<?php
/**
 * WooCommerce integration: catalog behaviour, checkout fields and the
 * in-place cart endpoint.
 *
 * @package VyatkaShop
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Remove WooCommerce wrappers in favor of semantic theme templates.
 */
function vyatka_shop_woocommerce_hooks(): void {
	remove_action( 'woocommerce_before_main_content', 'woocommerce_output_content_wrapper', 10 );
	remove_action( 'woocommerce_after_main_content', 'woocommerce_output_content_wrapper_end', 10 );
	remove_action( 'woocommerce_sidebar', 'woocommerce_get_sidebar', 10 );
}
add_action( 'wp', 'vyatka_shop_woocommerce_hooks' );

/**
 * Respect the product-count control used by the archive toolbar.
 */
function vyatka_shop_products_per_page(): int {
	$requested = isset( $_GET['per_page'] ) ? absint( wp_unslash( $_GET['per_page'] ) ) : 25;
	return in_array( $requested, array( 12, 25, 50 ), true ) ? $requested : 25;
}
add_filter( 'loop_shop_per_page', 'vyatka_shop_products_per_page', 20 );

/**
 * Return the deterministic demo facets rendered by product cards.
 *
 * @param int $product_id Product ID.
 * @return array{feature:string,collection:string}
 */
function vyatka_shop_product_facets( int $product_id ): array {
	$features    = array( 'conifer', 'maple', 'birch', 'sea-buckthorn', 'rowan', 'blueberry', 'lingonberry' );
	$collections = array( 'pine', 'linden', 'aspen', 'juniper', 'cranberry', 'blackberry', 'raspberry' );

	return array(
		'feature'    => $features[ $product_id % count( $features ) ],
		'collection' => $collections[ $product_id % count( $collections ) ],
	);
}

/**
 * Apply the visible demo facets to the main product query so filtering,
 * sorting and pagination all operate on the same result set.
 *
 * @param WP_Query $query Main archive query.
 */
function vyatka_shop_filter_product_archive( WP_Query $query ): void {
	static $collecting_products = false;

	if (
		$collecting_products ||
		is_admin() ||
		! $query->is_main_query() ||
		( ! $query->is_post_type_archive( 'product' ) && ! $query->is_tax( 'product_cat' ) )
	) {
		return;
	}

	$selected_features   = isset( $_GET['feature'] )
		? array_values( array_diff( array_map( 'sanitize_key', (array) wp_unslash( $_GET['feature'] ) ), array( 'all', '' ) ) )
		: array();
	$selected_collection = isset( $_GET['collection'] ) ? sanitize_key( wp_unslash( $_GET['collection'] ) ) : '';
	$price_active        = isset( $_GET['filter_min_price'], $_GET['filter_max_price'] );

	if ( ! $selected_features && ! $selected_collection && ! $price_active ) {
		return;
	}

	$minimum_price = $price_active ? max( 0, absint( wp_unslash( $_GET['filter_min_price'] ) ) ) : 0;
	$maximum_price = $price_active ? max( $minimum_price, absint( wp_unslash( $_GET['filter_max_price'] ) ) ) : PHP_INT_MAX;

	$collecting_products = true;
	$product_ids         = get_posts(
		array(
			'post_type'        => 'product',
			'post_status'      => 'publish',
			'fields'           => 'ids',
			'posts_per_page'   => -1,
			'no_found_rows'    => true,
			'suppress_filters' => true,
		)
	);
	$collecting_products = false;

	if ( $query->is_tax( 'product_cat' ) ) {
		$term = get_queried_object();
		if ( $term instanceof WP_Term ) {
			$product_ids = array_values(
				array_filter(
					$product_ids,
					static fn( int $product_id ): bool => has_term( $term->term_id, 'product_cat', $product_id )
				)
			);
		}
	}

	$matching_ids = array_values(
		array_filter(
			$product_ids,
			static function ( int $product_id ) use ( $selected_features, $selected_collection, $price_active, $minimum_price, $maximum_price ): bool {
				$facets = vyatka_shop_product_facets( $product_id );
				$price  = (float) get_post_meta( $product_id, '_price', true );

				return ( ! $selected_features || in_array( $facets['feature'], $selected_features, true ) )
					&& ( ! $selected_collection || $facets['collection'] === $selected_collection )
					&& ( ! $price_active || ( $price >= $minimum_price && $price <= $maximum_price ) );
			}
		)
	);

	$query->set( 'post__in', $matching_ids ?: array( 0 ) );
	$query->set( 'paged', max( 1, absint( $query->get( 'paged' ) ) ) );
}
add_action( 'pre_get_posts', 'vyatka_shop_filter_product_archive', 25 );

/**
 * Use the wording shown in the design for the default product order.
 *
 * @param array<string,string> $options Ordering labels.
 * @return array<string,string>
 */
function vyatka_shop_catalog_orderby( array $options ): array {
	if ( isset( $options['menu_order'] ) ) {
		$options['menu_order'] = __( 'По умолчанию', 'vyatka-shop' );
	}
	return $options;
}
add_filter( 'woocommerce_catalog_orderby', 'vyatka_shop_catalog_orderby' );

/**
 * Adding a product is handled in place by the theme's AJAX control. Keeping
 * WooCommerce's redirect option disabled also prevents it from queueing a
 * second success message for the next page load.
 */
function vyatka_shop_disable_add_to_cart_redirect(): string {
	return 'no';
}
add_filter( 'pre_option_woocommerce_cart_redirect_after_add', 'vyatka_shop_disable_add_to_cart_redirect' );

/**
 * Success feedback is rendered by the client-side toast. Remove legacy
 * success notices left in the WooCommerce session before any frontend
 * template can print them into the document flow.
 */
function vyatka_shop_clear_legacy_success_notices(): void {
	if ( is_admin() || wp_doing_ajax() || ! function_exists( 'wc_get_notices' ) || ! function_exists( 'wc_set_notices' ) ) {
		return;
	}

	$notices = wc_get_notices();
	if ( ! isset( $notices['success'] ) ) {
		return;
	}

	unset( $notices['success'] );
	wc_set_notices( $notices );
}
add_action( 'wp', 'vyatka_shop_clear_legacy_success_notices', 20 );

/**
 * Calculate regular, current and sale-discount totals from one shared source.
 *
 * @param WC_Cart|null $cart Cart to summarize. Defaults to the active cart.
 * @return array{regular_total: float, current_total: float, discount_total: float}
 */
function vyatka_shop_cart_price_summary( ?WC_Cart $cart = null ): array {
	$cart          = $cart ?? WC()->cart;
	$regular_total = 0.0;
	$current_total = 0.0;

	if ( ! $cart ) {
		return array(
			'regular_total'  => 0.0,
			'current_total'  => 0.0,
			'discount_total' => 0.0,
		);
	}

	foreach ( $cart->get_cart() as $cart_item ) {
		$product  = $cart_item['data'] ?? null;
		$quantity = isset( $cart_item['quantity'] ) ? max( 0, (int) $cart_item['quantity'] ) : 0;

		if ( ! $product instanceof WC_Product || ! $product->exists() || 0 === $quantity ) {
			continue;
		}

		$current_price = max( 0.0, (float) $product->get_price() );
		$regular_price = (float) $product->get_regular_price();
		if ( $regular_price <= 0.0 ) {
			$regular_price = $current_price;
		}

		$regular_total += $regular_price * $quantity;
		$current_total += $current_price * $quantity;
	}

	return array(
		'regular_total'  => $regular_total,
		'current_total'  => $current_total,
		'discount_total' => max( 0.0, $regular_total - $current_total ),
	);
}

/**
 * Render the current cart state for an AJAX response.
 */
function vyatka_shop_render_cart_fragment(): string {
	ob_start();
	if ( WC()->cart->is_empty() ) {
		wc_get_template( 'cart/cart-empty.php' );
	} else {
		wc_get_template( 'cart/cart.php' );
	}
	$html = (string) ob_get_clean();

	return vyatka_shop_relative_frontend_urls( $html );
}

/**
 * Mutate the WooCommerce cart without navigating away from the current page.
 */
function vyatka_shop_ajax_cart_mutation(): void {
	check_ajax_referer( 'vyatka-cart', 'nonce' );

	if ( ! function_exists( 'WC' ) ) {
		wp_send_json_error( array( 'message' => __( 'Корзина недоступна.', 'vyatka-shop' ) ), 503 );
	}
	if ( null === WC()->cart && function_exists( 'wc_load_cart' ) ) {
		wc_load_cart();
	}
	if ( null === WC()->cart ) {
		wp_send_json_error( array( 'message' => __( 'Корзина недоступна.', 'vyatka-shop' ) ), 503 );
	}

	$operation = isset( $_POST['operation'] ) ? sanitize_key( wp_unslash( $_POST['operation'] ) ) : '';

	if ( 'add' === $operation ) {
		$product_id = isset( $_POST['product_id'] ) ? absint( wp_unslash( $_POST['product_id'] ) ) : 0;
		$quantity   = isset( $_POST['quantity'] ) ? max( 1, absint( wp_unslash( $_POST['quantity'] ) ) ) : 1;
		$product    = wc_get_product( $product_id );

		if ( ! $product || ! $product->is_purchasable() || ! $product->is_in_stock() ) {
			wp_send_json_error( array( 'message' => __( 'Товар нельзя добавить в корзину.', 'vyatka-shop' ) ), 400 );
		}

		$maximum = $product->get_max_purchase_quantity();
		if ( 0 < $maximum ) {
			$quantity = min( $quantity, $maximum );
		}

		$existing_key = '';
		foreach ( WC()->cart->get_cart() as $cart_item_key => $cart_item ) {
			if ( $product_id === (int) $cart_item['product_id'] && empty( $cart_item['variation_id'] ) ) {
				$existing_key = $cart_item_key;
				break;
			}
		}

		$changed = '' !== $existing_key
			? WC()->cart->set_quantity( $existing_key, $quantity, false )
			: WC()->cart->add_to_cart( $product_id, $quantity );
		if ( false === $changed ) {
			wp_send_json_error( array( 'message' => __( 'Не удалось добавить товар в корзину.', 'vyatka-shop' ) ), 400 );
		}
	} elseif ( 'update' === $operation ) {
		$cart_item_key = isset( $_POST['cart_item_key'] )
			? wc_clean( wp_unslash( $_POST['cart_item_key'] ) )
			: '';
		$quantity      = isset( $_POST['quantity'] ) ? max( 1, absint( wp_unslash( $_POST['quantity'] ) ) ) : 1;
		$cart_item     = WC()->cart->get_cart_item( $cart_item_key );

		if ( ! $cart_item ) {
			wp_send_json_error( array( 'message' => __( 'Товар в корзине не найден.', 'vyatka-shop' ) ), 404 );
		}

		$product = $cart_item['data'];
		$maximum = $product instanceof WC_Product ? $product->get_max_purchase_quantity() : -1;
		if ( 0 < $maximum ) {
			$quantity = min( $quantity, $maximum );
		}
		if ( false === WC()->cart->set_quantity( $cart_item_key, $quantity, false ) ) {
			wp_send_json_error( array( 'message' => __( 'Не удалось изменить количество.', 'vyatka-shop' ) ), 400 );
		}
	} elseif ( 'remove' === $operation ) {
		$cart_item_key = isset( $_POST['cart_item_key'] )
			? wc_clean( wp_unslash( $_POST['cart_item_key'] ) )
			: '';
		if ( '' === $cart_item_key || false === WC()->cart->remove_cart_item( $cart_item_key ) ) {
			wp_send_json_error( array( 'message' => __( 'Не удалось удалить товар.', 'vyatka-shop' ) ), 400 );
		}
	} else {
		wp_send_json_error( array( 'message' => __( 'Неизвестная операция с корзиной.', 'vyatka-shop' ) ), 400 );
	}

	WC()->cart->calculate_totals();
	WC()->cart->set_session();

	wp_send_json_success(
		array(
			'cartCount' => WC()->cart->get_cart_contents_count(),
			'html'      => vyatka_shop_render_cart_fragment(),
		)
	);
}
add_action( 'wp_ajax_vyatka_cart_mutation', 'vyatka_shop_ajax_cart_mutation' );
add_action( 'wp_ajax_nopriv_vyatka_cart_mutation', 'vyatka_shop_ajax_cart_mutation' );

/**
 * Keep only the three customer fields present in the checkout design.
 *
 * @param array<string,array<string,array<string,mixed>>> $fields Checkout fields.
 * @return array<string,array<string,array<string,mixed>>>
 */
function vyatka_shop_checkout_fields( array $fields ): array {
	// WooCommerce prefixes billing labels with "Выставление счёта", which turns
	// a validation message into "Выставление счёта Имя — обязательное поле".
	// The design labels these fields plainly, and the shorter label is also
	// what the inline field errors match on.
	$labels = array(
		'billing_first_name' => __( 'Имя', 'vyatka-shop' ),
		'billing_phone'      => __( 'Телефон', 'vyatka-shop' ),
		'billing_email'      => __( 'Email', 'vyatka-shop' ),
	);

	$billing = array();
	foreach ( $labels as $key => $label ) {
		if ( isset( $fields['billing'][ $key ] ) ) {
			$billing[ $key ]             = $fields['billing'][ $key ];
			$billing[ $key ]['required'] = true;
			$billing[ $key ]['label']    = $label;
		}
	}
	$fields['billing']  = $billing;
	$fields['shipping'] = array();
	$fields['order']    = array();
	return $fields;
}
add_filter( 'woocommerce_checkout_fields', 'vyatka_shop_checkout_fields' );

/**
 * Validate the delivery-only address field exposed by the checkout switch.
 */
function vyatka_shop_validate_delivery_fields(): void {
	$delivery_type = isset( $_POST['delivery_type'] ) ? sanitize_key( wp_unslash( $_POST['delivery_type'] ) ) : 'pickup';
	$address       = isset( $_POST['delivery_address'] ) ? sanitize_text_field( wp_unslash( $_POST['delivery_address'] ) ) : '';

	if ( 'delivery' === $delivery_type && '' === $address ) {
		wc_add_notice( __( 'Укажите адрес доставки.', 'vyatka-shop' ), 'error' );
	}
}
add_action( 'woocommerce_checkout_process', 'vyatka_shop_validate_delivery_fields' );

/**
 * Store custom delivery controls with the order.
 *
 * @param WC_Order $order Order being created.
 */
function vyatka_shop_save_delivery_fields( WC_Order $order ): void {
	$fields = array( 'delivery_type', 'pickup_address', 'delivery_address', 'delivery_unit' );
	foreach ( $fields as $field ) {
		if ( isset( $_POST[ $field ] ) ) {
			$order->update_meta_data( '_' . $field, sanitize_text_field( wp_unslash( $_POST[ $field ] ) ) );
		}
	}
}
add_action( 'woocommerce_checkout_create_order', 'vyatka_shop_save_delivery_fields' );