"""Misc utility classes and functions.

======================================

"""
import os

from salessheets.constants import pdf


class DotDict(dict):
    """A wrapper around dict to access its items using dot notation."""

    def __getattr__(self, item):
        """Get item from dictionary by it's key, using dot-notation.

        Args:
            item (str): key

        Returns:
            value, or None if there is no item with such key
        """
        return self.get(item)

    def __setattr__(self, key, value):
        """Set value in dictionary, using dot-notation.

        Args:
            key (str): item key
            value: item value
        """
        self[key] = value


class EmptyDateException(Exception):
    """Raise when date field is empty."""

    def __init__(self, arg):
        """Initiate exception with message."""
        self.message = arg


def datetime_to_str(date, date_format=pdf.REDESSENT_DATETIME_FORMAT):
    """Convert datetime object to string.

    Args:
        date (datetime object)
        date_format (str): string for date formatting.
    Returns:
        str: date string
    """
    try:
        date_string = date.strftime(date_format)
        return date_string
    except AttributeError:
        raise EmptyDateException('Date should be the datetime object!')


def remove_file(path):
    """Remove a file, and silently return if it doesn't exist.

    Args:
        path (str): path to file
    """
    try:
        os.remove(path)
    except FileNotFoundError:
        pass


def split_text_in_paragraphs(text_str):
    r"""Split string into paragraphs by \r\n.

    Args:
        text_str (str): text to split

    Returns:
        list: list of paragraphs
    """
    return text_str.splitlines() if text_str else []


def cleanup_dict(dictionary):
    """Cleanup dictionary.

    Change None from dict elements to empty string, substitute values
    containing only spaces by empty string.
    Args:
        dictionary (dict): dictionary that should be cleaned from None.

    Returns:
        dict: cleaned dictionary.
    """
    for key, value in dictionary.items():
        # strings
        if isinstance(dictionary[key], str):
            dictionary[key] = dictionary[key].strip()
        # None
        elif dictionary[key] is None:
            dictionary[key] = ''
    return dictionary