Calculates how many chapters of a book to read each day

index.js

function calculateReading(chapters, days) {

    return mike(chapters, days, 1);

}

function mike(chapters, days, dayNumber, endedOn) {
    
    var result = (chapters % days);
    var c=[];
  
    var chaptersDay=(chapters/days);

    startChapter=dayNumber;

    if (days===1) {
        c.push(onlyOne(chapters, dayNumber, endedOn));
        return c;
    }

    if (result===0) {
        c.push([...perfectlyEven(days, chaptersDay, dayNumber)]);
       
    } else {  
      
        let firstDay=Math.ceil(chaptersDay);
        var w={};
                
        w.day="dd-day " + dayNumber;

        var bgn2;
        var end2;

        if (endedOn) {
            bgn2 = (1+endedOn);
            end2 = (endedOn+firstDay);
        } else {
            bgn2=1;
            end2 = firstDay;
        }    
                        
        w.chapters="chaps. " + bgn2 + " thru " + end2;

        c.push(w);    

        var f=mike((chapters-firstDay),(days-1),(dayNumber+1), end2)
        c.push([...f]);
    }   
    
      return c;   
}

function perfectlyEven(chapters, days, dayNumber) {

    let c=[];

    for (var i = 0; i < days; i++) { 
        
        var y={};
        
        y.day="day " + (i+dayNumber)
        
        var bgn=1+(chapters*i);
        var end=chapters+(chapters*i);
                    
        y.chapters="chaps. " + bgn + "-" + end;
        c.push(y)
        
    }

    return c;

}

function onlyOne(chapters, dayNumber, endedOn) {
    
    var y={};
    
    y.day="only-one-day " + dayNumber;
    var endChapter=(chapters+endedOn);
                
    y.chapters="chaps. " + startChapter + " thru " + endChapter;

    return y;

}

//console.log(calculateReading(50,10));
//console.log(calculateReading(7,1));
//console.log(calculateReading(22,1));

console.log(calculateReading(7,2));