/**
 * @publicApi
 */
export type LogLevel = 'log' | 'error' | 'warn' | 'debug' | 'verbose' | 'fatal';
/**
 * @publicApi
 */
export interface LoggerService {
    /**
     * Write a 'log' level log.
     */
    log(message: any, ...optionalParams: any[]): any;
    /**
     * Write an 'error' level log.
     */
    error(message: any, ...optionalParams: any[]): any;
    /**
     * Write a 'warn' level log.
     */
    warn(message: any, ...optionalParams: any[]): any;
    /**
     * Write a 'debug' level log.
     */
    debug?(message: any, ...optionalParams: any[]): any;
    /**
     * Write a 'verbose' level log.
     */
    verbose?(message: any, ...optionalParams: any[]): any;
    /**
     * Write a 'fatal' level log.
     */
    fatal?(message: any, ...optionalParams: any[]): any;
    /**
     * Set log levels.
     * @param levels log levels
     */
    setLogLevels?(levels: LogLevel[]): any;
}
interface LogBufferRecord {
    /**
     * Method to execute.
     */
    methodRef: Function;
    /**
     * Arguments to pass to the method.
     */
    arguments: unknown[];
}
/**
 * @publicApi
 */
export declare class Logger implements LoggerService {
    protected context?: string;
    protected options: {
        timestamp?: boolean;
    };
    protected static logBuffer: LogBufferRecord[];
    protected static staticInstanceRef?: LoggerService;
    protected static logLevels?: LogLevel[];
    private static isBufferAttached;
    protected localInstanceRef?: LoggerService;
    private static WrapBuffer;
    constructor();
    constructor(context: string);
    constructor(context: string, options?: {
        timestamp?: boolean;
    });
    get localInstance(): LoggerService;
    /**
     * Write an 'error' level log.
     */
    error(message: any, stack?: string, context?: string): void;
    error(message: any, ...optionalParams: [...any, string?, string?]): void;
    /**
     * Write a 'log' level log.
     */
    log(message: any, context?: string): void;
    log(message: any, ...optionalParams: [...any, string?]): void;
    /**
     * Write a 'warn' level log.
     */
    warn(message: any, context?: string): void;
    warn(message: any, ...optionalParams: [...any, string?]): void;
    /**
     * Write a 'debug' level log.
     */
    debug(message: any, context?: string): void;
    debug(message: any, ...optionalParams: [...any, string?]): void;
    /**
     * Write a 'verbose' level log.
     */
    verbose(message: any, context?: string): void;
    verbose(message: any, ...optionalParams: [...any, string?]): void;
    /**
     * Write a 'fatal' level log.
     */
    fatal(message: any, context?: string): void;
    fatal(message: any, ...optionalParams: [...any, string?]): void;
    /**
     * Write an 'error' level log.
     */
    static error(message: any, stackOrContext?: string): void;
    static error(message: any, context?: string): void;
    static error(message: any, stack?: string, context?: string): void;
    static error(message: any, ...optionalParams: [...any, string?, string?]): void;
    /**
     * Write a 'log' level log.
     */
    static log(message: any, context?: string): void;
    static log(message: any, ...optionalParams: [...any, string?]): void;
    /**
     * Write a 'warn' level log.
     */
    static warn(message: any, context?: string): void;
    static warn(message: any, ...optionalParams: [...any, string?]): void;
    /**
     * Write a 'debug' level log, if the configured level allows for it.
     * Prints to `stdout` with newline.
     */
    static debug(message: any, context?: string): void;
    static debug(message: any, ...optionalParams: [...any, string?]): void;
    /**
     * Write a 'verbose' level log.
     */
    static verbose(message: any, context?: string): void;
    static verbose(message: any, ...optionalParams: [...any, string?]): void;
    /**
     * Write a 'fatal' level log.
     */
    static fatal(message: any, context?: string): void;
    static fatal(message: any, ...optionalParams: [...any, string?]): void;
    /**
     * Print buffered logs and detach buffer.
     */
    static flush(): void;
    /**
     * Attach buffer.
     * Turns on initialization logs buffering.
     */
    static attachBuffer(): void;
    /**
     * Detach buffer.
     * Turns off initialization logs buffering.
     */
    static detachBuffer(): void;
    static getTimestamp(): string;
    static overrideLogger(logger: LoggerService | LogLevel[] | boolean): any;
    static isLevelEnabled(level: LogLevel): boolean;
    private registerLocalInstanceRef;
}
export {};