matches_checker.rb

require 'json'
require 'logger'

class MatchesChecker
  attr_accessor :events_file, :fingerprints_file, :data

  def initialize
    @data = {}
    @events_file = './logs/events.log'
    @fingerprints_file = './logs/fingerprints.log'
    @total_matched = 0
    @current_line = 0
    @lines_logger = Logger.new('./output/lines.log')
    @matches_logger = Logger.new('./output/matches.log')
    @json_output = './output/matches_checker.json'
  end

  def analyze
    load_log_files
    analyze_events
    write_to_file(JSON.pretty_generate(@data))
  end

  private

  def load_log_files
    @events = File.open(@events_file).read
    @fingerprints = File.open(@fingerprints_file).read
  end

  def analyze_events
    @events.lines.each do |line|
      process_line(line)
      @current_line += 1
      @lines_logger.info("Processed #{@current_line} lines of #{@events_file}" \
        " so far.")
    end
  end

  def process_line(line)
    if line.include?('install: SOURCE:')
      check_install(line.split)
    end
  end

  def check_install(splitted_line)
    fingerprint = splitted_line.last
    matched_fingerprint = find_matching_fingerprint(fingerprint)

    unless matched_fingerprint.empty?
      matches = find_matches(fingerprint, matched_fingerprint.first.split(
        'PROPERTIES: ').last)

      save_matches(fingerprint, matches)
    end
  end

  def find_matching_fingerprint(fingerprint)
    @fingerprints.lines.select do |line|
      line =~ /FINGERPRINT: #{fingerprint}/
    end
  end

  def find_matches(fingerprint, properties)
    matched_properties = @fingerprints.lines.select do |line|
      line =~ /#{Regexp.escape(properties)}/
    end
    
    matched_properties.each_with_object([]) do |matched_property, array|
      property_fingerprint = matched_property.split[7]
      array << property_fingerprint unless property_fingerprint == fingerprint
    end
  end

  def save_matches(fingerprint, matches)
    unless matches.empty?
      @data[fingerprint] = matches
      @matches_logger.info("#{fingerprint} matches with #{matches}.")
    end
  end

  def write_to_file(data)
    file = File.open(@json_output, 'w')
    file << data
    file.close
  end
end

MatchesChecker.new.analyze