/**
 * Debug performance instrumentation (Phase 3)
 *
 * Collection is disabled by default. Hook functions are called from
 * production hot paths even when disabled. Disabled-path runtime and
 * bundle overhead are tracked separately and must not be assumed negligible.
 *
 * See issue #119 for validation status.
 */
export interface CellCacheMetrics {
    createCellCalls: number;
    charCellWidthCallsFromCreateCell: number;
    newCellCount: number;
    cellCacheHitWidth1: number;
    cellCacheHitWidth2: number;
    cellCacheMissWidth1: number;
    cellCacheMissWidth2: number;
    cellCacheClearWidth1: number;
    cellCacheClearWidth2: number;
    blankCellCacheHit: number;
    blankCellCacheMiss: number;
    continuationCellCacheHit: number;
    continuationCellCacheMiss: number;
    maxCacheSizeWidth1: number;
    maxCacheSizeWidth2: number;
    registeredBucketCountWidth1: number;
    registeredBucketCountWidth2: number;
    registeredBucketSizeP50Width1: number;
    registeredBucketSizeP95Width1: number;
    registeredBucketSizeMaxWidth1: number;
    registeredBucketSizeP50Width2: number;
    registeredBucketSizeP95Width2: number;
    registeredBucketSizeMaxWidth2: number;
    estimatedRegisteredBucketCells: number;
}
export interface TextCacheMetrics {
    textCellWidthCalls: number;
    textWidthCacheHit: number;
    textWidthCacheMiss: number;
    textWidthCacheSet: number;
    textWidthCacheEvict: number;
    renderPassTextWidthCacheHit: number;
    renderPassTextWidthCacheMiss: number;
    wrapByCellsCalls: number;
    wrapCacheHit: number;
    wrapCacheMiss: number;
    wrapCacheSet: number;
    wrapCacheClear: number;
    wrapWidthBucketMapClear: number;
    maxTextLength: number;
    totalTextLength: number;
    asciiFastPathCount: number;
    nonAsciiOrNoFastPathCount: number;
}
export interface GraphemeMetrics {
    graphemeSegmentationRequiredCalls: number;
    intlSegmenterUsed: number;
    fallbackSegmenterUsed: number;
    segmentationRequiredInputCount: number;
}
export interface PerformanceMetrics {
    cell: CellCacheMetrics;
    text: TextCacheMetrics;
    grapheme: GraphemeMetrics;
    heapUsedBefore?: number;
    heapUsedAfter?: number;
    gcCount?: number;
}
/**
 * Enable instrumentation collection
 */
export declare function enableInstrumentation(): void;
/**
 * Disable instrumentation collection
 */
export declare function disableInstrumentation(): void;
/**
 * Check if instrumentation is enabled
 */
export declare function isInstrumentationEnabled(): boolean;
/**
 * Reset all metrics to zero
 */
export declare function resetMetrics(): void;
/**
 * Get current metrics snapshot
 */
export declare function getMetrics(): PerformanceMetrics;
/**
 * Get heap used bytes (Node.js or Chrome)
 */
export declare function getHeapUsed(): number | null;
/**
 * Get metrics with heap information
 *
 * Note: heapUsedBefore/After measures GC impact, not workload memory.
 * To measure workload memory, call getHeapUsed() before/after your workload.
 */
export declare function getMetricsWithHeap(): PerformanceMetrics;
export declare const cellInstr: {
    recordCreateCellCall(): void;
    recordCharCellWidthCall(): void;
    recordNewCell(): void;
    recordCacheHit(width: 1 | 2): void;
    recordCacheMiss(width: 1 | 2): void;
    recordCacheClear(width: 1 | 2): void;
    recordBlankCacheHit(): void;
    recordBlankCacheMiss(): void;
    recordContinuationCacheHit(): void;
    recordContinuationCacheMiss(): void;
    updateMaxCacheSize(width: 1 | 2, size: number): void;
    registerCacheBucket(width: 1 | 2, bucket: Map<string, any>): void;
    updateBucketCounts(width1Count: number, width2Count: number): void;
    updateEstimatedRetainedCells(count: number): void;
};
export declare const textInstr: {
    recordTextCellWidthCall(textLength: number, isAscii: boolean): void;
    recordTextWidthCacheHit(): void;
    recordTextWidthCacheMiss(): void;
    recordTextWidthCacheSet(): void;
    recordTextWidthCacheEvict(): void;
    recordRenderPassCacheHit(): void;
    recordRenderPassCacheMiss(): void;
    recordWrapByCellsCall(): void;
    recordWrapCacheHit(): void;
    recordWrapCacheMiss(): void;
    recordWrapCacheSet(): void;
    recordWrapCacheClear(): void;
    recordWrapWidthBucketMapClear(): void;
};
export declare const graphemeInstr: {
    recordSegmentedGraphemesCall(): void;
    recordIntlSegmenterUsed(): void;
    recordFallbackSegmenterUsed(): void;
    recordSegmentationRequiredInput(): void;
};