"""
General utility functions for DICOM operations.
"""
import os
import json
from datetime import datetime
from utils.logger import main_logger as logger

def create_directory_if_not_exists(directory_path):
    """
    Create directory if it doesn't exist.
    
    Args:
        directory_path (str): Path to directory
    """
    if not os.path.exists(directory_path):
        os.makedirs(directory_path, exist_ok=True)
        logger.info(f"Created directory: {directory_path}")

def save_json_data(data, filename, directory):
    """
    Save data as JSON to specified directory.
    
    Args:
        data (dict): Data to save
        filename (str): Filename without path
        directory (str): Directory to save to
        
    Returns:
        str: Full path to saved file
    """
    create_directory_if_not_exists(directory)
    file_path = os.path.join(directory, filename)
    
    with open(file_path, 'w') as f:
        json.dump(data, f, indent=2)
    
    logger.info(f"Saved JSON data to {file_path}")
    return file_path

def parse_dicom_date(date_str):
    """
    Parse DICOM date format (YYYYMMDD) to Python datetime.
    
    Args:
        date_str (str): DICOM formatted date string
        
    Returns:
        datetime: Python datetime object
    """
    if not date_str or len(date_str) != 8:
        return None
    
    try:
        return datetime.strptime(date_str, '%Y%m%d')
    except ValueError:
        logger.error(f"Invalid DICOM date format: {date_str}")
        return None

def parse_dicom_datetime(datetime_str):
    """
    Parse DICOM datetime format (YYYYMMDDHHMMSS) to Python datetime.
    
    Args:
        datetime_str (str): DICOM formatted datetime string
        
    Returns:
        datetime: Python datetime object
    """
    if not datetime_str:
        return None
    
    # Handle various DICOM datetime formats
    try:
        if len(datetime_str) == 14:  # YYYYMMDDHHMMSS
            return datetime.strptime(datetime_str, '%Y%m%d%H%M%S')
        elif len(datetime_str) == 12:  # YYYYMMDDHHMM
            return datetime.strptime(datetime_str, '%Y%m%d%H%M')
        elif len(datetime_str) == 8:  # YYYYMMDD
            return datetime.strptime(datetime_str, '%Y%m%d')
        else:
            logger.warning(f"Unexpected DICOM datetime format: {datetime_str}")
            return None
    except ValueError:
        logger.error(f"Invalid DICOM datetime format: {datetime_str}")
        return None