<?php

namespace TFGraphics\SmartImport\Search\Data;

final class ProductDataNormalizer
{
    public function text(?string $value): ?string
    {
        if ($value === null) {
            return null;
        }

        // phpcs:ignore WordPress.WP.AlternativeFunctions.strip_tags_strip_tags -- Standalone-test fallback is used only when WordPress is unavailable.
        $stripped = function_exists('wp_strip_all_tags') ? wp_strip_all_tags($value) : \strip_tags($value);
        $decoded = html_entity_decode($stripped, ENT_QUOTES | ENT_HTML5, 'UTF-8');
        $normalized = preg_replace('/\s+/u', ' ', trim($decoded));

        return is_string($normalized) && $normalized !== '' ? $normalized : null;
    }

    public function identifier(?string $value): ?string
    {
        if ($value === null) {
            return null;
        }

        $normalized = strtoupper((string) preg_replace('/[^0-9X]/i', '', $value));

        return in_array(strlen($normalized), [8, 10, 12, 13, 14], true) ? $normalized : null;
    }

    public function isbn13FromIsbn10(?string $isbn10): ?string
    {
        $isbn10 = $this->identifier($isbn10);
        if ($isbn10 === null || strlen($isbn10) !== 10) {
            return null;
        }

        $base = '978' . substr($isbn10, 0, 9);
        $sum = 0;
        for ($index = 0; $index < 12; $index++) {
            $sum += (int) $base[$index] * ($index % 2 === 0 ? 1 : 3);
        }

        return $base . ((10 - ($sum % 10)) % 10);
    }

    public function isbn10FromIsbn13(?string $isbn13): ?string
    {
        $isbn13 = $this->identifier($isbn13);
        if ($isbn13 === null || strlen($isbn13) !== 13 || ! str_starts_with($isbn13, '978')) {
            return null;
        }

        $base = substr($isbn13, 3, 9);
        $sum = 0;
        for ($index = 0; $index < 9; $index++) {
            $sum += (10 - $index) * (int) $base[$index];
        }
        $check = (11 - ($sum % 11)) % 11;

        return $base . ($check === 10 ? 'X' : (string) $check);
    }

    public function language(?string $value): ?string
    {
        $value = $this->text($value);
        if ($value === null) {
            return null;
        }

        $languages = [
            'english' => 'en', 'eng' => 'en',
            'italian' => 'it', 'italiano' => 'it', 'ita' => 'it',
            'french' => 'fr', 'français' => 'fr', 'fre' => 'fr', 'fra' => 'fr',
            'german' => 'de', 'deutsch' => 'de', 'ger' => 'de', 'deu' => 'de',
            'spanish' => 'es', 'español' => 'es', 'spa' => 'es',
        ];
        $key = strtolower($value);

        return $languages[$key] ?? strtolower(substr($value, 0, 2));
    }

    public function publicationDate(?string $value): ?string
    {
        $value = $this->text($value);
        if ($value === null) {
            return null;
        }
        if (preg_match('/^(\d{4})(?:[-\/.](\d{1,2}))?(?:[-\/.](\d{1,2}))?/', $value, $matches) === 1) {
            $year = $matches[1];
            if (! isset($matches[2]) || $matches[2] === '') {
                return $year;
            }
            $month = str_pad($matches[2], 2, '0', STR_PAD_LEFT);
            if (! isset($matches[3]) || $matches[3] === '') {
                return $year . '-' . $month;
            }

            return $year . '-' . $month . '-' . str_pad($matches[3], 2, '0', STR_PAD_LEFT);
        }

        $timestamp = strtotime($value);

        return $timestamp !== false ? gmdate('Y-m-d', $timestamp) : $value;
    }

    public function name(?string $value): ?string
    {
        $value = $this->text($value);

        return $value !== null ? preg_replace('/\s*,\s*/u', ', ', $value) : null;
    }

    public function list(string|array|null $value): array
    {
        $inputs = is_array($value) ? $value : [$value];
        $normalized = [];
        foreach ($inputs as $input) {
            foreach (preg_split('/[,;|]+/u', is_scalar($input) ? (string) $input : '') ?: [] as $item) {
                $text = $this->name($item);
                if ($text === null) {
                    continue;
                }
                $key = strtolower($text);
                if (! isset($normalized[$key])) {
                    $normalized[$key] = $text;
                }
            }
        }

        return array_values($normalized);
    }

    public function imageUrl(?string $value): ?string
    {
        $value = $this->text($value);
        if ($value === null || filter_var($value, FILTER_VALIDATE_URL) === false
            || preg_match('/(?:placeholder|no[-_]?image|spacer|transparent)[^\/]*\.(?:gif|png|jpe?g|webp)(?:\?|$)/i', $value) === 1) {
            return null;
        }

        return str_starts_with($value, 'http://') ? 'https://' . substr($value, 7) : $value;
    }
}