from fastapi import FastAPI, File, UploadFile, HTTPException
from fastapi.responses import JSONResponse
import shutil
import os
import uuid
from backend.pipelines.video_processor import VideoProcessor

app = FastAPI(title="Pothole & Road Sign Detection API")

# Initialize Processor (Loading models takes time, do it on startup)
# In production, use lifespan events or dependency injection
print("Initializing Video Processor...")
try:
    processor = VideoProcessor()
except Exception as e:
    print(f"Warning: Could not initialize processor (Check model paths). Error: {e}")
    processor = None

UPLOAD_DIR = "uploads"
os.makedirs(UPLOAD_DIR, exist_ok=True)

@app.get("/")
def health_check():
    return {"status": "running", "models_loaded": processor is not None}

@app.post("/detect/video")
async def detect_video(file: UploadFile = File(...)):
    if processor is None:
        raise HTTPException(status_code=503, detail="Models not accepted or loaded.")

    # Save uploaded file
    file_id = str(uuid.uuid4())
    file_location = os.path.join(UPLOAD_DIR, f"{file_id}_{file.filename}")
    
    with open(file_location, "wb") as buffer:
        shutil.copyfileobj(file.file, buffer)
        
    try:
        # Run processing
        start_time = os.times().elapsed
        results = processor.process_video(file_location)
        
        # Cleanup
        os.remove(file_location)
        
        return {
            "video_id": file_id,
            "processed": True,
            "unique_objects": results
        }
    except Exception as e:
        # Cleanup on error
        if os.path.exists(file_location):
            os.remove(file_location)
        raise HTTPException(status_code=500, detail=str(e))

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8000)