<?php
/**
 * Evaluation context.
 *
 * @package Extrova
 */

declare( strict_types=1 );

namespace Extrova\Core;

defined( 'ABSPATH' ) || exit;

/**
 * Snapshot of what rules and prices may look at. Built once per calculation.
 *
 * @since 1.0.0
 */
final readonly class Context {

	/**
	 * Location used when charging fees: matches every registered location.
	 */
	public const LOCATION_ANY = 'any';

	/**
	 * Constructor.
	 *
	 * @param \WC_Cart|null     $cart              Cart.
	 * @param \WC_Customer|null $customer          Customer.
	 * @param string            $location          `checkout_block`, `checkout_classic`, `any`...
	 * @param string[]          $shipping_methods  Chosen shipping method rate ids.
	 * @param string            $payment_method    Chosen payment method id.
	 * @param string            $currency          Currency code.
	 * @param bool              $is_recurring_cart Whether it is a Subscriptions recurring cart.
	 * @param Extra[]           $offered_extras    Extras offered (visible) at this point, keyed by id.
	 * @param array             $data              Free bag for adapters (e.g. price previews).
	 */
	public function __construct(
		public ?\WC_Cart $cart,
		public ?\WC_Customer $customer,
		public string $location,
		public array $shipping_methods = array(),
		public string $payment_method = '',
		public string $currency = '',
		public bool $is_recurring_cart = false,
		public array $offered_extras = array(),
		public array $data = array()
	) {}

	/**
	 * Copy with the offered extras.
	 *
	 * @param Extra[] $extras Extras keyed by id.
	 */
	public function with_offered( array $extras ): self {
		return new self( $this->cart, $this->customer, $this->location, $this->shipping_methods, $this->payment_method, $this->currency, $this->is_recurring_cart, $extras, $this->data );
	}

	/**
	 * Copy with a data entry.
	 *
	 * @param string $key   Key.
	 * @param mixed  $value Value.
	 */
	public function with_data( string $key, mixed $value ): self {
		$data         = $this->data;
		$data[ $key ] = $value;
		return new self( $this->cart, $this->customer, $this->location, $this->shipping_methods, $this->payment_method, $this->currency, $this->is_recurring_cart, $this->offered_extras, $data );
	}

	/**
	 * Copy with another location.
	 *
	 * @param string $location Location.
	 */
	public function with_location( string $location ): self {
		return new self( $this->cart, $this->customer, $location, $this->shipping_methods, $this->payment_method, $this->currency, $this->is_recurring_cart, $this->offered_extras, $this->data );
	}

	/**
	 * Reads a data entry.
	 *
	 * @param string $key      Key.
	 * @param mixed  $fallback Value when missing.
	 * @return mixed
	 */
	public function get( string $key, mixed $fallback = null ): mixed {
		return array_key_exists( $key, $this->data ) ? $this->data[ $key ] : $fallback;
	}

	/**
	 * Subtotal as displayed to the customer (same base WooCommerce uses for free shipping).
	 */
	public function subtotal(): float {
		return $this->cart ? (float) $this->cart->get_displayed_subtotal() : 0.0;
	}
}