rich_argparse optional dependency

modules/argumentparser.py

@@ -2,7 +2,14 @@ from dataclasses import dataclass
 from typing import List, Optional
 import os
 import argparse
-from rich_argparse import RichHelpFormatter, HelpPreviewAction
+
+try:
+    from rich_argparse import RichHelpFormatter, HelpPreviewAction
+
+    RICH = True
+except ModuleNotFoundError:
+    pass
+
 
 from modules.logger import logger
 
@@ -100,7 +107,10 @@ def parse_arguments(version: str) -> Args:
         An instance of the Args class containing the parsed arguments.
     """
     # fmt: off
+    if RICH:
         parser = argparse.ArgumentParser(description="Generate HTML files for a static image hosting website.", formatter_class=RichHelpFormatter)
+    else:
+        parser = argparse.ArgumentParser(description="Generate HTML files for a static image hosting website.")
     parser.add_argument("-a", "--author-name", help="Name of the author of the images.", default=DEFAULT_AUTHOR, type=str, dest="author_name", metavar="AUTHOR")
     parser.add_argument("-e", "--file-extensions", help="File extensions to include (can be specified multiple times).", action="append", dest="file_extensions", metavar="EXTENSION")
     parser.add_argument("-l", "--license-type", help="Specify the license type for the images.", choices=["cc-zero", "cc-by", "cc-by-sa", "cc-by-nd", "cc-by-nc", "cc-by-nc-sa", "cc-by-nc-nd"], default=None, dest="license_type", metavar="LICENSE")
@@ -110,6 +120,7 @@ def parse_arguments(version: str) -> Args:
     parser.add_argument("-t", "--site-title", help="Title of the image hosting site.", required=True, type=str, dest="site_title", metavar="TITLE")
     parser.add_argument("-w", "--web-root-url", help="Base URL of the web root for the image hosting site.", required=True, type=str, dest="web_root_url", metavar="URL")
     parser.add_argument("--exclude-folder", help="Folders to exclude from processing, globs supported (can be specified multiple times).", action="append", dest="exclude_folders", metavar="FOLDER")
+    if RICH:
         parser.add_argument("--generate-help-preview", action=HelpPreviewAction, path="help.svg", )
     parser.add_argument("--ignore-other-files", help="Ignore files that do not match the specified extensions.", action="store_true", default=False, dest="ignore_other_files")
     parser.add_argument("--regenerate-thumbnails", help="Regenerate thumbnails even if they already exist.", action="store_true", default=False, dest="regenerate_thumbnails")