<?php
/**
 * Date rule.
 *
 * @package FormPilot
 * @since   1.0.0
 */

declare( strict_types = 1 );

namespace FormPilot\Validation\Rules;

use FormPilot\Contracts\ValidationRule;
use FormPilot\Fields\FieldTypes;
use FormPilot\Models\Field;
use FormPilot\Validation\ValidationError;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Checks that a date field holds a real calendar date.
 *
 * The browser sends `Y-m-d` from a date input. A date that parses but does not
 * exist, such as the 31st of February, is refused here.
 *
 * @since 1.0.0
 */
final class DateRule implements ValidationRule {

	/**
	 * Determines whether this rule applies to a field.
	 *
	 * @param Field $field Field being validated.
	 */
	public function supports( Field $field ): bool {
		return FieldTypes::DATE === $field->type();
	}

	/**
	 * Checks the date.
	 *
	 * @param Field $field Field being validated.
	 * @param mixed $value Sanitised value.
	 *
	 * @return ValidationError|null The failure, or null when the value passes.
	 */
	public function validate( Field $field, mixed $value ): ?ValidationError {
		$date = (string) $value;

		/*
		 * Exactly YYYY-MM-DD, which is what a date input sends. Splitting on "-" and
		 * casting each piece to int accepted `2024-1-1` and `2025-01-01 junk…`, and
		 * the min/max checks below compare strings, which only works when every date
		 * has the same zero-padded shape - so `2024-1-1` slipped under a minimum of
		 * 2024-06-01.
		 */
		$valid = 1 === preg_match( '/^(\d{4})-(\d{2})-(\d{2})$/', $date, $parts )
			&& wp_checkdate( (int) $parts[2], (int) $parts[3], (int) $parts[1], $date );

		if ( ! $valid ) {
			return new ValidationError(
				'',
				'invalid_date',
				__( 'Please enter a valid date.', 'devplugins-custom-form-builder' )
			);
		}

		$min = (string) $field->setting( 'min_date', '' );
		$max = (string) $field->setting( 'max_date', '' );

		if ( '' !== $min && $date < $min ) {
			return new ValidationError(
				'',
				'date_too_early',
				sprintf(
					/* translators: %s: Earliest accepted date. */
					__( 'Please choose a date on or after %s.', 'devplugins-custom-form-builder' ),
					$min
				),
				array( 'min' => $min )
			);
		}

		if ( '' !== $max && $date > $max ) {
			return new ValidationError(
				'',
				'date_too_late',
				sprintf(
					/* translators: %s: Latest accepted date. */
					__( 'Please choose a date on or before %s.', 'devplugins-custom-form-builder' ),
					$max
				),
				array( 'max' => $max )
			);
		}

		return null;
	}
}