import os
from huggingface_hub import hf_hub_download

def load_script(file_str: str):
    """
    file_str: something like 'myorg/myrepo/mysubfolder/myscript.py'
    This function downloads the file from the Hugging Face Hub into ./ (current directory).
    """
    try:
        # Split the path by "/"
        parts = file_str.split("/")
        
        if len(parts) < 3:
            raise ValueError(
                f"Invalid file specification '{file_str}'. "
                f"Expected format: 'repo_id/[subfolder]/filename'"
            )
        
        # First two parts form the repo_id (e.g. 'myorg/myrepo')
        repo_id = "/".join(parts[:2])
        
        # Last part is the actual filename (e.g. 'myscript.py')
        filename = parts[-1]
        
        # Anything between the second and last parts is a subfolder path
        subfolder = None
        if len(parts) > 3:
            subfolder = "/".join(parts[2:-1])

        # Retrieve HF token from environment
        hf_token = os.getenv("HF_TOKEN", None)

        # Download the file into current directory "."
        file_path = hf_hub_download(
            repo_id=repo_id,
            filename=filename,
            subfolder=subfolder,
            token=hf_token,
            local_dir="."  # Download into current directory
        )
        
        print(f"Downloaded {filename} from {repo_id} to {file_path}")
        return file_path

    except Exception as e:
        print(f"Error downloading the script '{file_str}': {e}")
        return None


def load_scripts():
    """
    1. Get the path of the 'FILE_LIST' file from the environment variable FILE_LIST.
    2. Download that file list using load_script().
    3. Read its lines, and each line is another file to be downloaded using load_script().
    4. After all lines are downloaded, execute the last file.
    """
    file_list = os.getenv("FILE_LIST", "").strip()
    if not file_list:
        print("No FILE_LIST environment variable set. Nothing to download.")
        return

    # Step 1: Download the file list itself
    file_list_path = load_script(file_list)
    if not file_list_path or not os.path.exists(file_list_path):
        print(f"Could not download or find file list: {file_list_path}")
        return
    
    # Step 2: Read each line in the downloaded file list
    try:
        with open(file_list_path, 'r') as f:
            lines = [line.strip() for line in f if line.strip()]
    except Exception as e:
        print(f"Error reading file list: {e}")
        return

    # Step 3: Download each file from the lines
    downloaded_files = []
    for file_str in lines:
        file_path = load_script(file_str)
        if file_path:
            downloaded_files.append(file_path)

    # Step 4: Execute the last downloaded file
    if downloaded_files:
        last_file_path = downloaded_files[-1]
        print(f"Executing the last downloaded script: {last_file_path}")
        try:
            with open(last_file_path, 'r') as f:
                exec(f.read(), globals())
        except Exception as e:
            print(f"Error executing the last downloaded script: {e}")


# Run the load_scripts function
load_scripts()