Fixes translation support

Fixes #151

includes/class-main.php

@@ -96,6 +96,15 @@ final class Main {
 	 */
 	public $styles;
 
+	/**
+	 * Language Handler.
+	 *
+	 * @since 3.3.0
+	 *
+	 * @var object Language Handler.
+	 */
+	public $language;
+
 	/**
 	 * Gets the instance of the class.
 	 *
@@ -127,13 +136,14 @@ private function __construct() {
 	 * @since 3.3.0
 	 */
 	private function init() {
+		$this->language   = new Frontend\Language_Handler();
+		$this->styles     = new Frontend\Styles_Handler();
 		$this->counter    = new Counter();
 		$this->tracker    = new Tracker();
 		$this->shortcodes = new Frontend\Shortcodes();
 		$this->blocks     = new Frontend\Blocks\Blocks();
 		$this->filters    = new Frontend\Filters();
 		$this->feed       = new Frontend\Feed();
-		$this->styles     = new Frontend\Styles_Handler();
 
 		$this->hooks();
 
@@ -162,8 +172,6 @@ public function hooks() {
 	 * @since 3.3.0
 	 */
 	public function initiate_plugin() {
-		load_plugin_textdomain( 'top-10', false, dirname( plugin_basename( TOP_TEN_PLUGIN_FILE ) ) . '/languages/' );
-
 		Frontend\Media_Handler::add_image_sizes();
 	}
 

includes/frontend/class-language-handler.php

@@ -0,0 +1,125 @@
+<?php
+/**
+ * Language handler
+ *
+ * @package Top_Ten
+ */
+
+namespace WebberZone\Top_Ten\Frontend;
+
+// If this file is called directly, abort.
+if ( ! defined( 'WPINC' ) ) {
+	die;
+}
+
+/**
+ * Language handler class.
+ *
+ * @since 3.3.3
+ */
+class Language_Handler {
+
+	/**
+	 * Constructor.
+	 *
+	 * @since 3.3.3
+	 */
+	public function __construct() {
+		add_action( 'plugins_loaded', array( $this, 'load_plugin_textdomain' ) );
+		add_filter( 'top_ten_query_the_posts', array( $this, 'translate_ids' ), 999 );
+	}
+
+	/**
+	 * Initialises text domain for l10n.
+	 *
+	 * @since 3.3.3
+	 *
+	 * @return void
+	 */
+	public static function load_plugin_textdomain() {
+		load_plugin_textdomain( 'top-10', false, dirname( plugin_basename( TOP_TEN_PLUGIN_FILE ) ) . '/languages/' );
+	}
+
+	/**
+	 * Get the ID of a post in the current language. Works with WPML and PolyLang.
+	 *
+	 * @since 3.3.3
+	 *
+	 * @param int[] $results Arry of Posts.
+	 * @return \WP_Post[] Updated array of WP_Post objects.
+	 */
+	public static function translate_ids( $results ) {
+		global $post;
+
+		$processed_ids     = array();
+		$processed_results = array();
+
+		foreach ( $results as $result ) {
+
+			$result = self::object_id_cur_lang( $result );
+			if ( ! $result ) {
+				continue;
+			}
+
+			// If this is NULL or already processed ID or matches current post then skip processing this loop.
+			if ( ! $result->ID || in_array( $result->ID, $processed_ids ) ) { // phpcs:ignore WordPress.PHP.StrictInArray.MissingTrueStrict
+				continue;
+			}
+
+			// Push the current ID into the array to ensure we're not repeating it.
+			array_push( $processed_ids, $result->ID );
+
+			// Let's get the Post using the ID.
+			$result = get_post( $result );
+			array_push( $processed_results, $result );
+		}
+		return $processed_results;
+	}
+
+	/**
+	 * Returns the object identifier for the current language (WPML).
+	 *
+	 * @since 3.3.3
+	 *
+	 * @param int|string|\WP_Post $post Post object or Post ID.
+	 * @return \WP_Post|array|null Post opbject, updated if needed.
+	 */
+	public static function object_id_cur_lang( $post ) {
+
+		$return_original_if_missing = false;
+
+		$post         = get_post( $post );
+		$current_lang = apply_filters( 'wpml_current_language', null );
+
+		// Polylang implementation.
+		if ( function_exists( 'pll_get_post' ) ) {
+			$post = \pll_get_post( $post->ID );
+			$post = get_post( $post );
+		}
+
+		// WPML implementation.
+		if ( class_exists( 'SitePress' ) ) {
+			/**
+			 * Filter to modify if the original language ID is returned.
+			 *
+			 * @since 2.2.3
+			 *
+			 * @param bool $return_original_if_missing Flag to return original post ID if translated post ID is missing.
+			 * @param int  $id                         Post ID
+			 */
+			$return_original_if_missing = apply_filters( 'tptn_wpml_return_original', $return_original_if_missing, $post->ID );
+
+			$post = apply_filters( 'wpml_object_id', $post->ID, $post->post_type, $return_original_if_missing, $current_lang );
+			$post = get_post( $post );
+		}
+
+		/**
+		 * Filters Post object for current language.
+		 *
+		 * @since 2.1.0
+		 *
+		 * @param \WP_Post|array|null $id Post object.
+		 */
+		return apply_filters( 'tptn_object_id_cur_lang', $post );
+	}
+}