interface IEnvRule {
	key: string;
	required?: boolean;
	default?: string;
}

export const validateEnv = (): string[] => {
	const requiredEnvs: IEnvRule[] = [
		{ key: "PORT", default: "5000" },
		{ key: "MONGO_URI", required: true },
		{ key: "JWT_SECRET", required: true },
		{ key: "JWT_REFRESH_SECRET", required: true },
		{ key: "FRONTEND_URL", required: true },
		{ key: "NODE_ENV", default: "development" },
	];

	const missingEnvs: string[] = [];
	const warnings: string[] = [];

	requiredEnvs.forEach((env: IEnvRule) => {
		if (!process.env[env.key]) {
			if (env.required) {
				missingEnvs.push(env.key);
			} else if (env.default) {
				process.env[env.key] = env.default;
				warnings.push(
					`${env.key} not set, using default value: ${env.default}`
				);
			}
		}
	});

	if (missingEnvs.length > 0) {
		throw new Error(
			`Missing required environment variables: ${missingEnvs.join(
				", "
			)}\n` +
				`Please check your .env file and ensure all required variables are set.`
		);
	}
	return warnings;
};