/**
 * Ensure archive directory exists, create if needed
 * @param dirPath - Absolute path to archive directory
 */
export declare function ensureArchiveDir(dirPath: string): Promise<void>;
/**
 * Generate archive filename from date with timestamp
 * Format: observability-archive-YYYY-MM-DD-{timestamp}.db
 */
export declare function generateArchiveFilename(date: Date, timestamp?: number): string;
/**
 * List all archive files in directory, sorted by date (newest first)
 * Only returns files matching the archive filename pattern
 */
export declare function listArchiveFiles(dirPath: string): Promise<string[]>;
/**
 * Delete an archive file with safety checks
 * @param filePath - Absolute path to archive file
 */
export declare function deleteArchiveFile(filePath: string): Promise<void>;
/**
 * Acquire file lock to prevent concurrent archive operations
 * @param lockPath - Path to lock file
 * @returns Release function, or null if lock is already held
 */
export declare function acquireFileLock(lockPath: string): Promise<(() => Promise<void>) | null>;
/**
 * Release file lock
 * @param release - Release function returned by acquireFileLock
 */
export declare function releaseFileLock(release: () => Promise<void>): Promise<void>;
/**
 * Calculate SHA256 checksum for a file
 * @param filePath - Absolute path to file
 * @returns Hex-encoded SHA256 checksum
 */
export declare function calculateFileChecksum(filePath: string): Promise<string>;
/**
 * Verify archive file integrity using checksum
 * @param archivePath - Absolute path to archive file
 * @param expectedChecksum - Expected SHA256 checksum
 * @returns True if checksum matches, false otherwise
 */
export declare function verifyArchiveIntegrity(archivePath: string, expectedChecksum: string): Promise<boolean>;
/**
 * Check available disk space in bytes
 * @param dirPath - Directory path to check
 * @returns Available space in bytes
 */
export declare function checkDiskSpace(dirPath: string): Promise<number>;
/**
 * Clean up old archive files, keeping only the newest maxFiles
 * @param archivesDir - Archive directory path
 * @param maxFiles - Maximum number of archive files to keep
 * @returns List of deleted archive filenames
 */
export declare function cleanupOldArchives(archivesDir: string, maxFiles: number): Promise<string[]>;
