import json
import os

import pytest

# jsonschema is an optional dependency used for schema validation tests.
# Skip these tests if jsonschema is not installed in the current test environment.
jsonschema = pytest.importorskip("jsonschema", reason="jsonschema not available; skipping schema validation tests")
from jsonschema import validate, ValidationError


def load_json(path: str):
    with open(path, "r", encoding="utf-8") as f:
        return json.load(f)


def test_example_contract_validates_against_schema():
    schema = load_json(os.path.join(os.path.dirname(__file__), "..", "schemas", "safety_contract_schema.json"))
    example = load_json(os.path.join(os.path.dirname(__file__), "..", "examples", "contracts", "example_contract.json"))

    # Should not raise
    validate(instance=example, schema=schema)


def test_schema_rejects_additional_properties():
    schema = load_json(os.path.join(os.path.dirname(__file__), "..", "schemas", "safety_contract_schema.json"))
    example = load_json(os.path.join(os.path.dirname(__file__), "..", "examples", "contracts", "example_contract.json"))

    # Inject an unexpected property at top-level which is forbidden by additionalProperties=false
    example_with_extra = dict(example)
    example_with_extra["unexpected"] = "value"

    with pytest.raises(ValidationError):
        validate(instance=example_with_extra, schema=schema)