import yaml

PROXY_FIELDS = {
    "name", "type", "server", "port", "uuid", "password", "cipher",
    "alterId", "tls", "network", "ws-opts", "h2-opts", "http-opts",
    "grpc-opts", "reality-opts", "servername", "fingerprint", "flow",
    "udp", "skip-cert-verify", "sni", "username", "plugin", "plugin-opts",
    "client-fingerprint", "early-data-header-name", "smux",
}


def filter_proxy(proxy: dict) -> dict:
    return {k: v for k, v in proxy.items() if k in PROXY_FIELDS}


def expand_config(base_yaml: str, provider_proxies: dict[str, list[dict]]) -> str:
    cfg = yaml.safe_load(base_yaml) or {}

    all_proxies = list(cfg.get("proxies") or [])
    provider_to_names: dict[str, list[str]] = {}

    for provider_name, proxies in provider_proxies.items():
        filtered = [filter_proxy(p) for p in proxies if "name" in p]
        provider_to_names[provider_name] = [p["name"] for p in filtered]
        all_proxies.extend(filtered)

    cfg["proxies"] = all_proxies

    for group in cfg.get("proxy-groups") or []:
        if "use" in group:
            expanded: list[str] = []
            for pname in group.pop("use"):
                expanded.extend(provider_to_names.get(pname, []))
            group.setdefault("proxies", [])
            group["proxies"] = group["proxies"] + expanded

    cfg.pop("proxy-providers", None)

    return yaml.dump(cfg, allow_unicode=True, sort_keys=False)


def build_mihomo_config(all_base_yamls: list[str], secret: str) -> str:
    providers: dict[str, dict] = {}

    for base_yaml in all_base_yamls:
        try:
            cfg = yaml.safe_load(base_yaml) or {}
            for name, provider in (cfg.get("proxy-providers") or {}).items():
                if name not in providers:
                    providers[name] = provider
        except yaml.YAMLError:
            continue

    config: dict = {
        "external-controller": "0.0.0.0:9090",
        "secret": secret,
        "mixed-port": 7890,
        "allow-lan": False,
    }
    if providers:
        config["proxy-providers"] = providers

    return yaml.dump(config, allow_unicode=True, sort_keys=False)