<?php
/**
 * Polylang Integration.
 *
 * Adds multilingual support for schema and feeds when Polylang is active.
 *
 * @package AICommerce\Integrations
 */

declare(strict_types=1);

namespace AICommerce\Integrations;

/**
 * Integrates AICommerce with Polylang for per-language schema and feeds.
 */
class PolylangIntegration {

	/**
	 * Whether Polylang is available.
	 *
	 * @return bool
	 */
	public static function is_available(): bool {
		return function_exists( 'pll_languages_list' );
	}

	/**
	 * Register all Polylang hooks.
	 *
	 * @return void
	 */
	public function register(): void {
		if ( ! self::is_available() ) {
			return;
		}

		add_filter( 'aicommerce/schema/product', array( $this, 'add_hreflang' ), 10, 2 );
		add_action( 'aicommerce/feed/after_generate', array( $this, 'trigger_language_feeds' ) );
	}

	/**
	 * Add hreflang sameAs links to product schema for all translated versions.
	 *
	 * @param array       $schema  The product schema array.
	 * @param \WC_Product $product The WooCommerce product.
	 *
	 * @return array Modified schema with sameAs links.
	 */
	public function add_hreflang( array $schema, \WC_Product $product ): array {
		$languages = pll_languages_list( array( 'fields' => 'slug' ) );

		if ( count( $languages ) < 2 ) {
			return $schema;
		}

		if ( ! isset( $schema['sameAs'] ) ) {
			$schema['sameAs'] = array();
		}

		$product_id = $product->get_id();

		foreach ( $languages as $lang_slug ) {
			$translated_id = pll_get_post( $product_id, $lang_slug );

			if ( $translated_id && $translated_id !== $product_id ) {
				$url = get_permalink( $translated_id );

				if ( $url ) {
					$schema['sameAs'][] = $url;
				}
			}
		}

		// Add current language.
		if ( function_exists( 'pll_current_language' ) ) {
			$current_lang = pll_current_language( 'slug' );
			if ( $current_lang ) {
				$schema['inLanguage'] = $current_lang;
			}
		}

		return $schema;
	}

	/**
	 * Trigger feed generation for each active language.
	 *
	 * @param string $feed_type The feed type that was generated.
	 *
	 * @return void
	 */
	public function trigger_language_feeds( string $feed_type ): void {
		$languages = pll_languages_list( array( 'fields' => 'slug' ) );

		if ( count( $languages ) < 2 ) {
			return;
		}

		foreach ( $languages as $lang_slug ) {
			if ( function_exists( 'PLL' ) && method_exists( PLL(), 'curlang' ) ) {
				// Switch Polylang context (best effort).
				do_action( 'pll_language', $lang_slug ); // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound -- Third-party Polylang integration hook.
			}

			if ( function_exists( 'as_schedule_single_action' ) ) {
				as_schedule_single_action(
					time(),
					'aicommerce_generate_feed',
					array( 'feed_type' => $feed_type . '_' . $lang_slug )
				);
			}
		}
	}
}