Enhance readFiles method to validate CSV row structure and return error response for insufficient columns

app/Http/Controllers/SapFileController.php

@@ -177,31 +177,37 @@ class SapFileController extends Controller
         //     'status' => 'SUCCESS',
         //     'rows_imported' => count($rows),
         // ]);
-        // Remove header row
-        $headerLine = array_shift($lines);
+
 
         // Prepare arrays
         $serialNumbers = [];
         $remainingRows = [];
 
-        foreach ($lines as $line) {
-            $values = str_getcsv($line);
-
-            // Serial number is 6th column (index 5)
-            $serialNumbers[] = $values[5] ?? null;
-
-            // Remove the serial number column and keep remaining
-            $remainingRow = $values;
-            unset($remainingRow[5]);
-            $remainingRow = array_values($remainingRow); // reindex array
-            $remainingRows[] = $remainingRow;
-        }
+       foreach ($lines as $line) {
+    $values = str_getcsv($line);
 
+    // Debug: make sure CSV split is correct
+    if (count($values) < 6) {
         return response()->json([
-            'status' => 'SUCCESS',
-            'serial_numbers' => $serialNumbers,
-            'remaining_rows' => $remainingRows,
-        ]);
+            'status' => 'ERROR',
+            'message' => 'CSV row has fewer than 6 columns',
+            'line' => $line
+        ], 400);
+    }
+
+    $serialNumbers[] = $values[5] ?? null;
+
+    $remainingRow = $values;
+    unset($remainingRow[5]);
+    $remainingRow = array_values($remainingRow); // reindex
+    $remainingRows[] = $remainingRow;
+}
+
+return response()->json([
+    'status' => 'SUCCESS',
+    'serial_numbers' => $serialNumbers,
+    'remaining_rows_sample' => array_slice($remainingRows, 0, 5), // just first 5 for debug
+]);
     }