Fullfører oppgave 16.3: MixerTrait-komponent med kanalstriper

Implementerer Mixer-UI som trait-komponent for samlingssider:
- Kanalstripe per deltaker med volumslider (0–150%), VU-meter (CSS),
  nød-mute-knapp (rød, tydelig) og navnelabel
- Master-seksjon med fader, VU-meter og master-mute
- Responsivt design: stacked layout på mobil, horisontal på desktop
- Animert VU-meter via requestAnimationFrame og AnalyserNode-data
- Integrert i collection-siden som 'mixer'-trait

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/lib/components/traits/MixerTrait.svelte

@@ -0,0 +1,291 @@
+<script lang="ts">
+	import type { Node } from '$lib/spacetime';
+	import TraitPanel from './TraitPanel.svelte';
+	import {
+		getStatus,
+		getParticipants,
+		getLocalIdentity,
+		subscribe,
+		type LiveKitParticipant,
+	} from '$lib/livekit';
+	import {
+		getChannelLevels,
+		getMasterLevels,
+		setChannelGain,
+		getChannelGain,
+		muteChannel,
+		unmuteChannel,
+		setMasterGain,
+		getMasterGain,
+		muteMaster,
+		unmuteMaster,
+		getChannelIdentities,
+		type ChannelLevels,
+	} from '$lib/mixer';
+
+	interface Props {
+		collection: Node;
+		config: Record<string, unknown>;
+		accessToken?: string;
+	}
+
+	let { collection, config, accessToken }: Props = $props();
+
+	// LiveKit state
+	let participants: LiveKitParticipant[] = $state([]);
+	let localIdentity: string = $state('');
+	let isConnected = $derived(getStatus() === 'connected');
+
+	// Per-channel UI state: tracks gain values and mute state for UI
+	let channelStates: Map<string, { gain: number; muted: boolean }> = $state(new Map());
+	let masterState = $state({ gain: 1.0, muted: false });
+
+	// VU meter levels (updated via animation frame)
+	let channelLevels: Map<string, ChannelLevels> = $state(new Map());
+	let masterLevels: ChannelLevels | null = $state(null);
+
+	// Animation frame for VU meters
+	let animFrameId: number | null = null;
+
+	$effect(() => {
+		const unsub = subscribe(() => {
+			participants = getParticipants();
+			localIdentity = getLocalIdentity();
+
+			// Sync channel states for new participants
+			const activeIdentities = getChannelIdentities();
+			for (const id of activeIdentities) {
+				if (!channelStates.has(id)) {
+					channelStates.set(id, { gain: getChannelGain(id), muted: false });
+					channelStates = new Map(channelStates);
+				}
+			}
+		});
+		return unsub;
+	});
+
+	// Start/stop VU meter animation loop based on connection
+	$effect(() => {
+		if (getStatus() === 'connected') {
+			startVuLoop();
+		} else {
+			stopVuLoop();
+		}
+		return () => stopVuLoop();
+	});
+
+	function startVuLoop() {
+		if (animFrameId !== null) return;
+		function tick() {
+			// Read levels for all channels
+			const newLevels = new Map<string, ChannelLevels>();
+			for (const id of getChannelIdentities()) {
+				const l = getChannelLevels(id);
+				if (l) newLevels.set(id, l);
+			}
+			channelLevels = newLevels;
+			masterLevels = getMasterLevels();
+			animFrameId = requestAnimationFrame(tick);
+		}
+		animFrameId = requestAnimationFrame(tick);
+	}
+
+	function stopVuLoop() {
+		if (animFrameId !== null) {
+			cancelAnimationFrame(animFrameId);
+			animFrameId = null;
+		}
+	}
+
+	// Channel controls
+	function handleGainChange(identity: string, value: number) {
+		setChannelGain(identity, value);
+		const state = channelStates.get(identity);
+		if (state) {
+			state.gain = value;
+			state.muted = false;
+			channelStates = new Map(channelStates);
+		}
+	}
+
+	function handleEmergencyMute(identity: string) {
+		const state = channelStates.get(identity);
+		if (!state) return;
+
+		if (state.muted) {
+			unmuteChannel(identity, state.gain);
+			state.muted = false;
+		} else {
+			muteChannel(identity);
+			state.muted = true;
+		}
+		channelStates = new Map(channelStates);
+	}
+
+	// Master controls
+	function handleMasterGainChange(value: number) {
+		setMasterGain(value);
+		masterState.gain = value;
+		masterState.muted = false;
+	}
+
+	function handleMasterMute() {
+		if (masterState.muted) {
+			unmuteMaster(masterState.gain);
+			masterState.muted = false;
+		} else {
+			muteMaster();
+			masterState.muted = true;
+		}
+	}
+
+	// VU meter helpers
+	function vuPercent(levels: ChannelLevels | null | undefined): number {
+		if (!levels) return 0;
+		return Math.min(100, levels.rms * 100 * 3); // scale up for visibility
+	}
+
+	function vuColor(levels: ChannelLevels | null | undefined): string {
+		if (!levels) return 'bg-gray-300';
+		const peak = levels.peak;
+		if (peak > 0.9) return 'bg-red-500';
+		if (peak > 0.6) return 'bg-yellow-400';
+		return 'bg-green-500';
+	}
+
+	function displayName(identity: string): string {
+		const p = participants.find(p => p.identity === identity);
+		if (!p) return identity;
+		if (p.identity === localIdentity) return `${p.displayName} (deg)`;
+		return p.displayName;
+	}
+
+	function gainToPercent(gain: number): number {
+		return Math.round(gain * 100);
+	}
+
+	// Channels that have actual audio (from mixer.ts)
+	const activeChannels = $derived(getChannelIdentities());
+	// Show participants that are in the room, with mixer channels where available
+	const displayChannels = $derived.by(() => {
+		const identities = new Set<string>();
+		for (const id of activeChannels) identities.add(id);
+		for (const p of participants) {
+			if (p.identity !== localIdentity) identities.add(p.identity);
+		}
+		return Array.from(identities);
+	});
+</script>
+
+<TraitPanel name="mixer" label="Mixer" icon="🎚️">
+	{#snippet children()}
+		{#if getStatus() !== 'connected'}
+			<p class="text-sm text-gray-400">Koble til opptak-rommet for å bruke mixeren.</p>
+		{:else if displayChannels.length === 0}
+			<p class="text-sm text-gray-400">Ingen lydkanaler aktive.</p>
+		{:else}
+			<!-- Channel strips -->
+			<div class="space-y-2 sm:space-y-3">
+				{#each displayChannels as identity (identity)}
+					{@const state = channelStates.get(identity)}
+					{@const levels = channelLevels.get(identity)}
+					{@const isMuted = state?.muted ?? false}
+					{@const gain = state?.gain ?? 1.0}
+
+					<div class="rounded-lg border border-gray-100 bg-gray-50 p-2 sm:p-3">
+						<!-- Mobile: stacked / Desktop: horizontal -->
+						<div class="flex flex-col gap-2 sm:flex-row sm:items-center sm:gap-3">
+							<!-- Name label -->
+							<span class="text-xs font-medium text-gray-700 truncate sm:w-28 sm:flex-shrink-0">
+								{displayName(identity)}
+							</span>
+
+							<!-- VU meter -->
+							<div class="h-2 flex-shrink-0 rounded-full bg-gray-200 overflow-hidden sm:w-20 sm:flex-shrink-0">
+								<div
+									class="h-full rounded-full transition-none {isMuted ? 'bg-gray-300' : vuColor(levels)}"
+									style="width: {isMuted ? 0 : vuPercent(levels)}%"
+								></div>
+							</div>
+
+							<!-- Volume slider -->
+							<div class="flex items-center gap-2 flex-1 min-w-0">
+								<input
+									type="range"
+									min="0"
+									max="1.5"
+									step="0.01"
+									value={gain}
+									oninput={(e) => handleGainChange(identity, parseFloat((e.target as HTMLInputElement).value))}
+									disabled={isMuted}
+									class="flex-1 h-2 accent-indigo-600 disabled:opacity-40"
+								/>
+								<span class="text-xs text-gray-500 w-10 text-right tabular-nums flex-shrink-0">
+									{gainToPercent(gain)}%
+								</span>
+							</div>
+
+							<!-- Emergency mute button -->
+							<button
+								onclick={() => handleEmergencyMute(identity)}
+								class="flex-shrink-0 rounded-lg px-3 py-2 text-xs font-bold uppercase tracking-wide transition-colors
+									{isMuted
+										? 'bg-red-600 text-white shadow-md hover:bg-red-700'
+										: 'bg-red-100 text-red-700 hover:bg-red-200'}"
+								title={isMuted ? 'Slå på lyd' : 'Nøddemp'}
+							>
+								{isMuted ? 'DEMPET' : 'DEMP'}
+							</button>
+						</div>
+					</div>
+				{/each}
+			</div>
+
+			<!-- Master section -->
+			<div class="mt-4 rounded-lg border-2 border-gray-200 bg-white p-3">
+				<div class="flex flex-col gap-2 sm:flex-row sm:items-center sm:gap-3">
+					<span class="text-xs font-bold text-gray-800 uppercase tracking-wide sm:w-28 sm:flex-shrink-0">
+						Master
+					</span>
+
+					<!-- Master VU meter -->
+					<div class="h-2.5 flex-shrink-0 rounded-full bg-gray-200 overflow-hidden sm:w-20 sm:flex-shrink-0">
+						<div
+							class="h-full rounded-full transition-none {masterState.muted ? 'bg-gray-300' : vuColor(masterLevels)}"
+							style="width: {masterState.muted ? 0 : vuPercent(masterLevels)}%"
+						></div>
+					</div>
+
+					<!-- Master slider -->
+					<div class="flex items-center gap-2 flex-1 min-w-0">
+						<input
+							type="range"
+							min="0"
+							max="1.5"
+							step="0.01"
+							value={masterState.gain}
+							oninput={(e) => handleMasterGainChange(parseFloat((e.target as HTMLInputElement).value))}
+							disabled={masterState.muted}
+							class="flex-1 h-2 accent-indigo-600 disabled:opacity-40"
+						/>
+						<span class="text-xs text-gray-500 w-10 text-right tabular-nums flex-shrink-0">
+							{gainToPercent(masterState.gain)}%
+						</span>
+					</div>
+
+					<!-- Master mute -->
+					<button
+						onclick={handleMasterMute}
+						class="flex-shrink-0 rounded-lg px-4 py-2.5 text-sm font-bold uppercase tracking-wide transition-colors
+							{masterState.muted
+								? 'bg-red-600 text-white shadow-lg hover:bg-red-700 ring-2 ring-red-300'
+								: 'bg-red-100 text-red-700 hover:bg-red-200'}"
+						title={masterState.muted ? 'Slå på master' : 'Demp alt'}
+					>
+						{masterState.muted ? 'DEMPET' : 'DEMP'}
+					</button>
+				</div>
+			</div>
+		{/if}
+	{/snippet}
+</TraitPanel>

frontend/src/routes/collection/[id]/+page.svelte

@@ -14,6 +14,7 @@
 	import RecordingTrait from '$lib/components/traits/RecordingTrait.svelte';
 	import TranscriptionTrait from '$lib/components/traits/TranscriptionTrait.svelte';
 	import StudioTrait from '$lib/components/traits/StudioTrait.svelte';
+	import MixerTrait from '$lib/components/traits/MixerTrait.svelte';
 	import GenericTrait from '$lib/components/traits/GenericTrait.svelte';
 	import TraitAdmin from '$lib/components/traits/TraitAdmin.svelte';
 	import NodeUsage from '$lib/components/NodeUsage.svelte';
@@ -49,7 +50,7 @@
 	/** Traits with dedicated components */
 	const knownTraits = new Set([
 		'editor', 'chat', 'kanban', 'podcast', 'publishing',
-		'rss', 'calendar', 'recording', 'transcription', 'studio'
+		'rss', 'calendar', 'recording', 'transcription', 'studio', 'mixer'
 	]);
 
 	/** Traits that have a dedicated component */
@@ -169,6 +170,8 @@
 						<TranscriptionTrait collection={collectionNode} config={traits[trait]} />
 					{:else if trait === 'studio'}
 						<StudioTrait collection={collectionNode} config={traits[trait]} userId={nodeId} />
+					{:else if trait === 'mixer'}
+						<MixerTrait collection={collectionNode} config={traits[trait]} {accessToken} />
 					{/if}
 				{/each}
 

tasks.md

@@ -179,8 +179,7 @@ Ref: `docs/features/lydmixer.md`
 
 - [x] 16.1 LiveKit-klient i frontend: installer `livekit-client`, koble til rom, vis deltakerliste. Deaktiver LiveKit sin auto-attach av `<audio>`-elementer — lyd rutes gjennom Web Audio API i stedet.
 - [x] 16.2 Web Audio mixer-graf: opprett `AudioContext`, `MediaStreamSourceNode` per remote track → per-kanal `GainNode` → master `GainNode` → `destination`. `AnalyserNode` per kanal for VU-meter.
-- [~] 16.3 Mixer-UI (MixerTrait-komponent): kanalstripe per deltaker med volumslider (0–150%), nød-mute-knapp (stor, rød), VU-meter (canvas/CSS), navnelabel. Master-fader og master-mute. Responsivt design (mobil: kompakt fader-modus).
+- [x] 16.3 Mixer-UI (MixerTrait-komponent): kanalstripe per deltaker med volumslider (0–150%), nød-mute-knapp (stor, rød), VU-meter (canvas/CSS), navnelabel. Master-fader og master-mute. Responsivt design (mobil: kompakt fader-modus).
-  > Påbegynt: 2026-03-18T04:54
 - [ ] 16.4 Delt mixer-kontroll via SpacetimeDB: `MixerChannel`-tabell + reducers (`set_gain`, `set_mute`, `toggle_effect`). Frontend abonnerer og oppdaterer Web Audio-graf ved endring fra andre deltakere. Visuell feedback (sliders beveger seg i sanntid). Tilgangskontroll: eier/admin kan sette deltaker til viewer-modus.
 - [ ] 16.5 Sound pads: pad-grid UI (4×2), forhåndslast lydfiler fra CAS til `AudioBuffer`. Avspilling ved trykk (`AudioBufferSourceNode`). Pad-konfig i `metadata.mixer.pads` (label, farge, cas_hash). Synkronisert avspilling via LiveKit Data Message.
 - [ ] 16.6 EQ-effektkjede: fat bottom (`BiquadFilterNode` lowshelf ~200Hz), sparkle (`BiquadFilterNode` highshelf ~10kHz), exciter (`WaveShaperNode` + highshelf). Per-kanal toggles, synkronisert via STDB. Presets (podcast-stemme, radio-stemme).