read from iChat conversation logs using MacRuby

ichat-unarchiver.rb

#!/usr/bin/env macruby

framework 'Foundation'
framework 'AppKit'

class Person
  def initWithCoder(decoder)
  # empty implementation needed for ancient iChat conversations
  end
end

class Presentity
  def initWithCoder(decoder)
    if decoder.allowsKeyedCoding
      @service = decoder.decodeObjectForKey(:ServiceName)
      @sender = decoder.decodeObjectForKey(:ID)
    else
      @service = decoder.decodeObject
      @sender = decoder.decodeObject
    end
    [@service, @sender]
  end
end

class InstantMessage
  def initWithCoder(decoder)
    if decoder.allowsKeyedCoding
      @sender = decoder.decodeObjectForKey(:Sender)
      @when = decoder.decodeObjectForKey(:Time)
      @text = decoder.decodeObjectForKey(:MessageText)
      @flags = decoder.decodeObjectForKey(:Flags)
    else
      @sender = decoder.decodeObject
      @when = decoder.decodeObject
      @text = decoder.decodeObject
      @flags = Pointer.new_with_type('I')
      decoder.decodeValueOfObjCType('I', at: @flags)
    end
    attributes = {NSDocumentTypeDocumentAttribute => NSHTMLTextDocumentType, NSExcludedElementsDocumentAttribute => ['doctype', 'xml', 'html', 'head', 'body']}
    mhtml = @text.dataFromRange(NSMakeRange(0, @text.length), documentAttributes: attributes, error: nil)
    [@sender, @when, NSString.stringWithUTF8String(mhtml)]
  end
end

if __FILE__ == $0
  ARGV.each do |fileName|
    contents = open(fileName, 'rb').read
    o = (contents[0,8] == 'bplist00' ? NSKeyedUnarchiver : NSUnarchiver).unarchiveObjectWithData(contents.to_data)
    puts o.inspect
  end
end