#[test]
fn semantic_corpus_preserves_supported_changesets_and_read_only_lower_use() {
    let fixture = Fixture::new();
    let first = layer(&lower_entries());
    let second = layer(&upper_entries());
    let request = fixture.request(
        1,
        &[
            (compress(&first, OCI_GZIP), OCI_GZIP),
            (compress(&second, OCI_ZSTD), OCI_ZSTD),
        ],
    );
    let artifact = fixture.store.prepare(&request).unwrap();
    let root = fixture.artifact_root(&artifact);
    assert!(!root.join("gone").exists());
    assert!(!root.join("opaque/old").exists());
    assert_eq!(std::fs::read(root.join("opaque/new")).unwrap(), b"new");
    assert_eq!(
        std::fs::read(root.join("directory-to-file")).unwrap(),
        b"replacement"
    );
    assert_eq!(
        std::fs::read(root.join("file-to-directory/new")).unwrap(),
        b"new"
    );
    assert_eq!(
        std::fs::read_link(root.join("symbolic")).unwrap(),
        Path::new("target")
    );
    assert_eq!(
        std::fs::metadata(root.join("hard")).unwrap().ino(),
        std::fs::metadata(root.join("target")).unwrap().ino()
    );
    assert_eq!(std::fs::read(root.join("forward")).unwrap(), b"forward");
    assert_eq!(
        std::fs::metadata(root.join("later"))
            .unwrap()
            .permissions()
            .mode()
            & 0o7777,
        0o4755
    );

    std::fs::remove_dir_all(&request.layout_path).unwrap();
    let mut lower = File::open(root.join("directory-to-file")).unwrap();
    let mut bytes = Vec::new();
    lower.read_to_end(&mut bytes).unwrap();
    assert_eq!(bytes, b"replacement");
    assert!(
        fixture
            .root
            .join("stages")
            .read_dir()
            .unwrap()
            .next()
            .is_none()
    );
}
#[test]
fn request_manifest_identity_must_match_verified_layout_manifest() {
    let fixture = Fixture::new();
    let bytes = layer(&[Entry {
        path: "payload",
        kind: EntryType::Regular,
        data: b"content",
        target: None,
        mode: 0o644,
    }]);
    let mut request = fixture.request(3, &[(bytes, OCI_TAR)]);
    request.selected_manifest_digest = [0xff; 32];

    assert!(matches!(
        fixture.store.prepare(&request),
        Err(PreparedLowerError::ManifestSelection { .. })
    ));
    let snapshot = fixture.catalog.snapshot().unwrap();
    assert!(snapshot.prepared_artifacts.is_empty());
    assert!(snapshot.prepare_operations.is_empty());
}

#[test]
fn layer_entry_matching_internal_spool_name_is_preserved() {
    let fixture = Fixture::new();
    let bytes = layer(&[Entry {
        path: ".layer-0.tar",
        kind: EntryType::Regular,
        data: b"image-owned",
        target: None,
        mode: 0o640,
    }]);
    let request = fixture.request(4, &[(bytes, OCI_TAR)]);

    let artifact = fixture.store.prepare(&request).unwrap();
    assert_eq!(
        std::fs::read(fixture.artifact_root(&artifact).join(".layer-0.tar")).unwrap(),
        b"image-owned"
    );
}

#[test]
fn root_directory_layer_entry_is_applied() {
    let fixture = Fixture::new();
    let bytes = layer(&[
        Entry {
            path: ".",
            kind: EntryType::Directory,
            data: b"",
            target: None,
            mode: 0o755,
        },
        Entry {
            path: "payload",
            kind: EntryType::Regular,
            data: b"content",
            target: None,
            mode: 0o644,
        },
    ]);
    let request = fixture.request(5, &[(bytes, OCI_TAR)]);

    let artifact = fixture.store.prepare(&request).unwrap();
    let root = fixture.artifact_root(&artifact);
    assert_eq!(std::fs::read(root.join("payload")).unwrap(), b"content");
    assert_eq!(
        root.metadata().unwrap().permissions().mode() & 0o7777,
        0o755
    );
}

#[test]
fn container_root_owner_maps_to_invoking_host_ids() {
    let fixture = Fixture::new();
    let bytes = layer_with_owner(
        &[Entry {
            path: "payload",
            kind: EntryType::Regular,
            data: b"content",
            target: None,
            mode: 0o640,
        }],
        0,
        0,
    );
    let mut request = fixture.request(6, &[(bytes, OCI_TAR)]);
    request.id_map = IdMap {
        uid: vec![IdMapRange {
            container_id: 0,
            namespace_id: rustix::process::geteuid().as_raw(),
            size: 1,
        }],
        gid: vec![IdMapRange {
            container_id: 0,
            namespace_id: rustix::process::getegid().as_raw(),
            size: 1,
        }],
    };

    let artifact = fixture.store.prepare(&request).unwrap();
    let metadata = fixture
        .artifact_root(&artifact)
        .join("payload")
        .metadata()
        .unwrap();
    assert_eq!(metadata.uid(), rustix::process::geteuid().as_raw());
    assert_eq!(metadata.gid(), rustix::process::getegid().as_raw());
}

#[test]
fn unmapped_nonzero_owners_refuse_before_publication() {
    for (operation, uid, gid) in [(7, 1, 0), (8, 0, 1)] {
        let fixture = Fixture::new();
        let bytes = layer_with_owner(
            &[Entry {
                path: "payload",
                kind: EntryType::Regular,
                data: b"content",
                target: None,
                mode: 0o640,
            }],
            uid,
            gid,
        );
        let mut request = fixture.request(operation, &[(bytes, OCI_TAR)]);
        request.id_map = IdMap {
            uid: vec![IdMapRange {
                container_id: 0,
                namespace_id: rustix::process::geteuid().as_raw(),
                size: 1,
            }],
            gid: vec![IdMapRange {
                container_id: 0,
                namespace_id: rustix::process::getegid().as_raw(),
                size: 1,
            }],
        };

        assert!(matches!(
            fixture.store.prepare(&request),
            Err(PreparedLowerError::Materialization { .. })
        ));
        assert!(
            fixture
                .catalog
                .snapshot()
                .unwrap()
                .prepared_artifacts
                .is_empty()
        );
    }
}

#[test]
fn root_opaque_whiteout_removes_only_lower_layer_entries() {
    let fixture = Fixture::new();
    let lower = layer(&[Entry {
        path: "old",
        kind: EntryType::Regular,
        data: b"old",
        target: None,
        mode: 0o644,
    }]);
    let upper = layer(&[
        Entry {
            path: "new",
            kind: EntryType::Regular,
            data: b"new",
            target: None,
            mode: 0o644,
        },
        Entry {
            path: ".wh..wh..opq",
            kind: EntryType::Regular,
            data: b"",
            target: None,
            mode: 0o000,
        },
    ]);
    let request = fixture.request(2, &[(lower, OCI_TAR), (upper, OCI_TAR)]);
    let artifact = fixture.store.prepare(&request).unwrap();
    let root = fixture.artifact_root(&artifact);
    assert!(!root.join("old").exists());
    assert_eq!(std::fs::read(root.join("new")).unwrap(), b"new");
}

#[test]
fn hostile_and_corrupt_layers_refuse_without_publication() {
    let cases = [
        layer(&[Entry {
            path: "pipe",
            kind: EntryType::Fifo,
            data: b"",
            target: None,
            mode: 0o644,
        }]),
        layer(&[Entry {
            path: "escape",
            kind: EntryType::Link,
            data: b"",
            target: Some("../outside"),
            mode: 0o644,
        }]),
        xattr_layer(),
    ];
    for (index, bytes) in cases.into_iter().enumerate() {
        let fixture = Fixture::new();
        let request = fixture.request(u8::try_from(index).unwrap() + 10, &[(bytes, OCI_TAR)]);
        assert!(matches!(
            fixture.store.prepare(&request),
            Err(PreparedLowerError::Materialization { .. })
        ));
        let snapshot = fixture.catalog.snapshot().unwrap();
        assert!(snapshot.prepared_artifacts.is_empty());
        assert!(snapshot.prepare_operations.is_empty());
        assert!(
            fixture
                .root
                .join("stages")
                .read_dir()
                .unwrap()
                .next()
                .is_none()
        );
    }

    let fixture = Fixture::new();
    let bytes = layer(&[Entry {
        path: "file",
        kind: EntryType::Regular,
        data: b"content",
        target: None,
        mode: 0o644,
    }]);
    let request = fixture.request(20, &[(bytes, OCI_TAR)]);
    let blob = request
        .layout_path
        .join("blobs/sha256")
        .read_dir()
        .unwrap()
        .map(|entry| entry.unwrap().path())
        .find(|path| std::fs::metadata(path).unwrap().len() > 1024)
        .unwrap();
    OpenOptionsExt::append_byte(&blob);
    assert!(matches!(
        fixture.store.prepare(&request),
        Err(PreparedLowerError::LayerValidation { .. })
    ));
    assert!(
        fixture
            .catalog
            .snapshot()
            .unwrap()
            .prepared_artifacts
            .is_empty()
    );
}

struct OpenOptionsExt;

impl OpenOptionsExt {
    fn append_byte(path: &Path) {
        let mut file = std::fs::OpenOptions::new().append(true).open(path).unwrap();
        file.write_all(b"x").unwrap();
    }
}