#auth_services.py
import jwt  
from jwt.exceptions import PyJWTError  
from passlib.context import CryptContext
from datetime import datetime, timedelta
import os
from dotenv import load_dotenv
import secrets
from datetime import datetime, timedelta
from passlib.context import CryptContext
from sqlalchemy.orm import Session
from src.utils.email import send_email
from src.apps.auth.models import PasswordResetToken



# Load environment variables from .env file (if present)
load_dotenv()


# Get SECRET_KEY from environment variables
SECRET_KEY = os.getenv("SECRET_KEY")
if not SECRET_KEY:
    raise ValueError("SECRET_KEY is not set in environment variables!")

ALGORITHM = "HS256"
# ACCESS_TOKEN_EXPIRE_MINUTES = 120
ACCESS_TOKEN_EXPIRE_MINUTES = 60 * 24 * 7

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

def hash_password(password: str) -> str:
    """Hash a password using bcrypt."""
    return pwd_context.hash(password)

def verify_password(plain_password: str, hashed_password: str) -> bool:
    """Verify if the provided password matches the stored hash."""
    return pwd_context.verify(plain_password, hashed_password)

def create_access_token(data: dict, expires_delta: timedelta = None):
    """Generate JWT token with expiration."""
    to_encode = data.copy()
    expire = datetime.utcnow() + (expires_delta if expires_delta else timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES))
    to_encode.update({"exp": expire})
    
    return jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)

def decode_access_token(token: str):
    """Decode JWT token and verify its validity."""
    try:
        return jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
    except PyJWTError:
        return None
    except jwt.ExpiredSignature:
        return None

#####################################################################################33



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

# Password reset token handling
def generate_reset_token() -> str:
    """Generate a secure reset token."""
    return secrets.token_urlsafe(32)

def generate_reset_token_entry(user_id: int, db: Session) -> PasswordResetToken:
    """Generate and store a reset token in the database."""
    reset_token = generate_reset_token()
    expires_at = datetime.utcnow() + timedelta(hours=1)  # Token expires in 1 hour
    new_token = PasswordResetToken(user_id=user_id, token=reset_token, expires_at=expires_at)
    db.add(new_token)
    db.commit()
    return new_token

def send_reset_email(user_email: str, reset_link: str):
    """Send reset email with reset link."""
    send_email(user_email, "Password Reset Request", f"Click the link to reset your password: {reset_link}")

def validate_reset_token_entry(token: str, db: Session) -> PasswordResetToken:
    """Validate reset token's existence and expiration."""
    reset_token = db.query(PasswordResetToken).filter(PasswordResetToken.token == token).first()
    if not reset_token or reset_token.expires_at < datetime.utcnow():
        return None
    return reset_token

def verify_reset_token(token: str, db: Session) -> bool:
    """Verify the validity of the reset token."""
    reset_token = db.query(PasswordResetToken).filter(PasswordResetToken.token == token).first()
    if not reset_token or reset_token.expires_at < datetime.utcnow():
        return False
    return True