import shutil
import tempfile
import os
from fastapi import FastAPI, File, UploadFile, HTTPException
from fastapi.responses import HTMLResponse, JSONResponse, Response
from fastapi.staticfiles import StaticFiles
from main import analyze_pdf

app = FastAPI()

# serve index.html at root
@app.get("/", response_class=HTMLResponse)
async def read_root():
    with open("index.html", "r") as f:
        return f.read()

@app.post("/analyze")
async def analyze_endpoint(file: UploadFile = File(...)):
    if not file.filename.endswith(".pdf"):
        raise HTTPException(status_code=400, detail="File must be a PDF")

    # Save to a known fixed path for the viewing endpoint
    # Note: This is not thread-safe/multi-user safe, but sufficient for this local demo.
    # Using /tmp to avoid permission issues on read-only filesystems (Hugging Face Spaces)
    fixed_path = "/tmp/latest_upload.pdf"
    
    with open(fixed_path, "wb") as f:
        shutil.copyfileobj(file.file, f)

    try:
        result = analyze_pdf(
            pdf_path=fixed_path,
            output_path="", 
            debug_dir="" 
        )
        return JSONResponse(content=result)
    except Exception as e:
        import traceback
        traceback.print_exc()
        raise HTTPException(status_code=500, detail=str(e))

import fitz

@app.get("/pdf/page/{page_num}")
async def get_pdf_page(page_num: int):
    path = "/tmp/latest_upload.pdf"
    if not os.path.exists(path):
        return Response(status_code=404)
    
    try:
        doc = fitz.open(path)
        if page_num < 1 or page_num > doc.page_count:
             doc.close()
             return Response(status_code=404)
        
        page = doc.load_page(page_num - 1)
        # decent resolution for web viewing
        zoom = 150 / 72.0
        mat = fitz.Matrix(zoom, zoom)
        pix = page.get_pixmap(matrix=mat, alpha=False)
        img_bytes = pix.tobytes("png")
        doc.close()
        return Response(content=img_bytes, media_type="image/png")
    except Exception as e:
        print(f"Error serving page: {e}")
        return Response(status_code=500)