import type { Environment } from '../config/environments.js';
import { type ApiDeps } from '../http/client.js';
export interface EngineManifest {
    version: string;
    tarballUrl: string;
    sha256: string;
}
export declare function fetchEngineManifest(environment: Environment, accessToken: string, deps: ApiDeps): Promise<EngineManifest>;
export interface DownloadDeps {
    fetch: typeof globalThis.fetch;
}
/**
 * Downloads the tarball and verifies its digest before it is written. A signed URL is a
 * credential, so it never appears in an error message.
 */
export declare function downloadAndVerify(tarballUrl: string, expectedSha256: string, targetPath: string, deps: DownloadDeps): Promise<void>;
/**
 * The tarball stores three prefixes at different depths — game/src/<root>, game/agent-docs (plus
 * the sibling game/sw-cache-buster.js, which shares its strip depth) and templates — so it takes
 * three passes. A single pass cannot express them: `strip` is a fixed depth, and stripping 2 would
 * turn game/agent-docs/x.md into a bare x.md.
 *
 * Result: <engineDir>/{engine,types,bundle,debug,editor,genres}, <engineDir>/agent-docs,
 * <engineDir>/sw-cache-buster.js, and templates unpacked separately so the scaffolder can read
 * templates/index.json.
 *
 * `game/docs` is deliberately absent: those are engine-CONTRIBUTOR docs (how to edit the engine),
 * which is noise in a project where engine/ is read-only. Tarballs published before the corpus
 * moved still carry it, and the second pass simply does not match it — an old tarball produces a
 * project without agent-docs rather than a failure. See OPTIONAL_VENDORED_DIRS in project.ts.
 */
export declare function extractEngine(tarballPath: string, engineDir: string, templatesDir: string): Promise<void>;
/**
 * The line about engine drift, or null when there is nothing to say.
 *
 * A game is frozen against the engine it was last built with; the project it becomes vendors
 * whatever the manifest served it. Usually that is a handful of builds and nothing breaks, but the
 * CLI has no migration lane of its own — `bitmagic check` is where the difference shows up, so it
 * is worth naming the two versions before the creator sees a compile error and assumes the command
 * that just ran produced it.
 *
 * Shared by `import` (an export against the engine the Creator last edited it with) and `promote`
 * (a project against the engine ANOTHER environment serves, where the two genuinely differ most of
 * the time because prod's engine manifest lags dev's).
 */
export declare function engineDriftNotice(exported: string | null, vendored: string): string | null;