"""Application configuration (env-overridable). No third-party data egress."""
from __future__ import annotations

import os
from pathlib import Path

BASE_DIR = Path(__file__).resolve().parent.parent      # .../backend
DATA_DIR = Path(os.environ.get("AR_DATA_DIR", str(BASE_DIR / "data")))
UPLOAD_DIR = DATA_DIR / "uploads"
EXPORT_DIR = DATA_DIR / "exports"
DB_PATH = Path(os.environ.get("AR_DB_PATH", str(DATA_DIR / "ar_aging.db")))

# Retention: temp uploads/exports older than this are purged (0 = keep forever).
RETENTION_DAYS = int(os.environ.get("AR_RETENTION_DAYS", "30"))

# Defaults
DEFAULT_CLEARING_LAG_DAYS = int(os.environ.get("AR_CLEARING_LAG_DAYS", "2"))
DEFAULT_TOLERANCE = float(os.environ.get("AR_TOLERANCE", "0.01"))

MAX_UPLOAD_BYTES = int(os.environ.get("AR_MAX_UPLOAD_BYTES", str(2 * 1024 * 1024 * 1024)))  # 2 GB
ALLOWED_EXTENSIONS = {".xlsx", ".xls", ".csv"}

# CORS (frontend dev server)
CORS_ORIGINS = os.environ.get(
    "AR_CORS_ORIGINS", "http://localhost:5173,http://127.0.0.1:5173"
).split(",")


def ensure_dirs() -> None:
    for d in (DATA_DIR, UPLOAD_DIR, EXPORT_DIR):
        d.mkdir(parents=True, exist_ok=True)