"""Env-driven configuration.

All settings flow through environment variables so the same image runs in
prod (compose.yml env_file) and tests (monkeypatched envs). No config files.
"""
from __future__ import annotations

import os
from dataclasses import dataclass, field
from pathlib import Path


# Default LAN allowlist mirrors the rules baked into the network: anything
# inside RFC1918 plus loopback. Override with CRAFTING_LAN_CIDRS if a deploy
# wants stricter scoping.
DEFAULT_LAN_CIDRS = (
    "10.0.0.0/8",
    "172.16.0.0/12",
    "192.168.0.0/16",
    "127.0.0.0/8",
    "::1/128",
)


@dataclass(frozen=True)
class Config:
    db_path: Path
    workspace_root: Path
    log_dir: Path
    admin_bearer_path: Path
    max_concurrent_jobs: int
    api_port: int
    api_bind: str
    default_job_timeout_secs: int
    lan_cidrs: tuple[str, ...]
    workspace_gc_interval_secs: int
    workspace_gc_age_secs: int


def load() -> Config:
    cidrs_raw = os.environ.get("CRAFTING_LAN_CIDRS", "").strip()
    if cidrs_raw:
        cidrs = tuple(c.strip() for c in cidrs_raw.split(",") if c.strip())
    else:
        cidrs = DEFAULT_LAN_CIDRS

    return Config(
        db_path=Path(os.environ.get("CRAFTING_DB", "/data/crafting.db")),
        workspace_root=Path(os.environ.get("CRAFTING_WORKSPACE", "/workspace")),
        log_dir=Path(os.environ.get("CRAFTING_LOG_DIR", "/data/jobs")),
        admin_bearer_path=Path(os.environ.get("CRAFTING_ADMIN_BEARER", "/data/admin-bearer.txt")),
        max_concurrent_jobs=int(os.environ.get("CRAFTING_MAX_CONCURRENT", "4")),
        api_port=int(os.environ.get("CRAFTING_PORT", "8810")),
        api_bind=os.environ.get("CRAFTING_BIND", "0.0.0.0"),
        default_job_timeout_secs=int(os.environ.get("CRAFTING_DEFAULT_JOB_TIMEOUT", "1800")),
        lan_cidrs=cidrs,
        workspace_gc_interval_secs=int(os.environ.get("CRAFTING_GC_INTERVAL", "3600")),
        workspace_gc_age_secs=int(os.environ.get("CRAFTING_GC_AGE", "86400")),
    )