/* eslint-disable @typescript-eslint/no-unused-vars */
/* eslint-disable @typescript-eslint/no-empty-function */
/** @module log */

import { IContext } from 'pip-services4-components-node';

import { ILogger } from './ILogger';
import { LogLevel } from './LogLevel';

/**
 * Dummy implementation of logger that doesn't do anything.
 * 
 * It can be used in testing or in situations when logger is required
 * but shall be disabled.
 * 
 * @see [[ILogger]]
 */
export class NullLogger implements ILogger {

    /**
     * Creates a new instance of the logger.
     */
    public constructor() { }

    /**
     * Gets the maximum log level. 
     * Messages with higher log level are filtered out.
     * 
     * @returns the maximum log level.
     */
    public getLevel(): LogLevel { return LogLevel.None; }

    /**
     * Set the maximum log level.
     * 
     * @param value     a new maximum log level.
     */
    public setLevel(value: LogLevel): void { }

    /**
     * Logs a message at specified log level.
     * 
     * @param level             a log level.
     * @param context     (optional) a context to trace execution through call chain.
     * @param error             an error object associated with this message.
     * @param message           a human-readable message to log.
     * @param args              arguments to parameterize the message. 
     */
    public log(level: LogLevel, context: IContext, error: Error, message: string, ...args: any[]): void { }

    /**
     * Logs fatal (unrecoverable) message that caused the process to crash.
     * 
     * @param context     (optional) a context to trace execution through call chain.
     * @param error             an error object associated with this message.
     * @param message           a human-readable message to log.
     * @param args              arguments to parameterize the message. 
     */
    public fatal(context: IContext, error: Error, message: string, ...args: any[]): void { }

    /**
     * Logs recoverable application error.
     * 
     * @param context     (optional) a context to trace execution through call chain.
     * @param error             an error object associated with this message.
     * @param message           a human-readable message to log.
     * @param args              arguments to parameterize the message. 
     */
    public error(context: IContext, error: Error, message: string, ...args: any[]): void { }

    /**
     * Logs a warning that may or may not have a negative impact.
     * 
     * @param context     (optional) a context to trace execution through call chain.
     * @param message           a human-readable message to log.
     * @param args              arguments to parameterize the message. 
     */
    public warn(context: IContext, message: string, ...args: any[]): void { }

    /**
     * Logs an important information message
     * 
     * @param context     (optional) a context to trace execution through call chain.
     * @param message           a human-readable message to log.
     * @param args              arguments to parameterize the message. 
     */
    public info(context: IContext, message: string, ...args: any[]): void { }

    /**
     * Logs a high-level debug information for troubleshooting.
     * 
     * @param context     (optional) a context to trace execution through call chain.
     * @param message           a human-readable message to log.
     * @param args              arguments to parameterize the message. 
     */
    public debug(context: IContext, message: string, ...args: any[]): void { }
    
    /**
     * Logs a low-level debug information for troubleshooting. 
     * 
     * @param context     (optional) a context to trace execution through call chain.
     * @param message           a human-readable message to log.
     * @param args              arguments to parameterize the message. 
     */
    public trace(context: IContext, message: string, ...args: any[]): void { }
}