From 799a11b86d696d7ce9fcd9f1194c4dfda7a0a31e Mon Sep 17 00:00:00 2001
From: Iwwww <mike.yolgin@gmail.com>
Date: Mon, 29 Dec 2025 00:46:36 +0300
Subject: [PATCH] =?UTF-8?q?feat(frontend):=20=D0=B4=D0=BE=D0=B1=D0=B0?=
 =?UTF-8?q?=D0=B2=D0=BB=D0=B5=D0=BD=D1=8B=20=D0=B2=D0=B8=D0=B4=D0=B6=D0=B5?=
 =?UTF-8?q?=D1=82=D1=8B=20=D0=A2=D0=B5=D0=BA=D1=83=D1=89=D0=B0=D1=8F=20?=
 =?UTF-8?q?=D1=87=D0=B0=D1=81=D1=82=D0=BE=D1=82=D0=B0=20=D0=B8=20=D0=A4?=
 =?UTF-8?q?=D0=BE=D1=80=D0=BC=D0=B0=20=D0=B2=D0=BE=D0=BB=D0=BD=D1=8B?=
MIME-Version: 1.0
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Content-Transfer-Encoding: 8bit

---
 services/frontend/src/app/styles/index.css    |  12 ++
 .../liveStream/model/liveStream.store.ts      |   2 +-
 .../src/pages/dashboard/ui/DashboardPage.tsx  |   2 +-
 .../widgets/audioLive/ui/AudioLiveWidget.tsx  |  38 +++-
 .../src/widgets/audioLive/ui/AudioMeter.tsx   |   8 +-
 .../audioLive/ui/FrequencyCurrentDisplay.tsx  | 188 ++++++++++++++++++
 .../audioLive/ui/FrequencyHistoryChart.tsx    |   6 +-
 .../widgets/audioLive/ui/WaveFormDisplay.tsx  | 131 ++++++++++++
 8 files changed, 367 insertions(+), 20 deletions(-)
 create mode 100644 services/frontend/src/widgets/audioLive/ui/FrequencyCurrentDisplay.tsx
 create mode 100644 services/frontend/src/widgets/audioLive/ui/WaveFormDisplay.tsx

diff --git a/services/frontend/src/app/styles/index.css b/services/frontend/src/app/styles/index.css
index 08ec482..5313301 100644
--- a/services/frontend/src/app/styles/index.css
+++ b/services/frontend/src/app/styles/index.css
@@ -123,3 +123,15 @@
     @apply bg-background text-foreground;
   }
 }
+
+@keyframes spin-slow {
+  from {
+    transform: rotate(0deg);
+  }
+  to {
+    transform: rotate(360deg);
+  }
+}
+.animate-spin-slow {
+  animation: spin-slow 4s linear infinite;
+}
diff --git a/services/frontend/src/features/liveStream/model/liveStream.store.ts b/services/frontend/src/features/liveStream/model/liveStream.store.ts
index 48e1285..122a455 100644
--- a/services/frontend/src/features/liveStream/model/liveStream.store.ts
+++ b/services/frontend/src/features/liveStream/model/liveStream.store.ts
@@ -167,7 +167,7 @@ export const useLiveStreamStore = create<LiveStreamState>()((set, get) => {
         peakWindow.push(sample);
         trimPeakWindow(sample.timeMs);
 
-        // Throttled UI update (important for Recharts + overall UI smoothness)
+        // Throttled UI update
         scheduleFlush();
       },
     });
diff --git a/services/frontend/src/pages/dashboard/ui/DashboardPage.tsx b/services/frontend/src/pages/dashboard/ui/DashboardPage.tsx
index 893aa97..3b6a7d0 100644
--- a/services/frontend/src/pages/dashboard/ui/DashboardPage.tsx
+++ b/services/frontend/src/pages/dashboard/ui/DashboardPage.tsx
@@ -7,7 +7,7 @@ export function DashboardPage() {
   return (
     <div className="mx-auto w-full max-w-6xl p-4 md:p-6">
       <header className="mb-4">
-        <h1 className="text-2xl font-semibold">STM32 Audio Analyze Dashboard</h1>
+        <h1 className="text-2xl font-semibold">STM32 Панель анализа звука</h1>
         <p className="text-sm text-muted-foreground">
           Частоты: 129 Гц - 5,5 кГц; Громкость: -50 - 0 дБ
         </p>
diff --git a/services/frontend/src/widgets/audioLive/ui/AudioLiveWidget.tsx b/services/frontend/src/widgets/audioLive/ui/AudioLiveWidget.tsx
index f97be16..6172f35 100644
--- a/services/frontend/src/widgets/audioLive/ui/AudioLiveWidget.tsx
+++ b/services/frontend/src/widgets/audioLive/ui/AudioLiveWidget.tsx
@@ -1,4 +1,3 @@
-// src/widgets/audioLive/ui/AudioLiveWidget.tsx
 import { useMemo } from "react";
 import { useLiveStreamStore } from "../../../features/liveStream/model/liveStream.store";
 import { WsStatusBadge } from "../../../features/liveStream/ui/WsStatusBadge";
@@ -12,6 +11,8 @@ import {
 } from "../../../shared/ui/card";
 import { freqToNote } from "../../../entities/audioSample/lib/note";
 import { formatTimeHHMMSS, isStale } from "../../../shared/lib/time";
+import { FrequencyCurrentDisplay } from "./FrequencyCurrentDisplay";
+import { WaveformDisplay } from "./WaveFormDisplay";
 
 const HZ_OPTIONS: number[] = [0.1, 0.25, 0.5, 1, 2.5, 5, 10, 15] as const;
 
@@ -23,6 +24,11 @@ const WINDOW_OPTIONS: Array<{ label: string; ms: number }> = [
   { label: "5m", ms: 300_000 },
 ];
 
+export const LOUDNESS_THRESHOLD = -35.0;
+
+export const MIN_FREQUENCY = 129;
+export const MAX_FREQUENCY = 5500;
+
 export function AudioLiveWidget() {
   const status = useLiveStreamStore((s) => s.status);
   const latest = useLiveStreamStore((s) => s.latest);
@@ -43,18 +49,18 @@ export function AudioLiveWidget() {
   }, [latest]);
 
   return (
-    <div className="grid gap-4 lg:grid-cols-3">
-      <div className="lg:col-span-1">
+    <div className="grid gap-4 lg:grid-cols-4">
+      <div className="lg:col-span-1 row-span-2">
         <AudioMeter
           rmsDb={latest?.rms_db ?? null}
           peakHoldDb3s={peakHoldDb3s}
         />
       </div>
 
-      <div className="lg:col-span-2 grid gap-4">
+      <div className="lg:col-span-3 row-span-3 grid gap-4">
         <Card>
           <CardHeader className="pb-2 flex flex-row items-center justify-between gap-3">
-            <CardTitle className="text-base">Live status</CardTitle>
+            <CardTitle className="text-base">Состояние</CardTitle>
             <div className="flex items-center gap-3">
               <WsStatusBadge status={status} />
             </div>
@@ -62,7 +68,7 @@ export function AudioLiveWidget() {
 
           <CardContent className="flex flex-wrap items-end justify-between gap-4">
             <div>
-              <div className="text-sm text-muted-foreground">Last update</div>
+              <div className="text-sm text-muted-foreground">Последнее обновление</div>
               <div className="text-lg font-medium tabular-nums">
                 {lastMessageAt ? formatTimeHHMMSS(lastMessageAt) : "—"}
                 <span
@@ -74,7 +80,7 @@ export function AudioLiveWidget() {
             </div>
 
             <div>
-              <div className="text-sm text-muted-foreground">Frequency</div>
+              <div className="text-sm text-muted-foreground">Частота</div>
               <div className="text-lg font-medium tabular-nums">
                 {latest ? `${latest.freq_hz.toFixed(0)} Hz` : "—"}{" "}
                 <span className="text-muted-foreground">({note})</span>
@@ -91,7 +97,7 @@ export function AudioLiveWidget() {
             {/* Controls */}
             <div className="flex flex-wrap items-end gap-3">
               <label className="grid gap-1">
-                <span className="text-sm text-muted-foreground">WS Hz</span>
+                <span className="text-sm text-muted-foreground">Частота обновлений</span>
                 <select
                   className="h-9 rounded-md border border-input bg-background px-3 text-sm"
                   value={requestedHz}
@@ -99,14 +105,14 @@ export function AudioLiveWidget() {
                 >
                   {HZ_OPTIONS.map((hz) => (
                     <option key={hz} value={hz}>
-                      {hz} Hz
+                      {hz} Гц
                     </option>
                   ))}
                 </select>
               </label>
 
               <label className="grid gap-1">
-                <span className="text-sm text-muted-foreground">Window</span>
+                <span className="text-sm text-muted-foreground">Окно</span>
                 <select
                   className="h-9 rounded-md border border-input bg-background px-3 text-sm"
                   value={windowMs}
@@ -122,9 +128,19 @@ export function AudioLiveWidget() {
             </div>
           </CardContent>
         </Card>
-
         <FrequencyHistoryChart history={chartHistory} />
       </div>
+
+      <div className="lg:col-span-1 row-span-2 grid gap-4">
+        <FrequencyCurrentDisplay
+          latest={latest}
+          history={chartHistory}
+          windowMs={windowMs}
+        />
+      </div>
+      <div className="lg:col-span-3 grid gap-4">
+        <WaveformDisplay latest={latest} />
+      </div>
     </div>
   );
 }
diff --git a/services/frontend/src/widgets/audioLive/ui/AudioMeter.tsx b/services/frontend/src/widgets/audioLive/ui/AudioMeter.tsx
index 705c22d..d1b874a 100644
--- a/services/frontend/src/widgets/audioLive/ui/AudioMeter.tsx
+++ b/services/frontend/src/widgets/audioLive/ui/AudioMeter.tsx
@@ -45,7 +45,7 @@ export function AudioMeter({ rmsDb, peakHoldDb3s }: Props) {
   return (
     <Card>
       <CardHeader className="pb-2">
-        <CardTitle className="text-base">Audio meter</CardTitle>
+        <CardTitle className="text-base">Аудио измеритель</CardTitle>
       </CardHeader>
 
       <CardContent className="flex items-center gap-4">
@@ -53,7 +53,7 @@ export function AudioMeter({ rmsDb, peakHoldDb3s }: Props) {
         <div className="flex items-stretch gap-3">
           {/* ticks */}
           <div className="flex flex-col justify-between text-xs text-muted-foreground h-56 select-none">
-            <div>0 dB</div>
+            <div>0 дБ</div>
             <div>-10</div>
             <div>-20</div>
             <div>-30</div>
@@ -78,13 +78,13 @@ export function AudioMeter({ rmsDb, peakHoldDb3s }: Props) {
 
         {/* Values */}
         <div className="min-w-40">
-          <div className="text-sm text-muted-foreground">Current</div>
+          <div className="text-sm text-muted-foreground">Сейчас</div>
           <div className="text-2xl font-semibold tabular-nums">
             {rmsDb === null ? "—" : `${rmsDb.toFixed(1)} dB`}
           </div>
 
           <div className="mt-3 text-sm text-muted-foreground">
-            Peak hold (3s)
+            Пик (3с)
           </div>
           <div className="text-lg font-medium tabular-nums">
             {peakHoldDb3s === null ? "—" : `${peakHoldDb3s.toFixed(1)} dB`}
diff --git a/services/frontend/src/widgets/audioLive/ui/FrequencyCurrentDisplay.tsx b/services/frontend/src/widgets/audioLive/ui/FrequencyCurrentDisplay.tsx
new file mode 100644
index 0000000..82ea5f2
--- /dev/null
+++ b/services/frontend/src/widgets/audioLive/ui/FrequencyCurrentDisplay.tsx
@@ -0,0 +1,188 @@
+import { memo, useMemo } from "react";
+import { Line, LineChart, ResponsiveContainer, Tooltip, XAxis } from "recharts";
+import {
+  Card,
+  CardContent,
+  CardHeader,
+  CardTitle,
+} from "../../../shared/ui/card";
+import type { AudioSample } from "../../../entities/audioSample/model/types";
+import { freqToNote } from "../../../entities/audioSample/lib/note";
+import { formatTimeHHMMSS } from "../../../shared/lib/time";
+import {
+  LOUDNESS_THRESHOLD,
+  MAX_FREQUENCY,
+  MIN_FREQUENCY,
+} from "./AudioLiveWidget";
+
+type Props = {
+  latest: AudioSample | null;
+  history: AudioSample[]; // последние ~15 секунд
+  windowMs: number;
+};
+
+const HISTORY_WINDOW_MS = 15_000; // 15 секунд истории
+const STABILITY_WINDOW = 5; // анализируем последние 10 точек
+
+function getStability(history: AudioSample[]): number {
+  if (history.length < STABILITY_WINDOW) return 1;
+  const recent = history.slice(-STABILITY_WINDOW);
+  const values = recent.map((s) => s.freq_hz);
+  // Среднее арифметическое
+  const mean = values.reduce((a, b) => a + b, 0) / values.length;
+  // Дисперсия
+  const variance =
+    values.reduce((sum, v) => sum + Math.pow(v - mean, 2), 0) / values.length;
+  // Коэффициент вариации
+  return Math.max(0, 1 - Math.sqrt(variance) / mean); // 0..1, где 1 = идеально стабильно
+}
+
+const ORANGE_500: [number, number, number] = [249, 215, 22]; // #f97316
+const GRAY: [number, number, number] = [50, 50, 50];
+
+// Helper function to convert an RGB array to a CSS rgb() string
+const toRgbString = (color: [number, number, number]): string =>
+  `rgb(${color[0]},${color[1]},${color[2]})`;
+
+function getActivityColor(freq: number, rms: number): string {
+  let fromRgb: [number, number, number];
+  let toRgb: [number, number, number];
+
+  if (rms > LOUDNESS_THRESHOLD) {
+    const factor = (freq - MIN_FREQUENCY) / (MAX_FREQUENCY - MIN_FREQUENCY);
+    fromRgb = [
+      Math.round(ORANGE_500[0] * factor),
+      ORANGE_500[1],
+      Math.round(255 - (255 - ORANGE_500[2]) * factor),
+    ];
+    toRgb = fromRgb;
+  } else {
+    fromRgb = GRAY;
+    toRgb = GRAY;
+  }
+
+  // Return a CSS linear-gradient string
+  return `linear-gradient(to right, ${toRgbString(fromRgb)}, ${toRgbString(toRgb)})`;
+}
+
+export const FrequencyCurrentDisplay = memo(function FrequencyCurrentDisplay({
+  latest,
+  history,
+  windowMs,
+}: Props) {
+  const recentHistory = useMemo(() => {
+    if (!latest) return [];
+    const cutoff = latest.timeMs - HISTORY_WINDOW_MS;
+    return history.filter((s) => s.timeMs >= cutoff);
+  }, [latest?.timeMs, history]);
+
+  const stability = useMemo(() => getStability(recentHistory), [recentHistory]);
+  const note = latest ? freqToNote(latest.freq_hz) : "--";
+  const gradientColor = latest
+    ? getActivityColor(latest.freq_hz, latest.rms_db)
+    : "from-slate-400";
+
+  const chartData = useMemo(() => {
+    return recentHistory.map((s) => ({
+      timeMs: s.timeMs,
+      freq_hz: s.freq_hz,
+    }));
+  }, [recentHistory]);
+
+  return (
+    <Card className="col-span-full lg:col-span-1">
+      <CardHeader className="pb-3">
+        <CardTitle className="text-lg">Текущая частота</CardTitle>
+      </CardHeader>
+
+      <CardContent className="space-y-4">
+        {/* Центральный круглый индикатор */}
+        <div className="flex flex-col items-center space-y-2">
+          <div className="relative">
+            {/* Фон круга */}
+            <div
+              className="w-32 h-32 rounded-full border-8 border-slate-200 dark:border-slate-800 shadow-lg"
+              style={{
+                background: `radial-gradient(circle at center, hsl(var(--background)) 0%, hsl(var(--muted)) 100%)`,
+              }}
+            />
+
+            {/* Градиентный круг по активности */}
+            {latest && (
+              <div
+                className={`absolute inset-0 w-32 h-32 rounded-full border-8 animate-spin-slow border-transparent bg-gradient-to-r opacity-70`}
+                style={{
+                  background: gradientColor,
+                  mask: "radial-gradient(circle at center, black 60%, transparent 70%)",
+                  WebkitMask:
+                    "radial-gradient(circle at center, black 60%, transparent 70%)",
+                }}
+              />
+            )}
+
+            {/* Центральный текст */}
+            <div className="absolute inset-0 flex flex-col items-center justify-center">
+              <div className="text-3xl font-bold tabular-nums text-foreground">
+                {latest ? `${latest.freq_hz.toFixed(0)}` : "---"}
+              </div>
+              <div className="text-xs font-medium text-muted-foreground tracking-wide uppercase">
+                Hz
+              </div>
+              <div className="text-xs font-mono bg-background/80 px-2 py-0.5 rounded-full mt-1">
+                {note}
+              </div>
+            </div>
+          </div>
+
+          {/* Стабильность */}
+          <div className="flex items-center gap-2 text-xs">
+            <div
+              className="w-2 h-2 rounded-full"
+              style={{ backgroundColor: `hsl(${240 * stability}, 70%, 50%)` }}
+            />Текущая частота</div>
+        </div>
+
+        {/* Мини-график последних 15 секунд */}
+        <div className="space-y-1">
+          <div className="flex items-center justify-between text-xs text-muted-foreground">
+            <span>Последние изменения ({Math.round(HISTORY_WINDOW_MS / 1000)}с)</span>
+            <span>{recentHistory.length} pts</span>
+          </div>
+          <div className="h-20">
+            <ResponsiveContainer width="100%" height="100%">
+              <LineChart
+                data={chartData}
+                margin={{ top: 0, right: 0, left: 0, bottom: 0 }}
+              >
+                <defs>
+                  <linearGradient id="freqTrend" x1="0" y1="0" x2="1" y2="1">
+                    <stop offset="0%" stopColor="#3b82f6" stopOpacity={0.8} />
+                    <stop offset="100%" stopColor="#1d4ed8" stopOpacity={0.4} />
+                  </linearGradient>
+                </defs>
+                <XAxis
+                  dataKey="timeMs"
+                  hide
+                  type="number"
+                  domain={["dataMin", "dataMax"]}
+                />
+                <Tooltip
+                  labelFormatter={(v) => formatTimeHHMMSS(Number(v))}
+                  formatter={(v) => [`${Number(v).toFixed(0)} Hz`, "freq"]}
+                />
+                <Line
+                  type="monotone"
+                  dataKey="freq_hz"
+                  stroke="url(#freqTrend)"
+                  strokeWidth={2}
+                  dot={false}
+                  isAnimationActive={false}
+                />
+              </LineChart>
+            </ResponsiveContainer>
+          </div>
+        </div>
+      </CardContent>
+    </Card>
+  );
+});
diff --git a/services/frontend/src/widgets/audioLive/ui/FrequencyHistoryChart.tsx b/services/frontend/src/widgets/audioLive/ui/FrequencyHistoryChart.tsx
index 195df87..7021c12 100644
--- a/services/frontend/src/widgets/audioLive/ui/FrequencyHistoryChart.tsx
+++ b/services/frontend/src/widgets/audioLive/ui/FrequencyHistoryChart.tsx
@@ -51,14 +51,14 @@ export const FrequencyHistoryChart = memo(function FrequencyHistoryChart({
   return (
     <Card>
       <CardHeader className="pb-2">
-        <CardTitle className="text-base">Frequency</CardTitle>
+        <CardTitle className="text-base">Доминантная частота</CardTitle>
       </CardHeader>
 
       <CardContent>
         <div className="relative h-56 min-h-[14rem] w-full">
           {!hasData && (
             <div className="absolute inset-0 grid place-items-center text-sm text-muted-foreground">
-              No data yet
+              Пока нет данных
             </div>
           )}
 
@@ -89,7 +89,7 @@ export const FrequencyHistoryChart = memo(function FrequencyHistoryChart({
 
               <Tooltip
                 labelFormatter={(v) => formatTimeHHMMSS(Number(v))}
-                formatter={(v) => [`${Number(v).toFixed(0)} Hz`, "freq"]}
+                formatter={(v) => [`${Number(v).toFixed(0)} Гц`, "част."]}
               />
 
               <Line
diff --git a/services/frontend/src/widgets/audioLive/ui/WaveFormDisplay.tsx b/services/frontend/src/widgets/audioLive/ui/WaveFormDisplay.tsx
new file mode 100644
index 0000000..4c7b9ac
--- /dev/null
+++ b/services/frontend/src/widgets/audioLive/ui/WaveFormDisplay.tsx
@@ -0,0 +1,131 @@
+import { memo, useEffect, useRef } from "react";
+import {
+  Card,
+  CardContent,
+  CardHeader,
+  CardTitle,
+} from "../../../shared/ui/card";
+import type { AudioSample } from "../../../entities/audioSample/model/types";
+import { LOUDNESS_THRESHOLD } from "./AudioLiveWidget";
+
+type Props = {
+  latest: AudioSample | null;
+};
+
+// Синтетическая волна: синусоида с частотой freq_hz и амплитудой из rms_db
+function drawSyntheticWaveform(
+  ctx: CanvasRenderingContext2D,
+  width: number,
+  height: number,
+  freqHz: number,
+  rmsDb: number,
+) {
+  ctx.clearRect(0, 0, width, height);
+
+  // Конвертируем dB в амплитуду (0..1)
+  // rms_db диапазон [-50..0], при -50 амплитуда ~0, при 0 амплитуда ~1
+  const amplitude = Math.pow(10, rmsDb / 150); // линейная амплитуда (0..1)
+  const visualAmp = amplitude * (height / 2) * 0.8; // оставляем margin
+
+  // Количество точек на экране
+  const points = width;
+
+  // Частота в Гц -> сколько периодов умещается на экран
+  // Пусть экран = 1 секунда визуально
+  const timeScale = 0.01; // 50 мс на экран
+  const angularFreq = 2 * Math.PI * freqHz * timeScale;
+
+  // Рисуем синусоиду
+  ctx.beginPath();
+  ctx.strokeStyle = "oklch(0.6 0.2 260)"; // синий градиент
+  ctx.lineWidth = 2;
+
+  for (let x = 0; x < points; x++) {
+    const t = x / width; // нормализованное время [0..1]
+    const y = height / 2 + visualAmp * Math.sin(angularFreq * t);
+
+    if (x === 0) {
+      ctx.moveTo(x, y);
+    } else {
+      ctx.lineTo(x, y);
+    }
+  }
+
+  ctx.stroke();
+
+  // Центральная линия (0-уровень)
+  ctx.beginPath();
+  ctx.strokeStyle = "oklch(0.5 0 0 / 0.3)";
+  ctx.lineWidth = 1;
+  ctx.setLineDash([4, 4]);
+  ctx.moveTo(0, height / 2);
+  ctx.lineTo(width, height / 2);
+  ctx.stroke();
+  ctx.setLineDash([]);
+}
+
+export const WaveformDisplay = memo(function WaveformDisplay({
+  latest,
+}: Props) {
+  const canvasRef = useRef<HTMLCanvasElement>(null);
+
+  useEffect(() => {
+    const canvas = canvasRef.current;
+    if (!canvas) return;
+
+    const ctx = canvas.getContext("2d");
+    if (!ctx) return;
+
+    // Подстраиваем размер под DPI (для чёткости на Retina)
+    const dpr = window.devicePixelRatio || 1;
+    const rect = canvas.getBoundingClientRect();
+    canvas.width = rect.width * dpr;
+    canvas.height = rect.height * dpr;
+    ctx.scale(dpr, dpr);
+
+    // Рисуем волну
+    if (latest && latest.rms_db > LOUDNESS_THRESHOLD) {
+      drawSyntheticWaveform(
+        ctx,
+        rect.width,
+        rect.height,
+        latest.freq_hz,
+        latest.rms_db,
+      );
+    } else {
+      // Рисуем линию
+      ctx.clearRect(0, 0, rect.width, rect.height);
+      ctx.strokeStyle = "oklch(0.5 0 0 / 0.2)";
+      ctx.lineWidth = 1;
+      ctx.beginPath();
+      ctx.moveTo(0, rect.height / 2);
+      ctx.lineTo(rect.width, rect.height / 2);
+      ctx.stroke();
+    }
+  }, [latest]);
+
+  return (
+    <Card>
+      <CardHeader className="pb-2">
+        <CardTitle className="text-base">Форма волны</CardTitle>
+      </CardHeader>
+      <CardContent>
+        <div className="relative w-full h-32 bg-slate-50 dark:bg-slate-900 rounded-md overflow-hidden">
+          <canvas
+            ref={canvasRef}
+            className="w-full h-full"
+            style={{ display: "block" }}
+          />
+
+          {/* Метки */}
+          <div className="absolute top-1 left-2 text-xs text-muted-foreground font-mono">
+            {latest ? `${latest.freq_hz.toFixed(0)} Гц` : "---"}
+          </div>
+          <div className="absolute top-1 right-2 text-xs text-muted-foreground font-mono">
+            {latest ? `${latest.rms_db.toFixed(1)} дБ` : "---"}
+          </div>
+        </div>
+      </CardContent>
+    </Card>
+  );
+});