User_v6.swift

struct User: Codable {
	typealias Id = String
	
	let id: Id
	let cellNumber: CellNumber
	let status: Status
	
	
	enum Status {
		case notRegistered
		case registered(profile: Profile)
	}
	
	struct Profile: Codable {
		let name: String
		let lastName: String
		let email: Email?
		let isEmailVerified: Bool
		
		private enum CodingKeys: String, CodingKey {
			case name
			case lastName = "last_name"
			case email
			case isEmailVerified = "is_email_verified"
		}
	}
	
	private enum CodingKeys: String, CodingKey {
		case id
		case cellNumber = "cell_number"
		case isRegistered = "is_registered"
		case profile
	}
	
	init(from decoder: Decoder) throws {
		let container = try decoder.container(keyedBy: CodingKeys.self)
		id = try container.decode(Id.self, forKey: .id)
		cellNumber = try container.decode(CellNumber.self, forKey: .cellNumber)
		let isRegistered = try container.decode(Bool.self, forKey: .isRegistered)
		status = isRegistered ? try .registered(profile: container.decode(Profile.self, forKey: .profile)) : .notRegistered
	}
	
	func encode(to encoder: Encoder) throws {
		var container = encoder.container(keyedBy: CodingKeys.self)
		try container.encode(id, forKey: .id)
		try container.encode(cellNumber, forKey: .cellNumber)
		switch status {
		case .notRegistered:
			try container.encode(false, forKey: .isRegistered)
		case .registered(let profile):
			try container.encode(true, forKey: .isRegistered)
			try container.encode(profile, forKey: .profile)
		}
	}
}

struct CellNumber: Codable {
	let digits: String
	
	init(from decoder: Decoder) throws {
		let container = try decoder.singleValueContainer()
		let rawDigits = try container.decode(String.self)
		// validate rawDigits by some Regex maybe? and throw appropriate errors?
		// or extract CountryCode and AreaCode and save them in another way?
		self.digits = rawDigits
	}
	
	func encode(to encoder: Encoder) throws {
		var container = encoder.singleValueContainer()
		try container.encode(digits)
	}
}

struct Email: Codable {
	let address: String
	
	init(from decoder: Decoder) throws {
		let container = try decoder.singleValueContainer()
		let rawAddress = try container.decode(String.self)
		// validate rawAddress by some Regex maybe? and throw appropriate errors?
		self.address = rawAddress
	}
	
	func encode(to encoder: Encoder) throws {
		var container = encoder.singleValueContainer()
		try container.encode(address)
	}
}

// MARK:- User Helper methods
extension User {
	var isRegistered: Bool {
		return status.isRegistered
	}
	
	var profile: Profile? {
		return status.profile
	}
}

// MARK:- User.Status helper methods
extension User.Status {
	fileprivate var isRegistered: Bool {
		switch self {
		case .registered: return true
		case .notRegistered: return false
		}
	}
	
	fileprivate var profile: User.Profile? {
		switch self {
		case .registered(let profile): return profile
		case .notRegistered: return nil
		}
	}
}