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

<script lang="ts">
	import {
		DragDrop,
		type DragDropSize,
		type DragDropColor,
		type DropEvent
	} from '$uix/eidos/components/drag-drop';
	import { compileMorfo } from '$uix/morfo';
	import { dragDropMorfo } from '@/uix/morfo/components/drag-drop';
	import { getActiveUix } from '$active-uix';

	const uix = getActiveUix();

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

	type Item = { id: string; label: string };
	let columns = $state<Record<string, Item[]>>({
		todo: [
			{ id: 't1', label: 'Write specs' },
			{ id: 't2', label: 'Review PR #42' },
			{ id: 't3', label: 'Sync with design' }
		],
		doing: [{ id: 'd1', label: 'Ship TreeGrid' }],
		done: [
			{ id: 'x1', label: 'Refactor Table' },
			{ id: 'x2', label: 'Carousel autoplay' }
		]
	});

	let size = $state<DragDropSize>('md');
	let color = $state<DragDropColor>('primary');
	let announceEnabled = $state(true);
	let moveBuffer = $state(5);

	function handleDrop(e: DropEvent<{ from: string }>) {
		const fromColumn = e.data.from;
		const toColumn = e.target.dataset.column!;
		if (fromColumn === toColumn) return;
		const item = columns[fromColumn].find((i) => i.id === e.value);
		if (!item) return;
		columns = {
			...columns,
			[fromColumn]: columns[fromColumn].filter((i) => i.id !== e.value),
			[toColumn]: [...columns[toColumn], item]
		};
	}

	const COL_LABELS: Record<string, string> = {
		todo: 'Todo',
		doing: 'In progress',
		done: 'Done'
	};

	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();
	});

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

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

	const totalItems = $derived(
		Object.values(columns).reduce((sum, list) => sum + list.length, 0)
	);

	const eidosSnippet = $derived(
		[
			"<script lang='ts'>",
			"  import { DragDrop } from '$uix/eidos/components/drag-drop';",
			'</' + 'script>',
			'',
			'<DragDrop',
			'  onDrop={handleDrop}',
			!announceEnabled && '  announceEnabled={false}',
			size !== 'md' && `  size="${size}"`,
			color !== 'primary' && `  color="${color}"`,
			'>',
			'  {#snippet children({ active })}',
			'    <DragDrop.Droppable accept={(d) => d.kind === "task"}>',
			'      {#snippet children({ over, accepting })}',
			'        <div data-column="todo">…</div>',
			'      {/snippet}',
			'    </DragDrop.Droppable>',
			'    <DragDrop.Draggable',
			'      value="t1"',
			'      data={{ kind: "task", from: "todo" }}',
			moveBuffer !== 5 && `      moveBuffer={${moveBuffer}}`,
			'    >',
			'      <div>Card</div>',
			'    </DragDrop.Draggable>',
			'    {#if active}',
			'      <DragDrop.Preview>{active.label}</DragDrop.Preview>',
			'    {/if}',
			'  {/snippet}',
			'</DragDrop>'
		]
			.filter(Boolean)
			.join('\n')
	);
</script>

<div data-uix-canvas-inner>
	<header>
		<div data-uix-eyebrow>Utility · DragDrop</div>
		<h1 data-uix-page-title>DragDrop</h1>
		<p data-uix-page-lede>
			Pointer + keyboard drag and drop. Soma owns the gesture coordinator and
			ARIA announcements via the global <code>Announce</code> service. Eidos
			paints the visual states (<code>data-dragging</code> ghosts the source,
			<code>data-accepting</code> highlights compatible targets,
			<code>data-dragover</code> tints the hover target with the accent color).
		</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>cards</span> {totalItems}
			</span>
			<span data-uix-meta-pill>
				<span data-uix-meta-key>columns</span> {Object.keys(columns).length}
			</span>
		</div>
	</header>

	<DragDrop
		{size}
		{color}
		{announceEnabled}
		onDrop={(e) => handleDrop(e as DropEvent<{ from: string }>)}
	>
		{#snippet children(snippetProps)}
			{@const { active } = snippetProps}
			<div data-uix-stage>
				<div data-uix-stage-area bind:this={stageRef} style="padding: var(--uix-space-3); display: flex; gap: var(--uix-space-3); flex-wrap: wrap; align-items: flex-start;">
					{#each Object.keys(columns) as colKey (colKey)}
						<DragDrop.Droppable
							textValue={COL_LABELS[colKey]}
							data-column={colKey}
							style="inline-size: 12rem; min-block-size: 14rem; padding: var(--uix-space-2); border: 1px dashed var(--color-border-default); border-radius: var(--radius-md); background: var(--color-surface-subtle); display: block;"
						>
							{#snippet children(_dropSnippet)}
								<div style="font-weight: var(--font-weight-semibold, 600); margin-block-end: 0.5rem;">
									{COL_LABELS[colKey]}
									<span style="color: var(--color-content-secondary); font-weight: normal; font-size: var(--font-size-xs);">· {columns[colKey].length}</span>
								</div>
								<div style="display: flex; flex-direction: column; gap: var(--uix-space-1);">
									{#each columns[colKey] as item (item.id)}
										<DragDrop.Draggable value={item.id} data={{ from: colKey }} textValue={item.label} {moveBuffer}>
											<div style="padding: var(--uix-space-2) var(--uix-space-3); border-radius: var(--radius-sm); background: var(--color-surface-default); border: 1px solid var(--color-border-default); font-size: var(--font-size-sm);">
												⋮⋮ {item.label}
											</div>
										</DragDrop.Draggable>
									{/each}
								</div>
							{/snippet}
						</DragDrop.Droppable>
					{/each}
				</div>
				<div data-uix-stage-trace>
					<span data-uix-stage-trace-key>trace</span>
					{#if active}
						<span><strong>{active.label}</strong> · from {(active.data as { from?: string }).from}</span>
					{:else if trace.length === 0}
						<span>drag cards across columns · keyboard: Tab → Space → arrows → Enter / Escape</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}
				</div>
			</div>

			{#if active}
				<DragDrop.Preview>⋮⋮ {active.label}</DragDrop.Preview>
			{/if}
		{/snippet}
	</DragDrop>

	<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>4</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 coordinates the gesture (pointer + keyboard), filters drop targets by <code>accept</code>, and announces via the global Announce service. Eidos paints the visual states.
			</p>

			<div data-uix-subsection-head>
				<span data-uix-layer-badge="soma">soma</span> behaviour
			</div>
			<div data-uix-controls>
				<label data-uix-control>
					<span data-uix-control-label>moveBuffer</span>
					<span data-uix-chips role="radiogroup">
						{#each [0, 5, 12, 24] as n (n)}
							<button data-uix-chip data-active={moveBuffer === n} onclick={() => (moveBuffer = n)}>{n}px</button>
						{/each}
					</span>
				</label>
				<label data-uix-control>
					<span data-uix-control-label>announceEnabled</span>
					<span data-uix-switch>
						<input type="checkbox" bind:checked={announceEnabled} />
						<span data-uix-switch-label>{announceEnabled ? 'SR announcements on' : 'silent'}</span>
					</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>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 DragDropSize)}>{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 DragDropColor)}>{c}</button>
						{/each}
					</span>
				</label>
			</div>

			<div data-uix-code>
				<div data-uix-code-head>
					<span data-uix-layer-badge="eidos">eidos</span>
					<span>visual · DragDrop + Draggable + Droppable + Preview</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>4 parts: <code>Provider · Draggable · Droppable · Preview</code>. The Provider does NOT own the data — consumer receives <code>onDrop</code> and mutates state.</p>

			<div data-uix-subsection-head>Provider (DragDrop)</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">onDragStart · onDragEnd · onDrop</td><td class="type">callbacks</td><td class="default empty">—</td><td>Gesture lifecycle hooks.</td></tr>
						<tr><td class="name">announceEnabled</td><td class="type">boolean</td><td class="default">true</td><td>Emit SR announcements via the global Announce service.</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>Cascaded visual size.</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>Accent for drop targets + preview border + shadow.</td></tr>
					</tbody>
				</table>
			</div>

			<div data-uix-subsection-head>Draggable</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">value</td><td class="type">string</td><td class="default empty">required</td><td>Unique identifier returned in onDrop.</td></tr>
						<tr><td class="name">data</td><td class="type">DragData</td><td class="default">{'{}'}</td><td>Arbitrary payload received in onDrop.</td></tr>
						<tr><td class="name">disabled</td><td class="type">boolean</td><td class="default">false</td><td>Skip from drag gesture.</td></tr>
						<tr><td class="name">moveBuffer</td><td class="type">number</td><td class="default">5</td><td>Pixels the pointer must move before drag is recognised.</td></tr>
						<tr><td class="name">textValue</td><td class="type">string</td><td class="default empty">aria-label/textContent</td><td>Label for SR announcements.</td></tr>
					</tbody>
				</table>
			</div>

			<div data-uix-subsection-head>Droppable</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">accept</td><td class="type">(data, value) => boolean</td><td class="default">() => true</td><td>Filter — return false to skip this target.</td></tr>
						<tr><td class="name">disabled</td><td class="type">boolean</td><td class="default">false</td><td>Disable drops.</td></tr>
						<tr><td class="name">textValue</td><td class="type">string</td><td class="default empty">—</td><td>Label for SR announcements.</td></tr>
					</tbody>
				</table>
			</div>

			<div data-uix-subsection-head>Snippet props</div>
			<div data-uix-table-wrap>
				<table data-uix-table>
					<thead><tr><th>Snippet</th><th>Key</th><th>Type</th><th>Description</th></tr></thead>
					<tbody>
						<tr><td class="name">Provider.children</td><td>active</td><td class="type">ActiveDrag | null</td><td>Info about the in-flight drag (value, data, label, pointer).</td></tr>
						<tr><td class="name">Provider.children</td><td>cancel</td><td class="type">() => void</td><td>Imperative cancel.</td></tr>
						<tr><td class="name">Draggable.children</td><td>dragging</td><td class="type">boolean</td><td>True while THIS draggable is the source.</td></tr>
						<tr><td class="name">Draggable.children</td><td>handleProps</td><td class="type">object</td><td>Spread on a child to restrict the drag handle.</td></tr>
						<tr><td class="name">Droppable.children</td><td>over</td><td class="type">boolean</td><td>Pointer/focus is over THIS target.</td></tr>
						<tr><td class="name">Droppable.children</td><td>accepting</td><td class="type">boolean</td><td>True for compatible targets while ANY drag is active.</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/drag-drop.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>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.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>
			{#if events.length === 0}
				<p data-uix-section-desc>DragDrop's SR feedback is delivered via the global Announce service rather than sema events — the perception is verbal, not audio cues.</p>
			{:else}
				<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></tr></thead>
						<tbody>
							{#each events as action (action.name)}
								{@const intentDecl = 'intent' in action.semantic ? action.semantic.intent : 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">{typeof intentDecl === 'string' ? intentDecl : '—'}</td>
								</tr>
							{/each}
						</tbody>
					</table>
				</div>
			{/if}
		</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/drag-drop/drag-drop.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-drag-drop-draggable]</td><td><span data-uix-tag data-kind="eidos">eidos</span></td><td><code>cursor: grab</code>, <code>touch-action: none</code>.</td></tr>
						<tr><td class="name">[data-drag-drop-draggable][data-dragging]</td><td><span data-uix-tag data-kind="soma">morfo</span></td><td>Source ghosted (<code>opacity: 0.4</code>).</td></tr>
						<tr><td class="name">[data-drag-drop-droppable][data-accepting]</td><td><span data-uix-tag data-kind="soma">morfo</span></td><td>Compatible target outline (soft accent).</td></tr>
						<tr><td class="name">[data-drag-drop-droppable][data-dragover]</td><td><span data-uix-tag data-kind="soma">morfo</span></td><td>Hover target accent fill + inset border.</td></tr>
						<tr><td class="name">[data-drag-drop-preview]</td><td><span data-uix-tag data-kind="eidos">eidos</span></td><td>Floating pointer follower — card chrome with accent border + shadow.</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>
				Full keyboard parity with pointer — and SR announcements via the global
				<code>Announce</code> service when <code>announceEnabled</code> is on.
			</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>Tab</span></td><td>Focus the next Draggable.</td></tr>
						<tr><td><span data-uix-kbd>Space</span></td><td>Lift the focused Draggable.</td></tr>
						<tr><td><span data-uix-kbd>Arrow</span> / <span data-uix-kbd>Tab</span></td><td>Navigate compatible Droppables.</td></tr>
						<tr><td><span data-uix-kbd>Enter</span></td><td>Drop on the current target.</td></tr>
						<tr><td><span data-uix-kbd>Escape</span></td><td>Cancel the lift.</td></tr>
					</tbody>
				</table>
			</div>

			<div data-uix-subsection-head>Announcements (via global Announce)</div>
			<ul style="margin: 0; padding-inline-start: 1.25rem; color: var(--color-content-secondary); font-size: var(--font-size-sm);">
				<li>Drag start → "Started dragging {`{item}`}"</li>
				<li>Drag over Droppable → "Over {`{target}`}"</li>
				<li>Drop → "Dropped {`{item}`} on {`{target}`}"</li>
				<li>Cancel → "Cancelled"</li>
			</ul>
		</section>
	{/if}
</div>