/// <summary>
/// Serializes the provided instance of <paramref name="embedMetadata"/> and returns an updated version of <paramref name="uri"/>
/// that contains the serialized string in the URI fragment.
/// </summary>
static private string StealthInto(string uri, IEmbedMetadata embedMetadata)
{
var oldUri = new Uri(uri);
var existingFragmentData = HttpUtility.ParseQueryString(oldUri.Fragment);
var newFragment = SerializeMetadata(embedMetadata, existingFragmentData);
var newUriBuilder = new UriBuilder(uri)
{
Fragment = newFragment
};
return(newUriBuilder.ToString());
}
/// <summary>
/// Serializes the provided instance of <paramref name="embedMetadata"/> into a URL query string-ish representation.
/// </summary>
static private string SerializeMetadata(IEmbedMetadata embedMetadata, NameValueCollection existingFragmentData = null)
{
var fragmentData = existingFragmentData ?? new NameValueCollection();
var fragmentDict = new Dictionary <string, string>();
// Update it with the required values
embedMetadata.SaveInto(fragmentDict);
foreach (var(key, value) in fragmentDict)
{
fragmentData[key] = value;
}
fragmentData["_k"] = embedMetadata.EmbedKind;
// Make a list of query pairs
var keyValuePairs = new List <string>();
foreach (var key in fragmentData.AllKeys.OrderBy(k => k, StringComparer.OrdinalIgnoreCase))
{
keyValuePairs.Add(Escape(key) + "=" + Escape(fragmentData[key]));
}
return(string.Join("&", keyValuePairs));
}
/// <summary>
/// <para>Adjusts the embed under construction so that it includes recoverable representation of <paramref name="embedMetadata"/>.</para>
/// <para>For optimal results, call this method after <see cref="EmbedBuilder.WithAuthor"/> or <see cref="EmbedBuilder.WithImageUrl"/>.</para>
/// </summary>
/// <param name="embedBuilder"></param>
/// <param name="embedMetadata">The metadata to store inside the embed.</param>
/// <returns></returns>
static public EmbedBuilder WithMetadata(this EmbedBuilder embedBuilder, IEmbedMetadata embedMetadata)
{
if (embedBuilder.Author?.IconUrl is string authorIconUrl)
{
authorIconUrl = StealthInto(authorIconUrl, embedMetadata);
return(embedBuilder.WithAuthor(embedBuilder.Author.Name, authorIconUrl, embedBuilder.Author.Url));
}
else if (embedBuilder.ImageUrl is string imageUrl)
{
imageUrl = StealthInto(imageUrl, embedMetadata);
return(embedBuilder.WithImageUrl(imageUrl));
}
else
{
var metadataText = SerializeMetadata(embedMetadata);
var oldFooterText = embedBuilder.Footer.Text;
if (!string.IsNullOrEmpty(oldFooterText))
{
oldFooterText = " " + oldFooterText;
}
return(embedBuilder.WithFooter(metadataText + oldFooterText));
}
}
