migration_ios.kt

actual fun getNonEncryptedSettings(context: AppContext?): Settings =
    NSUserDefaultsSettings(NSUserDefaults.standardUserDefaults)

@OptIn(ExperimentalSettingsImplementation::class)
actual fun getEncryptedSettings(context: AppContext?): Settings =
    MigrationSettings(
        listOf("key1", "key2"),
        getNonEncryptedSettings(context),
        KeychainSettings("${NSBundle.mainBundle.bundleIdentifier}.AUTH")
    )

@OptIn(ExperimentalSettingsImplementation::class)
private class MigrationSettings(
    keysToMigrate: List<String>,
    oldSettings: Settings,
    val keychainSettings: KeychainSettings
) : Settings by keychainSettings {

    init {
        keysToMigrate.forEach { key ->
            val value = oldSettings.getStringOrNull(key)
            value?.let {
                putString(key, it)
                oldSettings.remove(key)
            }
        }
    }
}