// file: kb-lib/tests/external_materializer_api.rs
// version: 1

//! Downstream-style compilation contract for externally implemented materializers.

const ACCEPTED_FAMILIES: &[kb_lib::EventFamily] = &[kb_lib::EventFamily::Audit];

struct ExternalAuditMaterializer;

impl kb_lib::EventMaterializer for ExternalAuditMaterializer {
    fn identity(&self) -> kb_lib::MaterializerIdentity {
        return kb_lib::MaterializerIdentity {
            name: "external_audit_materializer".to_string(),
            version: "1".to_string(),
        };
    }

    fn accepted_families(&self) -> &'static [kb_lib::EventFamily] {
        return ACCEPTED_FAMILIES;
    }

    fn transaction_policy(
        &self,
        _family: kb_lib::EventFamily,
    ) -> kb_lib::MaterializationTransactionPolicy {
        return kb_lib::MaterializationTransactionPolicy::SuccessfulOrFailedAudit;
    }

    fn materialize(
        &self,
        _observation: &kb_lib::DecodedObservation,
    ) -> kb_lib::MaterializerExecutionResult {
        return kb_lib::MaterializerExecutionResult::ignored();
    }
}

#[test]
fn external_materializer_uses_only_the_public_kb_lib_contract() {
    let materializer: &dyn kb_lib::EventMaterializer = &ExternalAuditMaterializer;
    assert_eq!(materializer.identity().name, "external_audit_materializer");
    assert_eq!(materializer.accepted_families(), ACCEPTED_FAMILIES);
}