Add upstream

wp-content/plugins/jetpack/class.jetpack-affiliate.php

@@ -0,0 +1,78 @@
+<?php
+
+if ( ! defined( 'ABSPATH' ) ) {
+	// Exit if accessed directly
+	exit;
+}
+
+/**
+ * This class introduces routines to get an affiliate code, that might be obtained from:
+ * - an `jetpack_affiliate_code` option in the WP database
+ * - an affiliate code returned by a filter bound to the `jetpack_affiliate_code` filter hook
+ *
+ * @since 6.9.0
+ */
+class Jetpack_Affiliate {
+
+	/**
+	 * @since 6.9.0
+	 * @var Jetpack_Affiliate This class instance.
+	 **/
+	private static $instance = null;
+
+	private function __construct() {
+		if ( Jetpack::is_development_mode() ) {
+			return;
+		}
+	}
+
+	/**
+	 * Initializes the class or returns the singleton
+	 *
+	 * @since 6.9.0
+	 *
+	 * @return Jetpack_Affiliate | false
+	 */
+	public static function init() {
+		if ( is_null( self::$instance ) ) {
+			self::$instance = new Jetpack_Affiliate;
+		}
+		return self::$instance;
+	}
+
+	/**
+	 * Returns the affiliate code from database after filtering it.
+	 *
+	 * @since 6.9.0
+	 *
+	 * @return string The affiliate code.
+	 */
+	public function get_affiliate_code() {
+		/**
+		 * Allow to filter the affiliate code.
+		 *
+		 * @since 6.9.0
+		 *
+		 * @param string $aff_code The affiliate code, blank by default.
+		 */
+		return apply_filters( 'jetpack_affiliate_code', get_option( 'jetpack_affiliate_code', '' ) );
+	}
+
+	/**
+	 * Returns the passed URL with the affiliate code added as a URL query arg.
+	 *
+	 * @since 6.9.0
+	 *
+	 * @param string $url The URL where the code will be added.
+	 *
+	 * @return string The passed URL with the code added.
+	 */
+	public function add_code_as_query_arg( $url ) {
+		if ( '' !== ( $aff = $this->get_affiliate_code() ) ) {
+			$url = add_query_arg( 'aff', $aff, $url );
+		}
+		return $url;
+	}
+}
+
+add_action( 'init', array( 'Jetpack_Affiliate', 'init' ) );