/**
 * Utility functions for RFC9110 Conditional Requests validation
 */
/**
 * Checks if an ETag is marked as weak (starts with W/)
 * @param etag The ETag value to check
 * @returns true if the ETag is weak, false otherwise
 */
export declare function isWeakETag(etag: string): boolean;
/**
 * Checks if an ETag is strong (not marked as weak)
 * @param etag The ETag value to check
 * @returns true if the ETag is strong, false otherwise
 */
export declare function isStrongETag(etag: string): boolean;
/**
 * Validates if a string is a valid HTTP-date according to RFC9110
 * Accepts IMF-fixdate, obsolete RFC 850, and ANSI C's asctime() format
 * @param date The date string to validate
 * @returns true if valid HTTP-date, false otherwise
 */
export declare function isValidHttpDate(date: string): boolean;
/**
 * Compares two ETags according to RFC9110 rules
 * @param etag1 First ETag to compare
 * @param etag2 Second ETag to compare
 * @param useWeakComparison If true, uses weak comparison; otherwise uses strong comparison
 * @returns true if ETags match according to the comparison type
 */
export declare function compareETags(etag1: string, etag2: string, useWeakComparison: boolean): boolean;
/**
 * Parses If-Match or If-None-Match header value into individual ETags
 * Handles both "*" and comma-separated ETag lists
 * @param headerValue The If-Match or If-None-Match header value
 * @returns Array of ETag strings, or ["*"] if the value is "*"
 */
export declare function parseConditionalETagHeader(headerValue: string): string[];
/**
 * Validates If-Match or If-None-Match header syntax
 * According to RFC9110, the header must not contain "*" mixed with other values
 * @param headerValue The If-Match or If-None-Match header value
 * @returns true if syntax is invalid (violation), false if valid
 */
export declare function hasInvalidConditionalETagSyntax(headerValue: string): boolean;
/**
 * Compares two HTTP dates
 * @param date1 First date string
 * @param date2 Second date string
 * @returns -1 if date1 < date2, 0 if equal, 1 if date1 > date2, null if invalid
 */
export declare function compareHttpDates(date1: string, date2: string): -1 | 0 | 1 | null;
//# sourceMappingURL=utils.d.ts.map