regex.dart

class RegexHelper {
  static String domain = '[a-zA-Z.]+';
  static String protocol = '[a-zA-Z]+:\\/\\/';
  static String www = 'www\\.';

  static String emailName = '[a-zA-Z.+]+';
  static String email = '\\b${emailName}@${domain}\\b';

  static String queryPath = '\\/[-~+=%_a-zA-Z0-9.]+[-~+=%_a-zA-Z0-9]';
  static String searchString = '\\?[-+=&;%@_.a-zA-Z0-9]+[-+=&;%@_a-zA-Z0-9]';
  static String queryHash = '#[-=_a-zA-Z0-9]+';

  static String link = '\\b($protocol|$protocol$www|$www)$domain($queryPath)*(\\/?$searchString)?($queryHash)?';

  static String linkOrEmail = '($email|$link)';
}

main() {
  var input = """
[email protected] <-- link
[email protected] <-- link
[email protected] <-- link
[email protected] <-- link
Hello don't link this.
I am Dave.Noo I am not. <-- don't link this
whatever.com <-- don't link this, only if www and/or http:// precedes it
http://google.ventures <--- Allow new TLDs
www.demo.com <-- link
Have you checked http://foo.co.uk/? <-- don't pick up last ?
Have you checked http://foo.co.uk? <-- don't pick up last ?
Yes, I've checked http://foo.com. <-- don't pick up last .

http://regexr.com/foo.html?q=bar <-- link whole thing.
http://regexr.com/foo.html?q=bar. <-- don't pick up last .
http://regexr.com/foo.html?q=foo.bar. <-- don't pick up last .
http://regexr.com?q=foo.bar. <-- don't pick up last .

www.test.com/?asd=basd

www.test.com/?asd=basd#asd-sdf

ftp://whatever.com <-- link

abc://rad <-- fine to link

http://woven.app/asd?a

http://woven.app/asdasd/asda=sd=

This is a line.
And another line. <-- don't link the two lines.

Screenshot: http://d.pr/i/1kkDd
""";

  print(RegexHelper.linkOrEmail);

  new RegExp(RegexHelper.linkOrEmail).allMatches(input).forEach((Match m) {
    print(m.group(1));
  });
}