Removing items from an array in both directions-CodePudding

I have an array of times (these are not constant) [1:00, 2:00, 3:00, 4:00, 5:00, 6:00, 7:00]. The goal is to calculate times that can be bookable. If there is an existing booking from 4:00 - 5:00 then 3:00 should be unavailable as it would overlap the existing booking. To calculate this, I have a function that tells us the start and end indexes of the booking, I need to find a way to remove x times from behind the start index.

To make it more clear, I drew a diagram.

Doing this calculation will allow to calculate available times no matter how long the existing booking is. I'm trying to figure out how to create a function that does what I described. Below is the code I have to return the available times based on the start/end index provided however I'm stuck on how to approach the calculation I described above.

 // This filters times that are less than the start index
 const filteredTimes1 = availableHours.filter((item, index) => index < (
      (startTimeIndex || availableHours.length - 0)
 ))
 
 // This filters times that greater than the end index
 const filteredTimes2 = availableHours.filter((item, index) => 
     index > (endTimeIndex || availableHours.length) 
 )
 
 // Then combine the results into an array
 const validAvailableHours = [...filteredTimes1 , ...filteredTimes2]

Any help would be appreciated, thanks.

CodePudding user response：

You're way overcomplicating this.

Just keep a map of the times already booked, in this case 4pm. Later add 3pm since you're adding that too.

Or if you want it simpler just use a Set.

const bookedHours = new Set()

// too add booked times
bookedHours.add(4)

// to get an array with available times
const available = [1,2,3,4,5,23,24]
const availableUpdate = available.filter(n => !bookedHours.has(n))

CodePudding user response：

I mean you could simply use array.slice() to do the trick.

let allHours = [1, 2, 3, 4, 5, 6, 7]

let [startHours, endHours] = [4, 5];  
let duration = 1;

let availableHours = [
  ...allHours.slice(
    0,
    allHours.indexOf(startHours - duration)
  ),
  ...allHours.slice(
    allHours.indexOf(endHours   1)
)]

console.log(availableHours)