/**
 * A set of logging levels
 *
 */
export declare enum LogLevel {
    Verbose = 0,
    Info = 1,
    Warning = 2,
    Error = 3,
    Off = 99,
}
/**
 * Interface that defines a log entry
 *
 */
export interface LogEntry {
    /**
     * The main message to be logged
     */
    message: string;
    /**
     * The level of information this message represents
     */
    level: LogLevel;
    /**
     * Any associated data that a given logging listener may choose to log or ignore
     */
    data?: any;
}
/**
 * Interface that defines a log listner
 *
 */
export interface LogListener {
    /**
     * Any associated data that a given logging listener may choose to log or ignore
     *
     * @param entry The information to be logged
     */
    log(entry: LogEntry): void;
}
/**
 * Class used to subscribe ILogListener and log messages throughout an application
 *
 */
export declare class Logger {
    private static _instance;
    static activeLogLevel: LogLevel;
    private static readonly instance;
    /**
     * Adds ILogListener instances to the set of subscribed listeners
     *
     * @param listeners One or more listeners to subscribe to this log
     */
    static subscribe(...listeners: LogListener[]): void;
    /**
     * Clears the subscribers collection, returning the collection before modifiction
     */
    static clearSubscribers(): LogListener[];
    /**
     * Gets the current subscriber count
     */
    static readonly count: number;
    /**
     * Writes the supplied string to the subscribed listeners
     *
     * @param message The message to write
     * @param level [Optional] if supplied will be used as the level of the entry (Default: LogLevel.Verbose)
     */
    static write(message: string, level?: LogLevel): void;
    /**
     * Writes the supplied string to the subscribed listeners
     *
     * @param json The json object to stringify and write
     * @param level [Optional] if supplied will be used as the level of the entry (Default: LogLevel.Verbose)
     */
    static writeJSON(json: any, level?: LogLevel): void;
    /**
     * Logs the supplied entry to the subscribed listeners
     *
     * @param entry The message to log
     */
    static log(entry: LogEntry): void;
    /**
     * Logs performance tracking data for the the execution duration of the supplied function using console.profile
     *
     * @param name The name of this profile boundary
     * @param f The function to execute and track within this performance boundary
     */
    static measure<T>(name: string, f: () => T): T;
}
/**
 * Implementation of ILogListener which logs to the browser console
 *
 */
export declare class ConsoleListener implements LogListener {
    /**
     * Any associated data that a given logging listener may choose to log or ignore
     *
     * @param entry The information to be logged
     */
    log(entry: LogEntry): void;
    /**
     * Formats the message
     *
     * @param entry The information to format into a string
     */
    private format(entry);
}
/**
 * Implementation of ILogListener which logs to the supplied function
 *
 */
export declare class FunctionListener implements LogListener {
    private method;
    /**
     * Creates a new instance of the FunctionListener class
     *
     * @constructor
     * @param  method The method to which any logging data will be passed
     */
    constructor(method: (entry: LogEntry) => void);
    /**
     * Any associated data that a given logging listener may choose to log or ignore
     *
     * @param entry The information to be logged
     */
    log(entry: LogEntry): void;
}