const winston = require('winston');
const DailyRotateFile = require('winston-daily-rotate-file');
const path = require('path');

// Define log format
const logFormat = winston.format.combine(
    winston.format.timestamp({ format: 'YYYY-MM-DD HH:mm:ss' }),
    winston.format.errors({ stack: true }),
    winston.format.splat(),
    winston.format.json()
);

// Console format (more readable)
const consoleFormat = winston.format.combine(
    winston.format.colorize(),
    winston.format.timestamp({ format: 'YYYY-MM-DD HH:mm:ss' }),
    winston.format.printf(({ timestamp, level, message, ...meta }) => {
        let msg = `${timestamp} [${level}]: ${message}`;
        if (Object.keys(meta).length > 0) {
            msg += ` ${JSON.stringify(meta)}`;
        }
        return msg;
    })
);

// Create logs directory if it doesn't exist
const logsDir = path.join(__dirname, '..', 'logs');

// Logger configuration
const logger = winston.createLogger({
    level: process.env.LOG_LEVEL || 'info',
    format: logFormat,
    defaultMeta: { service: 'govt-travel-estimator' },
    transports: [
        // Error logs
        new DailyRotateFile({
            filename: path.join(logsDir, 'error-%DATE%.log'),
            datePattern: 'YYYY-MM-DD',
            level: 'error',
            maxFiles: '30d',
            maxSize: '20m'
        }),
        // Combined logs
        new DailyRotateFile({
            filename: path.join(logsDir, 'combined-%DATE%.log'),
            datePattern: 'YYYY-MM-DD',
            maxFiles: '14d',
            maxSize: '20m'
        }),
        // Console output
        new winston.transports.Console({
            format: consoleFormat
        })
    ],
    exceptionHandlers: [
        new DailyRotateFile({
            filename: path.join(logsDir, 'exceptions-%DATE%.log'),
            datePattern: 'YYYY-MM-DD',
            maxFiles: '30d'
        })
    ],
    rejectionHandlers: [
        new DailyRotateFile({
            filename: path.join(logsDir, 'rejections-%DATE%.log'),
            datePattern: 'YYYY-MM-DD',
            maxFiles: '30d'
        })
    ]
});

// Create a stream object for Morgan (HTTP request logging)
logger.stream = {
    write: (message) => {
        logger.info(message.trim());
    }
};

module.exports = logger;