from fastapi import FastAPI, Request, HTTPException, Security, BackgroundTasks
from fastapi.middleware.cors import CORSMiddleware
from fastapi.security import APIKeyHeader
from fastapi.responses import StreamingResponse
from pydantic import BaseModel
import comfy_engine
import httpx
import os

app = FastAPI(title="Sparkling Vision Pro API - Backend Engine")

# 🌐 CORS सेटअप: यह बहुत ज़रूरी है ताकि दूसरा स्पेस इसे कॉल कर सके!
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"], # प्रोडक्शन में इसे अपने फ्रंटएंड URL से रिप्लेस कर देना
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# 🛡️ सीक्रेट पासवर्ड
API_KEY = os.getenv("VIVEN_API_KEY", "your_default_password")
header_scheme = APIKeyHeader(name="X-API-Key")

async def verify_key(key: str = Security(header_scheme)):
    if key != API_KEY:
        raise HTTPException(status_code=403, detail="Access Denied! Invalid API Key.")
    return key

class VideoRequest(BaseModel):
    prompt: str
    aspect_ratio: str = "16:9"
    quality: str = "480p"
    frames: int = 81
    fps: int = 16

# ==========================================
# 🚀 FIRE-AND-FORGET API ENDPOINT
# ==========================================
@app.post("/api/generate")
async def generate(req: VideoRequest, bg_tasks: BackgroundTasks, auth: str = Security(verify_key)):
    try:
        task_id, client_id, token, total_nodes = await comfy_engine.queue_prompt(req.dict())
        comfy_engine.init_task(task_id, req.prompt)
        bg_tasks.add_task(comfy_engine.background_watcher, task_id, client_id, token, total_nodes)
        return {"status": "queued", "task_id": task_id, "message": "Task is running in the background."}
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

# ==========================================
# 🗂️ STATUS & HISTORY ENDPOINTS
# ==========================================
@app.get("/api/history")
async def get_history():
    return comfy_engine.load_history()

@app.get("/api/video")
async def proxy_video(request: Request):
    q = request.query_params
    target = f"http://{comfy_engine.COMFY_HOST}/view?{q}"
    async def stream():
        async with httpx.AsyncClient() as client:
            async with client.stream("GET", target, timeout=60.0) as r:
                async for chunk in r.aiter_bytes():
                    yield chunk
    return StreamingResponse(stream(), media_type="video/mp4")

@app.delete("/api/history/{task_id}")
async def delete_history_item(task_id: str):
    import json, os
    if os.path.exists("history.json"):
        with open("history.json", "r", encoding="utf-8") as f:
            data = json.load(f)
        data = [item for item in data if item["id"] != task_id]
        with open("history.json", "w", encoding="utf-8") as f:
            json.dump(data, f, indent=4)
        return {"status": "deleted"}
    return {"status": "not found"}

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=7860)