Long word wrap with using Ruby on Rails

long_word_wrap.rb

def long_word_wrap(str, options = {})
  opts = { length: 10000, word_length: 10, shy_length: 4 }.merge(options)
  ret = ''
  offset = 0
  str = truncate(str, length: opts[:length]) if str.length > opts[:length]
  m = str.match(/[^\s\n\r]{#{opts[:word_length]},}/, offset)
  while m
    ret << h(str[offset..m.begin(0)-1]) if offset < m.begin(0)
    s = m[0].scan(/[^\s\n\r]{1,#{opts[:shy_length]}}/)
    ret << s.map{ |x| h(x) }.join('&shy;')
    offset = m.end(0)
    m = str.match(/[^\s\n\r]{#{opts[:word_length],}/, offset)
  end
  ret << h(str[offset..-1])
  ret.html_safe
end