Swift: the correct way to initialize a model class with many properties

Question

Swift: the correct way to initialize a model class with many properties

How do you initialize your classes / structures with more properties?

This question could be asked without a Swift context, but Swift brings it a taste, so I add the Swift tag to the title and tags.

Say you have a class Userwith 20 properties. Most of them should be neither empty nor empty. Suppose that these properties are not interdependent. Suppose that 33% of them should be constant ( let) according to the logic of the class. Assume that at least 65% of them do not have meaningful defaults. How would you create this class and initialize its instance?

I still have few thoughts, but none of this seems to me quite satisfactory:

put all the properties linearly in the class and make a huge init method:

class User {
    // there is 20 properties like that
    let id : String
    let username : String
    let email : String
    ...
    var lastLoginDate : Date
    var lastPlayDate : Date

    // then HUUUUGE init
    init(id: String, 
         username: String,
         ...
         lastPlayDate: Date) {
    }
}

try to group properties into subtypes and handle smaller values separately

class User {
    struct ID {
        let id : String
        let username : String
        let email : String
    }
    struct Activity {
        var lastLoginDate : Date
        var lastPlayDate : Date 
    }
    let id : ID
    ...
    var lastActivity : Activity

    // then not so huge init
    init(id: ID, 
         ...
         lastActivity: Activity) {
    }
}

another solution is to break the requirements a bit: either declare some of the optional properties, or set values after initialization, or declare dummy defaults and set normal values after init, which conceptually looks the same

class User {
    // there is 20 properties like that
    let id : String
    let username : String
    let email : String
    ...
    var lastLoginDate : Date?
    var lastPlayDate : Date?

    // then not so huge init
    init(id: String, 
         username: String,
         email: String) {
    }
}

// In other code 
var user = User(id: "1", username: "user", email: "user@example.com"
user.lastLoginDate = Date()