from __future__ import annotations

import os
from pathlib import Path

from .settings import DdnsSettings


def settings_from_env() -> DdnsSettings:
    return DdnsSettings(
        database_path=Path(os.getenv("DDNS_DATABASE", "ddns.sqlite3")),
        admin_password=os.getenv("DDNS_ADMIN_PASSWORD", ""),
        admin_path=os.getenv("DDNS_ADMIN_PATH", "/admin"),
        public_base_url=os.getenv("DDNS_PUBLIC_BASE_URL", "http://localhost:8080"),
        trusted_hosts=_csv_set("DDNS_TRUSTED_HOSTS"),
        hostname_suffix=os.getenv("DDNS_HOSTNAME_SUFFIX", ""),
        rate_limit_per_minute=_env_int("DDNS_RATE_LIMIT_PER_MINUTE", 60),
        admin_rate_limit_per_minute=_env_int("DDNS_ADMIN_RATE_LIMIT_PER_MINUTE", 20),
        max_request_body_bytes=_env_int("DDNS_MAX_REQUEST_BODY_BYTES", 16_384),
        trusted_proxy_ips=_csv_set("DDNS_TRUSTED_PROXY_IPS"),
        rfc2136_server=os.getenv("DDNS_RFC2136_SERVER") or None,
        rfc2136_zone=os.getenv("DDNS_RFC2136_ZONE") or None,
        rfc2136_key_name=os.getenv("DDNS_RFC2136_KEY_NAME") or None,
        rfc2136_key_secret=os.getenv("DDNS_RFC2136_KEY_SECRET") or None,
        dns_provider=os.getenv("DDNS_DNS_PROVIDER", ""),
        dns_zones=_csv_set("DDNS_DNS_ZONES"),
        require_dns_provider=_env_flag("DDNS_REQUIRE_DNS_PROVIDER"),
        cloudflare_api_token=os.getenv("DDNS_CLOUDFLARE_API_TOKEN", ""),
        cloudflare_zone_id=os.getenv("DDNS_CLOUDFLARE_ZONE_ID", ""),
        cleanup_pending_account_hours=_env_int("DDNS_CLEANUP_PENDING_ACCOUNT_HOURS", 24),
        cleanup_unused_account_hours=_env_int("DDNS_CLEANUP_UNUSED_ACCOUNT_HOURS", 1080),
        cleanup_event_history_hours=_env_int("DDNS_CLEANUP_EVENT_HISTORY_HOURS", 24 * 180),
        cleanup_interval_seconds=_env_int("DDNS_CLEANUP_INTERVAL_SECONDS", 3600),
        dashboard_unlock_seconds=_env_int("DDNS_DASHBOARD_UNLOCK_SECONDS", 24 * 60 * 60),
        dashboard_stay_unlocked_seconds=_env_int(
            "DDNS_DASHBOARD_STAY_UNLOCKED_SECONDS",
            30 * 24 * 60 * 60,
        ),
        dashboard_cookie_secret=os.getenv("DDNS_DASHBOARD_COOKIE_SECRET", ""),
        redacted_access_log=_env_flag("DDNS_REDACTED_ACCESS_LOG"),
        ttl=_env_int("DDNS_TTL", 60),
    )


def _csv_set(name: str) -> set[str]:
    return {item.strip().lower() for item in os.getenv(name, "").split(",") if item.strip()}


def _env_flag(name: str) -> bool:
    return os.getenv(name, "0").strip().lower() not in {"0", "false", "no"}


def _env_int(name: str, default: int) -> int:
    try:
        return int(os.getenv(name, str(default)).strip())
    except ValueError as exc:
        raise ValueError(f"{name} must be an integer") from exc