<?php
/**
 * Store API cart extension data.
 *
 * @package Extrova
 */

declare( strict_types=1 );

namespace Extrova\StoreApi;

use Extrova\Core\ContextFactory;
use Extrova\Core\ExtraService;
use Extrova\Core\Money;
use Extrova\Goals\GoalService;
use Extrova\Pricing\TaxHelper;
use Extrova\Registry\TypeRegistry;

defined( 'ABSPATH' ) || exit;

/**
 * Adds `extensions['extrova']` to every Store API cart response. Because the
 * Store API returns the cart after quantity, coupon, address and shipping changes, visibility
 * and the progress bar refresh by themselves (no polling).
 *
 * @since 1.0.0
 */
final class CartExtension {

	public const STORE_NAMESPACE = 'extrova';

	/**
	 * Constructor.
	 *
	 * @param ExtraService   $service  Engine.
	 * @param ContextFactory $contexts Contexts.
	 * @param TypeRegistry   $types    Types.
	 * @param GoalService    $goals    Goals.
	 * @param TaxHelper      $tax      Tax helper.
	 */
	public function __construct(
		private ExtraService $service,
		private ContextFactory $contexts,
		private TypeRegistry $types,
		private GoalService $goals,
		private TaxHelper $tax
	) {}

	/**
	 * Registers the endpoint data.
	 */
	public function register(): void {
		if ( ! function_exists( 'woocommerce_store_api_register_endpoint_data' ) ) {
			return;
		}
		$endpoint = class_exists( \Automattic\WooCommerce\StoreApi\Schemas\V1\CartSchema::class )
			? \Automattic\WooCommerce\StoreApi\Schemas\V1\CartSchema::IDENTIFIER
			: 'cart';

		woocommerce_store_api_register_endpoint_data(
			array(
				'endpoint'        => $endpoint,
				'namespace'       => self::STORE_NAMESPACE,
				'data_callback'   => array( $this, 'data' ),
				'schema_callback' => array( $this, 'schema' ),
				'schema_type'     => ARRAY_A,
			)
		);
	}

	/**
	 * Response data.
	 */
	public function data(): array {
		$empty = array(
			'extras'     => array(),
			'selections' => array(),
			'goals'      => array(),
			'errors'     => array(),
			'display'    => 'excl',
		);

		$cart = function_exists( 'WC' ) ? WC()->cart : null;
		if ( ! $cart instanceof \WC_Cart ) {
			return $empty;
		}

		$context    = $this->contexts->from_cart( $cart, 'checkout_block' );
		$extras     = $this->service->get_visible_extras( $context );
		$context    = $context->with_offered( $extras );
		$selections = $this->service->get_selections_for( $extras );
		$decimals   = wc_get_price_decimals();
		$display    = $this->tax->display_including_tax( $context ) ? 'incl' : 'excl';

		$items  = array();
		$errors = array();
		foreach ( $extras as $extra_id => $extra ) {
			$type = $this->types->get( $extra->type );
			if ( ! $type ) {
				continue;
			}
			$prices = array();
			foreach ( $this->service->price_previews( $extra, $context ) as $key => $result ) {
				$prices[ '' === $key ? 'base' : $key ] = Money::to_minor( $result->display_amount );
			}
			$items[] = array(
				'id'                => $extra->id,
				'type'              => $extra->type,
				'label'             => $extra->label,
				'description'       => $extra->description,
				'required'          => $extra->required,
				'price'             => array(
					'amount'              => $prices['base'] ?? '0',
					'currency_minor_unit' => $decimals,
					'display'             => $display,
				),
				'prices'            => (object) $prices,
				'config'            => $type->to_client( $extra, $context ),
				'rule_dependencies' => $this->service->rule_dependencies( $extra ),
			);

			$valid = $this->service->validate_extra( $extra, $selections[ $extra_id ] ?? null, $context );
			if ( $valid instanceof \WP_Error ) {
				$errors[ $extra_id ] = $valid->get_error_message();
			}
		}

		$values = array();
		foreach ( $selections as $extra_id => $selection ) {
			$values[ $extra_id ] = $selection->value;
		}

		$goals = array();
		foreach ( $this->goals->evaluate_all( $context ) as $goal ) {
			$goals[] = array(
				'id'        => (string) $goal['id'],
				'threshold' => Money::to_minor( (string) $goal['threshold'] ),
				'current'   => Money::to_minor( (string) $goal['current'] ),
				'remaining' => Money::to_minor( (string) $goal['remaining'] ),
				'reached'   => (bool) $goal['reached'],
				'message'   => (string) $goal['message'],
			);
		}

		$data = array(
			'extras'     => $items,
			'selections' => (object) $values,
			'goals'      => $goals,
			'errors'     => (object) $errors,
			'display'    => $display,
		);

		/**
		 * Filters the data added to the Store API cart response.
		 *
		 * @since 1.0.0
		 *
		 * @param array   $data    Data.
		 * @param \Extrova\Core\Context $context Context.
		 */
		return (array) apply_filters( 'extrova_cart_extension_data', $data, $context );
	}

	/**
	 * Response schema.
	 */
	public function schema(): array {
		return array(
			'extras'     => array(
				'description' => __( 'Checkout extras visible for this cart.', 'extrova' ),
				'type'        => 'array',
				'context'     => array( 'view', 'edit' ),
				'readonly'    => true,
				'items'       => array( 'type' => 'object' ),
			),
			'selections' => array(
				'description' => __( 'Values chosen by the customer, keyed by extra id.', 'extrova' ),
				'type'        => 'object',
				'context'     => array( 'view', 'edit' ),
				'readonly'    => true,
			),
			'goals'      => array(
				'description' => __( 'Progress goals such as free shipping.', 'extrova' ),
				'type'        => 'array',
				'context'     => array( 'view', 'edit' ),
				'readonly'    => true,
				'items'       => array( 'type' => 'object' ),
			),
			'errors'     => array(
				'description' => __( 'Validation messages keyed by extra id.', 'extrova' ),
				'type'        => 'object',
				'context'     => array( 'view', 'edit' ),
				'readonly'    => true,
			),
			'display'    => array(
				'description' => __( 'Whether prices include tax (incl) or not (excl).', 'extrova' ),
				'type'        => 'string',
				'context'     => array( 'view', 'edit' ),
				'readonly'    => true,
			),
		);
	}
}