Timer - countdown understanding

[nbhawnani]

I need some help in understanding how exactly the countdown is supposed to work ? the code of the function is below.

Your code so far

Countdown(){

let newbreaklen=this.state.breaklen;
let newsessionlen=this.state.sessionlen;
let b_newsessionflag=this.state.newsessionflag
let strTimerLabel=this.state.timerlabelstring


if (newbreaklen<=0){
  
  strTimerLabel='New session has begun'
  b_newsessionflag=true
  newbreaklen=5
  newsessionlen=newsessionlen-1
  if (newsessionlen<=0){
    newsessionlen=0
    newbreaklen=this.state.breaklen;
    strTimerLabel='New break has begun'
    b_newsessionflag=false
    
    
  }

}
else{
  newbreaklen=newbreaklen-1;
}

this.setState({breaklen:newbreaklen,sessionlen:newsessionlen,newsessionflag:b_newsessionflag,timerlabelstring:strTimerLabel},()=>{
document.getElementById('time-left').innerHTML=this.state.sessionlen.toString().padStart(2,'0') + ':' + this.state.breaklen.toString().padStart(2,'0');
document.getElementById('timer-label').innerHTML=this.state.timerlabelstring

})

}

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Challenge: Build a 25 + 5 Clock

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