Expose the credit card merchant as a separate field

Tests/Unit/Segment/DIKKUTest.php

@@ -174,6 +174,10 @@ public function testMapsToModel()
         $this->assertEquals('2026-07-18', $domestic->getBookingDate()->format('Y-m-d'));
         $this->assertEquals('2026-07-17', $domestic->getValutaDate()->format('Y-m-d'));
         $this->assertEquals('EXAMPLE SHOP BERLIN 555500******2233', $domestic->getPurpose());
+        // getMerchant() returns just the first line, without the location and masked card number that
+        // getPurpose() carries, so the same merchant yields a stable name across bookings.
+        $this->assertEquals('EXAMPLE SHOP', $domestic->getMerchant());
+        $this->assertEquals(['EXAMPLE SHOP', 'BERLIN 555500******2233'], $domestic->getPurposeLines());
         $this->assertEquals('5411', $domestic->getMerchantCategoryCode());
         // No conversion took place, so no original amount is reported.
         $this->assertNull($domestic->getOriginalAmount());
@@ -189,6 +193,8 @@ public function testMapsToModel()
         $this->assertEquals(1000.0, $settlement->getAmount());
         $this->assertEquals(CreditCardTransaction::CD_CREDIT, $settlement->getCreditDebit());
         $this->assertNull($settlement->getMerchantCategoryCode());
+        // A booking without a real merchant still exposes its first line via getMerchant().
+        $this->assertEquals('Ausgleich Kreditkartenabrechnung', $settlement->getMerchant());
     }
 
     public function testEmptyStatement()

src/Model/CreditCardStatement/CreditCardTransaction.php

@@ -29,6 +29,12 @@ class CreditCardTransaction
     /** The exchange rate applied, or null if no conversion took place. */
     protected ?float $exchangeRate = null;
     protected string $purpose = '';
+    /**
+     * The individual Verwendungszweck lines, in order, non-empty only. {@link $purpose} is these
+     * joined by spaces. Usually the first line is the merchant name and the second the merchant
+     * location followed by the masked card number.
+     */
+    protected array $purposeLines = [];
     protected ?string $reference = null;
     /** ISO 18245 merchant category code, e.g. 5411 for grocery stores. Null if the booking has no merchant. */
     protected ?string $merchantCategoryCode = null;
@@ -110,6 +116,41 @@ public function setPurpose(string $purpose): static
         return $this;
     }
 
+    /**
+     * @return string[] The individual Verwendungszweck lines, in order, non-empty only. Usually the
+     *     first line is the merchant name and the second the merchant location followed by the masked
+     *     card number. {@link getPurpose()} returns these joined by spaces.
+     */
+    public function getPurposeLines(): array
+    {
+        return $this->purposeLines;
+    }
+
+    /**
+     * @param string[] $purposeLines
+     */
+    public function setPurposeLines(array $purposeLines): static
+    {
+        $this->purposeLines = $purposeLines;
+        return $this;
+    }
+
+    /**
+     * The merchant name, taken from the first Verwendungszweck line. Prefer this over
+     * {@link getPurpose()} when you need a stable counterparty name (e.g. to name an expense account),
+     * because the full purpose also contains the location and the masked card number, which vary
+     * between bookings of the same merchant.
+     *
+     * For bookings without a merchant, such as the monthly settlement, this returns whatever
+     * descriptive text the bank placed in the first line (e.g. "Ausgleich Kreditkartenabrechnung").
+     *
+     * @return string|null Null only if the record carries no Verwendungszweck at all.
+     */
+    public function getMerchant(): ?string
+    {
+        return $this->purposeLines[0] ?? null;
+    }
+
     public function getReference(): ?string
     {
         return $this->reference;
@@ -193,7 +234,8 @@ public static function fromSegment(Kreditkartenumsatz $umsatz): CreditCardTransa
             $result->exchangeRate = $umsatz->umrechnungskurs;
         }
 
-        $result->purpose = trim(implode(' ', $umsatz->getVerwendungszweckLines()));
+        $result->purposeLines = $umsatz->getVerwendungszweckLines();
+        $result->purpose = trim(implode(' ', $result->purposeLines));
         $result->reference = $umsatz->referenz;
         $result->merchantCategoryCode = $umsatz->branchenschluessel;
         return $result;