Logger.js

const HexUtil = require('./HexUtil');

class Logger {
    constructor() {
        this.debugEnabled = false;
        this.prefix = '';
    }

    debug(...args) {
        if (!this.debugEnabled) return;
        this._print(...args);
    }

    _print(...args) {
        try {
            const strings = this._convertArgsToStrings(...args);
            if (strings.length) {
                if (this.prefix) {
                    strings.unshift(this.prefix);
                }
                console.log(...strings);
            }
        } catch(e) {
            console.log("Error while logging: " + e);
        }
    }

    _convertArgsToStrings(...args) {
        const out = [];
        for (const arg of args) {
            if (arg instanceof Error) {
                out.push(arg.stack);
            } else if (arg instanceof Buffer) {
                out.push(HexUtil.debugDump(arg));
            } else if (typeof arg == 'function') {
                const result = arg.call(undefined, (...args) => this._print(...args));
                if (result !== undefined) out.push(...this._convertArgsToStrings(result));
            } else {
                out.push(arg);
            }
        }
        return out;
    }
}

module.exports = Logger;