// Import necessary modules
import debug from 'debug';
import { config } from 'dotenv';
config();
import { promises as fs } from 'fs';
import { join, dirname } from 'path';
import { inspect } from 'util';

/**
 * Write a given message to the log file
 * @param {any} logMessage The message to write to the log file
 * @param {string} appName The app name that created the log entry
 */
const writeToLog = async (logMessage, appName) => {
    const logLocation = join(process.env.LOG_LOCATION ?? `./logs/${appName}.log`);

    // Ensure the log directory exists
    try {
        await fs.mkdir(dirname(logLocation), { recursive: true });
    } catch (err) {
        console.error(err);
    }    

    // Ensure the message is a string
    logMessage = `${String(logMessage)}\n`;

    // Write to the file
    try {
        await fs.writeFile(logLocation, logMessage, { encoding: 'utf-8', flag: 'a+' });
    } catch (err) {
        console.error(err);
    }
};

/**
 * Create the different logging methods for a function
 * Namespace template = ("[app]:[fileName]:['INFO', 'WARNING', 'DEBUG', 'ERROR']")
 * @param {string} appName The name of the app to be used in the 'app' portion of the namespace
 * @param {string} fileName The name of the file calling the builder to be used in the 'fileName' portion of the namespace
 */
export class DebugBuilder {
    constructor(appName, fileName) {
        const buildLogger = (level) => (...messageParts) => {
            const logger = debug(`${appName}:${fileName}:${level}`);
            logger(messageParts);

            const timeStamp = new Date().toLocaleString('en-US', { timeZone: 'America/New_York' });
            const message = `${timeStamp} - ${appName}:${fileName}:${level}\t-\t${messageParts.map(part => inspect(part)).join(' ')}`;

            // Write to console
            console.log(message);
            
            // Write to logfile
            writeToLog(message, appName);
        };

        this.INFO = buildLogger('INFO');
        this.DEBUG = buildLogger('DEBUG');
        this.VERBOSE = buildLogger('VERBOSE');
        this.WARN = buildLogger('WARNING');
        this.ERROR = (...messageParts) => {
            buildLogger('ERROR')(...messageParts);

            if (process.env.EXIT_ON_ERROR && process.env.EXIT_ON_ERROR > 0) {
                writeToLog("!--- EXITING ---!", appName);
                const exitDelay = parseInt(process.env.EXIT_ON_ERROR_DELAY, 10) || 0;
                setTimeout(() => process.exit(1), exitDelay);
            }
        };
    }
}