add hermes tts playback (#541)

packages/server/src/controllers/hermes/tts.ts

@@ -0,0 +1,28 @@
+import type { Context } from 'koa'
+import { textToSpeech } from '../../services/hermes/tts'
+
+export async function generate(ctx: Context) {
+  const { text, lang } = ctx.request.body as {
+    text?: string
+    lang?: string
+  }
+
+  if (!text || typeof text !== 'string') {
+    ctx.status = 400
+    ctx.body = { error: 'text is required' }
+    return
+  }
+
+  if (text.length > 5000) {
+    ctx.status = 400
+    ctx.body = { error: 'text is too long (max 5000 characters)' }
+    return
+  }
+
+  const { audio, engine } = await textToSpeech({ text, lang })
+
+  ctx.set('Content-Type', 'audio/mpeg')
+  ctx.set('Content-Length', String(audio.length))
+  ctx.set('X-TTS-Engine', engine)
+  ctx.body = audio
+}