<?php

namespace Tests\Unit;

use App\Support\CreditorId;
use PHPUnit\Framework\TestCase;

class CreditorIdTest extends TestCase
{
    public function test_normalizes_spaces_and_case(): void
    {
        $this->assertSame('DE98ZZZ09999999999', CreditorId::normalize(' de98 zzz 0999 9999 999 '));
    }

    public function test_accepts_the_bundesbank_test_id(): void
    {
        $this->assertTrue(CreditorId::isValid('DE98ZZZ09999999999'));
        $this->assertTrue(CreditorId::isValid('de98 zzz 09999999999'));
    }

    public function test_business_code_does_not_affect_the_check_digit(): void
    {
        // Die Geschäftsbereichskennung (Stellen 5-7) wählt der Gläubiger selbst -- die Prüfziffer bleibt.
        $this->assertTrue(CreditorId::isValid('DE98ABC09999999999'));
    }

    public function test_rejects_a_wrong_check_digit(): void
    {
        $this->assertFalse(CreditorId::isValid('DE97ZZZ09999999999'));
        $this->assertFalse(CreditorId::isValid('DE98ZZZ09999999998'));
    }

    public function test_rejects_a_wrong_german_length(): void
    {
        $this->assertFalse(CreditorId::isValid('DE98ZZZ0999999999'));
        $this->assertFalse(CreditorId::isValid('DE98ZZZ099999999990'));
    }

    public function test_rejects_malformed_input(): void
    {
        $this->assertFalse(CreditorId::isValid(''));
        $this->assertFalse(CreditorId::isValid('DE02120300000000202051')); // eine IBAN
        $this->assertFalse(CreditorId::isValid('DEXXZZZ09999999999'));
    }
}