import re
from datetime import date, datetime

from .types import Event

def parse_date(id: str, name: str, input: str, apple_omit_year: str | None = None) -> Event:
    if isinstance(input, date):
        return Event(id, name, input.day, input.month, input.year)
    
    match = re.match(r"^(-|NaN)-(\d{2})-?(\d{2})$", input) # no-year format: --MMDD or --MM-DD. Also NaN-MM-DD spotted
    if match:
        return Event(id, name, int(match.group(3)), int(match.group(2)))
    
    for fmt in ("%Y-%m-%d", "%Y%m%d"):
        try:
            dt = datetime.strptime(input, fmt).date()
            if apple_omit_year == f"{dt.year}":
                return Event(id, name, dt.day, dt.month)
            else:
                return Event(id, name, dt.day, dt.month, dt.year)
        except ValueError:
            continue
    
    return None # cannot parse