Swift decodable propagate userInfo - ios

Question

I have the following models:
struct Shop: Decodable {
let id: Int
let name: String
let products: [Product]
private enum CodingKeys: String, CodingKey {
case id
case name
case products
}
init(from decoder: Decoder) throws {
let container = try decoder.container(keyedBy: CodingKeys.self)
self.id = try container.decode(Int.self, forKey: .id)
self.name = try container.decode(String.self, forKey: .name)
self.products = try container.decode([Product].self, forKey: .products)
}
}
struct Product: Decodable {
let id: Int
let title: String
let productImageURL: String
private(set) var productDetails: ProductDetails
private enum CodingKeys: String, CodingKey {
case id
case title
case productImageList
case productImageDetails
case productDetails
}
init(from decoder: Decoder) throws {
let container = try decoder.container(keyedBy: CodingKeys.self)
self.id = try container.decode(Int.self, forKey: .id)
self.title = try container.decode(String.self, forKey: .title)
self.productDetails = try container.decode(ProductDetails.self, forKey: .productDetails)
guard let serializationType = decoder.userInfo[.serializationType] as? SerializationGenericType else {
throw NetworkError.modelParsingError(message: "Product model missing serialization type")
}
switch serializationType {
case .list:
self.productImageURL = try container.decode(String.self, forKey: .productImageList)
case .details:
self.productImageURL = try container.decode(String.self, forKey: .productImageList)
self.productDetails = try container.decode(ProductDetails.self, forKey: .productDetails)
}
}
}
Of course, the models are much more complex, but this is enough to explain my problem :)
Also, please don't mind the coding keys and the image URL, it's just to show that for different serialization type it initialized differently.
When getting the product details I have:
let decoder = JSONDecoder()
decoder.userInfo[.serializationType] = SerializationGenericType.details
let product = try decoder.decode(Product.self, from: data)
But when I try to pass the serialization type when initializing the Shop in the user info of the JsonDecoder like this:
let decoder = JSONDecoder()
decoder.userInfo[.serializationType] = SerializationGenericType.list
let shop = try decoder.decode(Shop.self, from: data)
In the Product initializer the user info is empty.
My question is how to propagate the serialization type from the Shop to the Product so I can properly decode it using the correct serialization type?