JS: Check that the substring() does not cut through html tags

What I am doing:

• In NodeJS I am creating an email template by using MustacheJS, using data from an array of JSON objects.


• The text/message that goes in the template can contain text along with basic html tags (such as b p & a).


• Due to limitation of space I need to only show an excerpt of the message. For that I do a word count, and after lets say 20 words (checked by spaces) I truncate the string and append View more anchor tag. This links it to the website's post page, that contains the complete post. Something like:

Hey this is a sample post text <b>message</b>. Lorem ipsum dolor sit amit... <a href="someurl">View more</a>

The problem:

During word count and truncation, it is possible that I truncate the string in between an html tag as I am simply calculating words on basis of space. Something like:

I am sharing a link with you. <a style="color:... <a href="someurl">View more</a>

Now this will break the html.

Possible solution:

• Before truncating string, run a regex on it to find all the html tags in it.


• Use indexOf() (or some other method) to find starting and ending indices of each tag.


• After word count, get the index where I need to truncate it.


• Now see that if the index intersects with any of the tags region.


• If it does intersect, simply move the truncate index to the start or end of the html tag.

Question:

Is there a better way to do this. I don't know what search terms I should be searching on google, to get help with this.

P.S. The code is flexible and I can change the flow if there is a significantly better solution. I am not good with post titles. Please modify it to something that reflects the question.