<?php
/**
 * @package Polylang-WC
 */

namespace WP_Syntex\Polylang_WC\Cart;

use WP_Term;
use PLL_Language;
use PLLWC_Data_Store;
use PLLWC_Product_Language_CPT;

/**
 * A class to manage the cart item.
 *
 * @since 2.2
 *
 * @phpstan-type CartItem array{
 *   product_id: int,
 *   variation_id: int,
 *   variation: array,
 *   data: \WC_Product,
 *   quantity: int,
 *   key: string,
 * }
 */
class Item {
	/**
	 * The cart item.
	 *
	 * @var array
	 * @phpstan-var CartItem
	 */
	private $item;

	/**
	 * The product language data store.
	 *
	 * @var PLLWC_Product_Language_CPT
	 */
	private $data_store;

	/**
	 * Whether the cart item is a variation.
	 *
	 * @var bool
	 */
	private $is_variation = false;

	/**
	 * Constructor.
	 *
	 * @since 2.2
	 *
	 * @param array $item The cart item array.
	 * @phpstan-param CartItem $item
	 */
	public function __construct( array $item ) {
		$this->item         = $item;
		$this->data_store   = PLLWC_Data_Store::load( 'product_language' );
		$this->is_variation = ! empty( $item['variation_id'] );
	}

	/**
	 * Translates the cart item to the specified language.
	 *
	 * @since 2.2
	 *
	 * @param PLL_Language $lang The target language.
	 * @return array<string, mixed> The translated cart item array.
	 */
	public function translate( PLL_Language $lang ): array {
		$untranslated_items = $this->item;
		if (
			( $this->is_variation && ! $this->translate_variation( $lang ) )
			|| ! $this->translate_parent( $lang )
		) {
			return $untranslated_items;
		}

		/**
		 * Filters a cart item when it is translated.
		 *
		 * @since 0.6
		 *
		 * @param array  $item Cart item.
		 * @param string $lang Language code.
		 * @phpstan-param CartItem $item
		 */
		$this->item = apply_filters( 'pllwc_translate_cart_item', $this->item, $lang->slug );

		/**
		 * Filters the cart item data.
		 * This filters aims to replace the filter 'woocommerce_add_cart_item_data',
		 * which can't be used here as it conflicts with WooCommerce Bookings,
		 * which uses the filter to create new bookings and not only to filter the cart item data.
		 *
		 * @since 0.7.4
		 *
		 * @param array $cart_item_data Cart item data.
		 * @param array $item           Cart item.
		 * @phpstan-param CartItem $item
		 */
		$cart_item_data    = (array) apply_filters( 'pllwc_add_cart_item_data', array(), $this->item );
		$this->item['key'] = WC()->cart->generate_cart_id( $this->item['product_id'], $this->item['variation_id'], $this->item['variation'], $cart_item_data );

		return $this->item;
	}

	/**
	 * Translates a variation cart item to the specified language.
	 *
	 * @since 2.2
	 *
	 * @param PLL_Language $lang The target language.
	 * @return bool Whether the variation was translated.
	 */
	private function translate_variation( PLL_Language $lang ): bool {
		/** @var PLL_Language|false $orig_lang */
		$orig_lang = $this->data_store->get_language( $this->item['variation_id'], \OBJECT );

		if ( ! $orig_lang || $lang->slug === $orig_lang->slug ) {
			return false;
		}

		$tr_id = $this->data_store->get( $this->item['variation_id'], $lang );
		if ( empty( $tr_id ) ) {
			return false;
		}

		$tr_variation = wc_get_product( $tr_id );
		if ( ! $tr_variation ) {
			return false;
		}

		$this->item['variation_id'] = $tr_variation->get_id();
		$this->item['data']         = $tr_variation;
		$this->item['variation']    = $this->translate_attributes( $this->item['variation'], $lang, $orig_lang );

		return true;
	}

	/**
	 * Translates a simple product cart item to the specified language.
	 *
	 * @since 2.2
	 *
	 * @param PLL_Language $lang The target language.
	 * @return bool Whether the parent was translated.
	 */
	private function translate_parent( PLL_Language $lang ): bool {
		$tr_id = $this->data_store->get( $this->item['product_id'], $lang );
		if ( empty( $tr_id ) || $tr_id === $this->item['product_id'] ) {
			return false;
		}

		$tr_product = wc_get_product( $tr_id );
		if ( ! $tr_product ) {
			return false;
		}

		$this->item['product_id'] = $tr_product->get_id();
		$this->item['data']       = $tr_product;

		return true;
	}

	/**
	 * Translates product variation attributes to the specified language.
	 *
	 * @since 2.2
	 *
	 * @param array<string, string> $attributes The variation attributes array.
	 * @param PLL_Language          $lang       The target language.
	 * @param PLL_Language          $orig_lang   The original language.
	 * @return array<string, string> The translated attributes array.
	 */
	public function translate_attributes( array $attributes, PLL_Language $lang, PLL_Language $orig_lang ): array {
		foreach ( $attributes as $name => $value ) {
			if ( '' === $value ) {
				continue;
			}

			$taxonomy = wc_attribute_taxonomy_name( str_replace( 'attribute_pa_', '', urldecode( $name ) ) );

			if ( ! taxonomy_exists( $taxonomy ) ) {
				continue;
			}

			// Don't use get_term_by( 'slug' ) which is filtered in the current language by Polylang Pro.
			$terms = get_terms( array( 'taxonomy' => $taxonomy, 'slug' => $value, 'lang' => $orig_lang->slug ) );

			if ( empty( $terms ) || ! is_array( $terms ) ) {
				continue;
			}

			$term = reset( $terms );
			if ( ! $term instanceof WP_Term ) {
				continue;
			}

			$term_id = pll_get_term( $term->term_id, $lang );
			if ( ! $term_id ) {
				continue;
			}

			$term = get_term( $term_id, $taxonomy );
			if ( ! $term instanceof WP_Term ) {
				continue;
			}

			$attributes[ $name ] = $term->slug;
		}

		return $attributes;
	}
}