fix: support blank env values and windows local audio

src/audio/local-voice-session.ts

@@ -1,7 +1,11 @@
-import { spawn, type ChildProcessByStdio } from "node:child_process";
+import { spawn, type ChildProcess, type ChildProcessByStdio } from "node:child_process";
 import { once } from "node:events";
+import { promises as fs } from "node:fs";
+import os from "node:os";
+import path from "node:path";
 import type { Readable, Writable } from "node:stream";
 
+import ffmpegStatic from "ffmpeg-static";
 import { RealTimeVAD } from "avr-vad";
 
 import type { AssistantRuntimeConfig } from "../config.js";
@@ -32,7 +36,7 @@ export class LocalVoiceSession {
 
   private vad: RealTimeVAD | null = null;
   private recorder: ChildProcessByStdio<null, Readable, Readable> | null = null;
-  private currentPlayer: ChildProcessByStdio<Writable, null, Readable> | null = null;
+  private currentPlayer: ChildProcess | null = null;
   private currentAbortController: AbortController | null = null;
   private currentPlayback: PreparedSpeechAudio | null = null;
   private processing = Promise.resolve();
@@ -114,14 +118,19 @@ export class LocalVoiceSession {
   statusSummary(): string {
     return [
       "모드: local",
+      `플랫폼: ${process.platform}`,
       `입력 source: ${this.options.config.LOCAL_AUDIO_SOURCE ?? "default"}`,
-      `출력 sink: ${this.options.config.LOCAL_AUDIO_SINK ?? "default"}`,
+      `출력 sink: ${this.describeSink()}`,
       `대기열: ${this.queue.length}`,
       `최근 대화 턴: ${this.memory.recentTurns().length}`,
     ].join("\n");
   }
 
   private spawnRecorder(): ChildProcessByStdio<null, Readable, Readable> {
+    if (process.platform === "win32") {
+      return this.spawnWindowsRecorder();
+    }
+
     const args = [
       "--rate",
       "16000",
@@ -147,6 +156,40 @@ export class LocalVoiceSession {
     });
   }
 
+  private spawnWindowsRecorder(): ChildProcessByStdio<null, Readable, Readable> {
+    const ffmpegPath = this.getFfmpegPath();
+    const sourceName = this.options.config.LOCAL_AUDIO_SOURCE;
+    if (!sourceName) {
+      throw new Error("Windows 로컬 모드는 LOCAL_AUDIO_SOURCE 설정이 필요합니다. `bun run audio:devices` 로 이름을 확인해 주세요.");
+    }
+
+    const args = [
+      "-hide_banner",
+      "-loglevel",
+      "warning",
+      "-f",
+      "dshow",
+      "-i",
+      `audio=${sourceName}`,
+      "-ac",
+      "1",
+      "-ar",
+      "16000",
+      "-f",
+      "s16le",
+      "pipe:1",
+    ];
+
+    this.options.logger.info("Starting local recorder", {
+      source: sourceName,
+      backend: "ffmpeg-dshow",
+    });
+
+    return spawn(ffmpegPath, args, {
+      stdio: ["ignore", "pipe", "pipe"],
+    });
+  }
+
   private pushPcm16Chunk(chunk: Buffer): void {
     if (this.destroyed || !this.vad) {
       return;
@@ -284,6 +327,11 @@ export class LocalVoiceSession {
   }
 
   private async playToSink(playback: PreparedSpeechAudio, signal: AbortSignal): Promise<void> {
+    if (process.platform === "win32") {
+      await this.playToWindowsDefaultSink(playback, signal);
+      return;
+    }
+
     const args = [
       "--rate",
       "48000",
@@ -336,4 +384,120 @@ export class LocalVoiceSession {
       throw new Error(`pw-play exited with code=${code ?? "null"} signal=${playSignal ?? "null"}`);
     }
   }
+
+  private async playToWindowsDefaultSink(playback: PreparedSpeechAudio, signal: AbortSignal): Promise<void> {
+    const chunks: Buffer[] = [];
+
+    await new Promise<void>((resolve, reject) => {
+      playback.stream.on("data", (chunk: Buffer) => {
+        chunks.push(Buffer.from(chunk));
+      });
+      playback.stream.once("end", resolve);
+      playback.stream.once("error", reject);
+      signal.addEventListener(
+        "abort",
+        () => {
+          playback.stream.destroy();
+          reject(new Error("playback aborted"));
+        },
+        { once: true },
+      );
+    }).catch((error) => {
+      if (signal.aborted) {
+        return;
+      }
+      throw error;
+    });
+
+    if (signal.aborted) {
+      return;
+    }
+
+    const pcm = Buffer.concat(chunks);
+    const wav = createWaveFileBuffer(pcm, 48000, 2, 16);
+    const tempPath = path.join(os.tmpdir(), `realtime-voice-bot-${Date.now()}.wav`);
+    await fs.writeFile(tempPath, wav);
+
+    const psScript = [
+      "Add-Type -AssemblyName System;",
+      `$player = New-Object System.Media.SoundPlayer('${tempPath.replace(/'/g, "''")}');`,
+      "$player.PlaySync();",
+    ].join(" ");
+
+    const player = spawn("powershell", ["-NoProfile", "-Command", psScript], {
+      stdio: ["ignore", "ignore", "pipe"],
+    });
+    this.currentPlayer = player;
+
+    player.stderr.on("data", (chunk: Buffer) => {
+      const text = chunk.toString().trim();
+      if (text.length > 0) {
+        this.options.logger.debug("[powershell-player]", text);
+      }
+    });
+
+    signal.addEventListener(
+      "abort",
+      () => {
+        if (!player.killed) {
+          player.kill("SIGKILL");
+        }
+      },
+      { once: true },
+    );
+
+    const [code, playSignal] = (await once(player, "exit")) as [number | null, NodeJS.Signals | null];
+    this.currentPlayer = null;
+    await fs.unlink(tempPath).catch(() => null);
+
+    if (signal.aborted) {
+      return;
+    }
+
+    if (code !== 0) {
+      throw new Error(`powershell playback exited with code=${code ?? "null"} signal=${playSignal ?? "null"}`);
+    }
+  }
+
+  private getFfmpegPath(): string {
+    const ffmpegPath = ffmpegStatic as unknown as string | null;
+    if (!ffmpegPath) {
+      throw new Error("ffmpeg-static 경로를 찾지 못했습니다.");
+    }
+    return ffmpegPath;
+  }
+
+  private describeSink(): string {
+    if (process.platform === "win32") {
+      return this.options.config.LOCAL_AUDIO_SINK ?? "system-default";
+    }
+    return this.options.config.LOCAL_AUDIO_SINK ?? "default";
+  }
+}
+
+function createWaveFileBuffer(
+  pcm: Buffer,
+  sampleRate: number,
+  channels: number,
+  bitsPerSample: number,
+): Buffer {
+  const header = Buffer.alloc(44);
+  const byteRate = sampleRate * channels * (bitsPerSample / 8);
+  const blockAlign = channels * (bitsPerSample / 8);
+
+  header.write("RIFF", 0, 4, "ascii");
+  header.writeUInt32LE(36 + pcm.length, 4);
+  header.write("WAVE", 8, 4, "ascii");
+  header.write("fmt ", 12, 4, "ascii");
+  header.writeUInt32LE(16, 16);
+  header.writeUInt16LE(1, 20);
+  header.writeUInt16LE(channels, 22);
+  header.writeUInt32LE(sampleRate, 24);
+  header.writeUInt32LE(byteRate, 28);
+  header.writeUInt16LE(blockAlign, 32);
+  header.writeUInt16LE(bitsPerSample, 34);
+  header.write("data", 36, 4, "ascii");
+  header.writeUInt32LE(pcm.length, 40);
+
+  return Buffer.concat([header, pcm]);
 }