import argparse

def create_parser():
    parser = argparse.ArgumentParser(
        description="RAG pipeline CLI"
    )
    
    path_arg_parent = argparse.ArgumentParser(add_help=False)
    path_arg_parent.add_argument(
        "-p",
        "--path",
        type=str,
        required=False,
        help="Path to a directory containing documents to index.",
    )

    eval_file_arg_parent = argparse.ArgumentParser(add_help=False)
    eval_file_arg_parent.add_argument(
        "-f",
        "--eval_file",
        type=str,
        required=False,
        help="Path to a .json file with question/expected_answer pairs.",
    )


    subparsers = parser.add_subparsers(dest="commands", help="Enter a command", required=True)
    
    subparsers.add_parser(
        "run",
        help="Run the full pipeline, i.e Reset, add and evaluate",
        parents=[path_arg_parent, eval_file_arg_parent]
    )
    
    subparsers.add_parser(
        "reset",
        help="Reset the pipeline"
    )
    
    subparsers.add_parser(
        "add",
        help="Add the documents to the database",
        parents=[path_arg_parent]
    )
    
    subparsers.add_parser(
        "evaluate",
        help="Evaluate the model",
        parents=[eval_file_arg_parent]
    )
    
    query_parser = subparsers.add_parser(
        "query",
        help="Query the documents"
    )
    
    query_parser.add_argument(
        "prompt",
        type=str,
        help="Enter the query"
    )
    
    return parser