/**
 * Parses a comma-separated pattern string and configures the debug filter. Calling this function replaces any previous filter configuration.
 * @param pattern - Comma-separated list of category patterns (e.g., "tuning:hulu,recovery,-streaming:ffmpeg").
 */
export declare function initDebugFilter(pattern: string): void;
/**
 * Checks whether a specific debug category is enabled under the current filter configuration.
 * @param category - The category to check (e.g., "tuning:hulu", "recovery:tab").
 * @returns True if debug output should be produced for this category.
 */
export declare function isCategoryEnabled(category: string): boolean;
/**
 * Fast-path check for whether any debug categories are configured. When this returns false, callers can skip category string construction entirely.
 * @returns True if at least one debug category is enabled.
 */
export declare function isAnyDebugEnabled(): boolean;
/**
 * Reconstructs the current filter pattern string from internal state. Returns an empty string when no debug output is configured.
 * @returns The current pattern string (e.g., "*,-streaming:ffmpeg" or "tuning:hulu,recovery").
 */
export declare function getCurrentPattern(): string;
/**
 * Metadata for a known debug category. Used by the /debug UI to display available categories with descriptions.
 */
export interface DebugCategory {
    readonly category: string;
    readonly description: string;
}
/**
 * Static registry of all known debug categories with descriptions. Sorted alphabetically by category. The /debug endpoint uses this to render hierarchical checkboxes.
 * Parent groups (e.g., "streaming", "timing", "tuning") are derived by the UI from the colon-separated namespaces — only leaf categories are declared here.
 */
export declare const DEBUG_CATEGORIES: readonly DebugCategory[];
/**
 * Creates a lightweight elapsed-time closure using performance.now(). Call the returned function to get the elapsed milliseconds since creation.
 * @returns A closure that returns elapsed milliseconds as a number.
 */
export declare function startTimer(): () => number;