"""
安全相关工具 - 使用scrypt替代bcrypt
"""
from datetime import datetime, timedelta
from typing import Any, Union, Optional
from jose import jwt
from passlib.context import CryptContext
from .config import settings

# 使用scrypt替代bcrypt
pwd_context = CryptContext(schemes=["scrypt"], deprecated="auto")

# 获取安全配置
security_settings = settings.security


def create_access_token(
    subject: Union[str, Any], expires_delta: Optional[timedelta] = None
) -> str:
    """
    创建访问令牌
    """
    if expires_delta:
        expire = datetime.utcnow() + expires_delta
    else:
        expire = datetime.utcnow() + timedelta(
            minutes=security_settings.ACCESS_TOKEN_EXPIRE_MINUTES
        )
    to_encode = {"exp": expire, "sub": str(subject)}
    encoded_jwt = jwt.encode(
        to_encode, security_settings.SECRET_KEY, algorithm=security_settings.ALGORITHM
    )
    return encoded_jwt


def verify_password(plain_password: str, hashed_password: str) -> bool:
    """
    验证密码
    """
    # 为避免bcrypt的72字节限制，对密码进行截断处理
    if len(plain_password.encode('utf-8')) > 72:
        plain_password = plain_password.encode('utf-8')[:72].decode('utf-8', errors='ignore')
    return pwd_context.verify(plain_password, hashed_password)


def get_password_hash(password: str) -> str:
    """
    获取密码哈希
    """
    # 为避免bcrypt的72字节限制，对密码进行截断处理
    if len(password.encode('utf-8')) > 72:
        password = password.encode('utf-8')[:72].decode('utf-8', errors='ignore')
    return pwd_context.hash(password)


def verify_token(token: str) -> Optional[str]:
    """
    验证令牌并返回用户ID
    """
    try:
        payload = jwt.decode(
            token, security_settings.SECRET_KEY, algorithms=[security_settings.ALGORITHM]
        )
        user_id: str = payload.get("sub")
        if user_id is None:
            return None
        return user_id
    except jwt.JWTError:
        return None