public async IAsyncEnumerable <R4UCard> Process(IAsyncEnumerable <R4UCard> originalCards)
{
await foreach (var card in originalCards)
{
yield return(card);
Log.Information("Getting possible foils for [{serial}]", card.Serial);
var urlRequest = new FlurlRequest(foilSearchURL).SetQueryParam("keyword", card.Serial);
Log.Debug("URL: {url}", urlRequest.Url);
var doc = await urlRequest.GetHTMLAsync();
var cardList = doc.QuerySelectorAll(".cardlist-item").Select(i => i as IHtmlAnchorElement).Skip(1);
foreach (var cardLink in cardList)
{
Log.Information("Found URL: {url}", cardLink.Href);
var cardLinkDoc = await cardLink.Href.WithReferrer(urlRequest.Url.Path).GetHTMLAsync();
var newCard = card.Clone();
newCard.NonFoil = card;
newCard.Serial = cardLinkDoc.QuerySelector(".cardlist-number").TextContent;
newCard.Rarity = cardLinkDoc.QuerySelectorAll(".cardlist-text") //
.Where(i => i.Children.ElementAt(2)?.TextContent == "レアリティ")
.Select(i => i.Children.ElementAt(3).TextContent.Trim())
.First();
yield return(newCard);
}
}
}