from fastapi import FastAPI, UploadFile, Form
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse, RedirectResponse
import shutil, os

app = FastAPI()

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

# ✅ Basic root redirection (optional)
@app.get("/")
def home():
    return RedirectResponse(url="/docs")  # Or to a frontend URL

# ✅ File prediction endpoint
@app.post("/predict")
async def predict(question: str = Form(...), file: UploadFile = Form(...)):
    try:
        temp_path = f"temp_{file.filename}"
        with open(temp_path, "wb") as f:
            shutil.copyfileobj(file.file, f)

        if file.content_type.startswith("image/"):
            from appImage import answer_question_from_image
            from PIL import Image
            image = Image.open(temp_path)
            answer = answer_question_from_image(image, question)
        else:
            from app import answer_question_from_doc
            class NamedFile:
                def __init__(self, name): self.name = name
            answer = answer_question_from_doc(NamedFile(temp_path), question)

        os.remove(temp_path)
        return JSONResponse(content={"answer": answer})

    except Exception as e:
        return JSONResponse(content={"error": str(e)}, status_code=500)