Added filter to update Level 3 data.

changelog/try-gc-as-discount

@@ -0,0 +1,4 @@
+Significance: patch
+Type: add
+
+Added filter to enable updating Level 3 data based on order data.

src/Internal/Service/Level3Service.php

@@ -85,14 +85,6 @@ public function get_data_from_order( int $order_id ): array {
 		};
 		$items_to_send = array_map( $process_item, $order_items );
 
-		if ( count( $items_to_send ) > 200 ) {
-			// If more than 200 items are present, bundle the last ones in a single item.
-			$items_to_send = array_merge(
-				array_slice( $items_to_send, 0, 199 ),
-				[ $this->bundle_level3_data_from_items( array_slice( $items_to_send, 200 ) ) ]
-			);
-		}
-
 		$level3_data = [
 			'merchant_reference' => (string) $order->get_id(), // An alphanumeric string of up to  characters in length. This unique value is assigned by the merchant to identify the order. Also known as an “Order ID”.
 			'customer_reference' => (string) $order->get_id(),
@@ -112,6 +104,29 @@ public function get_data_from_order( int $order_id ): array {
 			$level3_data['shipping_from_zip'] = $store_postcode;
 		}
 
+		/**
+		 * Filters the Level 3 data based on order.
+		 *
+		 * Example usage: Enables updating the discount based on the products in the order,
+		 * if any of the products are gift cards.
+		 *
+		 * @since 8.0.0
+		 *
+		 * @param array $level3_data Precalculated Level 3 data based on order.
+		 * @param WC_Order $order    The order object.
+		 */
+		$level3_data = apply_filters( 'wcpay_payment_request_level3_data', $level3_data, $order );
+
+		if ( count( $level3_data['line_items'] ) > 200 ) {
+			// If more than 200 items are present, bundle the last ones in a single item.
+			$items_to_send = array_merge(
+				array_slice( $level3_data['line_items'], 0, 199 ),
+				[ $this->bundle_level3_data_from_items( array_slice( $level3_data['line_items'], 199 ) ) ]
+			);
+
+			$level3_data['line_items'] = $items_to_send;
+		}
+
 		return $level3_data;
 	}
 

tests/unit/src/Internal/Service/Level3ServiceTest.php

@@ -164,7 +164,7 @@ protected function mock_level_3_order(
 
 		if ( $basket_size > 1 ) {
 			// Keep the formely created item/fee and add duplicated items to the basket.
-			$mock_items = array_merge( $mock_items, array_fill( 0, $basket_size - 1, $mock_items[0] ) );
+			$mock_items = array_merge( $mock_items, array_fill( 0, $basket_size - count( $mock_items ), $mock_items[0] ) );
 		}
 
 		// Setup the order.