# basic idea from
# http://daniel.collectiveidea.com/blog/2007/7/10/a-prettier-truncate-helper
# but we are EVEN awesomer. maybe.

module ActionView::Helpers::TextHelper
  def truncate(text, *args)
    options = args.extract_options!

    # support either old or the Rails 2.2 calling convention:
    unless args.empty?
      options[:length] = args[0] || 30
      options[:omission] = args[1] || "..."
    end
    options.reverse_merge!(:length => 30, :omission => "...")

    # support any of:
    #  * ruby 1.9 sane utf8 support
    #  * rails 2.1 workaround for crappy ruby 1.8 utf8 support
    #  * rails 2.2 workaround for crappy ruby 1.8 utf8 support
    # hooray!
    if text
      chars = if text.respond_to?(:mb_chars)
        text.mb_chars
      elsif RUBY_VERSION < '1.9'
        text.chars
      else
        text
      end

      omission = if options[:omission].respond_to?(:mb_chars)
        options[:omission].mb_chars
      elsif RUBY_VERSION < '1.9'
        options[:omission].chars
      else
        options[:omission]
      end

      l = options[:length] # - omission.length
      if chars.length > options[:length]
        result = (chars[/\A.{#{l}}\w*\;?/m][/.*[\w\;]/m]).to_s
        ((options[:avoid_orphans] && result =~ /\A(.*?)\n+\W*\w*\W*\Z/m) ? $1 : result) + options[:omission]
      else
        text
      end
    end
  end
end