"""
加密与指纹生成工具模块

提供以下功能:
- 生成 OpenAI 设备 ID (oai-did)
- 生成符合要求的强密码
- Proof of Work 挑战解决（预留接口）
"""

import uuid
import secrets
import string
from typing import Optional


def generate_oai_did() -> str:
    """
    生成 OpenAI 设备 ID

    使用 UUIDv4 格式，例如：
    "a1b2c3d4-e5f6-4789-a012-b3c4d5e6f7a8"

    返回:
        36 个字符的 UUID 字符串（包含 4 个连字符）
    """
    return str(uuid.uuid4())


def generate_random_password(length: int = 12) -> str:
    """
    生成符合 OpenAI 要求的强密码

    要求:
    - 长度：8-16 位（默认 12 位）
    - 必须包含：大写字母、小写字母、数字
    - 不包含特殊符号（避免编码问题）

    参数:
        length: 密码长度（默认 12）

    返回:
        符合要求的随机密码
    """
    if length < 8 or length > 16:
        raise ValueError("Password length must be between 8 and 16")

    # 字符集：大写字母 + 小写字母 + 数字
    chars = string.ascii_letters + string.digits

    # 重复生成直到满足所有条件
    max_attempts = 100
    for _ in range(max_attempts):
        password = ''.join(secrets.choice(chars) for _ in range(length))

        # 验证条件
        has_lower = any(c.islower() for c in password)
        has_upper = any(c.isupper() for c in password)
        has_digit = any(c.isdigit() for c in password)

        if has_lower and has_upper and has_digit:
            return password

    # 如果随机生成失败，手动构造一个符合要求的密码
    # 确保至少有一个大写、一个小写、一个数字
    parts = [
        secrets.choice(string.ascii_uppercase),  # 至少一个大写
        secrets.choice(string.ascii_lowercase),  # 至少一个小写
        secrets.choice(string.digits),           # 至少一个数字
    ]

    # 填充剩余长度
    remaining = length - len(parts)
    parts.extend(secrets.choice(chars) for _ in range(remaining))

    # 打乱顺序
    password_list = list(parts)
    for i in range(len(password_list) - 1, 0, -1):
        j = secrets.randbelow(i + 1)
        password_list[i], password_list[j] = password_list[j], password_list[i]

    return ''.join(password_list)


def generate_proof_of_work(seed: str, difficulty: str, **kwargs) -> str:
    """
    解决 Sentinel 的 Proof of Work 挑战


    参数:
        seed: PoW 种子值
        difficulty: 难度参数
        **kwargs: 其他可能需要的参数

    返回:
        PoW 答案字符串

    抛出:
        NotImplementedError: 用户需要实现此方法
    """
    raise NotImplementedError(
        "Proof of Work solver not implemented. "
        "User has existing Sentinel solution that should be integrated here.\n"
        "Integration options:\n"
        "1. Call external script/service\n"
        "2. Import existing Python module\n"
        "3. HTTP API call to solver service"
    )


def validate_oai_did(oai_did: str) -> bool:
    """
    验证 oai-did 格式是否正确

    参数:
        oai_did: 待验证的设备 ID

    返回:
        True 如果格式正确，否则 False
    """
    try:
        # 尝试解析为 UUID
        uuid_obj = uuid.UUID(oai_did)
        # 验证是 UUIDv4
        return uuid_obj.version == 4
    except (ValueError, AttributeError):
        return False


def validate_password(password: str) -> tuple[bool, Optional[str]]:
    """
    验证密码是否符合 OpenAI 要求

    参数:
        password: 待验证的密码

    返回:
        (是否有效, 错误信息)
    """
    if len(password) < 8 or len(password) > 16:
        return False, "Password must be 8-16 characters"

    if not any(c.islower() for c in password):
        return False, "Password must contain at least one lowercase letter"

    if not any(c.isupper() for c in password):
        return False, "Password must contain at least one uppercase letter"

    if not any(c.isdigit() for c in password):
        return False, "Password must contain at least one digit"

    return True, None


# 导出主要接口
__all__ = [
    "generate_oai_did",
    "generate_random_password",
    "generate_proof_of_work",
    "validate_oai_did",
    "validate_password",
]