from fastapi import FastAPI, File, UploadFile, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from detect import detect_pdf

app = FastAPI(title="PDF Field Detector")

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_methods=["POST", "GET"],
    allow_headers=["*"],
)

@app.get("/health")
def health():
    from detect import _ensure_ffdnet, _ffdnet_error
    return {"ok": True, "ffdnet": _ensure_ffdnet(), "ffdnet_error": _ffdnet_error or None}

@app.post("/debug")
async def debug(file: UploadFile = File(...)):
    """Run commonforms and return raw widget count + sample boxes before normalization."""
    import tempfile, os, fitz
    from commonforms import prepare_form
    pdf_bytes = await file.read()
    with tempfile.TemporaryDirectory() as tmp:
        in_p  = os.path.join(tmp, 'in.pdf')
        out_p = os.path.join(tmp, 'out.pdf')
        with open(in_p, 'wb') as f: f.write(pdf_bytes)
        try:
            prepare_form(in_p, out_p, confidence=0.1, device='cpu')
        except Exception as e:
            return {"error": str(e)}
        if not os.path.exists(out_p):
            return {"error": "no output produced"}
        doc = fitz.open(out_p)
        result = []
        for pi, page in enumerate(doc):
            widgets = list(page.widgets())
            result.append({
                "page": pi,
                "widget_count": len(widgets),
                "sample": [{"type": w.field_type, "rect": list(w.rect)} for w in widgets[:5]],
            })
        return {"pages": result, "output_size": os.path.getsize(out_p)}

@app.post("/detect")
async def detect(file: UploadFile = File(...)):
    if not file.filename.lower().endswith(".pdf"):
        raise HTTPException(400, "Only PDF files accepted")
    pdf_bytes = await file.read()
    if len(pdf_bytes) > 50 * 1024 * 1024:
        raise HTTPException(413, "PDF too large (max 50MB)")
    try:
        pages = detect_pdf(pdf_bytes)
        return {"pages": pages}
    except Exception as e:
        raise HTTPException(500, str(e))