#!/usr/bin/env python3

import os
import argparse


def main():
    parser = argparse.ArgumentParser(description='Retain specified number of files in a directory sorted by name, delete others.')
    parser.add_argument('directory', type=str, help='Path to target directory')
    parser.add_argument('--keep', type=int, default=2, 
                        help='Number of files to retain (default: 2)')
    args = parser.parse_args()

    # Validate arguments
    if args.keep < 0:
        parser.error("--keep value cannot be negative")

    if not os.path.isdir(args.directory):
        parser.error(f"Directory not found: {args.directory}")

    # Get list of files (exclude subdirectories)
    files = []
    with os.scandir(args.directory) as entries:
        for entry in entries:
            if entry.is_file():
                files.append(entry.name)

    # Sort files alphabetically
    sorted_files = sorted(files)
    
    # Identify files to delete
    to_delete = sorted_files[:-args.keep] if args.keep > 0 else sorted_files.copy()
    
    # Delete files and print results
    for filename in to_delete:
        filepath = os.path.join(args.directory, filename)
        try:
            os.remove(filepath)
            print(f"Deleted: {filename}")
        except Exception as e:
            print(f"Error deleting {filename}: {str(e)}")


if __name__ == "__main__":
    main()