Find ALL Bugs in ONE Run

# Fixed with DevTraceTool findings (all 7 errors caught in ONE trace)
def process_payment(order_data):
    # FIX 1: KeyError prevention
    user_id = order_data.get('user_id')
    if not user_id:
        raise ValueError("user_id is required")

    # FIX 2 & 3: Type validation and coercion
    try:
        amount = float(order_data.get('amount', 0))
        discount_raw = order_data.get('discount', 0)
        # Handle both numeric and percentage discounts
        if isinstance(discount_raw, str) and '%' in discount_raw:
            discount = amount * (float(discount_raw.strip('%')) / 100)
        else:
            discount = float(discount_raw)
    except (ValueError, TypeError) as e:
        raise ValueError(f"Invalid amount or discount: {e}")

    # FIX 4 & 5: Null safety for payment method
    payment_method = order_data.get('payment_method')
    if not payment_method or not payment_method.get('stripe_token'):
        raise ValueError("Valid payment method required")

    token = payment_method['stripe_token']

    # FIX 6: Safe arithmetic
    final_amount = max(0, amount - discount)

    # FIX 7: Timeout and error handling
    try:
        response = stripe.charge(token, final_amount, timeout=30)
        if not response or 'transaction_id' not in response:
            raise ValueError("Invalid payment response")
        return response['transaction_id']
    except stripe.StripeError as e:
        logger.error(f"Payment failed: {e}")
        raise PaymentProcessingError(str(e))