#!/usr/bin/env php
<?php
/**
 * Newsletter Queue Worker
 *
 * Processes queued emails via wp_mail() using configured SMTP settings.
 *
 * This script runs as a standalone CLI process, independent of WordPress cron.
 * It loads WordPress with DOING_CRON defined to prevent triggering actual cron.
 *
 * Usage: php worker.php <batch_size> <worker_id>
 * Example: php worker.php 10 "w1"
 * Parallel: seq 1 10 | xargs -P10 -I{} php worker.php 10 "w{}"
 *
 * @package ROBOTSTXT_SMTP_Newsletter
 * @since 2.2.0
 */

// Security: CLI-only execution.
if ( php_sapi_name() !== 'cli' ) {
	http_response_code( 403 );
	die( 'Forbidden: This script must be run from command line' );
}

// Parse command-line arguments.
if ( $argc < 3 ) {
	fwrite( STDERR, "Usage: php worker.php <batch_size> <worker_id>\n" );
	fwrite( STDERR, "Example: php worker.php 10 \"w1\"\n" );
	exit( 1 );
}

$batch_size = max( 1, (int) $argv[1] );
$worker_id  = $argv[2];

// Load WordPress.
define( 'DOING_CRON', true );

// Find wp-load.php (3 levels up from plugin directory).
$wp_load_path = __DIR__ . '/../../../wp-load.php';

if ( ! file_exists( $wp_load_path ) ) {
	fwrite( STDERR, "Error: Could not find wp-load.php at {$wp_load_path}\n" );
	exit( 1 );
}

require_once $wp_load_path;

// Verify plugin is active.
if ( ! defined( 'ROBOTSTXT_SMTP_NEWSLETTER_VERSION' ) ) {
	fwrite( STDERR, "Error: Newsletter SMTP plugin is not active\n" );
	exit( 1 );
}

// Get queue and statistics instances.
$queue = \Robotstxt_SMTP_Newsletter\Queue::get_instance();
$stats = \Robotstxt_SMTP_Newsletter\Statistics::get_instance();

// Process batch.
$items = $queue->get_and_lock_batch( $batch_size, $worker_id );

if ( empty( $items ) ) {
	echo "No items to process\n";
	exit( 0 );
}

echo sprintf( "Worker %s: Processing %d emails...\n", $worker_id, count( $items ) );

$success_count = 0;
$failure_count = 0;

foreach ( $items as $item ) {
	try {
		// Build headers array.
		$headers = array();

		// Add From header if specified.
		if ( ! empty( $item->from_email ) ) {
			$from = ! empty( $item->from_name )
				? sprintf( '%s <%s>', $item->from_name, $item->from_email )
				: $item->from_email;
			$headers[] = 'From: ' . $from;
		}

		// Add Reply-To header if specified.
		if ( ! empty( $item->reply_to ) ) {
			$headers[] = 'Reply-To: ' . $item->reply_to;
		}

		// Add Content-Type header (prefer HTML if available).
		if ( ! empty( $item->body_html ) ) {
			$headers[] = 'Content-Type: text/html; charset=UTF-8';
		}

		// Decode and add custom headers from JSON.
		if ( ! empty( $item->headers_json ) ) {
			$custom = json_decode( $item->headers_json, true );
			if ( is_array( $custom ) ) {
				foreach ( $custom as $key => $value ) {
					$headers[] = sprintf( '%s: %s', $key, $value );
				}
			}
		}

		// Select body (prefer HTML over text).
		$body = ! empty( $item->body_html ) ? $item->body_html : $item->body_text;

		if ( empty( $body ) ) {
			throw new \Exception( 'Email body is empty' );
		}

		// Send via wp_mail (uses core SMTP configuration).
		$result = wp_mail(
			$item->to_email,
			$item->subject,
			$body,
			$headers
		);

		if ( $result ) {
			$queue->mark_sent( $item->id );
			$success_count++;
			echo sprintf( "  ✓ Sent: %s\n", $item->to_email );
		} else {
			$queue->mark_failed( $item->id, 'wp_mail returned false' );
			$failure_count++;
			echo sprintf( "  ✗ Failed: %s (wp_mail returned false)\n", $item->to_email );
		}

	} catch ( \Exception $e ) {
		$queue->mark_failed( $item->id, $e->getMessage() );
		$failure_count++;
		echo sprintf( "  ✗ Error: %s - %s\n", $item->to_email, $e->getMessage() );
	}
}

// Sync statistics after batch processing.
$stats->sync_from_queue();

echo sprintf(
	"Worker %s: Done. Success: %d, Failed: %d\n",
	$worker_id,
	$success_count,
	$failure_count
);

exit( 0 );