Generator numeru referencyjnego

{
  "references": [
    {
      "id": 1,
      "code": "REF-2026-0001",
      "format": "prefix_year_seq",
      "purpose": "Faktura",
      "created_at": "2026-02-10 14:30:00"
    },
    {
      "id": 2,
      "code": "REF-2026-0002",
      "format": "prefix_year_seq",
      "purpose": "",
      "created_at": "2026-02-10 15:45:00"
    },
    {
      "id": 3,
      "code": "INV-202602-0001",
      "format": "prefix_yearmonth_seq",
      "purpose": "Zamówienie",
      "created_at": "2026-02-11 09:00:00"
    }
  ]
}

function generateReferenceNumber(array $existingCodes, string $prefix = 'REF'): string {
    $year = date('Y');
    $pattern = $prefix . '-' . $year . '-';

    // Znajdź najwyższy numer w tym roku
    $maxSeq = 0;
    foreach ($existingCodes as $ref) {
        if (strpos($ref['code'], $pattern) === 0) {
            $seq = (int) substr($ref['code'], strlen($pattern));
            $maxSeq = max($maxSeq, $seq);
        }
    }

    $nextSeq = $maxSeq + 1;
    return $pattern . str_pad($nextSeq, 4, '0', STR_PAD_LEFT);
}

// Wynik: REF-2026-0001, REF-2026-0002, ...

function generateByFormat(array $existingCodes, string $format, string $prefix = 'REF'): string {
    switch ($format) {
        case 'prefix_year_seq':
            // REF-2026-0001
            $pattern = $prefix . '-' . date('Y') . '-';
            break;

        case 'prefix_yearmonth_seq':
            // REF-202602-0001
            $pattern = $prefix . '-' . date('Ym') . '-';
            break;

        case 'year_seq':
            // 2026/0001
            $pattern = date('Y') . '/';
            break;

        case 'prefix_seq':
            // REF-0001
            $pattern = $prefix . '-';
            break;

        default:
            $pattern = $prefix . '-' . date('Y') . '-';
    }

    $maxSeq = findMaxSequence($existingCodes, $pattern);
    $nextSeq = $maxSeq + 1;

    return $pattern . str_pad($nextSeq, 4, '0', STR_PAD_LEFT);
}

function findMaxSequence(array $codes, string $pattern): int {
    $maxSeq = 0;

    foreach ($codes as $ref) {
        $code = $ref['code'];
        if (strpos($code, $pattern) === 0) {
            $seqPart = substr($code, strlen($pattern));
            $seq = (int) preg_replace('/[^0-9]/', '', $seqPart);
            $maxSeq = max($maxSeq, $seq);
        }
    }

    return $maxSeq;
}

function isUnique(array $existingCodes, string $newCode): bool {
    foreach ($existingCodes as $ref) {
        if ($ref['code'] === $newCode) {
            return false;
        }
    }
    return true;
}

function generateUniqueCode(array $existingCodes, string $format, string $prefix): string {
    $attempts = 0;
    $maxAttempts = 100;

    do {
        $code = generateByFormat($existingCodes, $format, $prefix);
        $attempts++;

        if ($attempts >= $maxAttempts) {
            throw new Exception("Nie można wygenerować unikalnego kodu");
        }
    } while (!isUnique($existingCodes, $code));

    return $code;
}

function shouldResetSequence(string $format, array $existingCodes): bool {
    if (empty($existingCodes)) {
        return false;
    }

    $lastRef = end($existingCodes);
    $lastDate = date('Y-m', strtotime($lastRef['created_at']));
    $currentDate = date('Y-m');

    // Resetuj przy zmianie miesiąca dla formatów z miesiącem
    if ($format === 'prefix_yearmonth_seq' && $lastDate !== $currentDate) {
        return true;
    }

    // Resetuj przy zmianie roku dla formatów z rokiem
    $lastYear = date('Y', strtotime($lastRef['created_at']));
    $currentYear = date('Y');

    if (in_array($format, ['prefix_year_seq', 'year_seq']) && $lastYear !== $currentYear) {
        return true;
    }

    return false;
}

function saveReference(array &$references, string $code, string $format, string $purpose = ''): int {
    $newId = empty($references) ? 1 : max(array_column($references, 'id')) + 1;

    $newRef = [
        'id' => $newId,
        'code' => $code,
        'format' => $format,
        'purpose' => trim($purpose),
        'created_at' => date('Y-m-d H:i:s'),
    ];

    $references[] = $newRef;
    return $newId;
}

function copyCode(code) {
    navigator.clipboard.writeText(code).then(() => {
        showNotification('Skopiowano: ' + code);
    }).catch(err => {
        console.error('Błąd kopiowania:', err);
        // Fallback dla starszych przeglądarek
        fallbackCopy(code);
    });
}

function fallbackCopy(text) {
    const textarea = document.createElement('textarea');
    textarea.value = text;
    document.body.appendChild(textarea);
    textarea.select();
    document.execCommand('copy');
    document.body.removeChild(textarea);
    showNotification('Skopiowano: ' + text);
}

function getAvailableFormats(): array {
    return [
        'prefix_year_seq' => [
            'name' => 'PREFIX-RRRR-NNNN',
            'example' => 'REF-2026-0001',
            'description' => 'Prefiks, rok, numer sekwencyjny',
        ],
        'prefix_yearmonth_seq' => [
            'name' => 'PREFIX-RRRRMM-NNNN',
            'example' => 'INV-202602-0001',
            'description' => 'Prefiks, rok i miesiąc, numer (resetuje się co miesiąc)',
        ],
        'year_seq' => [
            'name' => 'RRRR/NNNN',
            'example' => '2026/0001',
            'description' => 'Rok/numer',
        ],
        'prefix_seq' => [
            'name' => 'PREFIX-NNNN',
            'example' => 'DOC-0001',
            'description' => 'Prefiks i numer (bez daty)',
        ],
    ];
}