from dataclasses import dataclass
from datetime import date, timedelta
from typing import List, Union


@dataclass
class DateRange:
    start: date
    end: date

    def __init__(self, start: date, end: date):
        self.start = start or end
        self.end = end or start


def merge_date_ranges(date_ranges: List[DateRange]):
    combined_ranges = []

    new_range_item_start = None
    new_range_item_end = None

    length = len(date_ranges)
    for i, range_item in enumerate(date_ranges):
        current_range_start = range_item.start
        current_range_end = range_item.end

        if new_range_item_start is None:
            new_range_item_start = current_range_start
            new_range_item_end = current_range_end
        elif new_range_item_end >= current_range_start:
            new_range_item_end = max(current_range_end, new_range_item_end)
        else:
            combined_ranges.append((new_range_item_start, new_range_item_end))
            new_range_item_start = current_range_start
            new_range_item_end = current_range_end

        if i + 1 == length:
            combined_ranges.append((new_range_item_start, new_range_item_end))

    return [DateRange(date_range[0], date_range[1]) for date_range in combined_ranges]


def dates_between(start_date: date, end_date: date):
    for n in range(int((end_date - start_date).days + 1)):
        yield start_date + timedelta(n)


def compare_dates(date_1: Union[str, date], date_2: Union[str, date]) -> bool:
    if type(date_1) == date:
        date_1 = date_1.isoformat()

    if type(date_2) == date:
        date_2 = date_2.isoformat()

    return date_1 == date_2