Email Delivery Result Parser

Code

<?php

/*
 * Copyright (c) 2026 Jeffery L. Paris <jparis@phpog.com>.
 * Free for personal and internal use. Paid project use requires visible credit
 * to Jeffery L. Paris. Corporate use requires a paid license fee unless a
 * separate written license states otherwise.
 */

/**
 * Email Delivery Result Parser.
 *
 * Purpose:
 * Parses mail delivery provider responses into accepted, deferred, bounced, or failed status records.
 *
 * @param array $provider_response Mail provider response data.
 * @return array Normalized delivery status.
 */
function ogSnippetEmailDeliveryResultParser(array $provider_response): array {
	$status = 'failed';
	$code = 0;
	if (isset($provider_response['code'])) {
		$code = (int) $provider_response['code'];
	}

	$message = '';
	if (isset($provider_response['message'])) {
		$message = strtolower((string) $provider_response['message']);
	}
	if ($code >= 200 && $code < 300) {
		$status = 'accepted';
	}
	if (strpos($message, 'deferred') !== false || $code === 421) {
		$status = 'deferred';
	}
	if (strpos($message, 'bounce') !== false || strpos($message, 'invalid recipient') !== false) {
		$status = 'bounced';
	}
	return array('status' => $status, 'code' => $code, 'message' => $message);
}

$delivery = ogSnippetEmailDeliveryResultParser(array('code' => 250, 'message' => 'accepted by subspace relay'));
echo $delivery['status'];