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// config/index.js — centralised config module
require('dotenv').config();

const config = {
    development: {
        port:     process.env.PORT || 3000,
        db:       { host: 'localhost', port: 5432, name: 'myapp_dev' },
        logLevel: 'debug',
        debug:    true,
    },
    test: {
        port:     process.env.PORT || 3001,
        db:       { host: 'localhost', port: 5432, name: 'myapp_test' },
        logLevel: 'error',
        debug:    false,
    },
    production: {
        port:     process.env.PORT || 8080,
        db: {
            host: process.env.DB_HOST,
            port: parseInt(process.env.DB_PORT, 10),
            name: process.env.DB_NAME,
        },
        logLevel: 'warn',
        debug:    false,
    },
};

const env = process.env.NODE_ENV || 'development';

if (!config[env]) {
    throw new Error(`Unknown NODE_ENV: ${env}`);
}

module.exports = config[env];

// Usage in other files:
// const config = require('./config');
// console.log(config.db.host);
// console.log(config.port);