"""Provides tools for reading from and writing to java properties files.
"""

from typing import Dict, Union, IO
from jproperties import Properties
import os
from os import path

# The default extension for property files in autopsy repo
DEFAULT_PROPS_EXTENSION = 'properties-MERGED'


def get_lang_bundle_name(language: str) -> str:
    """
    Returns the bundle name for the specific language identifier provided.
    Args:
        language: The language identifier (i.e. 'ja' for Japanese)

    Returns:
        The bundle name
    """
    return 'Bundle_{lang}.properties'.format(lang=language)


def get_entry_dict(file_contents: Union[str, IO]) -> Dict[str, str]:
    """Retrieves a dictionary mapping the properties represented in the string.

    Args:
        file_contents: The string of the properties file or the file handle.

    Returns:
        Dict[str,str]: The mapping of keys to values in that properties file.
    """

    props = Properties()
    try:
        props.load(file_contents)
    except Exception as e:
        raise Exception("There was an error loading properties file {file}".format(file=file_contents), e)
    return props.properties


def get_entry_dict_from_path(props_path: str) -> Union[Dict[str, str], None]:
    """
    Retrieves a dictionary mapping the properties represented in the string or None if no properties file can be found
    at that path.
    Args:
        props_path: The path to the properties file.

    Returns: The entry dictionary for that properties file.

    """
    if os.path.isfile(props_path):
        with open(props_path, "rb") as f:
            return get_entry_dict(f)
    else:
        return None


def set_entry_dict(contents: Dict[str, str], file_path: str):
    """Sets the property file to the key-value pairs of the contents dictionary.

    Args:
        contents (Dict[str, str]): The dictionary whose contents will be the key value pairs of the properties file.
        file_path (str): The path to the properties file to create.
    """

    props = Properties()
    for key, val in contents.items():
        props[key] = val

    parent_dir, file = os.path.split(file_path)
    if not os.path.exists(parent_dir):
        os.makedirs(parent_dir)

    with open(file_path, "wb") as f:
        props.store(f)


def update_entry_dict(contents: Dict[str, str], file_path: str):
    """Updates the properties file at the given location with the key-value properties of contents.  
    Creates a new properties file at given path if none exists.

    Args:
        contents (Dict[str, str]): The dictionary whose contents will be the key value pairs of the properties file.
        file_path (str): The path to the properties file to create.
    """
    contents_to_edit = contents.copy()

    cur_dict = get_entry_dict_from_path(file_path)
    if cur_dict is None:
        cur_dict = {}
    for cur_key, cur_val in cur_dict.items():
        # only update contents if contents does not already have key
        if cur_key not in contents_to_edit:
            contents_to_edit[cur_key] = cur_val

    set_entry_dict(contents_to_edit, file_path)