from iptocc import country_code

# ISO 3166-1 alpha-2 to country name (common ones)
COUNTRY_NAMES = {
    "CN": "中国", "US": "美国", "NG": "尼日利亚", "GH": "加纳",
    "KE": "肯尼亚", "TZ": "坦桑尼亚", "ZA": "南非", "EG": "埃及",
    "AE": "阿联酋", "SA": "沙特阿拉伯", "IQ": "伊拉克", "JO": "约旦",
    "PK": "巴基斯坦", "BD": "孟加拉国", "IN": "印度", "TH": "泰国",
    "VN": "越南", "ID": "印尼", "PH": "菲律宾", "MY": "马来西亚",
    "JP": "日本", "KR": "韩国", "GB": "英国", "DE": "德国",
    "FR": "法国", "RU": "俄罗斯", "BR": "巴西", "MX": "墨西哥",
    "AU": "澳大利亚", "CA": "加拿大", "TR": "土耳其", "IR": "伊朗",
    "MM": "缅甸", "KH": "柬埔寨", "LA": "老挝", "LK": "斯里兰卡",
    "NP": "尼泊尔", "UG": "乌干达", "ET": "埃塞俄比亚", "SN": "塞内加尔",
    "CI": "科特迪瓦", "CM": "喀麦隆", "CD": "刚果(金)", "MZ": "莫桑比克",
}


def resolve_country(ip: str) -> str:
    if not ip or ip in ("127.0.0.1", "::1", "localhost"):
        return "本地"
    try:
        code = country_code(ip)
        if code and code != "--":
            return COUNTRY_NAMES.get(code, code)
        return "未知"
    except Exception:
        return "未知"


def resolve_region_code(ip: str) -> str | None:
    """解析 ip 为 ISO 3166-1 alpha-2 国家码（如 "US"），查不到返回 None。

    与 resolve_country 的分工：resolve_country 返回中文名（含"本地"/"未知"
    兜底占位，仅供展示/记录）；本函数返回 ISO alpha-2 或 None，供电话区号
    推断等逻辑消费——绝无中文或占位值，调用方无需再过滤。
    """
    if not ip or ip in ("127.0.0.1", "::1", "localhost"):
        return None
    try:
        code = country_code(ip)
        if code and code != "--":
            return code
        return None
    except Exception:
        return None