@inherits LocalizableComponentBase @* The administrators' announcements shown now (/api/v1/announcements) that the persona has not dismissed, one at a time above the feed's tabs: their words (sanitized HTML from the administrator's Markdown), when they run, and the reactions personas left, which the persona adds and takes back with a unicode emoji or one of the server's custom ones (EmojiPicker; its text shows the custom emoji it names). Dismissed, one is gone for this persona. New, changed and removed ones, and the reactions' counts, come through the user stream (StreamingService.HearAnnouncements); the banner renders itself and never touches the feed's cards. *@ @if (Current is { } current) {

@Localizer["Announcement"] @current.PublishedAt.GetPassedTime(Localizer) @if (ShownCount > 1) { @Localizer["{0} of {1}", index + 1, ShownCount] }

@if (current.StartsAt is not null || current.EndsAt is not null) {

@When(current)

}

@((MarkupString)CustomEmojis.Html(current.Content, current.Emojis))

@foreach (var reaction in current.Reactions) { @if (reaction.Url is { Length: > 0 } image) { @NameOf(reaction)

} else { @reaction.Name } @reaction.Count }

} @code { static readonly string[] QuickReactions = ["👍", "❤️", "😂", "🎉", "🔥", "😮", "😢"]; [Inject] AnnouncementService AnnouncementService { get; set; } [Inject] StreamingService Streaming { get; set; } [Inject] EmojiService EmojiService { get; set; } List announcements = []; int index; bool isActing; string loadedPersonaId; // a custom emoji's reaction is named by its shortcode static string NameOf(AnnouncementReaction reaction) => reaction.Url is { Length: > 0 } ? $":{reaction.Name}:" : reaction.Name; // what the persona has not dismissed, oldest first as the server lists them List Shown => [.. announcements.Where(a => a.Read != true)]; int ShownCount => announcements.Count(a => a.Read != true); // the one in view, or none Announcement Current => Shown is [_, ..] shown ? shown[Math.Clamp(index, 0, shown.Count - 1)] : null; protected override void OnInitialized() => Streaming.Announced += OnAnnounced; // another persona reads its own: its dismissals and reactions protected override async Task OnParametersSetAsync() { if (CascadingState.PersonaId is null || CascadingState.PersonaId == loadedPersonaId) return; loadedPersonaId = CascadingState.PersonaId; if (CascadingState.IsOffline) { WhenOnline(LoadData); StartOnlinePolling(); IsLoading = false; return; } await LoadData(); IsLoading = false; } async Task LoadData() { announcements = await AnnouncementService.List(); index = 0; await Streaming.HearAnnouncements(true); } string When(Announcement announcement) { var format = announcement.AllDay ? SUtility.dateTimeFormat : SUtility.dateTimeFormatExt; var starts = announcement.StartsAt?.ToLocalTime().ToString(format); var ends = announcement.EndsAt?.ToLocalTime().ToString(format); return (starts, ends) switch { ({ } from, { } to) => Localizer["From {0} to {1}", from, to], ({ } from, null) => Localizer["From {0}", from], _ => Localizer["until {0}", ends] }; } async Task Dismiss() { if (Current is not { } announcement) return; isActing = true; var result = await AnnouncementService.Dismiss(announcement.Id); isActing = false; if (result.IsInvalid) { Toast.AddResponseError(result); return; } announcement.Read = true; index = Math.Clamp(index, 0, Math.Max(0, ShownCount - 1)); } // the counts are read again afterwards: the stream may have told of this very reaction already async Task React(string emoji, bool add) { if (Current is not { } announcement) return; isActing = true; var result = await AnnouncementService.React(announcement.Id, emoji, add); if (result.IsInvalid) { isActing = false; Toast.AddResponseError(result); return; } var position = index; announcements = await AnnouncementService.List(); index = Math.Clamp(position, 0, Math.Max(0, ShownCount - 1)); isActing = false; } Task OnAnnounced(AnnouncementMessage message) => InvokeAsync(() => { switch (message.Event) { case "announcement" when message.Announcement is { } changed: var at = announcements.FindIndex(a => a.Id == changed.Id); if (at < 0) announcements.Add(changed); else announcements[at] = changed; break; case "announcement.delete" when message.DeletedId is { } id: announcements.RemoveAll(a => a.Id == id); break; case "announcement.reaction" when message.Reaction is { } reaction && announcements.Find(a => a.Id == reaction.AnnouncementId) is { } reacted: var known = reacted.Reactions.Find(r => r.Name == reaction.Name); reacted.Reactions = reaction.Count <= 0 ? [.. reacted.Reactions.Where(r => r.Name != reaction.Name)] : known is null ? [.. reacted.Reactions, NewReaction(reaction)] : [.. reacted.Reactions.Select(r => r.Name == reaction.Name ? new AnnouncementReaction { Name = r.Name, Count = reaction.Count, Me = r.Me, Url = r.Url, StaticUrl = r.StaticUrl } : r)]; break; default: return; } index = Math.Clamp(index, 0, Math.Max(0, ShownCount - 1)); StateHasChanged(); }); // one the stream tells of first: the event names it only, so a custom emoji's pictures come from the server's emoji read // already (none while they aren't, until the list is read again) AnnouncementReaction NewReaction(AnnouncementReactionEvent reaction) => EmojiService.Known(reaction.Name) is { } custom ? new AnnouncementReaction { Name = reaction.Name, Count = reaction.Count, Me = false, Url = custom.Url, StaticUrl = custom.StaticUrl } : new AnnouncementReaction { Name = reaction.Name, Count = reaction.Count, Me = false }; public override async ValueTask DisposeAsync() { Streaming.Announced -= OnAnnounced; await Streaming.HearAnnouncements(false); await base.DisposeAsync(); } }