use std::fs::{File, OpenOptions};
use std::io::Write;
use std::os::unix::fs::{MetadataExt, PermissionsExt};
use std::path::PathBuf;
use std::sync::atomic::{AtomicU64, Ordering};
use std::sync::{Arc, Mutex};
use std::thread::{self, JoinHandle};

use ed25519_dalek::SigningKey;
use lazaret_core::identity::{
    ClientId, ConfigurationFingerprint, CoordinatorId, DomainId, GenerationId, HostPath,
    NetworkSidecarId, SandboxId, SessionAnchorId, SessionId,
};
use lazaret_core::records::{
    ClientEnrollmentResponse, ControlRequest, ControlResponse, Domain, DurableDecision, Generation,
    GenerationIdentity, ProtocolVersion, Session, SessionBinding, SessionPhase,
    SessionRegistrationRequest, SessionRegistrationResponse, TlsCredential,
};
use lazaret_host_coordinator::control::{
    CONTROL_ALPN, ControlError, PendingClientEnrollment, PublishedControlFace, SessionRegistry,
    StagedControlFace, TrustAnchor,
};
use lazaret_host_coordinator::domain_store::{DomainStoreMutation, HostCoordinatorDomainStore};
use lazaret_host_coordinator::lifecycle::{
    DomainPhase, HostCoordinatorLifecycle, LifecycleAction, LifecycleAdapter,
};
use lazaret_linux::filesystem::try_exclusive_flock;
use rustix::process::getuid;
use x509_parser::extensions::GeneralName;
use x509_parser::parse_x509_certificate;

static NEXT_DIRECTORY: AtomicU64 = AtomicU64::new(0);

#[derive(Clone, Default)]
struct ControlLifecycleAdapter {
    publication: Arc<Mutex<Option<Arc<PublishedControlFace>>>>,
}

impl LifecycleAdapter for ControlLifecycleAdapter {
    type Error = ControlError;

    fn execute(
        &mut self,
        action: LifecycleAction,
        _generation: &Generation,
    ) -> Result<(), Self::Error> {
        if action == LifecycleAction::BeginTeardown {
            let mut publication = self.publication.lock().unwrap();
            if let Some(face) = publication.as_ref() {
                face.withdraw()?;
            }
            publication.take();
        }
        Ok(())
    }
}

struct TestDirectory(PathBuf);

impl TestDirectory {
    fn new(label: &str) -> Self {
        let sequence = NEXT_DIRECTORY.fetch_add(1, Ordering::Relaxed);
        let parent = PathBuf::from("/tmp");
        let path = parent.join(format!(
            "lazaret-control-{label}-{}-{sequence}",
            std::process::id()
        ));
        std::fs::create_dir(&path).unwrap();
        std::fs::set_permissions(&path, std::fs::Permissions::from_mode(0o700)).unwrap();
        Self(path)
    }

    fn path(&self, name: &str) -> PathBuf {
        self.0.join(name)
    }
}

impl Drop for TestDirectory {
    fn drop(&mut self) {
        std::fs::remove_dir_all(&self.0).unwrap();
    }
}

fn bytes(value: u8) -> [u8; 32] {
    [value; 32]
}

fn generation_identity(generation: u64) -> GenerationIdentity {
    GenerationIdentity {
        agent_profile: "trusted".into(),
        domain_id: DomainId::new(bytes(1)),
        generation_id: GenerationId::new(generation),
        configuration_fingerprint: ConfigurationFingerprint::new(bytes(2)),
        coordinator_id: CoordinatorId::new(bytes(u8::try_from(generation + 10).unwrap())),
        sandbox_id: SandboxId::new(bytes(u8::try_from(generation + 20).unwrap())),
    }
}

fn domain() -> Domain {
    Domain {
        domain_id: DomainId::new(bytes(1)),
        profile_name: "trusted".into(),
        canonical_workspace: HostPath::new(b"/workspace/project".to_vec()),
    }
}

fn generation(identity: &GenerationIdentity, decision: DurableDecision) -> Generation {
    Generation {
        domain_id: identity.domain_id,
        generation_id: identity.generation_id,
        configuration_fingerprint: identity.configuration_fingerprint,
        coordinator_id: identity.coordinator_id,
        network_sidecar_id: NetworkSidecarId::new(bytes(4)),
        sandbox_id: identity.sandbox_id,
        durable_decision: decision,
    }
}

fn open_store(
    directory: &TestDirectory,
    identity: &GenerationIdentity,
) -> Arc<HostCoordinatorDomainStore> {
    let lock_path = directory.path("domain.lock");
    let lock = OpenOptions::new()
        .read(true)
        .write(true)
        .create_new(true)
        .open(lock_path)
        .unwrap();
    let lock = try_exclusive_flock(lock).unwrap();
    let store = Arc::new(
        HostCoordinatorDomainStore::open(lock, &directory.path("domain.redb"), &domain()).unwrap(),
    );
    store
        .apply(&[DomainStoreMutation::PutGeneration(generation(
            identity,
            DurableDecision::None,
        ))])
        .unwrap();
    store
        .apply(&[DomainStoreMutation::PutGeneration(generation(
            identity,
            DurableDecision::Preparing,
        ))])
        .unwrap();
    store
        .apply(&[DomainStoreMutation::PutGeneration(generation(
            identity,
            DurableDecision::Published,
        ))])
        .unwrap();
    store
}

fn open_preparing_store(
    directory: &TestDirectory,
    identity: &GenerationIdentity,
) -> Arc<HostCoordinatorDomainStore> {
    let lock = OpenOptions::new()
        .read(true)
        .write(true)
        .create_new(true)
        .open(directory.path("domain.lock"))
        .unwrap();
    let store = Arc::new(
        HostCoordinatorDomainStore::open(
            try_exclusive_flock(lock).unwrap(),
            &directory.path("domain.redb"),
            &domain(),
        )
        .unwrap(),
    );
    for decision in [DurableDecision::None, DurableDecision::Preparing] {
        store
            .apply(&[DomainStoreMutation::PutGeneration(generation(
                identity, decision,
            ))])
            .unwrap();
    }
    store
}

fn open_empty_store(directory: &TestDirectory) -> Arc<HostCoordinatorDomainStore> {
    let lock = OpenOptions::new()
        .read(true)
        .write(true)
        .create_new(true)
        .open(directory.path("domain.lock"))
        .unwrap();
    Arc::new(
        HostCoordinatorDomainStore::open(
            try_exclusive_flock(lock).unwrap(),
            &directory.path("domain.redb"),
            &domain(),
        )
        .unwrap(),
    )
}

fn start_sandbox(
    lifecycle: &mut HostCoordinatorLifecycle<'_, ControlLifecycleAdapter, Arc<SessionRegistry>>,
    identity: &GenerationIdentity,
) {
    let owner = Session {
        generation_id: identity.generation_id,
        session_id: SessionId::new(bytes(80)),
        cli_id: ClientId::new(bytes(81)),
        session_anchor_id: SessionAnchorId::new(bytes(82)),
        session_phase: SessionPhase::New,
    };
    lifecycle
        .start_new_domain(generation(identity, DurableDecision::None), owner)
        .unwrap();
    lifecycle.create_trust_anchor().unwrap();
    lifecycle.start_runtime_supervisor().unwrap();
    lifecycle.lease_prepared_lower().unwrap();
    lifecycle.mount_state_anchor().unwrap();
    lifecycle.start_sidecar().unwrap();
    lifecycle.start_connectivity_helper().unwrap();
    lifecycle.mark_network_ready().unwrap();
    lifecycle.arm_runtime_causal_edge().unwrap();
    lifecycle.start_sandbox().unwrap();
}

fn publish(
    directory: &TestDirectory,
    identity: &GenerationIdentity,
) -> (Arc<PublishedControlFace>, Arc<HostCoordinatorDomainStore>) {
    let store = open_store(directory, identity);
    let face = PublishedControlFace::publish(
        &directory.0,
        getuid().as_raw(),
        TrustAnchor::create(identity.clone()).unwrap(),
        Arc::clone(&store),
    )
    .unwrap();
    (Arc::new(face), store)
}

fn server(face: &Arc<PublishedControlFace>) -> JoinHandle<Result<(), ControlError>> {
    let face = Arc::clone(face);
    thread::spawn(move || face.serve_next())
}

struct EnrolledClient {
    pending: PendingClientEnrollment,
    credential: TlsCredential,
    server_certificate: Vec<u8>,
}

fn enroll(face: &Arc<PublishedControlFace>, cli_id: ClientId) -> EnrolledClient {
    let pending = PendingClientEnrollment::create(
        face.publication_identity().generation_identity.clone(),
        cli_id,
    )
    .unwrap();
    let serving = server(face);
    let config = PublishedControlFace::client_config(face.publication_identity(), None).unwrap();
    let mut stream =
        PublishedControlFace::connect(face.socket_path(), config, face.publication_identity())
            .unwrap();
    PublishedControlFace::send(
        &mut stream,
        &ControlRequest::Enroll(pending.request().clone()),
    )
    .unwrap();
    let response: ControlResponse = PublishedControlFace::receive(&mut stream).unwrap();
    assert_eq!(
        stream.conn.protocol_version(),
        Some(rustls::ProtocolVersion::TLSv1_3)
    );
    assert_eq!(stream.conn.alpn_protocol(), Some(CONTROL_ALPN));
    let server_certificate = stream.conn.peer_certificates().unwrap()[0].to_vec();
    drop(stream);
    serving.join().unwrap().unwrap();
    let ControlResponse::Enrolled(ClientEnrollmentResponse { credential, .. }) = response else {
        panic!("unexpected enrollment response")
    };
    EnrolledClient {
        pending,
        credential,
        server_certificate,
    }
}

fn assert_certificate_profiles(face: &PublishedControlFace, client: &EnrolledClient) {
    let (_, ca) =
        parse_x509_certificate(&face.publication_identity().tls_ca_certificate_der).unwrap();
    assert!(ca.is_ca());
    assert!(ca.key_usage().unwrap().unwrap().value.key_cert_sign());
    assert_eq!(
        ca.signature_algorithm.algorithm.to_id_string(),
        "1.3.101.112"
    );

    let (_, server_certificate) = parse_x509_certificate(&client.server_certificate).unwrap();
    let server_usage = server_certificate.extended_key_usage().unwrap().unwrap();
    assert!(server_usage.value.server_auth);
    assert!(!server_usage.value.client_auth);
    let server_names = server_certificate
        .subject_alternative_name()
        .unwrap()
        .unwrap();
    assert!(
        server_names
            .value
            .general_names
            .iter()
            .any(|name| { matches!(name, GeneralName::DNSName("coordinator.lazaret.invalid")) })
    );
    assert!(
        server_certificate.validity().not_after.timestamp()
            - server_certificate.validity().not_before.timestamp()
            <= 3_660
    );

    let (_, client_certificate) =
        parse_x509_certificate(&client.credential.certificate_der).unwrap();
    let client_usage = client_certificate.extended_key_usage().unwrap().unwrap();
    assert!(client_usage.value.client_auth);
    assert!(!client_usage.value.server_auth);
    assert_eq!(
        client_certificate
            .signature_algorithm
            .algorithm
            .to_id_string(),
        "1.3.101.112"
    );
    assert!(
        client_certificate.validity().not_after.timestamp()
            - client_certificate.validity().not_before.timestamp()
            <= 3_660
    );
}

fn registration_binding(
    identity: &GenerationIdentity,
    cli_id: ClientId,
    session: u8,
    anchor: u8,
) -> SessionBinding {
    SessionBinding {
        generation_identity: identity.clone(),
        cli_id,
        session_id: SessionId::new(bytes(session)),
        session_anchor_public_key: SigningKey::from_bytes(&bytes(anchor))
            .verifying_key()
            .to_bytes()
            .to_vec(),
    }
}

fn open_registration(
    face: &Arc<PublishedControlFace>,
    client: &EnrolledClient,
    binding: SessionBinding,
) -> (
    rustls::StreamOwned<rustls::ClientConnection, std::os::unix::net::UnixStream>,
    JoinHandle<Result<(), ControlError>>,
    SessionRegistrationResponse,
) {
    let serving = server(face);
    let config = PublishedControlFace::client_config(
        face.publication_identity(),
        Some((&client.credential, client.pending.private_key())),
    )
    .unwrap();
    let mut stream =
        PublishedControlFace::connect(face.socket_path(), config, face.publication_identity())
            .unwrap();
    PublishedControlFace::send(
        &mut stream,
        &ControlRequest::Register(SessionRegistrationRequest {
            protocol_version: ProtocolVersion::V1,
            session_binding: binding,
        }),
    )
    .unwrap();
    let response: ControlResponse = PublishedControlFace::receive(&mut stream).unwrap();
    let ControlResponse::Registered(response) = response else {
        panic!("unexpected registration response")
    };
    (stream, serving, response)
}

fn refused_registration(
    face: &Arc<PublishedControlFace>,
    client: &EnrolledClient,
    binding: SessionBinding,
) -> ControlError {
    let serving = server(face);
    let config = PublishedControlFace::client_config(
        face.publication_identity(),
        Some((&client.credential, client.pending.private_key())),
    )
    .unwrap();
    let mut stream =
        PublishedControlFace::connect(face.socket_path(), config, face.publication_identity())
            .unwrap();
    PublishedControlFace::send(
        &mut stream,
        &ControlRequest::Register(SessionRegistrationRequest {
            protocol_version: ProtocolVersion::V1,
            session_binding: binding,
        }),
    )
    .unwrap();
    assert!(PublishedControlFace::receive::<ControlResponse>(&mut stream).is_err());
    drop(stream);
    serving.join().unwrap().unwrap_err()
}

#[test]
fn real_uds_tls_enrollment_and_registration_preserve_exact_profiles_and_session_state() {
    let directory = TestDirectory::new("complete");
    let identity = generation_identity(7);
    let (face, store) = publish(&directory, &identity);

    let socket_metadata = std::fs::symlink_metadata(face.socket_path()).unwrap();
    let identity_metadata = std::fs::symlink_metadata(face.identity_path()).unwrap();
    assert_eq!(socket_metadata.uid(), getuid().as_raw());
    assert_eq!(socket_metadata.mode() & 0o7777, 0o600);
    assert_eq!(identity_metadata.uid(), getuid().as_raw());
    assert_eq!(identity_metadata.mode() & 0o7777, 0o600);
    assert_eq!(face.socket_path().file_name().unwrap(), "c.sock");
    assert_eq!(
        face.identity_path().file_name().unwrap(),
        "protocol-identity.postcard"
    );

    let client = enroll(&face, ClientId::new(bytes(30)));
    assert_certificate_profiles(&face, &client);

    let mut wrong_leaf_pin = face.publication_identity().clone();
    wrong_leaf_pin.coordinator_tls_certificate_sha256 =
        lazaret_core::identity::CertificateDigest::new(bytes(99));
    let serving = server(&face);
    let config = PublishedControlFace::client_config(face.publication_identity(), None).unwrap();
    assert!(PublishedControlFace::connect(face.socket_path(), config, &wrong_leaf_pin).is_err());
    assert!(serving.join().unwrap().is_err());

    let serving = server(&face);
    let config = PublishedControlFace::client_config(
        face.publication_identity(),
        Some((&client.credential, client.pending.private_key())),
    )
    .unwrap();
    let mut stream =
        PublishedControlFace::connect(face.socket_path(), config, face.publication_identity())
            .unwrap();
    PublishedControlFace::send(
        &mut stream,
        &ControlRequest::Enroll(client.pending.request().clone()),
    )
    .unwrap();
    assert!(PublishedControlFace::receive::<ControlResponse>(&mut stream).is_err());
    drop(stream);
    assert!(matches!(
        serving.join().unwrap().unwrap_err(),
        ControlError::InvalidRequest
    ));

    let binding = registration_binding(&identity, ClientId::new(bytes(30)), 31, 32);
    let (stream, serving, response) = open_registration(&face, &client, binding.clone());
    assert_eq!(response.session_capability.session_binding, binding);
    assert_eq!(face.registry().connected_sessions().unwrap().len(), 1);
    assert_eq!(
        store.snapshot().unwrap().sessions[0].session_phase,
        SessionPhase::Attached
    );
    drop(stream);
    serving.join().unwrap().unwrap();
    assert!(face.registry().connected_sessions().unwrap().is_empty());
    assert_eq!(
        store.snapshot().unwrap().sessions[0].session_phase,
        SessionPhase::Closed
    );
}

#[test]
fn duplicate_session_cli_and_anchor_identities_are_refused_while_registered() {
    let directory = TestDirectory::new("duplicates");
    let identity = generation_identity(7);
    let (face, _) = publish(&directory, &identity);
    let first = enroll(&face, ClientId::new(bytes(40)));
    let second = enroll(&face, ClientId::new(bytes(41)));
    let mismatched_cli = registration_binding(&identity, ClientId::new(bytes(41)), 39, 40);
    assert!(matches!(
        refused_registration(&face, &first, mismatched_cli),
        ControlError::InvalidCertificateProfile
    ));
    let first_binding = registration_binding(&identity, ClientId::new(bytes(40)), 42, 43);
    let (first_stream, first_server, _) = open_registration(&face, &first, first_binding.clone());

    let duplicate_session = registration_binding(&identity, ClientId::new(bytes(41)), 42, 44);
    assert!(matches!(
        refused_registration(&face, &second, duplicate_session),
        ControlError::DuplicateIdentity
    ));
    let duplicate_cli = registration_binding(&identity, ClientId::new(bytes(40)), 45, 46);
    assert!(matches!(
        refused_registration(&face, &first, duplicate_cli),
        ControlError::DuplicateIdentity
    ));
    let duplicate_anchor = SessionBinding {
        generation_identity: identity,
        cli_id: ClientId::new(bytes(41)),
        session_id: SessionId::new(bytes(47)),
        session_anchor_public_key: first_binding.session_anchor_public_key,
    };
    assert!(matches!(
        refused_registration(&face, &second, duplicate_anchor),
        ControlError::DuplicateIdentity
    ));

    drop(first_stream);
    first_server.join().unwrap().unwrap();
}

#[test]
fn concurrent_connections_validate_publication_without_shared_file_offsets() {
    let directory = TestDirectory::new("concurrent-publication");
    let identity = generation_identity(7);
    let (face, _store) = publish(&directory, &identity);
    let clients = (40..56)
        .map(|value| {
            let face = Arc::clone(&face);
            thread::spawn(move || enroll(&face, ClientId::new(bytes(value))))
        })
        .collect::<Vec<_>>();
    for client in clients {
        client.join().unwrap();
    }
}

#[test]
fn anonymous_connections_are_enrollment_only_bounded_and_exact_alpn_is_required() {
    let directory = TestDirectory::new("anonymous");
    let identity = generation_identity(7);
    let (face, _) = publish(&directory, &identity);

    let serving = server(&face);
    let config = PublishedControlFace::client_config(face.publication_identity(), None).unwrap();
    let mut stream =
        PublishedControlFace::connect(face.socket_path(), config, face.publication_identity())
            .unwrap();
    PublishedControlFace::send(
        &mut stream,
        &ControlRequest::Register(SessionRegistrationRequest {
            protocol_version: ProtocolVersion::V1,
            session_binding: registration_binding(&identity, ClientId::new(bytes(48)), 49, 50),
        }),
    )
    .unwrap();
    assert!(PublishedControlFace::receive::<ControlResponse>(&mut stream).is_err());
    drop(stream);
    assert!(matches!(
        serving.join().unwrap().unwrap_err(),
        ControlError::InvalidRequest
    ));

    let serving = server(&face);
    let config = PublishedControlFace::client_config(face.publication_identity(), None).unwrap();
    let mut stream =
        PublishedControlFace::connect(face.socket_path(), config, face.publication_identity())
            .unwrap();
    stream.write_all(&8_193_u32.to_be_bytes()).unwrap();
    assert!(PublishedControlFace::receive::<ControlResponse>(&mut stream).is_err());
    drop(stream);
    assert!(matches!(
        serving.join().unwrap().unwrap_err(),
        ControlError::OversizeRequest {
            length: 8_193,
            maximum: 8_192
        }
    ));

    let mut tampered = PendingClientEnrollment::create(identity.clone(), ClientId::new(bytes(51)))
        .unwrap()
        .request()
        .clone();
    *tampered.certificate_signing_request_der.last_mut().unwrap() ^= 1;
    let serving = server(&face);
    let config = PublishedControlFace::client_config(face.publication_identity(), None).unwrap();
    let mut stream =
        PublishedControlFace::connect(face.socket_path(), config, face.publication_identity())
            .unwrap();
    PublishedControlFace::send(&mut stream, &ControlRequest::Enroll(tampered)).unwrap();
    assert!(PublishedControlFace::receive::<ControlResponse>(&mut stream).is_err());
    drop(stream);
    assert!(matches!(
        serving.join().unwrap().unwrap_err(),
        ControlError::Certificate(_)
    ));

    let serving = server(&face);
    let mut config =
        PublishedControlFace::client_config(face.publication_identity(), None).unwrap();
    config.alpn_protocols = vec![b"not-lazaret".to_vec()];
    assert!(
        PublishedControlFace::connect(face.socket_path(), config, face.publication_identity(),)
            .is_err()
    );
    assert!(serving.join().unwrap().is_err());
}

#[test]
fn stale_generation_and_publication_identity_are_refused() {
    let directory = TestDirectory::new("stale");
    let identity = generation_identity(7);
    let (face, store) = publish(&directory, &identity);

    let stale =
        PendingClientEnrollment::create(generation_identity(6), ClientId::new(bytes(60))).unwrap();
    let serving = server(&face);
    let config = PublishedControlFace::client_config(face.publication_identity(), None).unwrap();
    let mut stream =
        PublishedControlFace::connect(face.socket_path(), config, face.publication_identity())
            .unwrap();
    PublishedControlFace::send(
        &mut stream,
        &ControlRequest::Enroll(stale.request().clone()),
    )
    .unwrap();
    assert!(PublishedControlFace::receive::<ControlResponse>(&mut stream).is_err());
    drop(stream);
    assert!(matches!(
        serving.join().unwrap().unwrap_err(),
        ControlError::StaleGeneration
    ));

    let later = generation_identity(8);
    for decision in [
        DurableDecision::None,
        DurableDecision::Preparing,
        DurableDecision::Published,
    ] {
        store
            .apply(&[DomainStoreMutation::PutGeneration(generation(
                &later, decision,
            ))])
            .unwrap();
    }
    let serving = server(&face);
    let config = PublishedControlFace::client_config(face.publication_identity(), None).unwrap();
    assert!(
        PublishedControlFace::connect(face.socket_path(), config, face.publication_identity(),)
            .is_err()
    );
    assert!(matches!(
        serving.join().unwrap().unwrap_err(),
        ControlError::StaleGeneration
    ));
}

#[test]
fn host_coordinator_key_loss_never_reuses_old_tls_authority() {
    let directory = TestDirectory::new("key-loss");
    let identity = generation_identity(7);
    let store = open_store(&directory, &identity);
    let old_face = Arc::new(
        PublishedControlFace::publish(
            &directory.0,
            getuid().as_raw(),
            TrustAnchor::create(identity.clone()).unwrap(),
            Arc::clone(&store),
        )
        .unwrap(),
    );
    let old_client = enroll(&old_face, ClientId::new(bytes(70)));
    let old_publication = old_face.publication_identity().clone();
    drop(old_face);

    let new_face = Arc::new(
        PublishedControlFace::publish(
            &directory.0,
            getuid().as_raw(),
            TrustAnchor::create(identity).unwrap(),
            store,
        )
        .unwrap(),
    );
    assert_ne!(
        new_face.publication_identity().tls_ca_certificate_der,
        old_publication.tls_ca_certificate_der
    );
    let serving = server(&new_face);
    let old_config = PublishedControlFace::client_config(
        &old_publication,
        Some((&old_client.credential, old_client.pending.private_key())),
    )
    .unwrap();
    assert!(
        PublishedControlFace::connect(new_face.socket_path(), old_config, &old_publication,)
            .is_err()
    );
    assert!(serving.join().unwrap().is_err());
}

#[test]
fn publication_refuses_wrong_root_path_mode_and_stale_identity_file() {
    let mode_directory = TestDirectory::new("mode");
    std::fs::set_permissions(&mode_directory.0, std::fs::Permissions::from_mode(0o755)).unwrap();
    let identity = generation_identity(7);
    let store = open_store(&mode_directory, &identity);
    assert!(matches!(
        PublishedControlFace::publish(
            &mode_directory.0,
            getuid().as_raw(),
            TrustAnchor::create(identity.clone()).unwrap(),
            store,
        ),
        Err(ControlError::InvalidPath(_))
    ));

    let symlink_parent = TestDirectory::new("symlink-parent");
    let target = symlink_parent.path("target");
    std::fs::create_dir(&target).unwrap();
    std::fs::set_permissions(&target, std::fs::Permissions::from_mode(0o700)).unwrap();
    let link = symlink_parent.path("link");
    std::os::unix::fs::symlink(&target, &link).unwrap();
    let store_directory = TestDirectory::new("symlink-store");
    let store = open_store(&store_directory, &identity);
    assert!(matches!(
        PublishedControlFace::publish(
            &link,
            getuid().as_raw(),
            TrustAnchor::create(identity.clone()).unwrap(),
            store,
        ),
        Err(ControlError::InvalidPath(_))
    ));

    let stale_directory = TestDirectory::new("stale-file");
    let (face, _) = publish(&stale_directory, &identity);
    let mut identity_file = OpenOptions::new()
        .write(true)
        .truncate(true)
        .open(face.identity_path())
        .unwrap();
    identity_file.write_all(b"stale publication").unwrap();
    identity_file.sync_all().unwrap();
    let serving = server(&face);
    let config = PublishedControlFace::client_config(face.publication_identity(), None).unwrap();
    assert!(
        PublishedControlFace::connect(face.socket_path(), config, face.publication_identity(),)
            .is_err()
    );
    assert!(matches!(
        serving.join().unwrap().unwrap_err(),
        ControlError::InvalidPublication(_)
    ));
}

#[test]
fn publication_refuses_preexisting_fixed_control_path() {
    let directory = TestDirectory::new("existing");
    let identity = generation_identity(7);
    let store = open_store(&directory, &identity);
    File::create(directory.path("c.sock")).unwrap();
    assert!(matches!(
        PublishedControlFace::publish(
            &directory.0,
            getuid().as_raw(),
            TrustAnchor::create(identity).unwrap(),
            store,
        ),
        Err(ControlError::InvalidPublication(_))
    ));
}

#[test]
fn prepared_control_face_admits_only_after_generation_publication() {
    let directory = TestDirectory::new("publication-gate");
    let identity = generation_identity(7);
    let store = open_preparing_store(&directory, &identity);
    let registry = Arc::new(SessionRegistry::new(Arc::clone(&store), identity.clone()));
    let staged = StagedControlFace::stage(
        &directory.0,
        getuid().as_raw(),
        TrustAnchor::create(identity.clone()).unwrap(),
        registry,
    )
    .unwrap();
    assert!(std::os::unix::net::UnixStream::connect(directory.path("c.sock")).is_err());

    store
        .apply(&[DomainStoreMutation::PutGeneration(generation(
            &identity,
            DurableDecision::Published,
        ))])
        .unwrap();
    let face = Arc::new(staged.expose().unwrap());
    let client = enroll(&face, ClientId::new(bytes(90)));
    assert_eq!(client.credential.generation_identity, identity);
}

#[test]
fn coordinated_control_session_tracks_lifecycle_and_withdraws_before_teardown() {
    let directory = TestDirectory::new("coordinated-lifecycle");
    let identity = generation_identity(7);
    let store = open_empty_store(&directory);
    let registry = Arc::new(SessionRegistry::new(Arc::clone(&store), identity.clone()));
    let adapter = ControlLifecycleAdapter::default();
    let publication_slot = Arc::clone(&adapter.publication);
    let mut lifecycle = HostCoordinatorLifecycle::new(&store, adapter, Arc::clone(&registry));
    start_sandbox(&mut lifecycle, &identity);
    let staged = StagedControlFace::stage(
        &directory.0,
        getuid().as_raw(),
        TrustAnchor::create(identity.clone()).unwrap(),
        Arc::clone(&registry),
    )
    .unwrap();
    lifecycle.publish_domain().unwrap();
    lifecycle
        .disconnect_session(SessionId::new(bytes(80)))
        .unwrap();
    let face = Arc::new(staged.expose().unwrap());
    *publication_slot.lock().unwrap() = Some(Arc::clone(&face));
    let client = enroll(&face, ClientId::new(bytes(90)));
    let binding = registration_binding(&identity, ClientId::new(bytes(90)), 91, 92);
    let session_id = binding.session_id;
    let lifecycle = Arc::new(Mutex::new(lifecycle));

    thread::scope(|scope| {
        let serving_face = Arc::clone(&face);
        let serving_lifecycle = Arc::clone(&lifecycle);
        let serving = scope.spawn(move || {
            serving_face.serve_next_coordinated(
                |admission| {
                    serving_lifecycle
                        .lock()
                        .unwrap()
                        .admit_session(admission)
                        .map_err(|error| ControlError::Lifecycle(error.to_string()))
                },
                |session_id| {
                    serving_lifecycle
                        .lock()
                        .unwrap()
                        .disconnect_session(session_id)
                        .map_err(|error| ControlError::Lifecycle(error.to_string()))
                },
            )
        });
        let config = PublishedControlFace::client_config(
            face.publication_identity(),
            Some((&client.credential, client.pending.private_key())),
        )
        .unwrap();
        let mut stream =
            PublishedControlFace::connect(face.socket_path(), config, face.publication_identity())
                .unwrap();
        PublishedControlFace::send(
            &mut stream,
            &ControlRequest::Register(SessionRegistrationRequest {
                protocol_version: ProtocolVersion::V1,
                session_binding: binding,
            }),
        )
        .unwrap();
        let _: ControlResponse = PublishedControlFace::receive(&mut stream).unwrap();
        {
            let lifecycle = lifecycle.lock().unwrap();
            assert_eq!(
                lifecycle.session_phase(session_id),
                Some(SessionPhase::Attached)
            );
            assert_eq!(lifecycle.registered_sessions(), 1);
            assert!(!lifecycle.is_teardown_ready());
        }
        drop(stream);
        serving.join().unwrap().unwrap();
    });

    let mut lifecycle = lifecycle.lock().unwrap();
    assert_eq!(
        lifecycle.session_phase(session_id),
        Some(SessionPhase::Closed)
    );
    assert!(lifecycle.is_teardown_ready());
    std::fs::set_permissions(&directory.0, std::fs::Permissions::from_mode(0o500)).unwrap();
    assert!(lifecycle.begin_teardown().is_err());
    assert_eq!(lifecycle.phase(), DomainPhase::Ready);
    assert!(lifecycle.is_published());
    assert!(face.socket_path().exists());
    assert!(face.identity_path().exists());
    std::fs::set_permissions(&directory.0, std::fs::Permissions::from_mode(0o700)).unwrap();
    lifecycle.begin_teardown().unwrap();
    assert_eq!(lifecycle.phase(), DomainPhase::Stopping);
    assert!(!lifecycle.is_published());
    assert!(!face.socket_path().exists());
    assert!(!face.identity_path().exists());
    assert!(std::os::unix::net::UnixStream::connect(face.socket_path()).is_err());
}