from nebulaforge.contracts import LocalProblem, SharedVariables, PlanDelta, AuditLog
import json

def test_contract_dataclasses():
    lp = LocalProblem(id="lp1", domain="rover", description="test", version=1)
    sv = SharedVariables(variables={"a": 1}, version=1)
    pd = PlanDelta(delta={"x": 1}, timestamp=123.456, version=1)
    al = AuditLog(entry="update", signer="tester", timestamp=123.456, contract_id="lp1", version=1)

    assert isinstance(lp, LocalProblem)
    assert lp.id == "lp1"
    assert isinstance(sv.variables, dict)
    assert isinstance(pd.delta, dict)
    assert isinstance(al.entry, str)

    # JSON serialization sanity check
    from nebulaforge.contracts import to_json
    json_str = to_json(lp)
    assert isinstance(json_str, str)
    data = json.loads(json_str)
    assert data["id"] == "lp1"