import os
import re
import sys

def add_alt_text_to_images(directory):
    md_files = [f for f in os.listdir(directory) if f.endswith((".md", ".mdx"))]
    image_pattern = re.compile(r'!\[([^\]]*)\]\(([^\)]+)\)')

    for md_file in md_files:
        md_path = os.path.join(directory, md_file)
        with open(md_path, "r", encoding="utf-8") as file:
            content = file.read()

        def replace_alt(match):
            alt_text, image_path = match.groups()
            if alt_text.strip():
                return match.group(0)

            image_name = os.path.basename(image_path)
            alt_text = os.path.splitext(image_name)[0].replace("_", " ").replace("-", " ")
            return f'![{alt_text}]({image_path})'

        new_content = image_pattern.sub(replace_alt, content)

        with open(md_path, "w", encoding="utf-8") as file:
            file.write(new_content)

        print(f"Processed: {md_file}")

if __name__ == "__main__":
    if len(sys.argv) != 2:
        print("Usage: python script.py <directory>")
        sys.exit(1)

    directory = sys.argv[1]
    if not os.path.isdir(directory):
        print("Error: Directory does not exist.")
        sys.exit(1)

    add_alt_text_to_images(directory)