svelte-kit-vice/web/routes/uix/components/feed/+page.svelte

<script lang="ts">
	import {
		Feed,
		type FeedSize,
		type FeedVariant,
		type FeedColor
	} from '$uix/eidos/components/feed';
	import { Button } from '$uix/eidos/components/button';
	import { compileMorfo } from '$uix/morfo';
	import { feedMorfo } from '@/uix/morfo/components/feed';
	import { getActiveUix } from '$active-uix';

	const uix = getActiveUix();

	type Tab = 'live' | 'api' | 'morfo' | 'sema' | 'recipe' | 'a11y';
	let tab = $state<Tab>('live');

	// ── Sample data ──────────────────────────────────────────────────────
	type Reply = { id: string; author: string; body: string };
	type Post = { id: string; title: string; body: string; replies?: Reply[] };

	const SEED: Post[] = [
		{ id: 'p1', title: 'Shipped soma TreeGrid', body: 'Hierarchical rows + columns over CSS grid. RowChildren span 1/-1 to keep alignment.', replies: [
			{ id: 'r1', author: 'Ada', body: 'Nice — does it cope with deeply nested levels?' },
			{ id: 'r2', author: 'Ben', body: 'Caps at 8 in the recipe, deeper trees override the indent var.' }
		] },
		{ id: 'p2', title: 'Auto-derived heading level for threads', body: 'Top-level articles are h3, nested h4, double-nested h5. Aria-level matches.' },
		{ id: 'p3', title: 'PageDown at the end fires onLoadMore', body: 'No JS scroll listener needed — the Provider intercepts keydown on focused articles.' },
		{ id: 'p4', title: 'IntersectionObserver sentinel', body: 'Drop a Sentinel inside the Feed. When it scrolls into view, onIntersect fires.', replies: [
			{ id: 'r3', author: 'Cora', body: 'Defaults to the Feed\'s onLoadMore — works out of the box.' }
		] }
	];

	let posts = $state<Post[]>(SEED);
	let busy = $state(false);
	let totalItems = $state<number | undefined>(undefined);
	let useSentinel = $state(true);

	function loadMore() {
		if (busy) return;
		busy = true;
		setTimeout(() => {
			const nextId = posts.length + 1;
			posts = [
				...posts,
				{
					id: `p${nextId}`,
					title: `Lazy-loaded post #${nextId}`,
					body: `Sentinel-triggered article ${nextId}. ${busy ? 'busy' : 'idle'}.`
				}
			];
			busy = false;
		}, 600);
	}

	// ── Visual props ─────────────────────────────────────────────────────
	let size = $state<FeedSize>('md');
	let variant = $state<FeedVariant>('surface');
	let color = $state<FeedColor>('primary');
	let block = $state(true);
	let useScrollRegion = $state(false);

	// ── i18n ─────────────────────────────────────────────────────────────
	let locale = $state('en-US');
	let dir = $state<'ltr' | 'rtl'>('ltr');

	const compiled = compileMorfo(feedMorfo);
	const partsList = $derived([...compiled.parts.byKebab.values()]);
	const events = $derived([...compiled.actions.byName.values()]);

	type TraceEntry = { event: string; family: string; intent?: string; at: number };
	let trace = $state<TraceEntry[]>([]);
	let stageRef = $state<HTMLElement | null>(null);

	$effect(() => {
		const el = stageRef;
		if (!el) return;
		const obs = new MutationObserver((mutations) => {
			for (const m of mutations) {
				if (m.attributeName !== 'data-event') continue;
				const target = m.target as Element;
				const ev = target.getAttribute('data-event');
				if (!ev) continue;
				trace = [
					{
						event: ev,
						family: target.getAttribute('data-event-family') ?? '—',
						intent: target.getAttribute('data-event-intent') ?? undefined,
						at: Date.now()
					},
					...trace
				].slice(0, 6);
			}
		});
		obs.observe(el, { attributes: true, subtree: true, attributeFilter: ['data-event'] });
		return () => obs.disconnect();
	});

	function fmtTime(at: number): string {
		const d = new Date(at);
		return `${String(d.getSeconds()).padStart(2, '0')}.${String(d.getMilliseconds()).padStart(3, '0')}`;
	}

	const eidosSnippet = $derived(
		[
			"<script lang='ts'>",
			"  import { Feed } from '$uix/eidos/components/feed';",
			'  let posts = $state<Post[]>([]);',
			'  let busy = $state(false);',
			'  function loadMore() { /* fetch next page */ }',
			'</' + 'script>',
			'',
			'<Feed',
			'  {busy}',
			'  onLoadMore={loadMore}',
			dir !== 'ltr' && `  dir="${dir}"`,
			totalItems !== undefined && `  totalItems={${totalItems}}`,
			size !== 'md' && `  size="${size}"`,
			variant !== 'surface' && `  variant="${variant}"`,
			color !== 'primary' && `  color="${color}"`,
			!block && '  block={false}',
			useScrollRegion && '  maxHeight="24rem"',
			'>',
			'  {#each posts as post (post.id)}',
			'    <Feed.Article>',
			'      <Feed.ArticleTitle>{post.title}</Feed.ArticleTitle>',
			'      <Feed.ArticleDescription>{post.body}</Feed.ArticleDescription>',
			'    </Feed.Article>',
			'  {/each}',
			useSentinel && '  <Feed.Sentinel />',
			'</Feed>'
		]
			.filter(Boolean)
			.join('\n')
	);
</script>

<div data-uix-canvas-inner {dir}>
	<header>
		<div data-uix-eyebrow>Data · Feed</div>
		<h1 data-uix-page-title>Feed</h1>
		<p data-uix-page-lede>
			Scrollable activity stream — <code>role="feed"</code> of
			<code>role="article"</code> children. PageUp/PageDown navigates
			articles; the Sentinel fires <code>onLoadMore</code> when it
			scrolls into view. Use Feed for activity streams, chat
			histories, threaded comments — anything where the article
			count grows lazily. Use <code>GridList</code> /
			<code>Listbox</code> for bounded selection.
		</p>
		<div data-uix-page-meta>
			<span data-uix-meta-pill>
				<span data-uix-meta-key>parts</span>{compiled.parts.order.length}
			</span>
			<span data-uix-meta-pill>
				<span data-uix-meta-key>events</span>{events.length}
			</span>
			<span data-uix-meta-pill>
				<span data-uix-meta-key>sizes</span>5
			</span>
			<span data-uix-meta-pill>
				<span data-uix-meta-key>apg</span>
				<a href={feedMorfo.apg} target="_blank" rel="noreferrer">feed ↗</a>
			</span>
			<span data-uix-meta-pill>
				<span data-uix-meta-key>posts</span> {posts.length}
			</span>
			<span data-uix-meta-pill>
				<span data-uix-meta-key>busy</span> {busy ? 'loading' : 'idle'}
			</span>
			<span data-uix-meta-pill>
				<span data-uix-meta-key>locale</span> {locale}
			</span>
			<span data-uix-meta-pill>
				<span data-uix-meta-key>dir</span> {dir}
			</span>
		</div>
	</header>

	<div data-uix-stage>
		<div data-uix-stage-area bind:this={stageRef} style="padding: var(--uix-space-3); display: flex; justify-content: center;">
			<div style="inline-size: min(36rem, 100%);">
				<Feed
					{busy}
					{totalItems}
					{dir}
					{size}
					{variant}
					{color}
					{block}
					aria-label="Activity stream"
					maxHeight={useScrollRegion ? '24rem' : undefined}
					onLoadMore={loadMore}
				>
					{#each posts as post (post.id)}
						<Feed.Article>
							<Feed.ArticleTitle>{post.title}</Feed.ArticleTitle>
							<Feed.ArticleDescription>{post.body}</Feed.ArticleDescription>
							{#if post.replies?.length}
								<Feed.Thread>
									{#each post.replies as r (r.id)}
										<Feed.Article>
											<Feed.ArticleTitle>{r.author}</Feed.ArticleTitle>
											<Feed.ArticleDescription>{r.body}</Feed.ArticleDescription>
										</Feed.Article>
									{/each}
								</Feed.Thread>
							{/if}
						</Feed.Article>
					{/each}
					{#if useSentinel}
						<Feed.Sentinel disabled={busy}>
							{busy ? 'Loading more…' : 'Scroll to load more'}
						</Feed.Sentinel>
					{/if}
				</Feed>
			</div>
		</div>
		<div data-uix-stage-trace>
			<span data-uix-stage-trace-key>trace</span>
			{#if trace.length === 0}
				<span>focus an article + PageDown to navigate; scroll to fire sentinel…</span>
			{:else}
				{#each trace.slice(0, 3) as entry}
					<span><span data-uix-stage-trace-event>{entry.event}</span> · {entry.family}{entry.intent ? ' · ' + entry.intent : ''}</span>
					<span style="color: var(--uix-text-faint)">{fmtTime(entry.at)}</span>
				{/each}
			{/if}
			<span style="margin-inline-start: auto;">
				<span data-uix-stage-trace-key>posts</span> {posts.length}
			</span>
		</div>
	</div>

	<div data-uix-tabs role="tablist">
		<button data-uix-tab data-active={tab === 'live'} onclick={() => (tab = 'live')}>Live</button>
		<button data-uix-tab data-active={tab === 'api'} onclick={() => (tab = 'api')}>
			API <span data-uix-tab-count>6</span>
		</button>
		<button data-uix-tab data-active={tab === 'morfo'} onclick={() => (tab = 'morfo')}>
			<span data-uix-layer-badge="morfo">morfo</span>
			<span data-uix-tab-count>{partsList.length}p · {events.length}e</span>
		</button>
		<button data-uix-tab data-active={tab === 'sema'} onclick={() => (tab = 'sema')}>
			<span data-uix-layer-badge="sema">sema</span>
			<span data-uix-tab-count>{events.length}</span>
		</button>
		<button data-uix-tab data-active={tab === 'recipe'} onclick={() => (tab = 'recipe')}>Recipe</button>
		<button data-uix-tab data-active={tab === 'a11y'} onclick={() => (tab = 'a11y')}>A11y</button>
	</div>

	{#if tab === 'live'}
		<section data-uix-section>
			<h2 data-uix-section-title>Controls</h2>
			<p data-uix-section-desc>
				Soma owns PageUp/PageDown nav, Ctrl+Home/End jumps, auto-derived aria-level for threads, IntersectionObserver sentinel wiring. Eidos adds card chrome + thread indent + sentinel spinner.
			</p>

			<div data-uix-subsection-head>
				<span data-uix-layer-badge="soma">soma</span> i18n
			</div>
			<div data-uix-controls>
				<label data-uix-control>
					<span data-uix-control-label>locale</span>
					<select bind:value={locale}>
						<option value="en-US">en-US</option>
						<option value="es-ES">es-ES</option>
						<option value="fr-FR">fr-FR</option>
					</select>
				</label>
				<label data-uix-control>
					<span data-uix-control-label>direction</span>
					<span data-uix-chips role="radiogroup">
						{#each ['ltr', 'rtl'] as v (v)}
							<button data-uix-chip data-active={dir === v} onclick={() => (dir = v as 'ltr' | 'rtl')}>{v}</button>
						{/each}
					</span>
				</label>
			</div>

			<div data-uix-subsection-head>
				<span data-uix-layer-badge="soma">soma</span> feature toggles
			</div>
			<div data-uix-controls>
				<label data-uix-control>
					<span data-uix-control-label>totalItems</span>
					<span data-uix-chips role="radiogroup">
						<button data-uix-chip data-active={totalItems === undefined} onclick={() => (totalItems = undefined)}>unknown</button>
						<button data-uix-chip data-active={totalItems === 20} onclick={() => (totalItems = 20)}>20</button>
						<button data-uix-chip data-active={totalItems === 100} onclick={() => (totalItems = 100)}>100</button>
					</span>
				</label>
				<label data-uix-control>
					<span data-uix-control-label>Sentinel</span>
					<span data-uix-switch>
						<input type="checkbox" bind:checked={useSentinel} />
						<span data-uix-switch-label>{useSentinel ? 'auto-load on scroll' : 'manual'}</span>
					</span>
				</label>
				<label data-uix-control>
					<span data-uix-control-label>busy</span>
					<span data-uix-switch>
						<input type="checkbox" bind:checked={busy} />
						<span data-uix-switch-label>{busy ? 'aria-busy' : 'idle'}</span>
					</span>
				</label>
				<label data-uix-control>
					<span data-uix-control-label>actions</span>
					<span style="display: flex; gap: var(--uix-space-1); align-items: center;">
						<Button size="sm" variant="ghost" onclick={loadMore} disabled={busy}>Load more</Button>
						<Button size="sm" variant="ghost" onclick={() => (posts = SEED)}>Reset</Button>
					</span>
				</label>
			</div>

			<div data-uix-subsection-head>
				<span data-uix-layer-badge="eidos">eidos</span> visual props
			</div>
			<div data-uix-controls>
				<label data-uix-control>
					<span data-uix-control-label>variant</span>
					<span data-uix-chips role="radiogroup">
						{#each ['surface', 'outline', 'ghost'] as v (v)}
							<button data-uix-chip data-active={variant === v} onclick={() => (variant = v as FeedVariant)}>{v}</button>
						{/each}
					</span>
				</label>
				<label data-uix-control>
					<span data-uix-control-label>size</span>
					<span data-uix-chips role="radiogroup">
						{#each ['xs', 'sm', 'md', 'lg', 'xl'] as s (s)}
							<button data-uix-chip data-active={size === s} onclick={() => (size = s as FeedSize)}>{s}</button>
						{/each}
					</span>
				</label>
				<label data-uix-control>
					<span data-uix-control-label>color</span>
					<span data-uix-chips role="radiogroup">
						{#each ['primary', 'secondary', 'neutral', 'affirm', 'fulfill', 'risk', 'threat', 'loss'] as c (c)}
							<button data-uix-chip data-active={color === c} onclick={() => (color = c as FeedColor)}>{c}</button>
						{/each}
					</span>
				</label>
				<label data-uix-control>
					<span data-uix-control-label>block</span>
					<span data-uix-switch>
						<input type="checkbox" bind:checked={block} />
						<span data-uix-switch-label>{block ? 'on' : 'off'}</span>
					</span>
				</label>
				<label data-uix-control>
					<span data-uix-control-label>scrollable</span>
					<span data-uix-switch>
						<input type="checkbox" bind:checked={useScrollRegion} />
						<span data-uix-switch-label>{useScrollRegion ? 'maxHeight=24rem' : 'off'}</span>
					</span>
				</label>
			</div>

			<div data-uix-code>
				<div data-uix-code-head>
					<span data-uix-layer-badge="eidos">eidos</span>
					<span>visual · Feed + Article + Sentinel</span>
					<span data-uix-code-lang>svelte</span>
				</div>
				<pre><code>{eidosSnippet}</code></pre>
			</div>
		</section>
	{/if}

	{#if tab === 'api'}
		<section data-uix-section>
			<h2 data-uix-section-title>API reference</h2>
			<p data-uix-section-desc>6 parts: <code>Provider · Article · ArticleTitle · ArticleDescription · Thread · Sentinel</code>. Provider auto-wires <code>aria-labelledby</code> / <code>aria-describedby</code> on each Article. Thread depth drives auto-derived heading level (h3 → h4 → h5 …).</p>

			<div data-uix-subsection-head>Provider (Feed)</div>
			<div data-uix-table-wrap>
				<table data-uix-table>
					<thead><tr><th>Prop</th><th>Type</th><th>Default</th><th>Description</th></tr></thead>
					<tbody>
						<tr><td class="name">totalItems</td><td class="type">number | undefined</td><td class="default empty">—</td><td>Total across all pages. <code>undefined</code> = unknown (AT reads "n of unknown").</td></tr>
						<tr><td class="name">busy</td><td class="type">boolean</td><td class="default">false</td><td>Sets <code>aria-busy</code> while loading.</td></tr>
						<tr><td class="name">onLoadMore</td><td class="type">() => void</td><td class="default empty">—</td><td>Fired on PageDown-past-last or Sentinel intersection.</td></tr>
						<tr><td class="name">variant <span data-uix-tag data-kind="eidos">eidos</span></td><td class="type">'surface' | 'outline' | 'ghost'</td><td class="default">'surface'</td><td>Article card chrome.</td></tr>
						<tr><td class="name">size <span data-uix-tag data-kind="eidos">eidos</span></td><td class="type">'xs' | 'sm' | 'md' | 'lg' | 'xl'</td><td class="default">'md'</td><td>Padding + thread indent + font scale.</td></tr>
						<tr><td class="name">color <span data-uix-tag data-kind="eidos">eidos</span></td><td class="type">ColorRole</td><td class="default">'primary'</td><td>Focus ring + sentinel spinner.</td></tr>
						<tr><td class="name">block <span data-uix-tag data-kind="eidos">eidos</span></td><td class="type">boolean</td><td class="default">true</td><td>Stretch to container width.</td></tr>
						<tr><td class="name">maxHeight <span data-uix-tag data-kind="eidos">eidos</span></td><td class="type">string</td><td class="default empty">—</td><td>Wraps the feed in a scroll region.</td></tr>
					</tbody>
				</table>
			</div>

			<div data-uix-subsection-head>Article · ArticleTitle · Sentinel</div>
			<div data-uix-table-wrap>
				<table data-uix-table>
					<thead><tr><th>Prop</th><th>Type</th><th>Default</th><th>Description</th></tr></thead>
					<tbody>
						<tr><td class="name">Article.posinset</td><td class="type">number</td><td class="default">auto</td><td>1-based position in full set. Auto when DOM order matches feed order.</td></tr>
						<tr><td class="name">ArticleTitle.level</td><td class="type">1–6</td><td class="default">3 + threadDepth</td><td>Heading level. Auto-derived from enclosing Thread depth.</td></tr>
						<tr><td class="name">Sentinel.rootMargin</td><td class="type">string</td><td class="default">'200px'</td><td>IntersectionObserver rootMargin.</td></tr>
						<tr><td class="name">Sentinel.onIntersect</td><td class="type">() => void</td><td class="default">Feed.onLoadMore</td><td>Defaults to firing the parent Feed's onLoadMore.</td></tr>
						<tr><td class="name">Sentinel.disabled</td><td class="type">boolean</td><td class="default">false</td><td>Skip observer setup.</td></tr>
					</tbody>
				</table>
			</div>
		</section>
	{/if}

	{#if tab === 'morfo'}
		<section data-uix-section>
			<h2 data-uix-section-title>
				<span data-uix-layer-badge="morfo">morfo</span>
				· declarative contract
			</h2>
			<p data-uix-section-desc>Source: <code>src/uix/morfo/components/feed.ts</code>.</p>

			<div data-uix-subsection-head>Parts</div>
			<div data-uix-table-wrap>
				<table data-uix-table>
					<thead><tr><th>Part</th><th>Marker</th><th>Element</th><th>Role</th><th>Archetype</th><th>States</th><th>Optional</th></tr></thead>
					<tbody>
						{#each partsList as part (part.kebab)}
							<tr>
								<td class="name">{part.kebab}</td>
								<td><code data-uix-part-marker>[{part.marker}]</code></td>
								<td class="type">&lt;{part.defaultElement}&gt;</td>
								<td class="type">{part.role ?? '—'}</td>
								<td class="default">{part.archetype ?? '—'}</td>
								<td class="default">{part.states.length ? part.states.join(' | ') : '—'}</td>
								<td class="default">{part.optional ? 'yes' : 'no'}</td>
							</tr>
						{/each}
					</tbody>
				</table>
			</div>

			<div data-uix-subsection-head>Events declaration</div>
			<div data-uix-table-wrap>
				<table data-uix-table>
					<thead><tr><th>name</th><th>family</th><th>verb</th><th>sequence</th><th>intent</th><th>target</th></tr></thead>
					<tbody>
						{#each events as action (action.name)}
							{@const sem = action.semantic}
							{@const intentDecl = 'intent' in sem ? sem.intent : undefined}
							{@const intentStr = typeof intentDecl === 'string' ? intentDecl : intentDecl ? `fromProp:${(intentDecl as { fromProp?: string }).fromProp ?? '?'}` : '—'}
							<tr>
								<td class="name">{action.name}</td>
								<td class="type">{sem.family}</td>
								<td>{sem.verb ?? '—'}</td>
								<td>{sem.sequence ?? 'pre'}</td>
								<td class="default">{intentStr}</td>
								<td>{action.target}</td>
							</tr>
						{/each}
					</tbody>
				</table>
			</div>
		</section>
	{/if}

	{#if tab === 'sema'}
		<section data-uix-section id="sema">
			<h2 data-uix-section-title>
				<span data-uix-layer-badge="sema">sema</span>
				· events
			</h2>
			<div data-uix-table-wrap>
				<table data-uix-table>
					<thead><tr><th>Name</th><th>Family</th><th>Verb</th><th>Sequence</th><th>Intent</th><th>Play</th></tr></thead>
					<tbody>
						{#each events as action (action.name)}
							{@const intentDecl = 'intent' in action.semantic ? action.semantic.intent : undefined}
							{@const effectiveIntent = typeof intentDecl === 'string' ? intentDecl : undefined}
							<tr>
								<td class="name">{action.name}</td>
								<td class="type">{action.semantic.family}</td>
								<td>{action.semantic.verb ?? '—'}</td>
								<td>{action.semantic.sequence ?? 'pre'}</td>
								<td class="default">{effectiveIntent ?? '—'}</td>
								<td>
									<button
										data-uix-play
										onclick={() => {
											const target = (stageRef?.querySelector('[data-feed-article]') ?? stageRef) as HTMLElement | null;
											if (!target) return;
											void uix.events?.emit({
												name: action.name,
												family: action.semantic.family,
												target,
												...(effectiveIntent ? { intent: effectiveIntent } : {})
											});
										}}
									>▶ play</button>
								</td>
							</tr>
						{/each}
					</tbody>
				</table>
			</div>
		</section>
	{/if}

	{#if tab === 'recipe'}
		<section data-uix-section>
			<h2 data-uix-section-title>Eidos recipe</h2>
			<p data-uix-section-desc>Selectors at <code>src/uix/eidos/components/feed/feed.css</code>.</p>
			<div data-uix-table-wrap>
				<table data-uix-table>
					<thead><tr><th>Selector</th><th>Source</th><th>What it paints</th></tr></thead>
					<tbody>
						<tr><td class="name">[data-feed-root]</td><td><span data-uix-tag data-kind="eidos">eidos</span></td><td>Wrapper — chrome, scroll region.</td></tr>
						<tr><td class="name">[data-feed-root][data-variant] [data-feed-article]</td><td><span data-uix-tag data-kind="eidos">eidos</span></td><td>Article card chrome per variant.</td></tr>
						<tr><td class="name">[data-feed-article-title][aria-level]</td><td><span data-uix-tag data-kind="soma">morfo</span></td><td>Font-size scaled by heading level.</td></tr>
						<tr><td class="name">[data-feed-thread]</td><td><span data-uix-tag data-kind="eidos">eidos</span></td><td>Nested feed with accent border indent.</td></tr>
						<tr><td class="name">[data-feed][data-busy] [data-feed-sentinel]::before</td><td><span data-uix-tag data-kind="eidos">eidos</span></td><td>Spinner during load.</td></tr>
					</tbody>
				</table>
			</div>
		</section>
	{/if}

	{#if tab === 'a11y'}
		<section data-uix-section>
			<h2 data-uix-section-title>Accessibility</h2>
			<p data-uix-section-desc>Follows the APG <a href={feedMorfo.apg} target="_blank" rel="noreferrer">feed pattern</a>. Root is <code>role="feed"</code>, each child is <code>role="article"</code> with <code>aria-posinset</code> / <code>aria-setsize</code> auto-wired. <code>aria-setsize="-1"</code> when total is unknown (per APG).</p>

			<div data-uix-subsection-head>Keyboard</div>
			<div data-uix-table-wrap>
				<table data-uix-table>
					<thead><tr><th>Key</th><th>Action</th></tr></thead>
					<tbody>
						<tr><td><span data-uix-kbd>PageDown</span> (on Article)</td><td>Focus next article. At the last one, calls <code>onLoadMore</code>.</td></tr>
						<tr><td><span data-uix-kbd>PageUp</span> (on Article)</td><td>Focus previous article.</td></tr>
						<tr><td><span data-uix-kbd>Ctrl+Home</span> / <span data-uix-kbd>Ctrl+End</span></td><td>First / last article.</td></tr>
						<tr><td><span data-uix-kbd>Tab</span> (within Article)</td><td>Reach inner interactive elements per native tab order.</td></tr>
					</tbody>
				</table>
			</div>
		</section>
	{/if}
</div>