import { SyncEngine, SyncHandle, SyncRegistration } from '../../sync/types';
import { ChromeStorageAdapter, ChromeStorageAdapterOptions } from './chromeStorageAdapter';
export type ChromeExtensionSyncEngineOptions = ChromeStorageAdapterOptions | {
    storage: ChromeStorageAdapter;
};
export declare class ChromeExtensionSyncEngine implements SyncEngine {
    readonly injectStorageMetadata = true;
    readonly sessionId: string;
    private readonly area;
    private readonly storageKeyPrefix;
    private readonly registrations;
    private isListening;
    constructor(options?: ChromeExtensionSyncEngineOptions);
    destroy(): void;
    register<T extends Record<string, unknown>>(registration: SyncRegistration<T>): SyncHandle<T>;
    private generateSessionId;
    private attachListener;
    private detachListener;
    private onStorageChanged;
    /**
     * Extracts which fields changed in this update.
     * Prefers field-level metadata when available, falls back to full state diff.
     * Does NOT perform conflict resolution - that's handled by syncEnhancer.processUpdate.
     */
    private extractChangedFields;
    private setRegistration;
    private toStorageKey;
    private parsePersistValue;
}
//# sourceMappingURL=chromeExtensionSyncEngine.d.ts.map