from fastapi import FastAPI, UploadFile, File, Form, Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import HTMLResponse, JSONResponse, FileResponse
from fastapi.staticfiles import StaticFiles
from fastapi.templating import Jinja2Templates
import os
import tempfile
from typing import Optional

# Initialize FastAPI
app = FastAPI()

# CORS Policy: allow everything (because Hugging Face Spaces needs it open)
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Static files and templates
app.mount("/static", StaticFiles(directory="static"), name="static")
app.mount("/resources", StaticFiles(directory="resources"), name="resources")
templates = Jinja2Templates(directory="templates")

# --- Serve Frontend ---

@app.get("/", response_class=HTMLResponse)
async def serve_home(request: Request):
    return templates.TemplateResponse("HomeS.html", {"request": request})

# --- API Endpoints that frontend needs ---

@app.post("/summarize/")
async def summarize_document_endpoint(file: UploadFile = File(...), length: str = Form("medium")):
    try:
        from app import summarize_api
        return await summarize_api(file, length)
    except Exception as e:
        return JSONResponse({"error": f"Summarization failed: {str(e)}"}, status_code=500)

@app.post("/imagecaption/")
async def caption_image_endpoint(file: UploadFile = File(...)):
    try:
        from appImage import caption_from_frontend
        return await caption_from_frontend(file)
    except Exception as e:
        return JSONResponse({"error": f"Image captioning failed: {str(e)}"}, status_code=500)

# --- Serve generated audio/pdf files ---

@app.get("/files/{filename}")
async def serve_file(filename: str):
    path = os.path.join(tempfile.gettempdir(), filename)
    if os.path.exists(path):
        return FileResponse(path)
    return JSONResponse({"error": "File not found"}, status_code=404)

# (Optional) Unified prediction endpoint — Only if you want
@app.post("/predict")
async def predict(
    file: UploadFile = File(...),
    option: str = Form(...),        # "Summarize" or "Captioning"
    length: Optional[str] = Form(None)  # Only for Summarize
):
    try:
        if option == "Summarize":
            return await summarize_document_endpoint(file, length or "medium")
        elif option == "Captioning":
            return await caption_image_endpoint(file)
        else:
            return JSONResponse({"error": "Invalid option"}, status_code=400)
    except Exception as e:
        return JSONResponse({"error": f"Prediction failed: {str(e)}"}, status_code=500)