import math
import random


class PrivacyBudget:
    def __init__(self, total_budget: float = 1.0):
        self.total_budget = total_budget
        self.used = 0.0

    def spend(self, amount: float) -> bool:
        if self.used + amount > self.total_budget + 1e-9:
            return False
        self.used += amount
        return True

    def remaining(self) -> float:
        return max(self.total_budget - self.used, 0.0)


def laplace_noise(scale: float) -> float:
    # Simple Laplace noise for DP; symmetric around 0
    u = random.random() - 0.5
    return -scale * math.copysign(1.0, u) * math.log(1.0 - 2.0 * abs(u))