makeLink.rb

def link(text)
  if (text[/((http:\/\/|ftp:\/\/|https:\/\/|ssh:\/\/|file:\/\/)(([\p{Letter}\p{Number}]+(\-([\p{Letter}\p{Number}]+))?\.)?)([\p{Letter}\p{Number}]+(\-([\p{Letter}\p{Number}]+))?)((\.)(\p{Letter}{2,})){1,2}(\/[\S]*)?)($|\s|\z)/])
    if (text[/(.*)(#{$1})(.*)/])
      return "#{$1}<a href=\"#{$2}\">#{$2}</a>#{$3}"
    end
  elsif (text[/((mailto:)([\p{Letter}\p{Number}\-\.\_]+)(@)(([\p{Letter}\p{Number}]+(\-([\p{Letter}\p{Number}]+))?\.)?)([\p{Letter}\p{Number}]+(\-([\p{Letter}\p{Number}]+))?)((\.)(\p{Letter}{2,})){1,2})($|\s|\z)/])
    if (text[/(.*)(#{$1})(.*)/])
      return "#{$1}<a href=\"#{$2}\">#{$2}</a>#{$3}"
    end
  elsif (text[/((www\.)([\p{Letter}\p{Number}]+(\-([\p{Letter}\p{Number}]+))?)((\.)(\p{Letter}{2,})){1,2}{1,2}(\/[\S]*)?)($|\s|\z)/])
    if (text[/(.*)(#{$1})(.*)/])
      return "#{$1}<a href=\"http://#{$2}\">#{$2}</a>#{$3}"
    end
  elsif (text[/(([\p{Letter}\p{Number}\-\.\_]+)(@)(([\p{Letter}\p{Number}]+(\-([\p{Letter}\p{Number}]+))?\.)?)([\p{Letter}\p{Number}]+(\-([\p{Letter}\p{Number}]+))?)((\.)(\p{Letter}{2,})){1,2})($|\s|\z)/])
    if (text[/(.*)(#{$1})(.*)/])
      return "#{$1}<a href=\"mailto:#{$2}\">#{$2}</a>#{$3}"
    end
  else
    return text
  end
end