Javascript how to merge or combine array of days with same opening hours

I have an array of days and the opening hours:

let arrData = [
{
  "dayOfTheWeek":"Monday",
  "isOpen":true,
  "hoursOfBusiness":[
     {
        "opensAt":"10:00:00",
        "closesAt":"15:00:00"
     }
  ]
},
{
  "dayOfTheWeek":"Tuesday",
  "isOpen":true,
  "hoursOfBusiness":[
     {
        "opensAt":"10:00:00",
        "closesAt":"15:00:00"
     }
  ]
},
{
  "dayOfTheWeek":"Wednesday",
  "isOpen":true,
  "hoursOfBusiness":[
     {
        "opensAt":"10:00:00",
        "closesAt":"15:00:00",
     }
  ]
},
{
  "dayOfTheWeek":"Thursday",
  "isOpen":true,
  "hoursOfBusiness":[
     {
        "opensAt":"09:00:00",
        "closesAt":"16:00:00",
     }
  ]
},
{
  "dayOfTheWeek":"Friday",
  "isOpen":true,
  "hoursOfBusiness":[
     {
        "opensAt":"10:00:00",
        "closesAt":"14:00:00",
     }
  ]
},
{
  "dayOfTheWeek":"Saturday",
  "isOpen":false,
  "hoursOfBusiness":[]
},
{
  "dayOfTheWeek":"Sunday",
  "isOpen":false,
  "hoursOfBusiness":[]
}
]

And I want to combine the days where the opening hours are the same. So, basically my goal is to display the opening hours like this:

Monday-Wednesday: 10-15
Thursday: 9-16
Friday: 10-14

So, I tried to to this:

function openingHours(data){
   let merged = [];
   let idx = -1;
   for (let i = 0; i < data.length; i++) {
     let day = data[i];
     if (
       idx == -1 ||
       merged[idx].hoursOfBusiness.opensAt != day.hoursOfBusiness.opensAt
     ) {
      merged.push({
        days: day.dayOfTheWeek,
        opensAt: day.hoursOfBusiness.opensAt,
        closesAt: day.hoursOfBusiness.closesAt,
      });
     idx++;
    } else {
      merged[idx].days.push(day.dayOfTheWeek);
    }
  }
 return merged;
}

but this doesn’t really work. I have created a JSFIDDLE so please check it out.

Can someone help me out?

UPDATE

All answers were pretty useful but actually I need a different output after all, since the opening/closing hours can vary, I need something like:

data: [
   {
     days: "Monday-Wednesday",
     opensAt: "10:00",
     closesAt: "15:00
   },
   {
     days: "Thursday",
     opensAt: "09:00",
     closesAt: "16:00
   },
   {
     days: "Friday",
     opensAt: "10:00",
     closesAt: "14:00
   },
]

I hope someone could help me out?

Answer

There are some issues with the data/code

1. the hoursOfBusiness in the data is an array
2. the hoursOfBusiness in merged item is not available – u have directly added the opensAt property to it
3. Not all the items have data into it – hoursOfBusiness for saturday and sunday is empty array

Below is the updated code considering the data as you have provided, and also considering that in your merged object you don’t need array

function openingHours(data){
  let merged = [];
  let idx = -1;
  for (let i = 0; i < data.length; i++) {
    let day = data[i];
    if(day.hoursOfBusiness.length == 0){
    continue
    }
    if (
      idx == -1 ||
      merged[idx].opensAt != day.hoursOfBusiness[0].opensAt
    ) {
      merged.push({
        days: [day.dayOfTheWeek],
        opensAt: day.hoursOfBusiness[0].opensAt,
        closesAt: day.hoursOfBusiness[0].closesAt,
      });
      idx++;
    } else {
      merged[idx].days.push(day.dayOfTheWeek);
    }
  }
  return merged;
}

console.log(openingHours(arrData))