A very simple url parser for RichText written in dart

url_parser.dart

static int findEnd(String string, int start) {
  int index = string.indexOf(">", start);
  if (index == -1) {
    return string.length -1;
  } else {
    return index;
  }
}

static List<TextSpan> parseHtml(String html) {
  List<TextSpan> parts = <TextSpan>[];
  int pos = 0;
  if (!html.contains("<a", pos)) {
   parts = [TextSpan(text: html)];
  } else {
    TextStyle linkStyle = const TextStyle(color: Colors.blue);
    do {
      int tagStart = html.indexOf("<a", pos);
      if (tagStart == -1) {
        parts.add(TextSpan(text: html.substring(pos, html.length)));
        pos = html.length;
      } else {
        parts.add(TextSpan(text: html.substring(pos, tagStart)));
        int tagEnd = findEnd(html, tagStart) + 1;
        if (tagEnd > tagStart) {
          String tag = html.substring(tagStart, tagEnd);
          int attrStart = tag.indexOf("href");
          if (attrStart > 0) {
            int valueStart = tag.indexOf("\"") + 1;
            int valueEnd = tag.indexOf("\"", valueStart);
            String target = tag.substring(valueStart, valueEnd);
            int close = html.indexOf("</a>", pos);
            if (close == -1) throw Exception("</a> expected");
            parts.add(TextSpan(
              text: html.substring(tagEnd, close),
              style: linkStyle,
              recognizer: TapGestureRecognizer()
                ..onTap = () {
                  print('Click on ' + target);
                },
            ));
            pos = close + 4;
          }
        }
      }
    } while (pos < html.length);
  }
  return parts;
}