server.py

import asyncio
import os
import ffmpeg
from fastapi import FastAPI, WebSocket, WebSocketDisconnect
from fastapi.responses import HTMLResponse
from fastapi.staticfiles import StaticFiles
from dotenv import load_dotenv
from translator import VoiceTranslator

load_dotenv()

app = FastAPI()
#app.mount("/static", StaticFiles(directory="static"), name="static")

# Load environment variables for API keys
google_creds = os.getenv("GOOGLE_APPLICATION_CREDENTIALS")
deepl_key = os.getenv("DEEPL_API_KEY")
eleven_key = os.getenv("ELEVENLABS_API_KEY")
voice_id = os.getenv("ELEVENLABS_VOICE_ID")

# --- Start Debug Prints ---
print("--- API Key Status ---")
print(f"GOOGLE_APPLICATION_CREDENTIALS loaded: {bool(google_creds)}")
print(f"DEEPL_API_KEY loaded: {bool(deepl_key)}")
print(f"ELEVENLABS_API_KEY loaded: {bool(eleven_key)}")
print(f"ELEVENLABS_VOICE_ID loaded: {bool(voice_id)}")
print("----------------------")

if not all([google_creds, deepl_key, eleven_key, voice_id]):
    raise ValueError("CRITICAL: Missing one or more required API keys. Please check your Hugging Face secrets.")

translator = VoiceTranslator(deepl_key, eleven_key, voice_id)

@app.get("/")
async def get():
    return HTMLResponse(open("index.html", "r").read())

async def audio_output_sender(ws: WebSocket, output_queue: asyncio.Queue):
    print("Audio output sender started.")
    while True:
        try:
            audio_chunk = await output_queue.get()
            if audio_chunk is None:
                break
            await ws.send_bytes(audio_chunk)
        except asyncio.CancelledError:
            break
    print("Audio output sender stopped.")

async def handle_audio_input(websocket: WebSocket, input_queue: asyncio.Queue):
    print("Audio input handler started.")
    while True:
        try:
            data = await websocket.receive_bytes()
            # Use ffmpeg to convert webm/opus audio from browser to raw pcm
            process = (
                ffmpeg
                .input('pipe:0')
                .output('pipe:1', format='s16le', acodec='pcm_s16le', ac=1, ar='16k')
                .run_async(pipe_stdin=True, pipe_stdout=True, pipe_stderr=True)
            )
            
            # Write the audio data to ffmpeg's stdin and close it
            process.stdin.write(data)
            process.stdin.close()
            
            # Read the converted PCM data from ffmpeg's stdout
            pcm_data = process.stdout.read()
            await input_queue.put(pcm_data)
        except WebSocketDisconnect:
            break
        except Exception as e:
            print(f"Audio input error: {e}")
            break
    print("Audio input handler stopped.")


@app.websocket("/ws") # This was correct, the error was in the old HTML. No change needed here, but confirming it's /ws.
async def websocket_endpoint(websocket: WebSocket):
    print("[SERVER] WebSocket endpoint called. Awaiting connection...")
    await websocket.accept()
    print("[SERVER] WebSocket connection accepted.")

    output_sender_task = None
    input_handler_task = None

    try:
        # Start translation and audio processing tasks
        print("[SERVER] Awaiting translator.start_translation()...")
        await translator.start_translation()
        print("[SERVER] translator.start_translation() returned. Creating tasks...")
        output_sender_task = asyncio.create_task(
            audio_output_sender(websocket, translator.output_queue)
        )
        input_handler_task = asyncio.create_task(
            handle_audio_input(websocket, translator.input_queue)
        )

        print("[SERVER] Awaiting asyncio.gather for I/O tasks...")
        await asyncio.gather(input_handler_task, output_sender_task)

    except WebSocketDisconnect:
        print("[SERVER] Client disconnected via WebSocketDisconnect.")
    except Exception as e:
        print(f"[SERVER] An error occurred in websocket_endpoint: {e}")
    finally:
        print("[SERVER] Cleaning up tasks and stopping translation...")
        if output_sender_task:
            output_sender_task.cancel()
        if input_handler_task:
            input_handler_task.cancel()
        translator.stop_translation()
        await websocket.close()
        print("[SERVER] WebSocket connection closed.")