Bulk file renamer

Bulk_renamer.py

#  Python script for bulk renaming files in a specified directory
# How to use:
# python bulk_renamer.py /path/to/directory new_name_prefix --extension .txt --start 1
# Renames .txt files as new_name_prefix1.txt, new_name_prefix2.txt, etc.
# If --extension is omitted, it renames all files.
# Modify the prefix to customize filenames.

import os
import argparse

def bulk_rename(directory, prefix, extension=None, start_number=1):
    """Renames files in a given directory with a specified prefix and optional extension filter."""
    
    files = sorted(os.listdir(directory))  # Sort to maintain order
    count = start_number
    
    for file in files:
        file_path = os.path.join(directory, file)
        
        if not os.path.isfile(file_path):
            continue  # Skip directories
        
        file_ext = os.path.splitext(file)[1]
        
        if extension and file_ext.lower() != extension.lower():
            continue  # Skip files not matching extension
        
        new_name = f"{prefix}{count}{file_ext}"
        new_path = os.path.join(directory, new_name)
        
        os.rename(file_path, new_path)
        print(f"Renamed: {file} -> {new_name}")
        
        count += 1

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="Bulk rename files in a directory.")
    parser.add_argument("directory", type=str, help="Path to the directory containing files.")
    parser.add_argument("prefix", type=str, help="New filename prefix.")
    parser.add_argument("--extension", type=str, help="Only rename files with this extension (e.g., .txt).", default=None)
    parser.add_argument("--start", type=int, help="Starting number for renaming.", default=1)
    
    args = parser.parse_args()
    bulk_rename(args.directory, args.prefix, args.extension, args.start)