<?php
/**
 * Order events: delivery.
 *
 * @package CortexCommerce
 */

namespace CortexCommerce\Orders;

use CortexCommerce\Settings\Config;
use CortexCommerce\Settings\Options;
use CortexCommerce\Support\Log;

defined( 'ABSPATH' ) || exit;

/**
 * Runs as an Action Scheduler action, never during checkout. Builds the body fresh on every attempt (so `ts` is
 * current), signs it like the lifecycle events (contract §4), and reschedules itself on network errors, 408, 429
 * and 5xx. A refusal (other 4xx, including any 3xx: redirects are never followed) stops at once: retrying cannot
 * fix a bad signature, an unknown tenant, or a URL the backend has moved.
 */
final class OrderEventSender {

	const DELAYS  = array( 60, 300, 1800, 7200, 43200 );
	const TIMEOUT = 10;

	/**
	 * @param mixed $event     'order.paid' | 'order.refunded'.
	 * @param mixed $order_id  Order id.
	 * @param mixed $refund_id Refund id (order.refunded only).
	 * @param mixed $attempt   Attempts already made.
	 */
	public static function run( $event, $order_id, $refund_id = 0, $attempt = 0 ): void {
		try {
			$body = self::body( (string) $event, (int) $order_id, (int) $refund_id );
			if ( null === $body ) {
				return;
			}
			if ( 'retry' === self::post( $body ) ) {
				self::retry( (string) $event, (int) $order_id, (int) $refund_id, (int) $attempt );
			}
		} catch ( \Throwable $e ) {
			Log::error( 'Order event failed: ' . $e->getMessage() );
		}
	}

	public static function body( string $event, int $order_id, int $refund_id ): ?string {
		if ( ! Options::is_connected() || '' === Options::webhook_secret() ) {
			return null;
		}
		$order = wc_get_order( $order_id );
		if ( ! $order instanceof \WC_Order ) {
			return null;
		}
		if ( 'order.paid' === $event ) {
			return (string) wp_json_encode( OrderEventPayload::paid( $order ) );
		}
		if ( 'order.refunded' === $event ) {
			$refund = wc_get_order( $refund_id );
			return $refund instanceof \WC_Order_Refund ? (string) wp_json_encode( OrderEventPayload::refunded( $order, $refund ) ) : null;
		}
		return null;
	}

	/**
	 * @return string 'sent', 'retry' or 'stop'.
	 */
	public static function post( string $body ): string {
		$response = wp_remote_post(
			Config::api_base() . '/webhooks/woo/orders',
			array(
				'timeout'     => self::TIMEOUT,
				'redirection' => 0,
				'sslverify'   => true,
				'headers'     => array(
					'Content-Type'       => 'application/json',
					// phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.obfuscation_base64_encode -- HMAC signature encoding, as in contract §4.
					'X-Cortex-Signature' => base64_encode( hash_hmac( 'sha256', $body, Options::webhook_secret(), true ) ),
				),
				'body'        => $body,
			)
		);
		if ( is_wp_error( $response ) ) {
			return 'retry';
		}
		$status = (int) wp_remote_retrieve_response_code( $response );
		if ( $status >= 200 && $status < 300 ) {
			return 'sent';
		}
		// 3xx is a permanent refusal here: redirection is 0 above, so we never follow one, and there is no
		// sense in which a redirect would resolve itself on a later attempt.
		if ( 0 === $status || 408 === $status || 429 === $status || $status >= 500 ) {
			return 'retry';
		}
		Log::warning( 'CortexCommerce refused an order event: HTTP ' . $status );
		return 'stop';
	}

	private static function retry( string $event, int $order_id, int $refund_id, int $attempt ): void {
		if ( $attempt >= count( self::DELAYS ) ) {
			Log::warning( sprintf( 'Order event %s for order %d not delivered after %d attempts.', $event, $order_id, $attempt + 1 ) );
			return;
		}
		as_schedule_single_action( time() + self::DELAYS[ $attempt ], OrderEvents::HOOK, array( $event, $order_id, $refund_id, $attempt + 1 ), OrderEvents::GROUP );
	}
}