convert colloquy transcripts into plain text

parse_colloquy.rb

require 'nokogiri'
require 'uri'

INTERESTING_EVENTS = %w(memberJoined memberParted memberNewNickname)

def format_ts(ts)
  ts.sub(/ [+-]\d\d\d\d/, '')
end

Nokogiri::XML(ARGF).css('log').each do |log|
  channel = URI::decode(log.attr('source')[/[^\/]+$/])
  log.css('envelope,event').each do |e|
    case e.name
    when 'envelope'
      sender = e.at_css('sender')&.text
      e.css('message').each do |message|
        ts = format_ts(message.attr('received'))
        puts "#{ts} #{channel} #{sender}: #{message.text.strip}"
      end
    when 'event'
      if INTERESTING_EVENTS.include?(e.attr('name'))
        ts = format_ts(e.attr('occurred'))
        text = e.at_css('message')&.text
        puts "#{ts} #{channel} ** #{text}"
      end
    end
  end
end