import { BaseCheck } from '../base_check.ts';
import type { HealthCheckResult } from '../types.ts';
/**
 * Checks the memory heap size and reports warning or error after a
 * certain threshold is exceeded. Thresholds can be defined as absolute
 * byte values or as percentages of the maximum V8 heap size limit
 *
 * @example
 * ```typescript
 * // Using byte thresholds
 * const heapCheckBytes = new MemoryHeapCheck()
 *   .as('Heap memory usage check (bytes)')
 *   .warnWhenExceeds('200 mb')
 *   .failWhenExceeds('300 mb')
 *   .cacheFor('30s')
 *
 * // Using percentage thresholds
 * const heapCheckPercentage = new MemoryHeapCheck()
 *   .as('Heap memory usage check (percentage)')
 *   .warnWhenExceedsPercentage(80) // Warning at 80% of max heap
 *   .failWhenExceedsPercentage(90) // Error at 90% of max heap
 *   .cacheFor('30s')
 *
 * const resultBytes = await heapCheckBytes.run()
 * console.log(resultBytes.status) // 'ok' | 'warning' | 'error'
 *
 * const resultPercentage = await heapCheckPercentage.run()
 * console.log(resultPercentage.status) // 'ok' | 'warning' | 'error'
 * ```
 */
export declare class MemoryHeapCheck extends BaseCheck {
    #private;
    /**
     * The name of the memory heap check
     */
    name: string;
    /**
     * Defines the heap threshold after which a warning
     * should be created. This method sets a byte-based threshold
     *
     * The value should be either a number in bytes or a value expression string
     *
     * @param value - The threshold value as bytes (number) or string expression (e.g., '200 mb')
     *
     * @example
     * ```typescript
     * const check = new MemoryHeapCheck().warnWhenExceeds('200 mb')
     * // or
     * const check2 = new MemoryHeapCheck().warnWhenExceeds(209715200) // 200 MB in bytes
     * ```
     */
    warnWhenExceeds(value: string | number): this;
    /**
     * Defines the heap threshold after which an error
     * should be created. This method sets a byte-based threshold
     *
     * The value should be either a number in bytes or a value expression string
     *
     * @param value - The threshold value as bytes (number) or string expression (e.g., '500 mb')
     *
     * @example
     * ```typescript
     * const check = new MemoryHeapCheck().failWhenExceeds('500 mb')
     * // or
     * const check2 = new MemoryHeapCheck().failWhenExceeds(524288000) // 500 MB in bytes
     * ```
     */
    failWhenExceeds(value: string | number): this;
    /**
     * Defines the percentage threshold after which a warning
     * should be created. This method sets a percentage-based threshold
     * relative to the V8 heap size limit
     *
     * @param valueInPercentage - The percentage threshold for warnings (0-100)
     *
     * @example
     * ```typescript
     * const check = new MemoryHeapCheck().warnWhenExceedsPercentage(80)
     * ```
     */
    warnWhenExceedsPercentage(valueInPercentage: number): this;
    /**
     * Defines the percentage threshold after which an error
     * should be created. This method sets a percentage-based threshold
     * relative to the V8 heap size limit
     *
     * @param valueInPercentage - The percentage threshold for errors (0-100)
     *
     * @example
     * ```typescript
     * const check = new MemoryHeapCheck().failWhenExceedsPercentage(90)
     * ```
     */
    failWhenExceedsPercentage(valueInPercentage: number): this;
    /**
     * Defines a custom callback to compute the heap size. Defaults to
     * using the "process.memoryUsage()" method call
     *
     * @param callback - Function that returns memory usage information
     *
     * @example
     * ```typescript
     * const heapCheck = new MemoryHeapCheck()
     *   .compute(() => {
     *     // Custom memory computation logic
     *     const usage = process.memoryUsage()
     *     return { ...usage, heapUsed: usage.heapUsed * 0.8 } // Custom adjustment
     *   })
     * ```
     */
    compute(callback: () => NodeJS.MemoryUsage): this;
    /**
     * Executes the heap memory usage check
     */
    run(): Promise<HealthCheckResult>;
}