import json
from dataclasses import dataclass
from typing import List, Dict, Any, Optional


@dataclass
class SafetyContract:
    name: str
    pre: Optional[str]
    post: Optional[str]
    budgets: Dict[str, float]
    collision_rules: List[Dict[str, Any]]
    trust_policy: Dict[str, Any]


def parse_safety_contract_from_json(text: str) -> SafetyContract:
    data = json.loads(text)
    return SafetyContract(
        name=data.get("name", "contract"),
        pre=data.get("pre"),
        post=data.get("post"),
        budgets=data.get("budgets", {}),
        collision_rules=data.get("collision_rules", []),
        trust_policy=data.get("trust_policy", {}),
    )


def contract_to_minimal_dict(contract: SafetyContract) -> Dict[str, Any]:
    return {
        "name": contract.name,
        "pre": contract.pre,
        "post": contract.post,
        "budgets": contract.budgets,
        "collision_rules": contract.collision_rules,
        "trust_policy": contract.trust_policy,
    }