import os
import time
import hmac
import hashlib
import edge_tts
from fastapi import FastAPI, Request
from fastapi.responses import StreamingResponse, JSONResponse
from fastapi.middleware.cors import CORSMiddleware

app = FastAPI(title="VCLOUD Edge TTS API")


app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)


SECRET_KEY = os.environ.get("API_SECRET_KEY")
DEFAULT_VOICE = "vi-VN-HoaiMyNeural"

async def read_tts_payload(request: Request):
    text = ""
    voice = DEFAULT_VOICE
    bot_uid = ""
    req_time = "0"
    token = ""

    if request.method == "POST":
        try:
            data = await request.json()
        except Exception:
            data = {}
        text = str(data.get("text", "")).strip()
        voice = str(data.get("voice", voice)).strip() or DEFAULT_VOICE
        bot_uid = str(data.get("bot_uid", "")).strip()
        req_time = str(data.get("time", "0")).strip()
        token = str(data.get("token", "")).strip()
    else:
        text = request.query_params.get("text", "").strip()
        voice = request.query_params.get("voice", voice).strip() or DEFAULT_VOICE
        bot_uid = request.query_params.get("bot_uid", "").strip()
        req_time = request.query_params.get("time", "0").strip()
        token = request.query_params.get("token", "").strip()
        
    return text, voice, bot_uid, req_time, token

@app.get("/")
async def root():
   
    return JSONResponse({"status": "VCLOUD Voice API is running optimally on Hugging Face!"})

@app.get("/health")
async def healthcheck():
    
    return JSONResponse({"status": "ok", "message": "Trạm Voice đang hoạt động xuất sắc!"})

@app.post("/tts")
@app.get("/tts")
async def generate_tts(request: Request):
    text, voice, bot_uid, req_time, token = await read_tts_payload(request)

   
    if not text:
        return JSONResponse({"status": "success", "message": "Endpoint TTS đã sẵn sàng nhận văn bản."}, status_code=200)

    
    try:
        if not SECRET_KEY:
            return JSONResponse({"error": "Lỗi máy chủ: Chưa cấu hình Secret Key (API_SECRET_KEY) trong Settings!"}, status_code=500)

       
        current_time = int(time.time())
        if current_time - int(req_time) > 43200:
            return JSONResponse({"error": "Truy cập bị từ chối! Token đã hết hạn."}, status_code=401)
        
        
        message = f"{bot_uid}{req_time}".encode('utf-8')
        expected_token = hmac.new(SECRET_KEY.encode('utf-8'), message, hashlib.sha256).hexdigest()
        
        
        if not hmac.compare_digest(expected_token, token):
            return JSONResponse({"error": "Truy cập bị từ chối! Sai Token bảo mật (HMAC không khớp)."}, status_code=403)
            
    except Exception as e:
        return JSONResponse({"error": f"Lỗi xác thực bảo mật: {str(e)}"}, status_code=401)

    
    try:
        communicate = edge_tts.Communicate(text, voice)
        
        async def audio_stream():
            async for chunk in communicate.stream():
                if chunk["type"] == "audio":
                    yield chunk["data"]

        
        return StreamingResponse(audio_stream(), media_type="audio/mpeg")
        
    except Exception as e:
        return JSONResponse({"error": f"Lỗi quá trình tạo âm thanh: {str(e)}"}, status_code=500)