import android.content.Context
import android.os.Parcelable
import java.util.*



open class DbProxy constructor(val context: Context) {

    private val db: PodcastDatabaseHelper

    init {
        db = PodcastDatabaseHelper(context)
        db.writableDatabase // call for first initialization
    }

    // ...

    @Synchronized
    fun insertOrUpdatePodcast(podcastItem: PodcastDatabaseItem,
                              keepCurrentPlayProgress: Boolean) {
        val itemInDatabase = findByMp3Url(podcastItem.url)

        if (itemInDatabase != null) {
            updateItem(itemInDatabase, podcastItem, keepCurrentPlayProgress)
        } else {
            insertItem(podcastItem)
        }
    }

    // ...

}

data class PodcastDatabaseItem(
        val url: String,
        val publishedDate: Date,
        var title: String,
        var description: String,
        var progress: Int,
        var duration: Int,
        var speed: Float,
        var filePath: String) : Parcelable {

    // ...

}