protected override void OnResetItems(IEnumerable <PlaylistItem> sourceItems, PlaylistItem item)
{
var copied = sourceItems.ToList();
// 再生済みアイテムを同期
var existPlayedItems = PlayedItem.Where(x => copied.Any(y => y.ContentId == x.ContentId));
PlayedItem = new Stack <PlaylistItem>(existPlayedItems);
// ランダム化したアイテムの同期
RandamizedItems.Clear();
var shuffledUnplayItems = copied
.Where(x => !PlayedItem.Any(y => x.ContentId == y.ContentId))
.Shuffle();
foreach (var shuffled in shuffledUnplayItems)
{
RandamizedItems.Enqueue(shuffled);
}
// Currentを同期
// 現在再生中のアイテムが削除されていた場合、Currentをnullにするだけ
if (Current != null && !copied.Any(x => x.ContentId == Current.ContentId))
{
Current = null;
}
}
protected override PlaylistItem GetPreviousItem_Inner()
{
// Playedから１つ取り出して
// Randomizedに載せる
var prevItem = PlayedItem.Pop();
if (Current != null && prevItem != null)
{
RandamizedItems.Enqueue(Current);
return(prevItem);
}
else
{
throw new Exception();
}
}