import type { ClassConstructor } from 'class-transformer';
/**
 * Interface for cache
 * Implementers SHALL ensure minimal logic outside of promise resolution or async function to prevent lag
 * Users of this interface can assume these methods behave asynchronously
 */
export interface ICache {
    exists(key: string, namespace?: string): Promise<boolean>;
    /**
     * Returns true if any keys exist in the given namespace.
     *
     * @param {string} namespace - The namespace to check.
     * @returns {Promise<boolean>} - Returns true if at least one key exists in the namespace.
     * */
    existsAnyInNamespace(namespace: string): Promise<boolean>;
    remove<T>(key: string, namespace?: string): Promise<T | null>;
    /**
     * Monitors a key for potential changes to its value.
     * If key-value does not exist this method will wait for it to exist or return null at the end of the wait period.
     * If value is removed, the method will return null.
     *
     * @param {string} key - The key for the value.
     * @param {number} [waitSeconds] - The number of seconds after which the method should return if the value has not been modified by then.
     * @param {string} [namespace] - The namespace for the key.
     * @returns {Promise<string | null>} Returns the value as string once it is modified or waitSeconds has elapsed; or null if the key does not exist.
     * */
    onChange<T>(key: string, waitSeconds: number, namespace?: string, classConstructor?: () => ClassConstructor<T>): Promise<T | null>;
    /**
     * Gets a value asynchronously from the underlying cache.
     *
     * @param {string} key - The key for the value.
     * @param {string} [namespace] - The namespace for the key.
     * @returns {Promise<string | null>} - Returns the value as string or null if the key does not exist.
     * */
    get<T>(key: string, namespace?: string, classConstructor?: () => ClassConstructor<T>): Promise<T | null>;
    /**
     * Sets a value asynchronously in the underlying cache.
     *
     * @param {string} key - The key for the value.
     * @param {string} value - The value to set.
     * @param {string} [namespace] - The namespace for the key.
     * @param {number} [expireSeconds] - The number of seconds after which the key should expire.
     * @returns {Promise<boolean>} - Returns true if the value was set successfully.
     * */
    set(key: string, value: string, namespace?: string, expireSeconds?: number): Promise<boolean>;
    /**
     * Sets a value asynchronously in the underlying cache if it doesn't exist. Returns false if the key already exists.
     *
     * @param {string} key - The key for the value.
     * @param {string} value - The value to set.
     * @param {string} [namespace] - The namespace for the key.
     * @param {number} [expireSeconds] - The number of seconds after which the key should expire.
     * @returns {Promise<boolean>} - Returns true if the value was set successfully.
     * */
    setIfNotExist(key: string, value: string, namespace?: string, expireSeconds?: number): Promise<boolean>;
    /**
     * Updates the expiration of a key without modifying its value. Returns false if the key does not exist.
     *
     * @param {string} key - The key to update.
     * @param {number} expireSeconds - The number of seconds from now after which the key should expire.
     * @param {string} [namespace] - The namespace for the key.
     * @returns {Promise<boolean>} - Returns true if the expiration was updated successfully, false if the key does not exist.
     * */
    updateExpiration(key: string, expireSeconds: number, namespace?: string): Promise<boolean>;
    /**
     * Pings the cache to check if it is responsive, for health checks. Implementers should ensure this method is lightweight and does not cause significant delay.
     *
     * @returns {Promise<void>} - Resolves if the cache is responsive, rejects if it is not.
     */
    ping(): Promise<void>;
}