music: styled hover/focus/tap tooltip with exact hours and date on the hours-per-day chart

src/routes/trackers/music/+page.svelte

@@ -25,6 +25,41 @@
 		local: 'local files'
 	};
 	const now = Date.now();
+
+	// Hours-per-day chart: a styled tooltip on hover, keyboard focus or tap (roving tabindex,
+	// arrow keys move between days, Escape closes).
+	let activeDay = $state<number | null>(null);
+	let focusDay = $state<number | null>(null);
+	let bars = $state<HTMLButtonElement[]>([]);
+	const tabDay = $derived(focusDay ?? s.daily.length - 1);
+	const tipDay = $derived(activeDay === null ? null : s.daily[activeDay]);
+	const fullDayLabel = (day: string) =>
+		new Date(`${day}T12:00:00Z`).toLocaleDateString('en-GB', {
+			weekday: 'short',
+			day: 'numeric',
+			month: 'short',
+			year: 'numeric'
+		});
+	const exactHours = (h: number) =>
+		`${h.toLocaleString('en-GB', { minimumFractionDigits: 1, maximumFractionDigits: 1 })} h`;
+	const tipShift = (pos: number) => (pos < 0.15 ? '-10%' : pos > 0.85 ? '-90%' : '-50%');
+	function moveDay(event: KeyboardEvent, i: number) {
+		if (event.key === 'Escape') {
+			activeDay = null;
+			return;
+		}
+		const last = s.daily.length - 1;
+		const next: Record<string, number> = {
+			ArrowLeft: Math.max(0, i - 1),
+			ArrowRight: Math.min(last, i + 1),
+			Home: 0,
+			End: last
+		};
+		if (!(event.key in next)) return;
+		event.preventDefault();
+		focusDay = next[event.key];
+		bars[focusDay]?.focus();
+	}
 </script>
 
 <div class="mx-auto max-w-6xl px-4 py-12 sm:px-6 sm:py-16">
@@ -124,15 +159,62 @@
 				>(last {s.daily.length} days)</span
 			>
 		</h2>
-		<div class="flex h-32 items-end gap-px rounded-md border border-[var(--site-border)] p-2">
-			{#each s.daily as d (d.day)}
+		<div class="relative">
 			<div
-					class="flex-1 rounded-sm bg-[#1db954]/80"
+				class="flex h-32 items-end gap-px rounded-md border border-[var(--site-border)] p-2"
+				role="group"
+				aria-label="hours listened per day"
+				onpointerleave={(e) => {
+					if (e.pointerType === 'mouse') activeDay = null;
+				}}
+			>
+				{#each s.daily as d, i (d.day)}
+					<button
+						type="button"
+						bind:this={bars[i]}
+						class="group flex h-full min-w-0 flex-1 cursor-default items-end rounded-sm focus-visible:outline-2 focus-visible:outline-offset-1 focus-visible:outline-[var(--site-text)]"
+						tabindex={i === tabDay ? 0 : -1}
+						aria-label="{fullDayLabel(d.day)}: {exactHours(d.hours)}, {d.plays} plays"
+						onpointerenter={(e) => {
+							if (e.pointerType === 'mouse') activeDay = i;
+						}}
+						onclick={(e) => {
+							const mouse = (e as PointerEvent).pointerType === 'mouse';
+							activeDay = !mouse && activeDay === i ? null : i;
+						}}
+						onfocus={() => {
+							focusDay = i;
+							activeDay = i;
+						}}
+						onblur={() => {
+							if (activeDay === i) activeDay = null;
+						}}
+						onkeydown={(e) => moveDay(e, i)}
+					>
+						<span
+							class="block w-full rounded-sm transition-colors {activeDay === i
+								? 'bg-[#1db954]'
+								: 'bg-[#1db954]/80 group-hover:bg-[#1db954]'}"
 							style="height: {Math.max(d.hours > 0 ? 3 : 0, (d.hours / maxHours) * 100)}%"
-					title="{dayLabel(d.day)}: {fmtHours(d.hours)} h, {d.plays} plays"
-				></div>
+						></span>
+					</button>
 				{/each}
 			</div>
+			{#if tipDay && activeDay !== null}
+				{@const pos = (activeDay + 0.5) / s.daily.length}
+				<div
+					class="pointer-events-none absolute bottom-full z-10 mb-2 rounded-md border border-[var(--site-border)] bg-[var(--site-surface)] px-3 py-1.5 text-sm whitespace-nowrap shadow-lg"
+					style="left: calc(0.5rem + {pos} * (100% - 1rem)); transform: translateX({tipShift(pos)})"
+					aria-hidden="true"
+				>
+					<span class="block font-semibold tabular-nums">{exactHours(tipDay.hours)}</span>
+					<span class="block text-xs text-[var(--site-muted)]"
+						>{fullDayLabel(tipDay.day)} · {tipDay.plays.toLocaleString('en-GB')}
+						{tipDay.plays === 1 ? 'play' : 'plays'}</span
+					>
+				</div>
+			{/if}
+		</div>
 		<div class="mt-1 flex justify-between text-xs text-[var(--site-muted)]">
 			<span>{dayLabel(s.daily[0]?.day ?? '')}</span><span>today</span>
 		</div>