[IMP] account_statement_import_sheet_file: Use parse_header and fine-tune the UI

Before this commit, the parse_header function was unused. It is now utilized to reduce redundant code and improve maintainability.
Additionally, UI adjustments have been made for better usability and clarity.

account_statement_import_sheet_file/models/account_statement_import_sheet_parser.py

@@ -39,22 +39,22 @@ class AccountStatementImportSheetParser(models.TransientModel):
     _description = "Bank Statement Import Sheet Parser"
 
     @api.model
-    def parse_header(self, data_file, encoding, csv_options, header_lines_skip_count=0):
-        try:
-            workbook = xlrd.open_workbook(
-                file_contents=data_file,
-                encoding_override=encoding if encoding else None,
-            )
-            sheet = workbook.sheet_by_index(0)
-            values = sheet.row_values(header_lines_skip_count - 1)
-            return [str(value) for value in values]
-        except xlrd.XLRDError:
-            _logger.error("Pass this method")
-
-        data = StringIO(data_file.decode(encoding or "utf-8"))
-        csv_data = reader(data, **csv_options)
-        csv_data_lst = list(csv_data)
-        header = [value.strip() for value in csv_data_lst[header_lines_skip_count - 1]]
+    def parse_header(self, csv_or_xlsx, mapping):
+        if mapping.no_header:
+            return []
+        header_line = mapping.header_lines_skip_count
+        # prevent negative indexes
+        if header_line > 0:
+            header_line -= 1
+        if isinstance(csv_or_xlsx, tuple):
+            header = [
+                str(value).strip() for value in csv_or_xlsx[1].row_values(header_line)
+            ]
+        else:
+            [next(csv_or_xlsx) for _i in range(header_line)]
+            header = [value.strip() for value in next(csv_or_xlsx)]
+        if mapping.offset_column:
+            header = header[mapping.offset_column :]
         return header
 
     @api.model
@@ -177,22 +177,7 @@ class AccountStatementImportSheetParser(models.TransientModel):
                     ) from None
                 decoded_file = data_file.decode(detected_encoding)
             csv_or_xlsx = reader(StringIO(decoded_file), **csv_options)
-        header = False
-        if not mapping.no_header:
-            header_line = mapping.header_lines_skip_count
-            # prevent negative indexes
-            if header_line > 0:
-                header_line -= 1
-            if isinstance(csv_or_xlsx, tuple):
-                header = [
-                    str(value).strip()
-                    for value in csv_or_xlsx[1].row_values(header_line)
-                ]
-            else:
-                [next(csv_or_xlsx) for _i in range(header_line)]
-                header = [value.strip() for value in next(csv_or_xlsx)]
-            if mapping.offset_column:
-                header = header[mapping.offset_column :]
+        header = self.parse_header(csv_or_xlsx, mapping)
 
         # NOTE no seria necesario debit_column y credit_column ya que tenemos los
         # respectivos campos related

account_statement_import_sheet_file/views/account_statement_import_sheet_mapping.xml

@@ -44,6 +44,7 @@
                             <div
                                 class="alert alert-warning"
                                 role="alert"
+                                colspan="2"
                                 attrs="{'invisible': [('no_header', '=', False)]}"
                             >
                                 <span