<?php
/**
 * Computes the amount due now versus later.
 *
 * @package Bookline
 */

declare( strict_types=1 );

namespace Bookline\Domain\Pricing\Modifiers;

use Bookline\Domain\Pricing\Money;
use Bookline\Domain\Pricing\PriceChargeMode;
use Bookline\Domain\Pricing\PriceContext;
use Bookline\Domain\Pricing\PriceModifier;
use Bookline\Domain\Service\DepositType;

/**
 * Priority 70 — deposit / due-now calculation.
 *
 * Returns the amount due now. The calculator snapshots the grand total before this step.
 *
 * @since 0.1.0
 */
final class DepositCalculation implements PriceModifier {

	/**
	 * Priority.
	 *
	 * @since 0.1.0
	 */
	public function priority(): int {
		return 70;
	}

	/**
	 * Return the amount due now for the given grand total.
	 *
	 * @param PriceContext $ctx     Context.
	 * @param Money        $running Grand total after tax.
	 *
	 * @since 0.1.0
	 */
	public function apply( PriceContext $ctx, Money $running ): Money {
		return match ( $ctx->charge_mode() ) {
			PriceChargeMode::Full => $running,
			PriceChargeMode::OnSite => Money::zero( $running->currency() ),
			PriceChargeMode::Deposit => $this->deposit_amount( $ctx, $running ),
		};
	}

	/**
	 * Deposit amount capped at the grand total.
	 *
	 * @param PriceContext $ctx   Context.
	 * @param Money        $total Grand total.
	 *
	 * @since 0.1.0
	 */
	public function deposit_amount( PriceContext $ctx, Money $total ): Money {
		if ( DepositType::None === $ctx->deposit_type() ) {
			return $total;
		}

		if ( DepositType::Percent === $ctx->deposit_type() ) {
			return $total->percent( $ctx->deposit_value() );
		}

		$fixed = new Money( $ctx->deposit_value(), $total->currency() );
		if ( $fixed->amount_minor() > $total->amount_minor() ) {
			return $total;
		}
		return $fixed;
	}
}