<?php
/**
 * Payment method step.
 *
 * @package Bookline
 */

declare( strict_types=1 );

namespace Bookline\Domain\Steps\Core;

use Bookline\Domain\Steps\BookingSession;
use Bookline\Domain\Steps\Payment\PaymentStepRuleSet;
use Bookline\Domain\Steps\StepDescriptor;
use Bookline\Domain\Steps\ValidationResult;

/**
 * Pay in full / deposit / on site — skip per PaymentStepRuleSet.
 *
 * @since 0.1.0
 */
final class PaymentStep extends AbstractStep {

	/**
	 * Constructor.
	 *
	 * @param PaymentStepRuleSet $rules Payment visibility rules.
	 */
	public function __construct(
		private readonly PaymentStepRuleSet $rules,
	) {}

	/**
	 * Step name.
	 */
	public function name(): string {
		return 'payment';
	}

	/**
	 * Progress label.
	 */
	public function label(): string {
		return 'Payment';
	}

	/**
	 * Front-end component key.
	 */
	protected function component(): string {
		return 'payment';
	}

	/**
	 * Whether the step should be skipped.
	 *
	 * @param BookingSession $session Session.
	 */
	public function should_skip( BookingSession $session ): bool {
		return $this->rules->should_skip( $session );
	}

	/**
	 * Build the step descriptor.
	 *
	 * @param BookingSession $session Session.
	 */
	public function descriptor( BookingSession $session ): StepDescriptor {
		return $this->build_descriptor(
			$session,
			[
				'total_minor' => $session->total_minor(),
				'currency'    => $session->totals()['currency'] ?? 'GBP',
				'decision'    => $this->rules->decide( $session )->value,
			],
			[
				[
					'key'      => 'payment_method',
					'type'     => 'string',
					'required' => true,
				],
			]
		);
	}

	/**
	 * Validate submitted input.
	 *
	 * @param BookingSession       $session Session.
	 * @param array<string, mixed> $input   Payload.
	 */
	public function validate( BookingSession $session, array $input ): ValidationResult {
		if ( $this->should_skip( $session ) ) {
			return ValidationResult::ok();
		}
		$method = $this->string_value( $input, 'payment_method' );
		if ( null === $method ) {
			return ValidationResult::invalid( [ 'payment_method' => 'Please choose a payment method.' ] );
		}
		$allowed = [ 'card', 'deposit', 'on_site' ];
		if ( ! in_array( $method, $allowed, true ) ) {
			return ValidationResult::invalid( [ 'payment_method' => 'That payment method is not available.' ] );
		}
		return ValidationResult::ok();
	}

	/**
	 * Apply validated input.
	 *
	 * @param BookingSession       $session Session.
	 * @param array<string, mixed> $input   Payload.
	 */
	public function apply( BookingSession $session, array $input ): BookingSession {
		$method = $this->string_value( $input, 'payment_method' ) ?? 'on_site';
		$totals = $session->totals();
		$totals['payment_method'] = $method;
		return $session->with_totals( $totals );
	}
}