/**
 * Safe Regex Utilities - ReDoS Prevention
 *
 * Provides regex validation and safe execution with timeout protection.
 */
export interface RegexValidationResult {
    valid: boolean;
    error?: string;
}
export interface PCREConversionResult {
    pattern: string;
    flags: string;
    converted: boolean;
    error?: string;
}
/**
 * Convert PCRE inline modifiers to JavaScript flags
 * Handles: (?i), (?m), (?s), (?x), and combinations like (?im)
 */
export declare function convertPCREModifiers(pattern: string): PCREConversionResult;
/**
 * Validate a regex pattern for potential ReDoS vulnerabilities
 */
export declare function validateRegexPattern(pattern: string): RegexValidationResult;
/**
 * Pattern error metrics for monitoring
 */
export interface PatternErrorMetrics {
    pcreConversionFailures: number;
    validationFailures: number;
    regexCompilationFailures: number;
    totalPatternsProcessed: number;
}
/**
 * Get current pattern error metrics
 */
export declare function getPatternErrorMetrics(): Readonly<PatternErrorMetrics>;
/**
 * Reset pattern error metrics (useful for testing)
 */
export declare function resetPatternErrorMetrics(): void;
/**
 * Get a cached regex instance or create a new one
 */
export declare function getCachedRegex(pattern: string, flags?: string): RegExp | null;
/**
 * Execute regex with content length limit
 */
export declare function safeRegexExec(regex: RegExp, content: string, maxLength?: number): RegExpExecArray | null;
/**
 * Safe regex test with content length limit
 */
export declare function safeRegexTest(regex: RegExp, content: string, maxLength?: number): boolean;
/**
 * Create a safe regex with validation
 * Throws error if pattern is unsafe
 */
export declare function createSafeRegex(pattern: string, flags?: string): RegExp;
/**
 * Validate multiple regex patterns
 */
export declare function validateRegexPatterns(patterns: string[]): RegexValidationResult;