#!/usr/bin/env python3
import argparse, os, sys
try:
    import yaml
except Exception as e:
    print("ERROR: PyYAML is required. Install with: pip install pyyaml", file=sys.stderr)
    sys.exit(2)

def main():
    p = argparse.ArgumentParser(description="Add a host to inventory/servers.yaml")
    p.add_argument("--name", required=True)
    p.add_argument("--type", default="cpx11")
    p.add_argument("--region", default="nbg1")
    p.add_argument("--role", default="test")
    p.add_argument("--image", default="ubuntu-24.04")
    p.add_argument("--user", default="admin")
    p.add_argument(
        "--reuse-existing",
        action="store_true",
        help="succeed only when an existing record exactly matches the request",
    )
    args = p.parse_args()

    inv_path = os.path.join("inventory", "servers.yaml")
    data = {}
    if os.path.exists(inv_path):
        with open(inv_path, "r", encoding="utf-8") as f:
            data = yaml.safe_load(f) or {}
    servers = data.setdefault("servers", [])

    candidate = {
        "name": args.name,
        "provider": "hetzner",
        "lifecycle_mode": "provider-managed",
        "ssh_user": args.user,
        "baseline_profile": "ufw-managed",
        "provisioning": {
            "server_type": args.type,
            "region": args.region,
            "role": args.role,
            "image": args.image,
            "labels": [],
        },
    }
    existing = next((s for s in servers if s.get("name") == args.name), None)
    if existing is not None:
        if args.reuse_existing and existing == candidate:
            print(f"Reusing matching host '{args.name}' from {inv_path}")
            return
        print(
            f"ERROR: host '{args.name}' already exists with a different declaration",
            file=sys.stderr,
        )
        sys.exit(1)

    data.setdefault("schema_version", "1.0")
    servers.append(candidate)

    with open(inv_path, "w", encoding="utf-8") as f:
        yaml.safe_dump(data, f, sort_keys=False)

if __name__ == "__main__":
    main()