import json
from mltrail_verifiable_provenance_ledger_for.ledger import Ledger


def test_contract_registry_entry_can_be_stored():
    ledger = Ledger()
    payload = {
        "registry_name": "GoC-Bridge-Registry",
        "primitives": [
            "Experiment",
            "Run",
            "Dataset",
            "Model",
            "Environment",
            "EvaluationMetric",
            "Policy",
        ],
        "version": "1.0",
    }
    block = ledger.add_record("ContractRegistryEntry", payload)

    # Basic sanity checks about the added block and its data
    assert block.index == 1
    assert block.data[0]["type"] == "ContractRegistryEntry"
    # Ensure the payload is preserved inside the contract record
    stored = block.data[0]
    assert stored["registry_name"] == payload["registry_name"]
    assert stored["primitives"] == payload["primitives"]


def test_delta_sync_basic():
    ledger_a = Ledger()
    ledger_b = Ledger()

    # Add a single registry entry in ledger_a
    ledger_a.add_record("ContractRegistryEntry", {"registry_name": "GoC", "version": "1.0"})

    # Use ledger_b's head hash as remote head to fetch delta from ledger_a
    delta = __import__("mltrail_verifiable_provenance_ledger_for.ledger", fromlist=["delta_sync"]).delta_sync(ledger_a, ledger_b.head_hash())
    # Should contain the single block from ledger_a (excluding genesis)
    assert isinstance(delta, list)
    assert len(delta) == 1
    assert delta[0]["index"] == 1