"""Configuration loader.

Reads from the path in FESTER_CONFIG env var if set, otherwise from
config.yaml in the project root. Provides CONFIG as a module-level dict.

F-06 / F-17 remediation:
  External-service endpoints (MinIO, Prometheus, Firecracker SSH key,
  default node host) are now resolved from environment variables with
  sensible fallbacks — no hardcoded ``localhost:9000`` /
  ``http://localhost:9090`` / ``/root/.ssh/fc_builder`` literals in
  the runtime modules. Operators override via env vars; the YAML
  config can still set them under ``CONFIG["external"]``.
"""

import os
from pathlib import Path

import yaml

BASE_DIR = os.path.dirname(os.path.dirname(__file__))

# Allow override via env var (for tests / dev / multi-cluster setups)
_env_config = os.environ.get("FESTER_CONFIG")
if _env_config:
    CONFIG_PATH = _env_config
else:
    CONFIG_PATH = os.path.join(BASE_DIR, "config.yaml")

# Graceful fallback: if the requested config doesn't exist, use a sensible
# default so the backend can still boot (e.g. in a fresh clone or container).
if not Path(CONFIG_PATH).exists():
    CONFIG = {
        "master": {"name": "fester-master", "role": "control"},
        "nodes": [
            {
                "name": os.environ.get("FESTER_NODE_NAME", "localhost"),
                "host": os.environ.get("FESTER_NODE_HOST", "127.0.0.1"),
                "max_jobs": int(os.environ.get("FESTER_NODE_MAX_JOBS", "4")),
            },
        ],
        "projects": [],
        "btc": {
            "enabled": True,
            "root": "/opt/BTC",
            "primary": False,
        },
    }
else:
    with open(CONFIG_PATH, "r") as f:
        CONFIG = yaml.safe_load(f) or {}

# Ensure required keys exist
CONFIG.setdefault("master", {"name": "fester-master", "role": "control"})
CONFIG.setdefault("nodes", [])
CONFIG.setdefault("projects", [])

# BTC (Build Tool Chain) configuration
CONFIG.setdefault("btc", {})
CONFIG["btc"].setdefault("enabled", True)
CONFIG["btc"].setdefault("root", "/opt/BTC")
CONFIG["btc"].setdefault("primary", False)


# ---------------------------------------------------------------------
# External-service endpoints (F-06 / F-17)
# ---------------------------------------------------------------------
# Single source of truth for every external service Fester talks to.
# Modules import EXTERNAL_CONFIG instead of hardcoding URLs / paths.
def _env_bool(name: str, default: bool = False) -> bool:
    return os.environ.get(name, "").lower() in ("1", "true", "yes", "on")


EXTERNAL_CONFIG: dict = {
    # MinIO build cache
    "minio_endpoint":   os.environ.get("FESTER_MINIO_ENDPOINT", "localhost:9000"),
    "minio_access_key": os.environ.get("FESTER_MINIO_ACCESS_KEY", ""),
    "minio_secret_key": os.environ.get("FESTER_MINIO_SECRET_KEY", ""),
    "minio_bucket":     os.environ.get("FESTER_MINIO_BUCKET", "fester-cache"),
    "minio_secure":     _env_bool("FESTER_MINIO_SECURE", False),
    "minio_required":   _env_bool("FESTER_MINIO_REQUIRED", False),

    # Prometheus
    "prometheus_url": os.environ.get(
        "FESTER_PROM_URL", os.environ.get("PROM_URL", "http://localhost:9090"),
    ),

    # Firecracker
    "firecracker_bin":    os.environ.get("FESTER_FIRECRACKER_BIN", "firecracker"),
    "firecracker_ssh_key": os.environ.get(
        "FESTER_FC_SSH_KEY", "/root/.ssh/fc_builder",
    ),
    "firecracker_socket_dir": os.environ.get(
        "FESTER_FC_SOCKET_DIR", "/run/fester/firecracker",
    ),

    # Cluster agent
    "agent_port": int(os.environ.get("FESTER_AGENT_PORT", "8787")),
}


def get_external() -> dict:
    """Return a deep copy of the external-service config dict.

    Returned at call time so tests / operators can monkey-patch env
    vars between requests.
    """
    return dict(EXTERNAL_CONFIG)