Add a button to spotlight a video feed

src/app/components/VideoCallContent.svelte

@@ -2,6 +2,9 @@
   import cx from "classnames"
   import {Track} from "livekit-client"
   import {displayProfileByPubkey, loadProfile} from "@welshman/app"
+  import Pin from "@assets/icons/pin.svg?dataurl"
+  import Button from "@lib/components/Button.svelte"
+  import Icon from "@lib/components/Icon.svelte"
   import ProfileCircle from "@app/components/ProfileCircle.svelte"
   import VideoCallVideo from "@app/components/VideoCallVideo.svelte"
   import {
@@ -9,6 +12,8 @@
     currentVoiceRoom,
     videoCallContentActive,
     videoCallLayoutRevision,
+    videoPrimaryTileKey,
+    toggleVideoPrimaryTile,
     pubkeyFromLiveKitIdentity,
   } from "@app/voice"
 
@@ -30,6 +35,8 @@
     source: Track.Source.Camera | Track.Source.ScreenShare
   }
 
+  type TileLayout = "spotlight" | "default" | "strip"
+
   const {variant, url, h, visible = true, class: className = ""}: Props = $props()
 
   const roomMatches = $derived($currentVoiceRoom?.url === url && $currentVoiceRoom?.h === h)
@@ -102,6 +109,33 @@
     return out
   })
 
+  /** Identity + source only — LiveKit can change trackSid after publish, which broke spotlight + stale-key effect. */
+  const tileKey = (t: Tile) => `${t.identity}\x1f${t.source}`
+
+  const primaryTile = $derived.by(() => {
+    const k = $videoPrimaryTileKey
+    if (k === undefined) return undefined
+    return tiles.find(t => tileKey(t) === k)
+  })
+
+  const secondaryTiles = $derived.by(() => {
+    const p = primaryTile
+    if (p === undefined) return tiles
+    const pk = tileKey(p)
+    return tiles.filter(t => tileKey(t) !== pk)
+  })
+
+  const useSpotlightLayout = $derived(primaryTile !== undefined)
+  const useMultiGrid = $derived(!useSpotlightLayout && tiles.length > 2)
+
+  $effect(() => {
+    const k = $videoPrimaryTileKey
+    if (k === undefined) return
+    if (!tiles.some(t => tileKey(t) === k)) {
+      videoPrimaryTileKey.set(undefined)
+    }
+  })
+
   $effect(() => {
     for (const t of tiles) {
       const pk = pubkeyFromLiveKitIdentity(t.identity)
@@ -116,43 +150,90 @@
   }
 
   const showTileGrid = $derived(tiles.length > 0)
+
+  const spotlightHandlerFor = (key: string) => () => {
+    toggleVideoPrimaryTile(key)
+  }
+
+  const panelChrome = $derived(
+    cx(
+      variant === "mobile" &&
+        "cb ct cw z-compose bg-base-300/95 fixed inset-x-0 flex min-h-0 flex-col gap-2 overflow-hidden p-2 md:hidden",
+      variant === "desktop-split" &&
+        "cb ct cw-split-video z-compose bg-base-300/95 fixed hidden min-h-0 flex-col gap-2 overflow-hidden p-2 md:flex",
+      variant === "desktop-full" &&
+        "cb ct cw z-compose bg-base-300/95 fixed hidden min-h-0 flex-col gap-2 overflow-hidden p-2 md:flex",
+      className,
+    ),
+  )
 </script>
 
-{#if showPanel && (showTileGrid || allowEmptyPanel)}
+{#snippet videoTile(tile: Tile, layout: TileLayout)}
   <div
     class={cx(
-      variant === "mobile" &&
+      "relative isolate overflow-hidden rounded-box shadow-sm",
-        "cb ct cw z-compose bg-base-300/95 fixed inset-x-0 flex flex-col gap-2 overflow-y-auto p-2 md:hidden",
+      layout === "spotlight" && "min-h-0 flex-1",
-      variant === "desktop-split" &&
+      layout === "default" && "aspect-video w-full min-h-0",
-        "cb ct cw-split-video z-compose bg-base-300/95 fixed hidden flex-col gap-2 overflow-y-auto p-2 md:flex",
+      layout === "strip" && "aspect-video w-44 shrink-0",
-      variant === "desktop-full" &&
+      tile.source === Track.Source.ScreenShare ? "bg-black" : "bg-base-100",
-        "cb ct cw z-compose bg-base-300/95 fixed hidden flex-col gap-2 overflow-y-auto p-2 md:flex",
+      $videoPrimaryTileKey === tileKey(tile) &&
-      className,
+        "ring-2 ring-primary ring-offset-2 ring-offset-base-300",
     )}>
+    {#if tile.attachable}
+      <VideoCallVideo
+        track={tile.attachable}
+        muted={tile.isLocal}
+        fit={tile.source === Track.Source.ScreenShare ? "contain" : "cover"}
+        class="pointer-events-none absolute inset-0" />
+    {:else}
+      <div class="absolute inset-0 flex items-center justify-center">
+        <ProfileCircle pubkey={pubkeyFromLiveKitIdentity(tile.identity)} {url} size={14} />
+      </div>
+    {/if}
+    <span
+      class="pointer-events-none absolute bottom-1 left-1 max-w-[calc(100%-0.5rem)] truncate rounded bg-base-100/80 px-1.5 py-0.5 text-xs">
+      {labelFor(tile.identity, tile.source)}{tile.isLocal ? " (you)" : ""}
+    </span>
+    {#if tiles.length > 1}
+      <Button
+        data-tip={$videoPrimaryTileKey === tileKey(tile) ? "Exit spotlight" : "Spotlight"}
+        class="absolute right-1 top-1 z-20 btn btn-xs btn-circle btn-ghost bg-base-100/70"
+        onclick={spotlightHandlerFor(tileKey(tile))}>
+        <Icon icon={Pin} size={3} />
+      </Button>
+    {/if}
+  </div>
+{/snippet}
+
+{#if showPanel && (showTileGrid || allowEmptyPanel)}
+  <div class={panelChrome}>
     {#if showTileGrid}
-      {#each tiles as tile (tile.trackSid + tile.identity)}
+      {#if useSpotlightLayout && primaryTile}
-        <div
+        <div class="flex min-h-0 flex-1 flex-col gap-2 overflow-hidden">
-          class={cx(
+          {@render videoTile(primaryTile, "spotlight")}
-            "relative aspect-video overflow-hidden rounded-box shadow-sm",
+          {#if secondaryTiles.length > 0}
-            tile.source === Track.Source.ScreenShare ? "bg-black" : "bg-base-100",
+            <div
-          )}>
+              class="flex max-h-40 shrink-0 flex-row gap-2 overflow-x-auto overflow-y-hidden py-0.5">
-          {#if tile.attachable}
+              {#each secondaryTiles as tile (tileKey(tile))}
-            <VideoCallVideo
+                {@render videoTile(tile, "strip")}
-              track={tile.attachable}
+              {/each}
-              muted={tile.isLocal}
-              fit={tile.source === Track.Source.ScreenShare ? "contain" : "cover"}
-              class="absolute inset-0" />
-          {:else}
-            <div class="absolute inset-0 flex items-center justify-center">
-              <ProfileCircle pubkey={pubkeyFromLiveKitIdentity(tile.identity)} {url} size={14} />
             </div>
           {/if}
-          <span
-            class="absolute bottom-1 left-1 max-w-[calc(100%-0.5rem)] truncate rounded bg-base-100/80 px-1.5 py-0.5 text-xs">
-            {labelFor(tile.identity, tile.source)}{tile.isLocal ? " (you)" : ""}
-          </span>
         </div>
-      {/each}
+      {:else if useMultiGrid}
+        <div
+          class="grid min-h-0 flex-1 auto-rows-fr grid-cols-1 gap-2 overflow-y-auto sm:grid-cols-2">
+          {#each tiles as tile (tileKey(tile))}
+            {@render videoTile(tile, "default")}
+          {/each}
+        </div>
+      {:else}
+        <div class="flex min-h-0 flex-1 flex-col gap-2 overflow-y-auto">
+          {#each tiles as tile (tileKey(tile))}
+            {@render videoTile(tile, "default")}
+          {/each}
+        </div>
+      {/if}
     {:else}
       <div
         class="flex min-h-[12rem] flex-1 flex-col items-center justify-center gap-2 rounded-box bg-base-100/50 p-4 text-center text-sm opacity-80">

src/app/voice.ts

@@ -88,6 +88,13 @@ export const participantPubkeyMap = writable<Map<string, Pubkey>>(new Map())
 /** Bumps when remote video is subscribed/unsubscribed so layout/video UI can react. */
 export const videoCallLayoutRevision = writable(0)
 
+/** Spotlight tile id — must match VideoCallContent `tileKey` (identity + source, not trackSid). */
+export const videoPrimaryTileKey = writable<string | undefined>(undefined)
+
+export const toggleVideoPrimaryTile = (key: string) => {
+  videoPrimaryTileKey.update(k => (k === key ? undefined : key))
+}
+
 const bumpVideoCallLayoutRevision = () => videoCallLayoutRevision.update(n => n + 1)
 
 const addParticipant = (identity: string) => {
@@ -206,6 +213,7 @@ const setUpMicrophone = async (
 
 const onRoomDisconnected = (reason?: DisconnectReason) => {
   videoCallLayoutRevision.set(0)
+  videoPrimaryTileKey.set(undefined)
   currentVoiceSession.set(undefined)
   if (reason !== undefined && reason !== DisconnectReason.CLIENT_INITIATED) {
     voiceState.set(VoiceState.Disconnected)
@@ -372,6 +380,7 @@ export const leaveVoiceRoom = async () => {
 
   voiceState.set(VoiceState.Disconnected)
   videoCallLayoutRevision.set(0)
+  videoPrimaryTileKey.set(undefined)
   currentVoiceSession.set(undefined)
   session.room.disconnect()
   speakingParticipants.set([])