parse JSON array in swift , sort it and find overlapping dates

Question

How do I parse this? The array is unnamed, the objects are unnamed? I also need to sort it and find overlaps(identify conflicts) between events IF you guys have any advice there too it will be a huge help for me.

[{"title": "Evening Picnic", "start": "November 10, 2018 6:00 PM", "end": "November 10, 2018 7:00 PM"}, {"title": "Nap Break", "start": "November 8, 2018 12:56 PM", "end": "November 8, 2018 1:30 PM"}, {"title": "Football Game", "start": "November 3, 2018 6:14 PM", "end": "November 3, 2018 9:44 PM"}, {"title": "Evening Cookout with Friends", "start": "November 6, 2018 5:00 PM", "end": "November 6, 2018 10:00 PM"}, {"title": "Roller Derby", "start": "November 7, 2018 12:00 PM", "end": "November 7, 2018 2:30 PM"}, {"title": "Basketball Game", "start": "November 8, 2018 7:30 PM", "end": "November 8, 2018 10:30 PM"}, {"title": "Local Pub with Friends", "start": "November 1, 2018 7:33 PM", "end": "November 1, 2018 11:00 PM"}, {"title": "Dentist Appointment", "start": "November 10, 2018 1:45 PM", "end": "November 10, 2018 2:30 PM"}, {"title": "Volleyball With Friends", "start": "November 6, 2018 12:00 PM", "end": "November 6, 2018 1:26 PM"}, {"title": "Free Donuts", "start": "November 9, 2018 3:00 PM", "end": "November 9, 2018 4:00 PM"}, {"title": "TV Show Marathon", "start": "November 9, 2018 4:30 PM", "end": "November 9, 2018 9:00 PM"}, {"title": "Boba Tea Grand Opening", "start": "November 6, 2018 1:27 PM", "end": "November 6, 2018 2:00 PM"}, {"title": "Lunch with Friends", "start": "November 8, 2018 11:30 AM", "end": "November 8, 2018 12:59 PM"}, {"title": "SF Coffee Festival","start": "November 6, 2018 6:00 PM","end": "November 6, 2018 9:00 PM"}, {"title": "Beer with Friends", "start": "November 9, 2018 8:00 PM", "end": "November 9, 2018 9:30 PM"}, {"title": "Yoga", "start": "November 1, 2018 6:00 PM", "end": "November 1, 2018 7:33 PM"}, {"title": "Rock Concert", "start": "November 7, 2018 6:30 PM", "end": "November 7, 2018 11:00 PM"}, {"title": "Lunch Meeting", "start": "November 9, 2018 12:30 PM", "end": "November 9, 2018 2:30 PM"}, {"title": "Bicycling with Friends", "start": "November 1, 2018 6:00 AM", "end": "November 1, 2018 9:30 AM"}, {"title": "Birthday Party", "start": "November 10, 2018 12:30 PM", "end": "November 10, 2018 8:30 PM"}, {"title": "Football Tailgate with John", "start": "November 3, 2018 6:14 PM", "end": "November 3, 2018 9:44 PM"}]   

I'm new to swift and I'm wondering how to deal with this

Answer 1

Considering this is a follow up question from your previous post. You can use Swift DateInterval initialiser to create a DateInverval with your start and end dates and check if they intersects with each other:

extension Event {
    var interval: DateInterval { .init(start: start, end: end) }
    func intersects(with event: Event) -> Bool { interval.intersects(event.interval) }
}

---

To check for conflicting events you would need to make your Event conform to Equatable and filter the ones that intersects with them but are not the same event:

struct Event: Codable, Equatable {
    let title: String
    let start: Date
    let end: Date
}

---

let decoder = JSONDecoder()
decoder.dateDecodingStrategy = .monthDayYearTime
do {
    let events = try decoder.decode([Event].self, from: Data(json.utf8))
    print(events.sorted())
    let conflictingEvents: [(Event, Event)] = events.compactMap {
        for event in events where event != $0 {
            if event.intersects(with: $0) && $0.end != event.start && event.end != $0.start { return ($0, event) }
        }
        return nil
    }
    print(events.count)             // "21\n"
    print(conflictingEvents.count)  // "11\n"
} catch {
    print(error)
}