Matching separated arrays for Realm Object - swift

Question

I’m stuck with some problem. I have a JSON response from server:
{
"days" : [
{
"id" : 1,
"name" : "Day 1 - first day",
"url": "http://example.com/days/1"
},
{
"id" : 2,
"name" : "Day 2 - second day",
"url": "http://example.com/days/2"
},
...
],
"week" : [
{
"id" : 1,
"dayIds" : [1, 2, 6, 9, 23, 44, 2345],
"name" : "Rest week"
},
{
"id" : 35,
"dayIds" : [34,77,23,67,126,224],
"name" : "Educational week"
},
],
"plan" : {
"weekIds: [1, 6, 23, 74]
}
}
My data models (without mapping):
class Day: Object {
#objc dynamic var id: Int = -1
#objc dynamic var name: String = ""
#objc dynamic var url: String = ""
}
class Week: Object {
var dayIds = List<String>()
#objc dynamic var name: String = ""
#objc dynamic var id: Int = -1
var days: List<Week>? = nil
}
class Plan: Object {
var weekDays = List<String>()
var weeks: List<Week>? = nil
}
Mapping code:
let json: [String: Any] = try! JSONSerialization.jsonObject(with: data, options: .allowFragments) as! [String: Any]
let plans: [Plan] = Mapper<Plan>().mapArray(JSONArray: json["plans"] as! [[String: Any]])
let days: [Day] = Mapper<Day>().mapArray(JSONArray: json["days"] as! [[String: Any]])
let weeks: [Week] = Mapper<Week>().mapArray(JSONArray: json["weeks"] as! [[String: Any]])
So, I need to tell realm that an array weeks belong to plan.weeks and an array days belong to object week.days and related by theirs id’s. How can I do this more simply? Do you have any ideas?
The alternative solution is in-head brute force like this.
for week in weeks {
for dayId in week.dayIds {
for day in days {
if day.id == dayId {
week.days.append(day)
}
}
}
}
for plan in plans {
for week in weeks {
for weekId in plans.weekIds {
if weekId == week.id {
plan.weeks.append(week)
}
}
}
}
I believe that somewhere exist more pure and simple solution :)
Thanks.

Answer 1

Your data structures seem very nested, so you're going to have to do the internal looping. If you want something more swifty, use map and filter here instead of for loops:
let days = weeks.map({
$0.dayIds.map({
$0.filter({
$0.id == dayId
})
})
})