fixed usage help and added -h to command

pdf_sanatizer.py

@@ -37,11 +37,11 @@ number of watermark segments removed.
 This script requires the PyMuPDF (``fitz``) package.
 """
 
+import argparse
 import sys
 import os
 import re
 import getpass
-from typing import Tuple, Optional
 
 import fitz  # type: ignore[import]
 
@@ -162,11 +162,23 @@ def sanitize_pdf(path: str) -> None:
     print(f"Removed {removed} watermark segment(s). Cleaned PDF saved as '{out_path}'.")
 
 
+def build_parser() -> argparse.ArgumentParser:
+    parser = argparse.ArgumentParser(
+        description="Remove SANS-style watermark overlays from the provided PDF. "
+        "Encrypted PDFs are supported and will trigger a password prompt."
+    )
+    parser.add_argument(
+        "input_pdf",
+        metavar="INPUT.pdf",
+        help="Path to the PDF you want sanitized."
+    )
+    return parser
+
+
 def main(argv: list[str]) -> None:
-    if len(argv) != 2:
-        print("Usage: python enhanced_sanitize_pdf.py input.pdf")
-        return
-    sanitize_pdf(argv[1])
+    parser = build_parser()
+    args = parser.parse_args(argv[1:])
+    sanitize_pdf(args.input_pdf)
 
 
 if __name__ == "__main__":