<?php

declare(strict_types=1);

namespace TFGraphics\SmartImport\Domain;

final class IdentifierValidator
{
    private const LENGTHS = [
        DomainIdentifier::ISBN10 => [10],
        DomainIdentifier::ISBN13 => [13],
        DomainIdentifier::EAN8 => [8],
        DomainIdentifier::EAN13 => [13],
        DomainIdentifier::UPC_A => [12],
        DomainIdentifier::UPC_E => [8],
        DomainIdentifier::GTIN => [14],
        DomainIdentifier::ISSN => [8],
        DomainIdentifier::ISMN => [13],
        DomainIdentifier::ASIN => [10],
        DomainIdentifier::JAN => [13],
        DomainIdentifier::AIC6 => [6],
        DomainIdentifier::AIC9 => [9],
    ];

    private IdentifierChecksum $checksum;

    public function __construct(?IdentifierChecksum $checksum = null)
    {
        $this->checksum = $checksum ?? new IdentifierChecksum();
    }

    public function validate(string $identifierType, string $normalizedValue): array
    {
        $notes = [];
        $expectedLengths = self::LENGTHS[$identifierType] ?? [];

        if ($expectedLengths !== [] && ! in_array(strlen($normalizedValue), $expectedLengths, true)) {
            $notes[] = 'Length mismatch: expected ' . implode(' or ', $expectedLengths) . ' characters.';

            return ['checksum_valid' => null, 'notes' => $notes];
        }

        if ($identifierType === DomainIdentifier::ASIN && preg_match('/^[A-Z0-9]{10}$/', $normalizedValue) !== 1) {
            $notes[] = 'ASIN contains invalid characters.';

            return ['checksum_valid' => null, 'notes' => $notes];
        }

        $checksumValid = $this->checksum->validate($identifierType, $normalizedValue);
        if ($checksumValid === false) {
            $notes[] = 'Checksum invalid.';
        } elseif ($checksumValid === true) {
            $notes[] = 'Checksum valid.';
        } else {
            $notes[] = 'Checksum not defined for this identifier family.';
        }

        return ['checksum_valid' => $checksumValid, 'notes' => $notes];
    }
}