<?php
/**
 * Selection store (WooCommerce session).
 *
 * @package Extrova
 */

declare( strict_types=1 );

namespace Extrova\Core;

defined( 'ABSPATH' ) || exit;

/**
 * Single source of truth for what the customer selected. Works with the classic session
 * cookie and with the Store API Cart-Token session alike.
 *
 * @since 1.0.0
 */
final class SelectionStore {

	public const SESSION_KEY = 'extrova_selections';

	/**
	 * WooCommerce session, if any.
	 */
	private function session(): ?\WC_Session {
		if ( ! function_exists( 'WC' ) ) {
			return null;
		}
		$session = WC()->session;
		return $session instanceof \WC_Session ? $session : null;
	}

	/**
	 * All selections keyed by extra id.
	 *
	 * @return array<string, Selection>
	 */
	public function all(): array {
		$session = $this->session();
		if ( ! $session ) {
			return array();
		}
		$raw = $session->get( self::SESSION_KEY, array() );
		if ( ! is_array( $raw ) ) {
			return array();
		}
		$selections = array();
		foreach ( $raw as $extra_id => $data ) {
			if ( is_string( $extra_id ) && is_array( $data ) ) {
				$selections[ $extra_id ] = Selection::from_array( $extra_id, $data );
			}
		}
		return $selections;
	}

	/**
	 * One selection.
	 *
	 * @param string $extra_id Extra id.
	 */
	public function get( string $extra_id ): ?Selection {
		return $this->all()[ $extra_id ] ?? null;
	}

	/**
	 * Replaces every selection.
	 *
	 * @param array<string, Selection> $selections Selections.
	 */
	public function replace( array $selections ): void {
		$session = $this->session();
		if ( ! $session ) {
			return;
		}
		$raw = array();
		foreach ( $selections as $selection ) {
			if ( $selection instanceof Selection ) {
				$raw[ $selection->extra_id ] = $selection->to_array();
			}
		}
		$session->set( self::SESSION_KEY, $raw );
	}

	/**
	 * Clears every selection (cart emptied).
	 */
	public function clear(): void {
		$session = $this->session();
		if ( $session ) {
			$session->set( self::SESSION_KEY, array() );
		}
	}
}