<?php
declare(strict_types=1);

namespace Unsupervised\Schedular\Payment;

/**
 * Resolves the billing method for a student: a per-student override if set,
 * otherwise the studio default — card when Stripe is configured, e-transfer when
 * it is not.
 */
class BillingMethodResolver {

	public const META_METHOD = 'us_payment_method';

	public function __construct( private StudioSettings $settings ) {}

	public function resolve( int $studentId ): string {
		$override = (string) get_user_meta( $studentId, self::META_METHOD, true );
		if ( in_array( $override, Payment::VALID_METHODS, true ) ) {
			return $override;
		}

		return $this->defaultMethod();
	}

	/**
	 * The studio default when a student has no explicit override.
	 */
	public function defaultMethod(): string {
		return $this->settings->isStripeConfigured()
			? Payment::METHOD_CARD
			: Payment::METHOD_ETRANSFER;
	}
}