import { Request, Response, NextFunction } from 'express';
import pino from 'pino';

/**
 * Pino structured logger.
 * - Development: colorized, human-readable output
 * - Production: JSON for log aggregation
 */
export const logger = pino({
    level: process.env.LOG_LEVEL || 'info',
    ...(process.env.NODE_ENV !== 'production' && {
        transport: {
            target: 'pino-pretty',
            options: { colorize: true },
        },
    }),
});

/**
 * Request logging middleware.
 * Logs method, url, status, and duration for every request.
 */
export const requestLogger = (
    req: Request,
    res: Response,
    next: NextFunction
) => {
    const start = Date.now();

    res.on('finish', () => {
        const duration = Date.now() - start;
        logger.info({
            method: req.method,
            url: req.url,
            status: res.statusCode,
            duration: `${duration}ms`,
            ip: req.ip,
        });
    });

    next();
};