workouts/Workouts Watch App/Models/Workout.swift

import Foundation
import CoreData

@objc(Workout)
public class Workout: NSManagedObject, Identifiable {
    @NSManaged public var start: Date
    @NSManaged public var end: Date?

    @NSManaged public var split: Split?
    @NSManaged public var logs: NSSet?

    public var id: NSManagedObjectID { objectID }

    var status: WorkoutStatus {
        get {
            willAccessValue(forKey: "status")
            let raw = primitiveValue(forKey: "status") as? String ?? "notStarted"
            didAccessValue(forKey: "status")
            return WorkoutStatus(rawValue: raw) ?? .notStarted
        }
        set {
            willChangeValue(forKey: "status")
            setPrimitiveValue(newValue.rawValue, forKey: "status")
            didChangeValue(forKey: "status")
        }
    }

    var label: String {
        if status == .completed, let endDate = end {
            if start.isSameDay(as: endDate) {
                return "\(start.formattedDate())—\(endDate.formattedTime())"
            } else {
                return "\(start.formattedDate())—\(endDate.formattedDate())"
            }
        } else {
            return start.formattedDate()
        }
    }

    var statusName: String {
        return status.displayName
    }
}

// MARK: - Convenience Accessors

extension Workout {
    var logsArray: [WorkoutLog] {
        let set = logs as? Set<WorkoutLog> ?? []
        return set.sorted { $0.order < $1.order }
    }

    func addToLogs(_ log: WorkoutLog) {
        let items = mutableSetValue(forKey: "logs")
        items.add(log)
    }

    func removeFromLogs(_ log: WorkoutLog) {
        let items = mutableSetValue(forKey: "logs")
        items.remove(log)
    }
}

// MARK: - Fetch Request

extension Workout {
    @nonobjc public class func fetchRequest() -> NSFetchRequest<Workout> {
        return NSFetchRequest<Workout>(entityName: "Workout")
    }

    static func recentFetchRequest() -> NSFetchRequest<Workout> {
        let request = fetchRequest()
        request.sortDescriptors = [NSSortDescriptor(keyPath: \Workout.start, ascending: false)]
        return request
    }

    static func fetchRequest(for split: Split) -> NSFetchRequest<Workout> {
        let request = fetchRequest()
        request.predicate = NSPredicate(format: "split == %@", split)
        request.sortDescriptors = [NSSortDescriptor(keyPath: \Workout.start, ascending: false)]
        return request
    }
}