@inherits LocalizableComponentBase

@* The feed page's tabs, one per kind of feed, scrolling sideways on narrow screens. Groups adds a choice of the
   persona's communities and circles, Lists a choice of its lists (made and filled on /lists), Tag the hashtag being
   read, with its week and a button to follow it (its public posts then come home). The stats icon shows how the current feed was
   read; the buttons on the right open the composer and, on narrow screens, the globe. *@
<div class="flex flex-col gap-2">
	<div class="flex items-center gap-2 min-w-0">
		<div class="flex-1 min-w-0 overflow-x-auto">
			<DTabs Active="ActiveIndex" ActiveChanged="Select" Variant="DTabsVariant.Box" Size="DSize.Sm" ContentClass="hidden" class="flex-nowrap w-max">
				@foreach (var type in Types)
				{
					<DTab Class="gap-1 whitespace-nowrap">
						<Header>
							<i class="@type.GetTimelineTypeIcon()" aria-hidden="true"></i>
							<span class="@(type == Filter.TimelineType ? null : "hidden xl:inline")">@TabName(type)</span>
						</Header>
					</DTab>
				}
			</DTabs>
		</div>
		<NerdTip Heading="@Localizer["Feed"]" Rows="Stats" Placement="DTooltipPlacement.Bottom" Align="DTooltipAlign.End">
			<i class="ion-md-stats opacity-50" aria-label="@Localizer["Feed"]"></i>
		</NerdTip>
		<DButton Size="DSize.Sm" class="lg:hidden" Active="Filter.ShowGlobe" OnClick="ToggleGlobe" title="@Localizer["Globe"]">
			<i class="ion-md-planet text-base"></i>
		</DButton>
		<DButton Size="DSize.Sm" Active="IsComposing" OnClick="() => OnCompose.InvokeAsync()" title="@Localizer["Post"]">
			<i class="ion-md-create text-base"></i>
			<span class="hidden sm:inline">@Localizer["Post"]</span>
		</DButton>
	</div>

	@if (Filter.TimelineType is TimelineType.Groups)
	{
		@if (Groups.Count == 0)
		{
			<p class="text-xs opacity-70">@Localizer["This persona is in no community or circle yet."]</p>
		}
		else
		{
			<DSelect TValue="string" Size="DSize.Sm" class="w-full sm:w-auto" Value="Filter.GroupId" ValueChanged="SelectGroup" ValueExpression="() => Filter.GroupId">
				<Prefix><i class="@(SelectedGroup?.IsCommunity == false ? "ion-md-lock" : "ion-md-contacts")"></i></Prefix>
				<ChildContent>
					@foreach (var group in Groups)
					{
						<option value="@group.Id">@(group.IsCommunity ? "◎" : "◉") @(group.Name ?? group.UserName)</option>
					}
				</ChildContent>
			</DSelect>
		}
	}
	else if (Filter.TimelineType is TimelineType.Lists)
	{
		<div class="flex flex-wrap items-center gap-2">
			@if (Lists.Count == 0)
			{
				<p class="text-xs opacity-70">@Localizer["This persona has no list yet."]</p>
			}
			else
			{
				<DSelect TValue="string" Size="DSize.Sm" class="w-full sm:w-auto" Value="Filter.ListId" ValueChanged="SelectList" ValueExpression="() => Filter.ListId">
					<Prefix><i class="ion-md-list"></i></Prefix>
					<ChildContent>
						@foreach (var list in Lists)
						{
							<option value="@list.Id">@list.Title</option>
						}
					</ChildContent>
				</DSelect>
			}
			<a class="btn btn-sm" href="lists"><i class="ion-md-create"></i><span>@Localizer["Manage lists"]</span></a>
		</div>
	}
	else if (Filter.TimelineType is TimelineType.Tag)
	{
		<div class="flex flex-wrap items-center gap-2 text-sm">
			<i class="ion-md-pricetag"></i><b>#@Filter.Tag</b>
			@if (tag is not null)
			{
				<span class="text-xs opacity-70 tabular-nums">@Localizer["{0} posts this week, {1} people today", tag.WeekUses, tag.TodayAccounts]</span>
				<DButton Size="DSize.Xs" Color="@(tag.Following == true ? DColor.Neutral : DColor.Primary)" Disabled="@(IsDefaultDisabled || isFollowing)"
						 OnClick="ToggleTagFollow" data-tag-follow>
					<span>@(tag.Following == true ? Localizer["Stop following #{0}", tag.Name] : Localizer["Follow #{0}", tag.Name])</span>
				</DButton>
			}
		</div>
	}
</div>

@code {
	[Parameter, EditorRequired] public FeedFilter Filter { get; set; }
	[Parameter] public List<ViewGroup> Groups { get; set; } = [];
	[Parameter] public List<MastodonList> Lists { get; set; } = [];
	[Parameter] public IEnumerable<NerdRow> Stats { get; set; } = [];
	[Parameter] public bool IsComposing { get; set; }
	[Parameter] public EventCallback OnCompose { get; set; }
	/// <summary>Raised after Filter changed (tab, group or globe).</summary>
	[Parameter] public EventCallback<FeedFilter> OnChanged { get; set; }

	static readonly TimelineType[] Always =
	[
		TimelineType.Home, TimelineType.Local, TimelineType.Federation, TimelineType.Nearby, TimelineType.Groups, TimelineType.Direct,
		TimelineType.Notifications, TimelineType.Favourites, TimelineType.Bookmarks, TimelineType.Lists
	];

	List<TimelineType> Types => Filter.Tag is { Length: > 0 } ? [.. Always, TimelineType.Tag] : [.. Always];

	int ActiveIndex => Types.IndexOf(Filter.TimelineType);

	ViewGroup SelectedGroup => Groups.FirstOrDefault(g => g.Id == Filter.GroupId);

	[Inject] DiscoveryService DiscoveryService { get; set; }

	Tag tag;
	string loadedTag;
	bool isFollowing;

	protected override void OnInitialized() => IsLoading = false;

	// the hashtag being read: its week and whether the persona follows it, read again when it changes
	protected override async Task OnParametersSetAsync()
	{
		var wanted = Filter.TimelineType is TimelineType.Tag ? Filter.Tag : null;
		if (wanted == loadedTag)
			return;
		loadedTag = wanted;
		tag = wanted is { Length: > 0 } ? await DiscoveryService.Tag(wanted) : null;
	}

	async Task ToggleTagFollow()
	{
		isFollowing = true;
		var result = await DiscoveryService.FollowTag(tag.Name, tag.Following != true);
		isFollowing = false;
		if (result.IsInvalid)
		{
			Toast.AddResponseError(result);
			return;
		}

		tag = (Tag)result.Data;
		Toast.AddResponseSuccess(tag.Following == true ? Localizer["Following #{0}: its public posts come home.", tag.Name] : Localizer["No longer following #{0}.", tag.Name]);
	}

	string TabName(TimelineType type) => type switch
	{
		TimelineType.Federation => Localizer["Federated"],
		TimelineType.Tag => "#" + Filter.Tag,
		_ => Localizer[type.ToString()]
	};

	async Task Select(int index)
	{
		Filter.TimelineType = Types[index];
		if (Filter.TimelineType is TimelineType.Groups && SelectedGroup is null)
			Filter.GroupId = Groups.FirstOrDefault()?.Id;
		if (Filter.TimelineType is TimelineType.Lists && Lists.All(l => l.Id != Filter.ListId))
			Filter.ListId = Lists.FirstOrDefault()?.Id;
		await OnChanged.InvokeAsync(Filter);
	}

	async Task SelectList(string listId)
	{
		Filter.ListId = listId;
		await OnChanged.InvokeAsync(Filter);
	}

	async Task SelectGroup(string groupId)
	{
		Filter.GroupId = groupId;
		await OnChanged.InvokeAsync(Filter);
	}

	async Task ToggleGlobe()
	{
		Filter.ShowGlobe = !Filter.ShowGlobe;
		await OnChanged.InvokeAsync(Filter);
	}
}