import logging
import os
from datetime import datetime, timezone
from typing import Optional


def utcnow() -> datetime:
    """Return the current UTC time as a timezone-naive datetime.

    SQLite (and SQLAlchemy's default column handling) stores datetimes without
    timezone info. Using this helper keeps all DB timestamps and comparisons
    consistent and avoids TypeError on offset-naive vs offset-aware comparisons.
    """
    return datetime.now(timezone.utc).replace(tzinfo=None)


# ── Paths ─────────────────────────────────────────────────────────────────────
_HERE = os.path.dirname(os.path.abspath(__file__))   # src/core/
_SRC_DIR = os.path.dirname(_HERE)                    # src/
_PROJECT_ROOT = os.path.dirname(_SRC_DIR)             # project root
DATA_DIR: str = os.path.join(_PROJECT_ROOT, "data")

# ── Logging ───────────────────────────────────────────────────────────────────
# LOG_LEVEL: one of DEBUG, INFO, WARNING, ERROR, CRITICAL (default: INFO)
LOG_LEVEL: int = getattr(logging, os.environ.get("LOG_LEVEL", "INFO").upper(), logging.INFO)
# LOG_FILE: set to empty string to disable file logging
LOG_FILE: str = os.environ.get("LOG_FILE", "")

# ── Security ──────────────────────────────────────────────────────────────────
SECRET_KEY: str = os.environ.get("SECRET_KEY") or ""
if not SECRET_KEY:
    raise RuntimeError("SECRET_KEY environment variable must be set")

# ── Database ──────────────────────────────────────────────────────────────────
DATABASE_URL: str = os.environ.get(
    "DATABASE_URL",
    f"sqlite:///{os.path.join(DATA_DIR, 'gates.db')}",
)

# ── CORS ──────────────────────────────────────────────────────────────────────
# Comma-separated list of allowed origins, e.g. "https://example.com,https://app.example.com"
# Default to empty list (no cross-origin requests allowed) when not set.
_cors_env = os.environ.get("CORS_ORIGINS", "")
CORS_ORIGINS: list[str] = [o.strip() for o in _cors_env.split(",") if o.strip()]

# ── Proxy ─────────────────────────────────────────────────────────────────────
# Comma-separated list of trusted reverse-proxy IPs for X-Forwarded-For propagation.
# e.g. "127.0.0.1,10.0.0.1"
_proxy_env = os.environ.get("TRUSTED_PROXY_IPS", "127.0.0.1")
TRUSTED_PROXY_IPS: list[str] = [ip.strip() for ip in _proxy_env.split(",") if ip.strip()]

# ── Admin seed ────────────────────────────────────────────────────────────────
ADMIN_USERNAME: str = os.environ.get("ADMIN_USERNAME", "admin")
ADMIN_PASSWORD: Optional[str] = os.environ.get("ADMIN_PASSWORD") or None

# ── Server ────────────────────────────────────────────────────────────────────
APP_PORT: int = int(os.environ.get("APP_PORT", 8000))

# ── Map / home location ───────────────────────────────────────────────────────
# Optional WGS-84 coordinates for the "home" marker shown on the frontend map.
HOME_LAT: Optional[float] = float(os.environ["HOME_LAT"]) if os.environ.get("HOME_LAT") else None
HOME_LON: Optional[float] = float(os.environ["HOME_LON"]) if os.environ.get("HOME_LON") else None
HOME_NAME: str = os.environ.get("HOME_NAME", "Home")