end

  def self.strip_formatting
    @@lines = @@lines.map {|val| val.gsub(/§\w/, "")}
  end

  def self.output filename
    a = File.open(filename, "w")
    a << @@matches.join("\n")
    a.close
  end

  PATTERNS =
    [
      # Hypixel
      /^(?:\[(?:VIP|MVP|HELPER|MOD|YT|MOJANG|ADMIN|OWNER|Mystery Box|\?)\+?\]\s)?([\w]{3,16})(?: joined| left|:| found).*/
    ]

  UNLIKELY_NAMES = 
    [
      /^you$/i,
      /^winners?$/i,
      /^kits?$/i,
      /^owners?$/i,
      /^members?$/i,
      /^flags?$/i,
      /^usernames?$/i,
      /^regions?$/i,
      /^scores?$/i,
      /^teams?$/i,
      /^bounds?$/i,
      /^co-?ord(inate)?s$/i,
      /^sides?$/i,
      /^objectives?$/i,
      /^points?$/i,
      /^checkpoints?$/i,
    ]

  def self.find_patterns keep_unlikelies = false
    @@matches = []
    PATTERNS.each do |pattern|
      @@lines.each do |val|
        found = val.match(pattern)
        @@matches.push (found)[1] if found
      end
    end
    @@matches.uniq!
    @@matches.sort!
    if !keep_unlikelies
      UNLIKELY_NAMES.each do |pattern|
        @@matches.delete_if {|val| val.match(pattern)} 
      end
    end
  end

end

keep_unlikelies = ARGV[-1] =~ /all/i
if keep_unlikelies
  ARGV.pop
end
file_in, file_out = ARGV
file_in ||= "./latest.log"
file_out ||= "./out.txt"

Scraper.input file_in
Scraper.filter_chat
Scraper.strip_thread_info
Scraper.filter_possible_usernames
Scraper.strip_formatting
Scraper.find_patterns(keep_unlikelies)
Scraper.output file_out