from datetime import datetime, timedelta
from typing import Optional, Dict, Any
from jose import JWTError, jwt
from passlib.context import CryptContext
from app.core.config import settings
import secrets
import hashlib


pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")


def verify_password(plain_password: str, hashed_password: str) -> bool:
    """
    بررسی صحت رمز عبور
    """
    return pwd_context.verify(plain_password, hashed_password)


def get_password_hash(password: str) -> str:
    """
    هش کردن رمز عبور
    """
    return pwd_context.hash(password)


def create_access_token(data: Dict[str, Any], expires_delta: Optional[timedelta] = None) -> str:
    """
    ایجاد توکن دسترسی JWT
    """
    to_encode = data.copy()
    
    if expires_delta:
        expire = datetime.utcnow() + expires_delta
    else:
        expire = datetime.utcnow() + timedelta(minutes=settings.ACCESS_TOKEN_EXPIRE_MINUTES)
    
    to_encode.update({"exp": expire, "type": "access"})
    encoded_jwt = jwt.encode(to_encode, settings.SECRET_KEY, algorithm=settings.ALGORITHM)
    return encoded_jwt


def create_refresh_token(data: Dict[str, Any]) -> str:
    """
    ایجاد توکن رفرش
    """
    to_encode = data.copy()
    expire = datetime.utcnow() + timedelta(days=settings.REFRESH_TOKEN_EXPIRE_DAYS)
    to_encode.update({"exp": expire, "type": "refresh"})
    encoded_jwt = jwt.encode(to_encode, settings.SECRET_KEY, algorithm=settings.ALGORITHM)
    return encoded_jwt


def verify_token(token: str) -> Optional[Dict[str, Any]]:
    """
    بررسی اعتبار توکن
    """
    try:
        payload = jwt.decode(token, settings.SECRET_KEY, algorithms=[settings.ALGORITHM])
        return payload
    except JWTError:
        return None


def generate_session_id() -> str:
    """
    ایجاد شناسه منحصربه‌فرد برای سشن
    """
    return secrets.token_urlsafe(32)


def generate_confirmation_code() -> str:
    """
    ایجاد کد تأیید برای اقدامات پرریسک
    """
    return hashlib.sha256(secrets.token_bytes(32)).hexdigest()[:8].upper()


def validate_password_strength(password: str) -> Dict[str, bool]:
    """
    بررسی قدرت رمز عبور
    """
    return {
        "length": len(password) >= 8,
        "lowercase": any(c.islower() for c in password),
        "uppercase": any(c.isupper() for c in password),
        "digit": any(c.isdigit() for c in password),
        "special": any(not c.isalnum() for c in password),
    }
