sfp_api_laravel_serprati/app/Imports/AssociadoImport.php

<?php

namespace App\Imports;

use Carbon\Carbon;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\Log;
use Maatwebsite\Excel\Concerns\ToCollection;
use Maatwebsite\Excel\Concerns\WithCalculatedFormulas;
use PhpOffice\PhpSpreadsheet\Shared\Date;
use Throwable;

class AssociadoImport implements ToCollection, WithCalculatedFormulas
{
    public Collection $rows;

    public function collection(Collection $rows): void
    {
        $this->rows = $rows->skip(1)->values()->filter(function ($row) {
            return !empty(trim((string) ($row[0] ?? '')))
                && !empty(trim((string) ($row[1] ?? '')))
                && !empty(trim((string) ($row[2] ?? '')));
        })->map(function ($row) {
            $registration = trim((string) $row[0]);

            return [
                'registration'   => $registration,
                'name'           => trim((string) $row[1]),
                'admission_date' => $this->resolveAdmissionDate($row[2] ?? null, $registration),
            ];
        })->values();
    }

    private function resolveAdmissionDate($rawValue, string $registration): ?string
    {
        try {
            if (is_int($rawValue) || is_float($rawValue)) {
                return Date::excelToDateTimeObject($rawValue)->format('Y-m-d');
            }

            if (is_string($rawValue) && is_numeric($rawValue)) {
                return Date::excelToDateTimeObject((float) $rawValue)->format('Y-m-d');
            }

            if (is_string($rawValue) && $rawValue !== '' && $rawValue[0] !== '=') {
                return Carbon::parse($rawValue)->format('Y-m-d');
            }
        } catch (Throwable $e) {
            // falls through to warning below
        }

        Log::warning('AssociadoImport: could not resolve admission_date, leaving null', [
            'registration' => $registration,
            'raw_value'    => is_scalar($rawValue) ? $rawValue : json_encode($rawValue),
        ]);

        return null;
    }
}