example.config.ts

import type { Level } from 'pino'
import z from 'zod'
import { EnvConfigParser } from './src'
import fs from 'node:fs'
import path from 'node:path'

const parser = new EnvConfigParser({
    onValidationError: 'silent',
    mode: 'schema',
})

const config = {
    // Application Settings
    ...parser.section('============================'),
    ...parser.section('==== Application Settings ===='),
    ...parser.section('============================'),
    NODE_ENV: parser.string('NODE_ENV', 'development', val => {
        if (val && ['development', 'production', 'test'].includes(val))
            return val
        throw new Error(
            'NODE_ENV must be one of "development", "production", "test"'
        )
    }),
    PORT: parser.number('PORT', 3000),
    HOST: parser.string('HOST', '0.0.0.0'),
    APP_SECRET: parser.string(
        'APP_SECRET',
        'supersecretjwtkeythatshouldbeverylongandcomplex'
    ),

    // Database Configuration
    ...parser.section(),
    ...parser.section('========================='),
    ...parser.section('==== Database Config ===='),
    ...parser.section('========================='),
    DATABASE_URL: parser.string(
        'DATABASE_URL',
        'postgresql://user:password@localhost:5432/mydb'
    ),
    DB_MAX_CONNECTIONS: parser.integer('DB_MAX_CONNECTIONS', 10),
    DB_SSL_ENABLED: parser.boolean('DB_SSL_ENABLED', false),

    // API Keys and External Services
    ...parser.section(),
    ...parser.section('=============================='),
    ...parser.section('==== External API Config ===='),
    ...parser.section('=============================='),
    STRIPE_SECRET_KEY: parser.string('STRIPE_SECRET_KEY', ''),
    GOOGLE_MAPS_API_KEY: parser.string('GOOGLE_MAPS_API_KEY', ''),
    TWILIO_ACCOUNT_SID: parser.string('TWILIO_ACCOUNT_SID', ''),
    TWILIO_AUTH_TOKEN: parser.string('TWILIO_AUTH_TOKEN', ''),
    TWILIO_PHONE_NUMBER: parser.string('TWILIO_PHONE_NUMBER', ''),

    // Logging Configuration
    ...parser.section(),
    ...parser.section('========================'),
    ...parser.section('==== Logging Config ===='),
    ...parser.section('========================'),
    LOG_LEVEL: parser.string('LOG_LEVEL', 'info', inVal => {
        const val = inVal ? inVal.toLowerCase() : 'info'
        const valid = ['fatal', 'error', 'warn', 'info', 'debug', 'trace']
        if (valid.includes(val)) return val
        console.error(
            `[Config Warning] Invalid log level 'LOG_LEVEL': '${inVal}'. Defaulting to 'info'`
        )
        return 'info'
    }) as Level,
    LOG_JSON_FORMAT: parser.boolean('LOG_JSON_FORMAT', false),
    LOG_PRETTY_PRINT: parser.boolean('LOG_PRETTY_PRINT', true),

    // Feature Flags
    ...parser.section(),
    ...parser.section('======================'),
    ...parser.section('==== Feature Flags ===='),
    ...parser.section('======================'),
    FEATURE_ANALYTICS_ENABLED: parser.boolean(
        'FEATURE_ANALYTICS_ENABLED',
        true
    ),
    FEATURE_NEW_DASHBOARD: parser.boolean('FEATURE_NEW_DASHBOARD', false),

    // Advanced Settings
    ...parser.section(),
    ...parser.section('========================'),
    ...parser.section('==== Advanced Config ===='),
    ...parser.section('========================'),
    CACHE_TTL_SECONDS: parser.number('CACHE_TTL_SECONDS', 3600),
    RATE_LIMIT_ENABLED: parser.boolean('RATE_LIMIT_ENABLED', true),
    ALLOWED_ORIGINS: parser.zValidator(
        'ALLOWED_ORIGINS',
        z
            .array(z.string())
            .transform(val =>
                Array.isArray(val) ? val : val.split(',').map(s => s.trim())
            ),
        ['*']
    ),

    // Example of using passThrough for sensitive data (e.g., private keys)
    ...parser.section(),
    ...parser.section('========================'),
    ...parser.section('==== Sensitive Data ===='),
    ...parser.section('========================'),
    RSA_PRIVATE_KEY: parser.passThrough('RSA_PRIVATE_KEY'),
}

export default config

// Script to generate .env.example
if (require.main === module) {
    try {
        const template = parser.getTemplateString()
            const outputPath = path.resolve(__dirname, 'example.config.env')
            fs.writeFileSync(outputPath, template)
            console.log(`Successfully generated .env template at ${outputPath}`)    } catch (error) {
        console.error('Failed to generate .env.example:', error)
        process.exit(1)
    }
}