Peak detection with the web audio API?

TL;DR - I want to use Javascript to detect every click in a drummer's click track (an mp3 with only beats in it) and then replace these with .wav samples of a different click sound. The drummer click track is not in constant time, so I can't simply detect the BPM and replace samples from that.

I have a task I'd like to achieve with Javascript and the web audio API, but I'm not sure if it's actually possible using either of these....

Basically I regularly use recorded backing tracks for songs and I replace the default click track (the metronome track that a drummer plays along to) with custom click samples (one .wav sample for the first beat of a bar and another sample for the remaining beats in any given bar). Annoyingly many of these drummer click tracks are not in constant time - so do not have a constant BPM from start to finish.

I want to detect every click in a click track (every peak soundwave) and then replace these with the .wav samples, and download the final file as a MP3. Is this possible?