Config: Alter YAML generator function

These changes fix the amount and order of newlines to look pleasing
for the user. However, the changes used in here are kind of hacky
and need a proper fix that can contain the same level of efficiency.

Signed-off-by: kingbri <bdashore3@proton.me>

common/config_models.py

@@ -1,6 +1,8 @@
-from pydantic import AliasChoices, BaseModel, ConfigDict, Field, PrivateAttr
-from typing import List, Literal, Optional, Union
+from inspect import getdoc
 from pathlib import Path
+from pydantic import AliasChoices, BaseModel, ConfigDict, Field, PrivateAttr
+from textwrap import dedent
+from typing import List, Literal, Optional, Union
 
 from pydantic_core import PydanticUndefined
 
@@ -385,6 +387,7 @@ class TabbyConfigModel(BaseModel):
     model_config = ConfigDict(validate_assignment=True, protected_namespaces=())
 
 
+# TODO: Possibly switch to ruamel.yaml for a more native implementation
 def generate_config_file(
     model: BaseConfigModel = None,
     filename: str = "config_sample.yml",
@@ -392,23 +395,51 @@ def generate_config_file(
 ) -> None:
     """Creates a config.yml file from Pydantic models."""
 
-    schema = model if model else TabbyConfigModel()
-    yaml = ""
+    # Add a preamble
+    yaml = dedent("""
+    # Sample YAML file for configuration.
+    # Comment and uncomment values as needed.
+    # Every value has a default within the application.
+    # This file serves to be a drop in for config.yml
 
+    # Unless specified in the comments, DO NOT put these options in quotes!
+    # You can use https://www.yamllint.com/ if you want to check your YAML formatting.\n
+    """)
+
+    schema = model if model else TabbyConfigModel()
+
+    # TODO: Make the disordered iteration look cleaner
+    iter_once = False
     for field, field_data in schema.model_fields.items():
         subfield_model = field_data.default_factory()
+
         if not subfield_model._metadata.include_in_config:
             continue
 
-        yaml += f"# {subfield_model.__doc__}\n"
+        # Since the list is out of order with the length
+        # Add newlines from the beginning once one iteration finishes
+        # This is a sanity check for formatting
+        if iter_once:
+            yaml += "\n"
+        else:
+            iter_once = True
+
+        yaml += f"# {getdoc(subfield_model)}\n"
         yaml += f"{field}:\n"
+
+        sub_iter_once = False
         for subfield, subfield_data in subfield_model.model_fields.items():
+            # Same logic as iter_once
+            if sub_iter_once:
+                yaml += "\n"
+            else:
+                sub_iter_once = True
+
             value = subfield_data.default
             value = value if value is not None else ""
             value = value if value is not PydanticUndefined else ""
             yaml += f"{' ' * indentation}# {subfield_data.description}\n"
             yaml += f"{' ' * indentation}{subfield}: {value}\n"
-        yaml += "\n"
 
     with open(filename, "w") as f:
         f.write(yaml)